Comparison of frequency of recurrent syncope after beta-blocker therapy versus conservative management for patients with vasovagal syncope

FreeText:The diagnosis of VVS was confirmed by a consulting electrophysiologist who reviewed the patient's clinical presentation and response to tilt-table testing. Conservative therapy is defined as patient education, avoidance of dehydration, and no pharmacologic therapy. All patients receive a consultation and educational pamphlet after syncope evaluation and confirmation of diagnosis. For patients with VVS, pathophysiologic mechanisms, warning symptoms, and techniques of preventing and aborting VVS are discussed in the educational material. Demographic and clinical data were obtained retrospectively from a centralized system of records from patients who underwent evaluation of syncope. Follow-up was conducted prospectively with a standardized survey. The end point was defined as recurrence of syncope. Recurrence of syncope was estimated by the Kaplan-Meier method in patients treated with beta blockers and in conservatively treated controls.

AdverseEffects:No adverse events were mentioned.

AuthorsConclusions:We conclude that recurrent syncope was more frequent in patients treated with beta blockers than in those treated conservatively. Our observation challenge the usefulness of "routine" beta-blocker therapy for VVS.

TypeofStudy:Retrospective study comparing frequency of recurrent syncope after beta-blocker (Visken, metoprolol, atenolol or propranolol) therapy versus conservative management for patients with vasovagal syncope (VVS).

Indications:1 patient with vasovagal syncope. Coexisting diseases were coronary artery disease n=19, acute myocardial infarction n=21, diabetes mellitus n=7, chronic obstructive pulmonary disease n=6, chronic renal failure n=3, cancer n=22, sinus bradycardia n=17, right bundle branch block n=5, and left bundle branch block n=5.

Patients:238 patients. Beta blocker group: n=163, 65 men and 98 women, age was 48 ± 25 years. Visken: n=1, metoprolol: n=78, atenolol: n=55 and propranolol: n=30. Mean follow up was 19 ± 13 months. Conservative management group: n=75, 38 men and 37 women, age was 58 ± 22 years. Mean follow up was 22 ± 13 months.

DosageDuration:Dosage and duration not stated.

Results:Recurrent syncopal episodes occurred in 47/163 patients (29%) treated with beta blockers and 15/75 controls (20%) (RR 1.75, 95% CI 0.98 to 3.13, p = 0.056). The probability of survival free of syncope at 2 years, as shown by Kaplan-Meier curve analyses, was 65% for patients treated with beta blockers and 80% for controls (p = 0.056). Predictors of recurrent syncope were analyzed in a multivariate model. The positive predictors were ≥ 5 previous syncopal episodes, the presence of vertigo upon recovery, and the presence of co-morbid conditions.