Clinical Usefulness of Electrophysiologic Testing in Patients with Ventricular Tachycardia and Chronic Chagasic Cardiomyopathy Treated with Amiodarone or Sotalol

Abstract

In patients with chagasic cardiomyopathy and sustained VT, electrophysiologic testing can predict long-term efficacy of Class III antiarrhythmic drugs. This may help in the selection of patients for implantable cardioverter defibrillator therapy.

Realce Tardio miocárdico por Ressonância Magnética Cardíaca pode identificar risco para Taquicardia Ventricular na Cardiopatia Chagásica Crônica

“…Inducibility had PPV and NPV of 46% and 85% for cardiac mortality, respectively 35 . In another study, inducibility of non-tolerated sustained VT in a patient with CCM after previous impregnation with class III antiarrhythmic drugs (amiodarone and/or sotalol) had PPV and NPV of 49% and 94% for SCD, respectively 36 .…”

Ventricular arrhythmias in Chagas disease

“…Nevertheless, prevention (or reduction of VT burden) is very important in the management of patients with structural heart disease and in particular in chagasic patients, who experience a high frequency of VT/VF recurrence. Leite et al evaluated the effi cacy of antiarrhythmic drug therapy (amiodarone or sotalol) in patients with Chagas cardiomyopathy and observed decreased survival in patients in whom unstable and inducible VT persisted after drug therapy (43) . Note that in this study, ICD implantation was not evaluated; therefore, it is not possible to draw conclusions regarding the indications for its use.…”

I Diretriz Latino-Americana para o Diagnóstico e Tratamento da Cardiopatia Chagásica

“…Arrhythmias in chagasic patients can cause disabling symptoms and SD 70,[203][204][205] . Ventricular arrhythmias are the most frequent and can manifest as isolated ectopies or repetitive forms 206 .…”

“…The SVT is the most common potentially fatal reentry arrhythmia in patients with CCC and segmentary contractile changes, even when the global systolic function is preserved 24,28,[198][199][200] . The arrhythmogenic substrate of that disease is complex, with LV subendocardial, transmural and epicardial scars, which can also affect the right ventricle 200,[201][202][203][204][205][206][207] . Because of that anatomical complexity, the subendocardium or subepicardium (approximately 55% of ventricular tachycardias), or both (transmural circuits), can participate in the reentry circuits of CCC, explaining the presence of episodes of SVT with multiple morphologies 200,201,207 .…”

“…Although ventricular arrhythmias in CD are associated with a higher risk of SD and increased total mortality 70,205,206,208,216 , there is no conclusive evidence that antiarrhythmic drugs have clinically relevant benefits. The most frequent ventricular arrhythmias in chagasic patients are isolated or repetitive ventricular ectopies.…”