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Pulmonary Atresia and Intact Ventricular Septum

  • Mazeni AlwiEmail author
  • Zaheer Ahmad
Chapter
  • 483 Downloads

Abstract

Patients with pulmonary atresia with intact ventricular septum present with diverse right ventricular size and morphology. RV-coronary connections are more likely to be seen in those with small right ventricle (RV). The most suitable patients for valve perforation and balloon dilation are those with imperforate membranous atresia and well-developed infundibular and main pulmonary artery. The RV may be tripartite but quite commonly bipartite where the apical part is obliterated by muscles. The procedure is more challenging in those with narrow infundibulum with small pulmonary annulus and thick valve tissue, where the RV is often small and coronary communications may be present. The risk of perforation outside the heart and cardiac tamponade is higher. Exclusion criteria for this procedure are patients with very severe tricuspid regurgitation due to tricuspid valve dysplasia and those with RV-dependent coronary circulation and muscular atresia of the infundibulum. Major complications are cardiac tamponade and myocardial infarction in patients with coronary abnormalities.

Keywords

Valve perforation and balloon dilation Membranous atresia Cardiac tamponade RV-coronary connections RV-dependent coronary circulation Tricuspid regurgitation Tricuspid valve dysplasia 

Supplementary material

Video 1

A patient with a small but tripartite RV and membranous atresia who would otherwise be suitable for valve perforation and balloon dilation but the coronary circulation is thought to be RV dependent. The contrast in the apical part is less dense compared to the inlet and infundibulum indicating hypertrophied muscles. A dilated LAD fills retrogradely from the RV apex, seen to the left of the spine on the AP view and on the anterior border of the cardiac silhouette on the lateral view, red arrows (Video 1: shots 1 and 2). Aortic root angiogram in RAO view shows severe stenosis of LCA at the ostium (Video 1: shot 3). Abbreviations: RV right ventricle, TV tricuspid valve, LCA left coronary artery, MPA main pulmonary artery, RVOT RV outflow tract, PAIVS pulmonary atresia intact ventricular septum, TR tricuspid regurgitation, RA right atrium, PDA patent ductus arteriosus, LAD left anterior descending, AP anteroposterior, RAO right anterior oblique, LAO left anterior oblique (PPTX 620 kb)

Video 2

Profiling the RVOT, valve annulus, pulmonary valve tissue and main pulmonary artery. In the lateral projection, with the tip of JR catheter positioned underneath the valve and a pigtail catheter opposite the PDA in the aorta, a near-simultaneous contrast injection is done to opacify the ROVT and the MPA to assess the characteristics of the infundibulum, the valve annulus size, thickness of the valve tissue and the MPA size and sinuses relative to the RVOT. The most favourable cases have wide, smooth-walled infundibulum with a thin valve membrane which is cupped over by the well-developed sinuses of the MPA as in the first video. The risk of perforating outside the heart is small. In the second video, the pulmonary valve is a thick plate, suggesting that a higher dose of energy may be required for perforation. Nevertheless the valve annulus and MPA are of good size although the sinuses are poorly developed. Abbreviations: PDA patent ductus arteriosus, RVOT right ventricular outflow tract, MPA main pulmonary artery, TR tricuspid regurgitation, RV right ventricle, RF radio frequency, RCA right coronary artery, LCA left coronary artery (PPTX 1150 kb)

Video 3

Series of videos demonstrating valve perforation with radio frequency wire followed by step-wise balloon dilation. Aortic angiography opposite the PDA confirms that the tip of 5F JR catheter is abutting the centre of the imperforate valve, with the MPA and sinuses cupping over the RVOT. On the AP view, the pigtail catheter position corresponds to the central part of the MPA. This serves as a guide for directing the RF wire. The RF wire (Cereblate, Osypka AG, 79618 Rheinfelden, Germany) is pushed forwards firmly but without exerting too much force (Video 3: shot 3) perforating the valve smoothly. In most cases the wire should go slightly rightwards (Video 3: shot 4) towards the pigtail catheter suggesting that it is within the MPA lumen. This is confirmed by aortic angiography following valve perforation (Video 3: shots 1 and 2). Alongside the RF wire, a straight-tipped coronary guidewire of moderate stiffness (Choice PT Extra Support, Boston Scientific, Marlborough MA01752, USA) is passed into the pulmonary artery, again confirmed by angiography (Video 3: shot 3). The valve is dilated initially using a 3.0 mm coronary balloon followed by an 8.0 mm balloon (Tyshak mini, Numed Canada, Cornwall ON K6J 1G3) (Video 3: shots 4 and 5). Abbreviations: PDA patent ductus arteriosus, RVOT right ventricular outflow tract, AP anteroposterior, MPA main pulmonary artery, RF radiofrequency (PPTX 4601 kb)

Video 4

Use of coronary wire with stiffer tip (for chronic total occlusion, CTO wire) for valve perforation as alternative to RF wire in favourable cases. For patients with thin membranous valve and well-developed infundibulum and MPA, a CTO wire may be used as an alternative to RF wire if this is unavailable. However it is not as effective, and the risk of perforation outside the heart is likely to be higher because of the force required. Shots 1–3 in Video 4 demonstrate a successful perforation with a CTO wire (Conquest Pro, Asahi Intecc, Aichi 489-0071, Japan). This same wire was then used for balloon dilation. Unsuccessful perforation with a CTO wire in a patient with a thin membranous valve that appeared suitable (Video 4: shot 1). RF wire at 5 W failed to perforate the valve (Video 4: shot 2). Successful perforation at 10 W (Video 4: shot 3). Abbreviations: MPA main pulmonary artery, CTO chronic total occlusion, RF radio frequency (PPTX 3778 kb)

Video 5

Complications. Perforation outside the heart which may cause tamponade. This complication is more likely to occur in patients with less favourable anatomy, i.e. those with more severe muscular overgrowth and smaller RV cavity. They tend to have small valve annulus with thick valve plate and less well-developed MPA and sinuses. In this patient with bipartite RV, the RVOT and the pulmonary valve annulus are small with thick immobile pulmonary valve plate. The MPA and the sinuses are also relatively small. RV-coronary connections are also present (Video 5: shots 1 and 2). On the lateral view, the RF has perforated on the margin of the valve and into the pericardial space outside the MPA anteriorly (Video 5: shot 3), although on the AP view it appears to be within the MPA lumen (Video 5: shot 4). The JR catheter was repositioned with its tip facing more inferiorly to effect successful perforation into the MPA and RPA lumen (Video 5: shots 5 and 6). Balloon dilation was successfully performed. A small amount of contrast is seen in the pericardial space. Abbreviations: RV right ventricle, RVOT RV outflow tract, MPA main pulmonary artery, RF radio frequency, AP anteroposterior, RPA right pulmonary artery (PPTX 2344 kb)

Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institut Jantung Negara (National Heart Institute), Jalan Tun RazakKuala LumpurMalaysia

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