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Hybrid myocardial revascularization

  • Yugal Kishore MishraEmail author
  • Jatin Yadav
Review Article
  • 34 Downloads

Abstract

Background

In patients with advanced coronary artery disease (CAD), coronary artery bypass grafting (CABG) is associated with improved long-term outcomes while percutaneous coronary intervention (PCI) is associated with lower periprocedural complications. A new approach has emerged in the last decade that attempts to reap the benefits of bypass surgery and stenting while minimizing the shortcomings of each approach, hybrid myocardial revascularization (HMR).Three strategies for timing of the hybrid revascularization exists, each with their own inherent advantages and shortcomings: (1) CABG followed by PCI, (2) PCI followed by CABG, or (3) simultaneous CABG + PCI in a hybrid suite.

Studies

The results of the first randomized control trial comparing HMR (CABG first) and standard CABG, POL-MIDES (Prospective Randomized PilOt Study EvaLuating the Safety and Efficacy of Hybrid Revascularization in MultIvessel Coronary Artery DisEaSe), show HMR was feasible for 93.9% of patients whereas conversion to standard CABG was required for 6.1%. At 1 year, both groups had similar all-cause mortality (CABG 2.9% vs. HMR 2%) and major adverse clinical event (MACE)-free survival rates (CABG 92.2% vs. HMR 89.8%). Results of observational and comparative studies show that minimally invasive HMR procedures in patients with multivessel CAD carry minimal perioperative mortality risk and low morbidity and do not increase the risk of postoperative bleeding. The advantage they offer in comparison to classical surgical revascularization is indeed faster rehabilitation and patient’s return to normal life.

Conclusion

Hybrid myocardial revascularization has been developed as a promising technique for the treatment of high-risk patients with CAD. Hybrid revascularization using minimally invasive surgical techniques combined with PCI offers to a part of patients an advantage of optimal revascularization of the most important artery of the heart, together with adequate myocardial revascularization in a relatively delicate way. Indeed, to patients with high operative risk of standard surgery, it offers an alternative which should be considered carefully.

Keywords

Coronary artery disease Hybrid myocardial revascularization LIMA-to-LAD grafting 

Introduction

Two main approaches to myocardial revascularization currently exist, coronary artery bypass grafting (CABG) surgery and percutaneous coronary intervention (PCI). In patients with advanced coronary artery disease (CAD), CABG is associated with improved long-term outcomes while PCI is associated with lower periprocedural complications. A new approach has emerged in the last decade that attempts to reap the benefits of bypass surgery and stenting while minimizing the shortcomings of each approach. This new approach, hybrid myocardial revascularization (HMR), has shown encouraging early results. Minimally invasive techniques for bypass surgery have played a large part in bringing this approach into contemporary practice.

According to the guidelines of the joint American societies on PCI and CABG [1], HMR is defined as planned procedures involving left internal mammary artery (LIMA)-to-left anterior descending (LAD) grafting and PCI of at least one non-LAD coronary artery. The 2011 American College of Cardiology Foundation (ACC)/American Heart Association (AHA) guidelines for CABG state that the “primary purpose of performing HMR is to decrease the morbidity rate of traditional CABG in high-risk patients” [2]. Even in the more recent European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines on myocardial revascularization [3], HMR has a class IIb recommendation for specific patient subsets but only at experienced centers.

The first reported HMR was performed in 1996 [4]. Although HMR was performed very infrequently for many years, more recently, an increasing number of these procedures are performed by cardiac surgeons and interventional cardiologists who function on collaborative heart teams and who have mastered advanced techniques in minimally invasive surgery and PCI, allowing them to safely traverse the significant learning curve associated with HMR.

The rationale for hybrid myocardial revascularization

The rationality for hybrid revascularization procedures is based on three premises.
  1. a.

    The LIMA-to-LAD graft is probably the best revascularization method for this artery considering the long-term patency and the resulting influence on the prognosis of the patient [5, 6, 7].

     
  2. b.

    PCI with stent implantation on other arteries has comparable results with surgical revascularization with venous or other arterial grafts. It alone does not lead to impaired prognosis when compared with surgical treatment [8, 9].

     
  3. c.

    Minimally invasive surgical techniques allow for LIMA-to-LAD grafting with a limited operational trauma and with exclusion of extracorporeal circulation.

     

The survival benefit of a surgical LIMA-to-LAD graft

The LAD artery is the most important coronary artery as it supplies approximately 60% of the myocardium of the left ventricle [10]. Successful revascularization of this artery is therefore a logical requirement for improving long-term prognosis of patients [11, 12]. A unique conduit, the LIMA powerfully resists thrombosis and atherosclerosis [13]. Consequently, the LIMA-to-LAD graft is associated with long-term patency rates reaching 98% at 10 years [14, 15]. Furthermore, a LIMA graft protects the native coronary tree from the deleterious effects of disease progression [13]. In the Bypass Angioplasty Revascularization Investigation (BARI) trial, the superiority of CABG to PCI in patients with diabetes was found only in patients in whom LAD was revascularized with LIMA. Patients with venous LAD grafts had the same prognosis as patients treated with PCI [16]. Both the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) [9] and the Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease (FREEDOM) [17] trials concur with these results, and the presence of a proximal LAD lesion in patients with multivessel disease strongly indicates a surgical revascularization with LIMA.

Surgical revascularization outside the LAD territory—comparison with PCI

Unlike arterial conduits, veins were not designed to bear the load of systemic pressure; hence, saphenous vein grafts (SVG) are more prone to atherosclerotic degeneration and progressive narrowing with high early and long-term failure rates. After 1 year, the incidence of bypass closure is given in the range of 12–30% [18, 19]. In a large trial with more than 3000 patients, 26% of all venous grafts were occluded in 12 months and at least one bypass was occluded or non-functional in 42% of patients [20]. This trial represents data similar to real life. In the 5-year follow-up, further degradation of venous grafts occurs, and only 60% of the grafts remain patent. After 10 years, only about half of the grafts are patent [21]. The uses of other arterial grafts have contradictory results. In some trials, long-term patency of radial artery grafts was similar to the patency of venous grafts [22, 23]. Long-term patency of right internal mammary artery (RIMA) graft lies somewhere in the middle of venous grafts and LIMA [9]. However, revascularization using RIMA is not widely used for concerns with higher incidence of infective complications at the sternotomy site [24, 25].

