[Deciding about pacing mode in sinus node dysfunction: should carotid sinus massage be performed and in which circumstances?]. / Decisão do modo de pacing na doença do nódulo sinusal: será a massagem do seio carotídeo pertinente e em que circunstâncias?

OBJECTIVE: To state the incidence of carotid sinus syndrome (CSS) with atrioventricular node manifestation in patients with sinus node dysfunction (SND) and indication for a definitive pacemaker (PM), we propose a new protocol between atrial pacing AAI and double chamber DDD. POPULATION AND METHODS: 69 patients (PTS) (male 71%), median age 65 +/- 10 years, with SND (normal PQ and no intraventricular conduction defect), that had a PM implant following the protocol that included carotid sinus massage for the pacing decision, were followed prospectively between December 1995 and November 1999. During the protocol we implanted DDD PM in PTS with Wenckebach less than 130 or Wenckebach equal/over 130 and CSS. At least, in PTS with Wenckebach equal/over 130 and no CSS we implanted AAI PM. The follow-up was between 4 months and 4 years, with clinical evaluation in the first and fourth months and then half yearly, with carotid sinus massage in the first evaluation. RESULTS: About 1/4 of the 69 patients followed had SND without carotid sinus syndrome, or atrioventricular node repercussion; the SND involved the atrioventricular node in 56% of the patients, and there was a relation between the SND and carotid sinus syndrome in 18.8%. The follow-up revealed, in all patients, a complete remission of the symptoms, and when we repeated the carotid sinus massage in the first evaluation, there was a response like in the surgery room, in all patients. CONCLUSIONS: There is a significant number of patients with SND and carotid sinus syndrome. The carotid sinus massage performed in the surgery room does not influence the test sensitivity and specificity in the diagnosis of carotid sinus syndrome. The authors think that carotid sinus massage should be considered in the protocol that defines the pacing mode, in patients with SND, and that influence the choice of pacemaker in 18.8% of patients.

[Transesophageal echocardiography in electrical cardioversion: Is it possible to predict conversion to sinus rhythm?]. / Ecocardiografia transesofágica precardioversão eléctrica: será possível predizer a conversão a ritmo sinusal.

Due to its ability to safely exclude thrombi, transesophageal echocardiography (TEE) is now routinely performed in patients proposed for electrical cardioversion. However, what is the value of TEE in predicting conversion to sinus rhythm in patients with atrial fibrillation (AF)? To answer this question, TEE was performed in 21 patients with chronic AF before elective cardioversion. Patients were divided in two groups according to the outcome of cardioversion: Group A--Restoration of sinus rhythm achieved: Group B--atrial fibrillation persisted. The echocardiographic variables used to compare both groups were 1--Left Atrial size; 2--Left Atrial Appendage (LAA) systolic and diastolic dimensions; 3--LAA emptying and filling velocities; 4--LAA emptying fraction; 5--Presence of LAA spontaneous contrast. The clinical variable evaluated was 6--therapy with oral amiodarone for more than 2 weeks (> or = 200 mg/day). The results of this study showed that patients with smaller LA, adequately treated with amiodarone and with higher LAA emptying and filling velocities, have the greatest probability of conversion to sinus rhythm.