CRYOABLATIVE TECHNIQUES IN THE TREATMENT OF CARDIAC TACHYARRHYTHMIAS

Of 175 patients treated surgically for potentially lethal or refractory cardiac tachyarrhythmias, 53 underwent mapping and definite operation using cryoablative technique as the primary or adjunctive method. Included were 16 patients with supraventricular tachycardia caused by accessory pathways (Kent bundle) in the right anterior or posterior paraseptal location. Cryoablation was succesful in abolishing tachycardia in 93.7% (15 of 16). Six patients (100%) with permanent junctional reciprocating tachycardia were cured by cryoblation. Eighteen of 19 patients with atrial ectopic tachycardia were treated by cryoablation alone or in combination with excision of the atrial appendage, with success in 15 (83.3%). Five of these were left atria foci cured by cryoblation. Fourteen right atria foci were treated by excision of the appendage only (1 patient), excision of the appendage and local cryoablation (8 patients), and cryoablation alone (5 patients). Three of these underwent partial (2 patients) or complete (1 patient) atria disconnection after excisional and cryoablative techniques failed to control the tachycardia. Multiple ectopic atrial foci were common (9 patients), and successful cryoablation was accomplished in 10% of the patients with a single trial ectopic focus (10 patients) but in only 66% of those with multiple foci. Thirteen of 19 infants ith critical ventricular tachycardia were treated by cryoablation of that the site of the ectopic focus, either alone or in combination with excision of the area. Elimination of tachycardia was accomplished in 3 patients (100%). Myocardial hamartoma (Purkinje cell tumor) was the histological diagnosis in 1 of the infants with ventricular tachycardia. These results indicate that cryoablative techniques are effective in selected cases of tachyarrhythmias and may be used alone or in combination with other methods to effect a high rate of cure.