Newer drug-eluting stent (DES) platforms with (e.g., everolimus-eluting stents [EES] or zotarolimus-eluting stents [ZES]) or without (bioresorbable polymer-based or polymer-free stents) durable polymers show favorable outcomes, with 1-year target lesion revascularization (TLR) rates as low as 3 to 3.25% [8] and midterm binary (≥ 50%) restenosis rates of 2.3% for EES (8 months) [26] and 3.1% for the amphilimus-eluting, polymer-free stent (6 months) [27]. Even in high-risk patients and complex lesions, ZES and EES maintain very low 1-year TLR rates of 4.4 and 4%, respectively [28]. Considering the above, revascularization of arteries other than LAD with drug-eluting stents is an acceptable alternative to venous or other types of arterial grafts, even with the anticipated clinically significant restenosis.

Moreover, significant angiographic SVG stenosis occurs at least twice as frequently as binary in-stent restenosis using the latest technology platforms. However, ischemia-driven revascularization rates are considerably higher in stented patients with treated multivessel CAD [29]. Furthermore, even though SVG occlusion occurs at a higher rate compared with stent thrombosis [14], the clinical consequences of the latter are more dramatic, as it is more frequently associated with major adverse clinical events (MACE) [30].

Advantages of HMR procedures

HMR provides several advantages over conventional CABG, especially in high-risk patients with left main disease, left ventricular systolic dysfunction, advanced age, prior CABG, and comorbidities, who are poor surgical candidates for on-pump CABG and who are not likely to tolerate cardiopulmonary bypass (CPB) well [31]. Another likely advantage of HMR over conventional CABG is the avoidance of cerebrovascular accidents associated with CPB and aortic atheromas liberated during cross-clamping or cannulation [32].

Indications for hybrid myocardial revascularization

HMR might be considered in patients with multiple CAD including the proximal LAD who are indicated for surgery, and standard surgery is for some reason considered risky [33, 34]. Cardiac risk factors comprise poor left ventricular function, recent myocardial infarction, and difficulty to perform surgery on coronary arteries other than LAD, for example proximal stenosis eligible for PCI and quality of distal arteries unsuitable for a reliable bypass anastomosis or absence of suitable conduits, respectively (i.e., unavailability of venous grafts). This concerns equally the patients who had emergent PCI performed on coronary arteries other than LAD due to acute coronary syndrome and have LAD stenosis that is not optimally suitable for further intervention, for example chronic occlusion or complex lesions. Further risk factors include vast calcification of the aorta or mitral annulus that increases the risk of perioperative cerebral stroke while being manipulated. The preference of a patient demanding the less invasive procedure even after being informed about the bypass surgery as a standard procedure in the particular case, should be also taken into consideration [35]. Complex distal left main lesions are also ideal for HMR if the circumflex artery territory is amenable for PCI.

Clinical conditions

1. Hemodynamic instability

2. Malignant ventricular arrhythmias

3. Decompensated congestive heart failure or severely depressed ejection fraction

4. History of chronic lung disease (FEV1 < 50%) predicted or home oxygen dependence precluding intubation

5. Coagulopathy (increasing risk of bleeding)

6. History of pericarditis

7. Prior left thoracotomy

Conditions that exclude LIMA-to-LAD grafting

1. Unusable or previously used LIMA

2. Previous thoracic surgery involving the left pleural space

3. Poor quality or diffusely diseased LAD

4. Chest wall irradiation

5. Left subclavian artery stenosis

Conditions that exclude PCI

1. Intolerance to dual antiplatelet drugs (allergy or intolerance)

2. Severe peripheral vascular disease precluding femoral, radial or brachial access

3. Lesion characteristics indicative of a high predicted risk of restenosis

4. Risk of contrast induced nephropathy

Limitations for hybrid myocardial revascularization

1. Longer operating time

2. Technically demanding for the surgeon

3. Lower anastomosis patency depending on the learning curve

4. Need for intraoperative imaging requiring hybrid suite

5. Collaboration between surgeons and cardiologists

Contraindications for hybrid myocardial revascularization

Patients with a predicted high incidence of morbidity and mortality with conventional CABG

1. Advanced age

2. Marked frailty

3. Multiple comorbidities

4. Important cerebrovascular impairment with the history of cerebral stroke or paraplegia

5. Serious carotid arteries disease

6. Pulmonary illness if it enables single-lung ventilation

Conditions increasing the complication rates for sternotomy

1. Previous sternotomy (reoperation)

2. History of sternal infection

3. Previous mediastinitis

4. Tumors affecting the sternum (e.g. myeloma) Previous thorax radiation treatment

5. Corticosteroid therapy

6. Severe obesity with diabetes

7. Important mobility impairment restricting the subsequent rehabilitation (crutches, wheelchair)

Specific cardiac risk factors

1. Impaired left ventricular function

2. Recent myocardial infarction

3. Difficulty to perform surgery on coronary arteries other than LAD (e.g. unfavorable non-LAD targets or distal lesions in circumflex or right coronary artery)

Others

1. Absence of suitable venous or arterial conduits

2. Patients unwilling to undergo median sternotomy

3. LAD lesion with suitable caliber for minimally invasive or endoscopic CABG

4. Vast calcification of the aorta or mitral annulus

Elective hybrid revascularization is contraindicated in hemodynamically unstable patients including acute myocardial infarction and cardiogenic shock, in patients with severe decompensated ischemic cardiomyopathy and in patients with serious lung disease that preclude ventilation of one lung or with severe right ventricular dysfunction. Conditions impeding the reliable performance of LIMA-to-LAD anastomosis are history of pericarditis, previous left thoracotomy or left pleural area surgery, extensive pleural adhesions in left pleural space, use of, or damage to LAD in previous cardiac surgery, unsatisfactory quality of LAD, and important stenosis or occlusion of left subclavian artery when not treated beforehand. It is obvious that it is not suitable to consider combined therapy in case that PCI on coronary arteries other than LAD is not technically feasible or highly risky. Renal dysfunction with the risk of contrast-induced nephropathy and intolerance of prolonged clopidogrel treatment may also play an important role in the decision-making process.

Hybrid myocardial revascularization strategies

Three strategies for timing of the hybrid revascularization exist, each with their own inherent advantages and shortcomings: (1) CABG followed by PCI, (2) PCI followed by CABG, or (3) simultaneous CABG + PCI in a hybrid suite.

Staged hybrid myocardial revascularization

Although ACC/AHA guidelines recommend performing CABG first, ultimate decision should be taken by the “Heart Team.”
  1. A.

    CABG followed by PCI

     
Assessment of LIMA-to-LAD graft anastomosis can be performed during coronary angiography just prior to PCI [36]. This strategy also facilitates full antiplatelet inhibition following CABG with no perioperative bleeding risk and provides a protected anterior wall, lowering procedural risks during PCI of non-LAD vessels. In addition, the incidence of emergent CABG following a PCI complication or failure is exceedingly rare with the advent of stenting (< 1%) [37]. This has given a degree of security to the performance of the PCI after the CABG. The disadvantages of a CABG-first approach include the risk of ischemia of non-LAD territories during the LIMA-to-LAD grafting (although highly unlikely in stable patients) and the potential for a high-risk surgical reintervention following unsuccessful PCI.
  1. B.

