Cholinesterase inhibition reduces arrhythmias in asymptomatic Chagas disease

Introduction Parasympathetic dysfunction may play a role in the genesis of arrhythmias in Chagas disease. Aim This study evaluates the acute effects of pyridostigmine (PYR), a reversible cholinesterase inhibitor, on the occurrence of arrhythmias in patients with Chagas cardiac disease. Method Following a double-blind, randomized, placebo-controlled, cross-over protocol, 17 patients (age 50±2 years) with Chagas cardiac disease type B underwent 24-hour Holter recordings after oral administration of either pyridostigmine bromide (45 mg, 3 times/day) or placebo (PLA). Results Pyridostigmine reduced the 24-h incidence [median (25%-75%)] of premature ventricular beats - PLA: 2998 (1920-4870), PYR: 2359 (940-3253), P=0.044; ventricular couplets - PLA: 84 (15-159), PYR: 33 (6-94), P=0.046. Although the total number of non-sustained ventricular tachycardia in the entire group was not different (P=0.19) between PLA [1 (0-8)] and PYR [0 (0-4)], there were fewer episodes under PYR in 72% of the patients presenting this type of arrhythmia (p= 0.033). Conclusion Acute administration of pyridostigmine reduced the incidence of non-sustained ventricular arrhythmias in patients with Chagas cardiac disease. Further studies that address the use of pyridostigmine by patients with Chagas cardiac disease under a more prolonged follow-up are warranted. This article is protected by copyright. All rights reserved.