Coronary artery bypass graft surgery for the prevention of sudden cardiac death

Summary

Ventricular arrhythmias are responsible for most cases of sudden cardiac death (SCD) and account for at least 50% of the mortality of patients with ischemic heart failure. Since ischemia is the trigger for ventricular arrhythmias in most cases coronary artery bypass graft surgery (CABG) should be effective in reducing recurrent episodes of SCD. In a prospective study, we evaluated the recordings of implantable cardioverter defibrillators (ICD) in patients who had experienced out of hospital cardiac arrest. 64 patients had ICD implantation alone and 11 patients underwent combined ICD implantation and CABG-surgery respectively. ICD recordings were read every 3 months and for each time period the number of recurrent episodes of ventricular tachycardia (VT) was noted. Patients in the surgically treated group had an average of one episode of VT per patient as compared to 2, 7 episodes in the non-surgical group at three month follow-up. This difference was observed during the following months as well. However, at no time (up to 18 months of follow-up) the difference was statistical significant. No patient died in the surgically treated group as compared to a 3.1% mortality in the medically treated group (n.s.).

Although we could not demonstrate a significant difference between the two groups, patients in the surgically treated group had less episodes of recurrent VT than in the medically treated group. We conclude that survivors of SCD presenting with multivessel coronary artery disease (CAD) should undergo coronary artery bypass grafting to prevent myocardial ischemia as the triggering event for lethal ventricular arrhythmias.