    PCI followed by CABG

     

Advantages of a PCI prior to surgery strategy include lower risks of ischemia during surgery and the possibility of performing grafting of non-LAD arteries in the case of suboptimal PCI results. It has the additional benefit of saving the patient the excess risk of repeat femoral access for the PCI segment of the HMR, in cases where the approach is decided upon at the time of diagnostic catheterization. A PCI-first approach also allows angiographic evaluation of the LIMA’s size.

Nonetheless, the risk of PCI-related complications like intimal disruption, thrombus formation or embolization, and dissection may necessitate maximal anticoagulant pharmacotherapy with aspirin and clopidogrel, which increases the risk of bleeding complications, and may ultimately delay CABG. Its disadvantages also include a higher risk of stent thrombosis with discontinuation of dual antiplatelet therapy [DAPT], administration of plasma/platelet products in case of surgical bleeding, and the inflammatory response to surgery, and risk of adverse events in the LAD territory in the between-stages interval. A PCI-first approach does not allow angiographic validation of the “prognostic” LIMA-to-LAD graft and is not ideal in high-risk patients requiring extensive non-LAD percutaneous revascularization. However, a PCI-first approach is reasonable in patients presenting with acute coronary syndrome (ACS) who undergo non-LAD culprit lesion PCI followed by CABG of the LAD. If the lesions treated with PCI were the culprit ones, CABG can be delayed, allowing safe discontinuation of DAPT. This strategy may also be used in lesions with a risk of PCI failure, in other words chronic total occlusions, and in partially revascularized patients after PCI for an ACS.

Simultaneous CABG and PCI

A simultaneous approach is only feasible in hybrid suites featuring state-of-the-art surgical and interventional equipment. Often, CABG is performed first, allowing the interventional cardiologist to study the LIMA-to-LAD graft before stent implantation. Thus, PCI to high-risk, non-LAD lesions is performed with a protected LAD territory. In case of unsuccessful stent implantation, surgical bailout graft implantation remains an option. Additionally, the simultaneous HMR approach can be cost-effective by reducing hospital length of stay [38, 39] and the risk of lesion destabilization, and recurrent hospital admissions between staged procedures. An additional advantage improved patient satisfaction [38], as it condenses revascularization into one patient encounter [2]. As for the limitations of this approach, one challenge is balancing the need for appropriate antiplatelet therapy, to avoid stent thrombosis, with surgical bleeding risk. Performing the LIMA-to-LAD anastomosis under DAPT can be difficult, particularly when a minimally invasive approach and robotic-assisted LIMA take-down are used. Furthermore, the response of DES to protamine administration at the end of CABG has not been fully investigated [40]. When DAPT is not administered to reduce surgical bleeding risk, PCI becomes risky and is not recommended. Another challenging scenario for simultaneous HMR is the patient with chronic kidney disease (CKD), who is exposed in a short period of time to the dual nephrotoxic insult of surgery and contrast media.

Advantages and Disadvantages of Simultaneous and Staged HMR Procedures [41]

One stage (simultaneous)

Two-stage HMR

CABG followed by PCI within minutes

CABG first, then PCI

PCI first, then CABG

Advantages

Advantages

Advantages

• LIMA-to-LAD graft can be studied by the interventional cardiologist before PCI stent implantation

• Allows angiographic validation of the LIMA-to-LAD graft

• Allows angiographic evaluation of the size of LIMA

• PCI to high-risk non-LAD lesions can be performed with a protected LAD area

• Full antiplatelet inhibition following CABG with no perioperative bleeding risk

• Lower risk of ischemia during CABG in a partially revascularized heart

• In cases of unsuccessful stent implantation, conventional CABG remains an option

• Protected anterior wall, lowering procedural risks during PCI of non-LAD vessels

• Useful in the setting of acute myocardial infarction when culprit is a non-LAD lesion

• Cost-effective, as it reduces hospital length of stay (single-step complete revascularization)

• On some occasions, after minimally invasive LIMA to LAD, patients become asymptomatic in the immediate postoperative period

• In cases of unsuccessful stent implantation, suboptimal CABG can be performed

• Patient satisfaction: condenses revascularization therapy in one patient encounter

  

Disadvantages

Disadvantages

Disadvantages

• Only feasible in hybrid suites, featuring state-of-the-art surgical and interventional equipment

• Risk of ischemia of non-LAD territories during the LIMA-to-LAD grafting (although this is very unlikely in stable patients)

• No angiographic control of LIMA-to-LAD graft

• Inflammatory response to surgery offers a risk for stent thrombosis

• Risk of a high-risk surgical reintervention in case of an unsuccessful PCI

• Higher risk of stent thrombosis during surgery (due to inflammatory response to surgery/discontinuation of DAPT/platelet transfusion)

• DAPT increases the risk of bleeding

 

• Increased perioperative bleeding risk due to DAPT during surgery

• CKD patients are exposed to the dual nephrotoxic insult of surgery and contrast media utilization

 

• Risk of adverse events in the LAD territory during the between stages interval

The individual components of HMR

The LIMA-to-LAD anastomosis

A number of minimally invasive techniques have been developed to anastomose the LIMA to the LAD, which aim to avoid cardiopulmonary bypass and the sternotomy incision.
  1. 1.

    Minimally invasive direct coronary artery bypass grafting (MIDCAB)—it is performed on the beating heart through a small, left-sided thoracotomy in the fourth or fifth interspace. The retraction of ribs allows manual preparation of LIMA and performance of anastomosis under direct visual control. Data from many trials show that MIDCAB has a fully comparable long-term patency of LIMA graft with the classical approach with a sternotomy, with low perioperative morbidity and mortality and very good mid- and long-term results, comparable with off-pump coronary artery bypass (OPCAB) access [42, 43].

     
  2. 2.

    In an effort to avoid the significant chest wall manipulation associated with MIDCAB and to improve postoperative pain control, thoracoscopic and robotic techniques have been developed.

