Surgery for supraventricular tachycardia (SVT).

All forms of supraventricular tachycardia (SVT) are now potentially curable by surgery and we believe that patients should be offered surgery as an initial therapeutic option. At Westmead Hospital, 311 patients have undergone surgery for SVT, 13 having AV node ablation, a procedure now rarely performed, and 298 have had attempts at curative surgery. One hundred and ninety-nine patients were diagnosed primarily as having a Wolff-Parkinson-White syndrome (WPW) and 139 had free wall or anterior septal connections with a clinical cure rate of 98.0%. The failures were entirely due to unrecognised posterior septal connections. Sixty patients had primarily posterior septal connections with a clinical cure rate of 96%. Atrioventricular junctional re-entry tachycardia may now be cured, probably by dividing an extra nodal His-to-atrial connection. Seventy-eight patients have undergone surgery with a clinical cure rate of 92%. Fifteen patients with right atrial tachycardias, 4 patients with nodo-ventricular fibres and 2 with incessant AV tachycardia have undergone surgery. The overall clinical cure rate for all patients is 95% and 92% at late electro-physiological study (EPS).

Accessory mitral valve tissue causing left ventricular outflow tract obstruction.

Although left ventricular outflow tract obstruction is commonly associated with congenitally corrected transposition of the great vessels, this obstruction is seldom caused by accessory mitral valve tissue. Three cases in which accessory mitral valve tissue caused left ventricular outflow tract obstruction in children are described. Two had congenitally corrected transposition and one had normally connected great vessels. The accessory leaflet tissue, which was identified by echocardiography and angiography, was attached by chordae tendineae to normally sited papillary muscles and herniated into the left ventricular outflow tract during systole. Operation was successful in these patients. The accessory valve tissue was excised via an arteriotomy in the great vessel that arose from the left ventricle. The obstructive tissue was excised close to its peripheral attachments in the outflow tract and its chordae tendineae were divided. Resection was performed without injury to the abnormally placed conduction system or to the normal valve structures.

Complications of ascending aortic intraaortic balloon pump cannulation.

Choice of a route of cannulation for intraaortic balloon counterpulsation during cardiopulmonary bypass is related to accessibility. In those patients in whom it is impossible to pass the intraaortic balloon pump (IABP) into the common femoral artery, ascending aortic cannulation is a rapid and direct method of insertion. Eight patients are described in whom ascending aortic IABP cannulation was undertaken to enable weaning from cardiopulmonary bypass after cardiac surgical procedures. The following problems were encountered: graft infection, aberrant cannulation of the left subclavian artery, left coronary artery embolism, and inability to close the sternum due to mechanical tamponade. A technique is described for insertion of the IABP using a polytetrafluoroethylene (Impra) graft and closed-chest decannulation. Although considerable morbidity and mortality are associated with ascending aortic cannulation, it is simple, fast, and effective, and should be considered for all patients requiring postoperative IABP support in whom peripheral vascular disease makes access difficult.