[Exclusive permanent atrial stimulation. Clinical experience apropos of 65 cases with a follow-up of 1 to 5 years].

The authors report their experience of permanent exclusive atrial pacing in the treatment of sinus node dysfunction in a series of 65 cases with a follow up of 1 to 5 years (average 37.6 months; 2406 patients months), 41 women and 24 men aged 74 +/- 3 years. Sixty one patients were symptomatic. The diagnosis was made from surface ECG recordings in 54 cases (83 p. 100) and after electrophysiological investigation in 11 cases (16 p. 100). Atrioventricular conduction was carefully evaluated before implantation: PR equal to or less than 200 ms, Wenckebach point equal to or greater than 130/min, absence of ventricular pauses longer than 3,000 ms after carotid sinus massage, HV interval equal to or less than 55 ms [measured in 57 cases (87 p. 100)], negative Ajmaline test in 6 patients with intraventricular conduction defects. Performed J-shaped atrial leads with active (66 p. 100) or passive fixations (34 p. 100) were implanted by an endocavitary approach (right subclavian vein in 60 cases: 92 p. 100). There were 3 cases of early lead displacement and one patient developed an elevated threshold of pacing. There were 5 deaths during the follow-up period (3 of cardiovascular origin). The neurological symptoms disappeared in 93 p. 100 of cases. No cases of cardiac failure were observed after permanent pacing. Fifteen patients had documented supraventricular arrhythmias before implantation; 5 patients continued to have the same paroxysmal or permanent arrhythmias but 10 patients had no further recurrences, 8 with and 2 without antiarrhythmic therapy.(ABSTRACT TRUNCATED AT 250 WORDS)