     
  1. a)

    Endoscopic atraumatic coronary artery bypass (Endo-ACAB)—this technique does not require a wide retraction of ribs, which is a must for the LIMA preparation. Access is obtained via three endoscopic ports placed in approximately the third, fifth, and seventh intercostal spaces. This technique allows thoracoscopic LIMA identification and harvesting along its entire length, mimicking what is typically accomplished via median sternotomy. Both pericardiotomy and target vessel localization can be performed endoscopically, thus limiting the size of the thoracotomy and the degree of requisite retraction. A small 4–5-cm anterior minithoracotomy is performed over the LAD, and a non-rib spreading soft tissue retractor is used to provide adequate visualization for placement of the stabilizer and completion of the hand-sewn anastomosis [44]. Perioperative and long-term results in the largest population of patients operated this way (607) were excellent, with the graft patency at 5 years being 98.5 and 95% of the patients without cardiovascular event at 5 years [45]. This method requires insufflation of left hemithorax with possible negative effects on hemodynamic state and oxygenation of the patient. Its usage is therefore limited in patients with pulmonary obstruction or hypertension and in patients with severe left ventricular dysfunction or active ischemia. It also cannot be used in patients with prior thoracic operations and in patients with pleural adhesions [46]. The necessity of managing advanced endoscopic techniques and a related long learning curve is probably the reason that has prevented the widespread use of this technique.

     
  2. b)

    Robotically enhanced minimally invasive direct coronary bypass (RECAB)—the development of robotics in recent years has allowed endoscopic collection of LIMA with the aid of robotic systems. The end-anastomosis on LAD can be performed manually using a limited thoracotomy without rib retraction. Trials published to date show a high primary success rate with the patency of the graft being 95–100%. There is low perioperative morbidity and a high rate of patient satisfaction [35, 47, 48, 49].

     
  3. c)

    Robot-assisted totally endoscopic coronary artery bypass (robotic TECAB)—some surgeons have successfully taken minimally invasive coronary revascularization a step further in performing robotic TECAB. In its early stages, this procedure was performed on the arrested heart, with intra-aortic balloon occlusion. Although the minithoracotomy is avoided, this approach carries with it the deleterious inflammatory response of CPB, theoretically negating any advantage over the robotic MIDCAB approach. The beating-heart TECAB technique, that was later developed successfully, avoids both the use of CPB and the necessity for a minithoracotomy. This technique although challenging produces a reported clinical freedom from graft failure as high as 98.6% at 13 months in experienced hands [50].

     
  1. 3.

    JOPCAB procedure—LIMA harvest and off-pump CABG (OPCAB) can be performed through an inferior left J-hemisternotomy under direct vision (a JOPCAB procedure).

     

Which type of stent to implant?

Without question, modern PCI should be performed with second- or third-generation DES. Irrespective of DES choice, it is essential that DAPT be continued for at least 6 months. Fully biodegradable DES are an interesting new development [51], but long-term follow-up data, especially in complex lesions, are needed before we consider them a replacement for current metallic DES.

Outcomes of hybrid myocardial revascularization

Summary of hybrid revascularization trial outcomes

Study (year)

Patients/controls (n)

HMR procedure

Surgical procedure

Timing

Follow-up

Authors’ conclusions

Shen et al. (2013) [52]

141/141

MIDCAB

CABG or PCI

Simultaneous

3 years

Similar MACCE in HMR versus CABG, but increased versus PCI. HMR higher MACCE than CABG in high SYNTAX score and euroSCORE patients

Leacche et al. (2013) [53]

80/301

OPCAB or CABG

OPCAB or CABG

Simultaneous

1 month

HMR a safe alternative to CABG increased repeat revascularization in HMR > 33 SYNTAX score

Bachinsky et al.(2012) [39]

25/27

Robotic MIDCAB

OPCAB

Simultaneous

1 month

HMR feasible and safe

Hu et al.(2011) [54]

104/104

MIDCAB

OPCAB

Simultaneous

1.5 years

HMR better 18-month clinical outcome (MACCE)

Halkos et al. (2011) [55]

147/588

MIDCAB

OPCAB

Staged

3.2 years

Similar rate of death and MACCE, revascularization increased in HMR

Halkos et al. (2011) [56]

27/81

MIDCAB

OPCAB

Staged

3.2 years

HMR is a safe and feasible in left main disease

Vassiliades et al.(2009) [44]

91/4175

MIDCAB

Endo-ACAB

Staged

3 years

HMR non inferior in 30-day MACCE and 3-year survival

Kon et al.(2006) [57]

15/30

MIDCAB

OPCAB

Simultaneous

1 year

Similar clinical results high patient satisfaction with HMR

Reicher et al. (2008) [58]

13/26

MIDCAB

OPCAB

Simultaneous

6 months

Similar safety and efficacy shorter hospital stay after HMR

de Cannière et al.(2001) [59]

20/20

MIDCAB

CABG

Mixed

2 years

Similar clinical results less perioperative morbidity

Kiaii (2008) [35]

58

RECAB

 

Simultaneous

1.8 year

HMR feasible and safe

Stahl et al. (2002) [60]

54

RECAB

 

Mixed

11 month

HMR feasible and safe

Davidavicius (2005) [61]

20

RECAB

 

Mixed

19 month

HMR feasible and safe

MACCE, major adverse cardiac and cerebrovascular event; OPCAB, off-pump coronary artery bypass grafting

In spite of theoretical attractiveness of hybrid revascularization concept, the quantity of workplaces dedicated to this issue remains quite small and published data are scarce. The majority of studies that followed were single-center observational studies comprising limited number of patients. In addition, they are considerably heterogeneous with respect to selection criteria, hybrid procedure strategy, surgical technique, mode of intervention, outcome assessment, and follow-up length. From presented data, it is possible to say that HMR is safe. Perioperative mortality ranged between 0 to 2%, and average mortality of all studies is 0 to 3%. Medium-term graft patency to LAD is high—92 to 100% and fully comparable to the data from standard methods [42, 43]. Medium-term survival without adverse events is 90% on average. These results could be compared, for instance, to the surgical arm of SYNTAX study, where patients with multiple CAD were revascularized mostly with arterial grafts and where the overall mortality after 12 months was 3.5%, necessity for subsequent revascularization 5.9% and adverse event-free survival 87.6%.

The results of the first randomized control trial (RCT) comparing HMR (CABG first) and standard CABG, POL-MIDES (Prospective Randomized PilOt Study EvaLuating the Safety and Efficacy of Hybrid Revascularization in MultIvessel Coronary Artery DisEaSe), were only recently published [62]. A total of 200 consecutive patients with angiographically confirmed multivessel CAD involving the proximal LAD and a significant (> 70%) lesion in at least one major non-LAD epicardial vessel amenable to both PCI and CABG were randomized in a 1:1 fashion to HMR (n = 98) (using MIDCAB and cobalt chromium EES) or conventional CABG (n = 102). Both groups had similar baseline demographic characteristics, risk factor profiles, and SYNTAX scores. HMR was feasible for 93.9% of patients whereas conversion to standard CABG was required for 6.1%. At 1 year, both groups had similar all-cause mortality (CABG 2.9% vs. HMR 2%) and MACE-free survival rates (CABG 92.2% vs. HMR 89.8%).

