Bloqueo aurículoventricular en pacientes en tratamiento con fármacos bradicardizantes. Variables predictoras de la necesidad de marcapasos

Abstract

Atrioventricular block in the presence of bradycardic drugs can be reversible, and pacemaker implantation is controversial. Our objective was to analyze the pacemaker implantation rate in the mid-term, after bradycardic drugs suspension, and to identify predictive factors. We performed a cohort study that included patients attending the emergency department with second degree atrioventricular block type II, 2: 1 or complete in the context of bradycardic drugs. We studied the persistence of atrioventricular block after bradycardic drugs discontinuation, recurrence in patients with atrioventricular drugs resolution, and the predictive variables associated with pacemaker requirement at 3 years. Of 127 patients included (age, 79 [71-83] years), atrioventricular block resolved in 60 (47.2%); among these patients, recurrence occurred during the 24-month median follow-up in 40 (66.6%). Pacemaker implantation was required in 107 patients (84.3%), despite bradycardic drugs discontinuation. On multivariable analysis, the variables associated with pacemaker need at 3 years were heart rate < 35 bpm (OR, 8.12; 95%CI, 1.82-36.17), symptoms other than syncope (OR, 4.09; 95%CI, 1.18-14.13), and wide QRS (OR, 5.65; 95%CI, 1.77-18.04). Concomitant antiarrhythmic treatment was associated with atrioventricular block resolution (OR, 0.12; 95% CI, 0.02-0.66). More than 80% of patients with atrioventricular block secondary to bradycardic drugs require pacemaker implantation despite drug discontinuation. Predictive variables were wide QRS, heart rate < 35 bpm, and clinical presentation other than syncope.