Electrophysiological and Contractile Effects of Disopyramide in Patients With Obstructive Hypertrophic Cardiomyopathy: a Translational Study
Raffaele Coppini, Cecilia Ferrantini, Josè Manuel Pioner, Lorenzo Santini, Zhinuo J. Wang, Chiara Palandri, Marina Scardigli, Giulia Vitale, Leonardo Sacconi, Pierluigi Stefàno, Laura Flink, Katherine Riedy, Francesco Saverio Pavone, Elisabetta Cerbai, Corrado Poggesi, Alessandro Mugelli, Alfonso Bueno-Orovio, Iacopo Olivotto and Mark V. Sherrid
Effects of Disopyramide on AP and Cellular Arrhythmias
(A) Representative superimposed action potentials (AP) at baseline (black traces) and in the presence of disopyramide 5 μmol/l (Diso) (blue traces), elicited at 0.2 Hz (left) and at 1 Hz (right). (B) Action potential duration at 90% of repolarization (APD90%) at baseline (black) and in the presence of disopyramide (blue). (C) Representative action traces at baseline (black traces) and in the presence of disopyramide 5 μmol/l (blue traces), elicited at 0.2 Hz pacing rate. Disopyramide suppresses early afterdepolarizations (EAD) (arrows). (D) Percentage of HCM cardiomyocytes showing at least 2 EAD or delayed afterdepolarizations (DAD) during 3 min of continuous stimulation, at baseline (black) and in the presence of disopyramide (blue). (B,D) Means ± SE from 28 hypertrophic cardiomyopathy cardiomyocytes from 8 patients with hypertrophic cardiomyopathy (ID 3 to 6, 9, and 11 to 13). **0.01 > p > 0.001; ***p < 0.001; linear-mixed models.