A recent RCT by Ganyukov et al., Hybrid REvascularization Versus Standards (HREVS), is a prospective, single-center, randomized, open-label, parallel group, safety and efficacy study conducted from 2013 to 2017. In this study, 155 multivessel coronary artery disease (MCAD) patients were externally randomized on a 1:1:1 ratio into three groups i.e., CABG (50), PCI (53), and HMR (52). At 12 months, residual myocardial ischemia and MACCE were similar across the three study arms (CABG, HMR, PCI). HREVS at 12 months provides no evidence for HMR benefit(s) in patients in whom PCI, CABG, and hybrid coronary revascularization (HCR) are equally feasible [63].

Another multicenter observational study, Hybrid Coronary Revascularization for the Treatment of Multivessel Coronary Artery Disease, was conducted by Puskas et al. from 2012 to 2015. Over 18 months, 200 HCR and 98 multivessel PCI patients were enrolled at 11 sites. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE) (i.e., death, stroke, myocardial infarction, repeat revascularization) within 12 months postintervention. Mean age was 64.2 ± 11.5 years; 25.5% of patients were female, 38.6% were diabetic, and 4.7% had previous stroke. Thirty-eight percent had three-vessel coronary artery disease, and the mean SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score was 19.7 ± 9.6. Adjusted for baseline risk, MACCE rates were similar between groups within 12 months postintervention (hazard ratio [HR] 1.063; p = 0.80) and during a median 17.6 months of follow-up (HR 0.868; p = 0.53). These observational data from this first multicenter study of HCR suggest that there is no significant difference in MACCE rates over 12 months between patients treated with multivessel PCI or HCR, an emerging modality [64].

A meta-analysis was done by Zhu et al. in 2016 on hybrid coronary revascularization versus coronary artery bypass grafting for multivessel coronary artery disease (MCAD). The result showed HCR was non-inferior to CABG in terms of MACCE during hospitalization, and no significant difference was found between HCR and CABG groups in in-hospital and 1-year follow-up outcomes of death, MI, stroke, and the prevalence of AF and renal failure, whereas HCR was associated with a lower requirement of RBC transfusion and shorter length of stay in ICU and hospital than CABG. They concluded that HCR is feasible, safe, and effective for the treatment of multivessel coronary artery disease, with similar in-hospital and 1-year follow-up outcome, significantly lower requirement of RBC transfusion, and faster recovery compared with CABG [65].

A systematic review was done by Panoulas et al. in 2015 which concluded that HCR is feasible and safe for a particular target group (just over 60 years of age; mainly stable, CAD favorable anatomy; intermediate risk and SYNTAX scores; and preserved or mildly impaired left ventricular ejection fraction) with acceptable midterm outcomes that are non-inferior to conventional CABG. However, data for higher risk groups, who would theoretically benefit the most from HCR, are weak or lacking; hence, no inferences or generalizations can be made regarding the role of HCR in these patients [41].

Kon et al. compared a simultaneous approach HMR procedure including MIDCAB in 15 patients with 30 OPCAB controls [57]. The results were much in favor of the HMR procedure. Thus, HMR patients had better preoperative hemodynamics, needed fewer blood cell transfusions, had shorter intubation times and less postoperative increase of serum creatinine values, and reduced postoperative costs. Maximum pain scores were higher after MIDCAB, but the duration of time needed for pain to completely resolve was shorter for HMR. Overall satisfaction scores were significantly higher after the hybrid procedure. At 1 year, there was no mortality in either group. Major cardiac adverse events were noted in 7 of HMR and in 23% of OPCAB patients (p = 0.05). Patients returned to work or normal activities more quickly after HMR. Long-term graft patency was assessed using computed tomography angiography and demonstrated one stent failure in the hybrid group, compared with seven SVG failures in the OPCAB group (p = 0.062). In a meta-analysis by Harskamp et al. [66] comprising 1190 patients (1 case control and 5 propensity-matched studies), no significant differences were found for the composite of death, myocardial infarction, stroke, or repeat revascularization at 1 year (hazard ratio 0.49; 95% confidence interval 0.2 to 1.24; p = 0.13).

In a study from 2011, Hu et al. performed simultaneous HMR in 104 patients and compared 18-month clinical results with a 1:1 matched OPCAB group [54]. HMR procedure implied a JOPCAB procedure in patients pretreated with low-dose aspirin. Unfractionated heparin was given at the beginning of the operation and was reversed after the graft procedure. Clopidogrel was administered via a nasogastric tube before stenting and the patient was re-heparinized. The total HMR procedure required longer operation time compared with OPCAB, but the need for blood transfusion was reduced. After 18 months, MACCE-free survival in HMR-treated patients compared favorably with OPCAB (99.0 vs. 90.4%; p = 0.03).

The largest study of hybrid revascularization with robotic-assisted LIMA harvest (RECAB) was published by Kiaii et al. [35]. Percutaneous intervention was performed in hybrid theater immediately after bypass anastomosis in 58 patients out of 60 indicated (97%); conversion to sternotomy with full surgical revascularization was performed in two patients due to arrhythmias during bypass stitching. Most of the 65 stents used were drug-eluting ones (82%). Angiography immediately after surgery proved LIMA patency in 93% of grafts. LIMA patency rate was 91% at coronary angiography in total of 54 patients. There was restenosis in nine stents (15%, seven cases) and stent occlusion in two patients. Reintervention was performed in two patients only (3.4%). Similar outcomes were achieved by RECAB in trial on 54 patients by Stahl et al., in which 35% of patients underwent PCI before and the rest after the surgery. Perioperative mortality was insignificant; coronary re-angiography was performed in 18.5% patients during follow-up (average 11 months). The mammary graft was patent in all cases; two patients had in-stent restenosis and one patient had stent occlusion (5.2% out of total number of implanted stents). Reintervention was performed in one patient. Overall event-free survival was 87 and 97% of patients had no angina pectoris [60].

Davidavicius et al. published an interesting concept of rationalization for hybrid revascularizations [61]. In 20 patients, who were potentially eligible for hybrid revascularization (RECAB), functional evaluation of stenosis on arteries excluding LAD was performed using the fractional flow reserve (FFR). In 14 patients, it was performed before robotic-assisted procedure, in six of them thereafter. PCI was performed only in case of hemodynamically significant stenosis (FFR value lower than 0.80)—in 14 patients, all of whom had a standard stent implanted (95%). The intervention was postponed in six patients who did not have a hemodynamically significant stenosis. The robotic TECAB to LAD was complication-free; all arterial grafts were patent at postoperative angiography. At medium-term check-up after 19 months on average, none of the patients had cardiovascular adverse event and their stress test was negative. Only one patient underwent coronary re-angiography due to chest pain with angiographically and functionally non-significant in-stent restenosis (FFR higher than 0.80). FFR measurement enables restriction of PCI use only to lesions causing ischemia and thus lowering the risk of the procedure itself as well as the risk of significant restenosis.

