Relation of prognosis in sick sinus syndrome to age, conduction defects and modes of permanent cardiac pacing.

A large population of sick sinus syndrome (SSS) patients was analyzed to determine whether age of patients, presence of conduction disturbances and mode of permanent pacing are related to the occurrence of supraventricular tachyarrhythmias, cerebral embolism and cardiac mortality. Three hundred thirty-nine patients permanently paced (135 AAI, 79 DDD, 125 VVI) because of SSS were followed for a mean period of 5 years (range 2 to 10). Patients were divided into 4 groups according to age (less than 70 or greater than 70 years) and the presence or absence of an associated conduction disturbance. Sixty-eight percent of VVI, 55% of AAI and 40.5% of DDD patients were greater than 70 years of age. In the VVI and DDD groups a conduction disturbance was present in 67 of 204 (33%) patients; conduction disturbances were more common in patients greater than 70 years old (46 of 111, 41%) than in those less than 70 years old (21 of 93,22%). The Wenckebach threshold (greater than 140 beats/min) remained unchanged during the follow-up period in 82% of AAI patients. In 9% of these patients, the Wenckebach threshold showed some degree of deterioration, but only in 2 patients was it less than 100 beats/min (1.5%). Spontaneous second-degree atrioventricular block was observed in 7 patients (5%); it disappeared in 6 of these patients when drug therapy was discontinued.(ABSTRACT TRUNCATED AT 250 WORDS)

[Endocavitary transcatheter electric fulguration as a therapeutic alternative in refractory ventricular tachycardia]. / La folgorazione elettrica endocavitaria transcatetere quale alternativa terapeutica della tachicardia ventricolare refrattaria.

Three patients affected by dilated cardiomyopathy complicated by refractory ventricular tachycardia, with a high risk of sudden cardiac death, underwent transcatheter electric fulguration. The technique was applied transeptally, using the terminals of two catheter electrodes as cathode and anode. These were placed at the right and left ventricular apex, at septal level where the "critical" arrhythmia point had been identified by endocardial mapping. All patients had previously experienced more than one episode of cardiac arrest and had successfully taken several antiarrhythmic drugs. All patients presented variable morphology of ventricular tachycardia (whether spontaneous or induced). In all of them clinical tachycardia was considered as having a left bundle branch block morphology with an earlier activation at low septal level. After treatment, antiarrhythmic therapy (amiodarone 200 mg/day) was continued for all patients, although at a lower dose than before fulguration. One patient has been free from sustained ventricular tachycardia for more than two years after fulguration. In the other patients we observed an early and late arrhythmic recurrence (respectively within 1 and 8 months following fulguration) in spite of antiarrhythmic therapy. The second patient presented no further recurrence after permanent pacemaker implantation. The third patient showed an arrhythmic recurrence, with a different morphology from the previous one, concomitantly with a septic process. This technique does not appear dangerous and may be used, in highly specialized centres, on carefully selected patients as a therapeutic approach after pharmacological therapy and before automatic defibrillator implantation or surgical antiarrhythmic intervention.