TRANSVENOUS DEFIBRILLATOR IMPLANTATION IN PATIENTS WITH PERSISTENT LEFT SUPERIOR VENA-CAVA AND RIGHT SUPERIOR VENA-CAVA ATRESIA

In this report a transvenous cardioverter defibrillator implantation i s described in two patients with a persistent left-sided superior vena cava and right SVC atresia. In the first case, manoeuvring of the gui de wire inserted through the left subclavian vein into the SVC proved impossible, revealing a left SVC originating from the left brachioceph alic vein with an acute corner. Changing the side of implantation and inserting a CPI Endotak catheter through the right subclavian vein, th e lead was easily advanced through the left SVC into the coronary sinu s and then into the right atrium with the tip abutting the lateral atr ial wall. Subsequent manoeuvres allowed passage of the tip of the cath eter into the right ventricular apex with the proximal defibrillation coil of the Endotak lead in the low left SVC, with its distal limit at the junction with the coronary sinus. A biphasic waveform single path way RV --> left SVC successfully defibrillated with a stored energy of 5 J. In the second patient, implantation of a transvenous Medtronic s ystem was possible from a left infraclavicular approach. A tripolar RV coil was inserted into the right ventricle via the persistent left SV C and contiguous coronary sinus. Because of the acute angle required t o enter the RV in this second case, the RV lead was looped in the righ t atrium in order to enter the RV in a satisfactory, albeit atypical R V location. This patient was successfully defibrillated with a 5 J mon ophasic waveform delivered between the RV coil, a CS/left SVC coil, an d a subcutaneous patch. In conclusion, both of these patients illustra te the ability to use transvenous ICDs successfully in patients with p ersistent left superior vena cava although the implantation technique deviates substantially from traditional methods.