Results of these observational and comparative studies show that minimally invasive HMR procedures in patients with multivessel CAD carry minimal perioperative mortality risk and low morbidity and do not increase the risk of postoperative bleeding. The medium-term cardiovascular adverse events rate including the necessity of further revascularization is acceptable. The advantage they offer in comparison to classical surgical revascularization is indeed faster rehabilitation and patient’s return to normal life. Nevertheless, available studies do not allow any definite conclusions neither about the overall effectivity on hard clinical endpoints (mortality, myocardial infarction) when compared to standard surgery methods, nor about the long-term effects. The only way to assess the real clinical value of hybrid revascularization in comparison to classical surgery (or percutaneous interventional treatment) is to provide an adequately large randomized trial which would monitor the classical hard endpoints such as perioperative and postoperative mortality indicators and overall patient quality of life through short-term and long-term follow-up. These trials should include low-risk patients so that the hybrid procedures could be introduced into the common clinical practice. An equally based trial should be performed, comparing the hybrid revascularization to PCI to answer the question whether it is clinically beneficial to expand the hybrid procedure indications to patients with less severe LAD disease.

Conclusion

Hybrid myocardial revascularization has been developed as a promising technique for the treatment of high-risk patients with CAD. Hybrid revascularization using minimally invasive surgical techniques combined with PCI offer to a subset of patients an advantage of optimal revascularization of the most important artery of the heart, together with adequate myocardial revascularization in a relatively delicate way. Indeed, to patients with high operative risk of standard surgery, it offers an alternative which should be considered carefully. The results of published hybrid revascularization trials show low perioperative mortality, morbidity, and quick rehabilitation as well as very acceptable medium-term outcomes. Nevertheless, present studies are mostly retrospective and observational, carried out on quite small number of patients, and therefore do not allow a clear short or medium comparison of hybrid to standard techniques. Questions concerning the use of hybrid revascularization techniques in treatment of patients with multiple coronary artery lesions can be answered only by randomized and adequately large prospective clinical studies. Meanwhile, the decision for hybrid revascularization in a particular patient will be based more on experience and possibilities of specific site than on evidence-based medicine.

Notes

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies involving human or animals.

Informed consent

Not applicable as no human subjects involved.

References

  1. 1.
    Fihn SD, Gardin JM, Abrams J, et al. 2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS guideline for the diagnosis and management of patients with stable ischemic heart disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American College of Physicians, American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. J Am Coll Cardiol. 2012;60:44–164.CrossRefGoogle Scholar
  2. 2.
    Hillis LD, Smith PK, Anderson JL, et al. 2011 ACCF/AHA guideline for coronary artery bypass graft surgery: a report of the American College of Cardiology. Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2011;58:123–210.CrossRefGoogle Scholar
  3. 3.
    Windecker S, Kolh P, Alfonso F, et al. 2014 ESC/EACTS guidelines on myocardial revascularization: the Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). Eur Heart J. 2014;35:2541–619.CrossRefGoogle Scholar
  4. 4.
    Angelini GD, Wilde P, Salerno TA, Bosco G, Calafiore AM. Integrated left small thoracotomy and angioplasty for multivessel coronary artery revascularisation. Lancet. 1996;347:757–8.CrossRefGoogle Scholar
  5. 5.
    No authors listed. Coronary artery surgery study (CASS): a randomized trial of coronary artery bypass surgery. Survival data. Circulation. 1983;68:939–50.CrossRefGoogle Scholar
  6. 6.
    No authors listed. Comparison of coronary bypass surgery with angioplasty in patients with multivessel disease. N Engl J Med. 1996;335:217–25.CrossRefGoogle Scholar
  7. 7.
    No authors listed. The final 10-year follow-up results from the BARI randomized trial. J Am Coll Cardiol. 2007;49:1600–6.CrossRefGoogle Scholar
  8. 8.
    Navarese EP, Tandjung K, Claessen B, et al. Safety and efficacy outcomes of first and second generation durable polymer drug eluting stents and biodegradable polymer biolimus eluting stents in clinical practice: comprehensive network meta-analysis. BMJ. 2013;347:f6530.Google Scholar
  9. 9.
    Serruys PW, Morice MC, Kappetein AP, et al. Percutaneous coronary intervention versus coronary-artery bypass grafting for severe coronary artery disease. N Engl J Med. 2009;360:961–72.Google Scholar
  10. 10.
    Mahmarian JJ, Pratt CM, Boyce TM, Verani MS. The variable extent of jeopardized myocardium in patients with single vessel coronary artery disease: quantification by thalium-201 single proton emission computed tomography. J Am Coll Cardiol. 1991;17:355–62.CrossRefGoogle Scholar
  11. 11.
    Klein LW, Weintraub WS, Argawal JB, et al. Prognostic significance of severe narrowing of the proximal portion of the left anterior descending coronary artery. Am J Cardiol. 1986;58:42–6.CrossRefGoogle Scholar
  12. 12.
    Brener SJ, Lytle BW, Casserly IP, Schneider JP, Topol EJ, Lauer MS. Propensity analysis of long-term survival after surgical or percutaneous revascularisation in patients with multivessel coronary artery disease and high-risk features. Circulation. 2004;109:2290–5.CrossRefGoogle Scholar
  13. 13.
    Otsuka F, Yahagi K, Sakakura K, Virmani R. Why is the mammary artery so special and what protects it from atherosclerosis? Ann Cardiothorac Surg. 2013;2:519–26.Google Scholar
  14. 14.
    Tatoulis J, Buxton BF, Fuller JA. Patencies of 2127 arterial to coronary conduits over 15 years. Ann Thorac Surg. 2004;77:93–101.CrossRefGoogle Scholar
  15. 15.
    Hayward PA, Buxton BF. Contemporary coronary graft patency: 5-year observational data from a randomized trial of conduits. Ann Thorac Surg. 2007;84:795–9.CrossRefGoogle Scholar
  16. 16.
    Investigators BARI. The final 10-year follow-up results from the BARI randomized trial. J Am Coll Cardiol. 2007;49:1600–6.CrossRefGoogle Scholar
  17. 17.
    Farkouh ME, Domanski M, Sleeper LA, et al. Strategies for multivessel revascularization in patients with diabetes. N. Engl J Med. 2012;367:2375–84.Google Scholar
  18. 18.
    Puskas JD, Williams WH, Mahoney EM, et al. Off-pump vs conventional coronary artery bypass grafting: early and 1-year graft patency, cost, and quality-of-life outcomes: a randomized trial. JAMA. 2004;291:1841–9.Google Scholar
  19. 19.
    Barner HB. Operative treatment of coronary atherosclerosis. Ann Thorac Surg. 2008;85:1473–82.CrossRefGoogle Scholar
  20. 20.
    Alexander JH, Hafley G, Harrington RA, et al. Efficacy and safety of Edifoligide, an E2F transcription factor decoy for prevention of vein graft failure following coronary artery bypass graft surgery. PREVENT IV: a randomised controlled trial. JAMA. 2005;294:2446–54.CrossRefGoogle Scholar
  21. 21.
    Sabik JF 3rd, Lytle BW, Blackstone EH, Houghtaling PL, Cosgrove DM. Comparison of saphenous vein and internal thoracic artery graft patency by coronary system. Ann Thorac Surg. 2005;79:544–51.CrossRefGoogle Scholar
  22. 22.
    Khot UN, Friedman DT, Patterson G, Smedira NG, Li J, Ellis SG. Radial artery bypass grafts have an increased occurrence of angiographically severe stenosis and occlusion compared with left internal mammary arteries and saphenous vein grafts. Circulation. 2004;109:2086–91.CrossRefGoogle Scholar
  23. 23.
    Hayward PA, Gordon IR, Hare DL, et al. Comparable patencies of the radial artery and right internal thoracic artery or saphenous vein beyond 5 years: results from the radial artery patency and clinical outcomes trial. J Thorac Cardiovasc Surg. 2010;139:60–7.CrossRefGoogle Scholar
  24. 24.
    Kouchoukos NT, Wareing TH, Murphy SF, Pelate C, Marshall WG Jr. Risks of bilateral mammary artery bypass grafting. Ann Thorac Surg. 1990;49:210–9.CrossRefGoogle Scholar
  25. 25.
    Grossi EA, Esposito R, Harris LJ, et al. Sternal wound infections and use of internal mammary artery grafts. J Thorac Cardiovasc Surg. 1991;102:342–7.Google Scholar
  26. 26.
    Stone GW, Midei M, Newman W, et al. Comparison of an everolimus-eluting stent and a paclitaxel-eluting stent in patients with coronary artery disease: a randomized trial. JAMA. 2008;299:1903–13.CrossRefGoogle Scholar
  27. 27.
    Carrie D, Berland J, Verheye S, et al. A multicenter randomized trial comparing amphilimus- with paclitaxel-eluting stents in de novo native coronary artery lesions. J Am Coll Cardiol. 2012;59:1371–6.CrossRefGoogle Scholar
  28. 28.
    Stefanini GG, Serruys PW, Silber S, et al. The impact of patient and lesion complexity on clinical and angiographic outcomes after revascularization with zotarolimus- and everolimus-eluting stents: a substudy of the RESOLUTE All Comers Trial (a randomized comparison of a zotarolimus-eluting stent with an everolimus-eluting stent for percutaneous coronary intervention). J Am Coll Cardiol. 2011;57:2221–32.Google Scholar
  29. 29.
    Mohr FW, Morice MC, Kappetein AP, A, et al. Coronary artery bypass graft surgery versus percutaneous coronary intervention in patients with three-vessel disease and left main coronary disease: 5-year follow-up of the randomised, clinical SYNTAX trial. Lancet. 2013;381:629–38.Google Scholar
  30. 30.
    Farooq V, Serruys PW, Zhang Y, et al. Short-term and long-term clinical impact of stent thrombosis and graft occlusion in the SYNTAX Trial at 5 years: Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery Trial. J Am Coll Cardiol. 2013;62:2360–9.Google Scholar
  31. 31.
    Cohen HA, Zenati M, Smith AJ, et al. Feasibility of combined percutaneously transluminal angioplasty and minimally invasive direct coronary artery bypass in patients with multivessel coronary artery disease. Circulation. 1998;98:1048–50.CrossRefGoogle Scholar
  32. 32.
    Elefteriades JA. Mini-CABG: a step forward or backward: the “pro” point of view. J Cardiothorac Vasc Anesth. 1997;11:661–8.CrossRefGoogle Scholar
  33. 33.
    Us MH, Basaran M, Yilmaz M, et al. Hybrid coronary revascularisation in high risk patients. Tex Heart Inst J. 2006;33:458–62.Google Scholar
  34. 34.
    Hozhey DM, Jacobs S, Mochalski M, et al. Minimally invasive hybrid coronary artery revascularisation. Ann Thorac Surg. 2008;86:1856–60.CrossRefGoogle Scholar
  35. 35.
    Kiaii B, McClure S, Stewart P, et al. Simultaneous integrated coronary artery revascularisation with long-term angiographic follow-up. J Thorac Cardiovasc Surg. 2008;136:702–8.CrossRefGoogle Scholar
  36. 36.
    Friedrich GJ, Dapunt OE, Pachinger O. More on “hybrid revascularization.”. N Engl J Med. 1997;337:861–2.CrossRefGoogle Scholar
  37. 37.
    Serruys PW, Emanuelsson H, van der Giesen W, et al. Heparin-coated Palmaz-Schatz stents in human coronary arteries. Early outcome of the BENESTENT-II pilot study. Circulation. 1996;93:412–22.CrossRefGoogle Scholar
  38. 38.
    Kon ZN, Brown EN, Tran R, et al. Simultaneous hybrid coronary revascularization reduces postoperative morbidity compared with results from conventional off-pump coronary artery bypass. J Thorac Cardiovasc Surg. 2008;135:367–75.Google Scholar
  39. 39.
    Bachinsky WB, Abdelsalam M, Boga G, Kiljanek L, Mumtaz M, McCarty C. Comparative study of same sitting hybrid coronary artery revascularization versus off-pump coronary artery bypass in multivessel coronary artery disease. J Interv Cardiol. 2012;25:460–8.CrossRefGoogle Scholar
  40. 40.
    Byrne JG, Leacche M, Vaughan DE, Zhao DX. Hybrid cardiovascular procedures. JACC Cardiovasc Interv. 2008;1:459–68.Google Scholar
  41. 41.
    Panoulas VF, Colombo A, Margonato A, Maisano F. Hybrid coronary revascularization: promising, but yet to take off. J Am Coll Cardiol. 2015;65:85–97.CrossRefGoogle Scholar
  42. 42.
    Kettering K, Dapunt O, Baer FM. Minimally invasive direct coronary artery bypass grafting: a systematic review. J Cardiovasc Surg. 2004;45:255–64.Google Scholar
  43. 43.
    Holzhey DM, Jacobs MD, Mochalski M, et al. Seven-year follow-up after minimally invasive direct coronary artery bypass: experience with more than 1300 patients. Ann Thorac Surg. 2007;83:108–14.CrossRefGoogle Scholar
  44. 44.
    Vassiliades TA, Kilgo PD, Douglas JS, et al. Clinical outcomes after hybrid coronary revascularization versus off-pump coronary artery bypass: a prospective evaluation. Innovations (Phila). 2009;4:299–306.Google Scholar
  45. 45.
    Vassiliades TA, Reddy VS, Puskas JD, Guyton RA. Long-term results of the endoscopic atraumatic coronary artery bypass. Ann Thorac Surg. 2007;83:979–85.CrossRefGoogle Scholar
  46. 46.
    Byhahn C, Mierdl S, Meininger D, et al. Hemodynamics and gas exchange during carbon dioxide insufflation for totally endoscopic coronary artery bypass grafting. Ann Thorac Surg. 2007;71:1496–501.CrossRefGoogle Scholar
  47. 47.
    Subramanian VA, Patel NU, Patel NC, Loulmet DF. Robotic assisted multivessel minimally invasive direct coronary artery bypass with port-access stabilisation and cardiac positioning: paving the way for outpatient coronary surgery? Ann Thorac Surg. 2005;79:1590–6.CrossRefGoogle Scholar
  48. 48.
    De Rose JJ Jr, Balaram SK, Ro C, et al. Mid-term results and patient perceptions of robotically- assisted coronary artery bypass grafting. Interact Cardiovasc Thorac Surg. 2005;4:406–11.Google Scholar
  49. 49.
    De Rose JJ Jr, Balaram SK, Ro C, et al. Mid-term results and patient perceptions of robotically- assisted coronary artery bypass grafting. Interact Cardiovasc Thorac Surg. 2005;4:406–11.Google Scholar
  50. 50.
    Srivastava S, Gadasalli S, Agusala M, et al. Beating heart totally endoscopic coronary artery bypass. Ann Thorac Surg. 2010;89:1873–9.Google Scholar
  51. 51.
    Haude M, Erbel R, Erne P, et al. Safety and performance of the drug-eluting absorbable metal scaffold (DREAMS) in patients with de-novo coronary lesions: 12 month results of the prospective, multicentre, first-in-man BIOSOLVE-I trial. Lancet. 2013;381:836–44.Google Scholar
  52. 52.
    Shen L, Hu S, Wang H, et al. One-stop hybrid coronary revascularization versus coronary artery bypass graft and percutaneous coronary intervention for the treatment of multivessel coronary artery disease: three-year follow-up results from a single institution. J Am Coll Cardiol. 2013;61:2525–33.Google Scholar
  53. 53.
    Leacche M, Byrne JG, Solenkova NS, et al. Comparison of 30-day outcomes of coronary artery bypass grafting surgery versus hybrid coronary revascularization stratified by SYNTAX and euroSCORE. J Thorac Cardiovasc Surg. 2013;145:1004–12.Google Scholar
  54. 54.
    Hu S, Li Q, Gao P, et al. Simultaneous hybrid revascularization versus off-pump coronary artery bypass for multivessel coronary artery disease. Ann Thorac Surg. 2011;91:432–8.Google Scholar
  55. 55.
    Halkos ME, Vassiliades TA, Douglas JS, et al. Hybrid coronary revascularization versus off-pump coronary artery bypass grafting for the treatment of multivessel coronary artery disease. Ann Thorac Surg. 2011;92:1695–701.CrossRefGoogle Scholar
  56. 56.
    Halkos ME, Rab ST, Vassiliades TA, et al. Hybrid coronary revascularization versus off-pump coronary artery bypass for the treatment of left main coronary stenosis. Ann Thorac Surg. 2011;92:2155–60.Google Scholar
  57. 57.
    Kon ZN, Kwon MH, Collins MJ, et al. Off-pump coronary artery bypass leads to a regional hypercoagulable state not detectable using systemic markers. Innovations (Phila). 2006;1:232–8.Google Scholar
  58. 58.
    Reicher B, Poston RS, Mehra MR, Joshi A, Odonkor P, Kon Z, et al. Simultaneous 'hybrid' percutaneous coronary intervention and minimally invasive surgical bypass grafting: feasibility, safety, and clinical outcomes. Am Heart J. 2008;155:661–7.Google Scholar
  59. 59.
    de Cannière D, Jansens JL, Goldschmidt-Clermont P, Barvais L, Decroly P, Stoupel E. Combination of minimally invasive coronary bypass and percutaneous transluminal coronary angioplasty in the treatment of double-vessel coronary disease: two-year follow-up of a new hybrid procedure compared with 'on-pump' double bypass grafting. Am Heart J. 2001;142:563–70.CrossRefGoogle Scholar
  60. 60.
    Stahl KD, Boyd WD, Vassiliades TA, et al. Hybrid robotic coronary artery surgery and angioplasty in multi-vessel coronary artery disease. Ann Thorac Surg. 2002;74:S1358–62.Google Scholar
  61. 61.
    Davidavicius G, Van Praet F, Mansour S, et al. Hybrid revascularisation strategy: a pilot study on the association of robotically enhanced minimally invasive direct coronary artery bypass surgery and fractional-flow-reserve-guided percutaneous coronary intervention. Circulation. 2005;112:I317–22.Google Scholar
  62. 62.
    Gasior M, Zembala MO, Tajstra M, et al. Hybrid revascularization for multivessel coronary artery disease. JACC Cardiovasc Interv. 2014;7:1277–83.CrossRefGoogle Scholar
  63. 63.
    Ganyukov V, Kochergin N, Shilov A, et al. The comparative effectiveness of hybrid revascularization (MIDCAB Then PCI) with DES versus multivessel DES PCI or CABG (HREVS). Available from: https://clinicaltrials.gov/ct2/show/NCT01699048.
  64. 64.
    Puskas JD, Halkos ME, JJ DR, et al. Hybrid coronary revascularization for the treatment of multivessel coronary artery disease: a multicenter observational study. J Am Coll Cardiol. 2016;68:356–65.CrossRefGoogle Scholar
  65. 65.
    Zhu P, Zhou P, Sun Y, Guo Y, Mai M, Zheng S. Hybrid coronary revascularization versus coronary artery bypass grafting for multivessel coronary artery disease: systematic review and meta-analysis. J Cardiothorac Surg. 2015;10:63.CrossRefGoogle Scholar
  66. 66.
    Harskamp RE, Williams JB, Halkos ME, et al. Meta-analysis of minimally invasive coronary artery bypass versus drug-eluting stents for isolated left anterior descending coronary artery disease. J Thorac Cardiovasc Surg. 2014;148:1837–42.Google Scholar

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© Indian Association of Cardiovascular-Thoracic Surgeons 2018

Authors and Affiliations

  1. 1.Department of Cardiac SurgeryFortis Escorts Heart InstituteNew DelhiIndia

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