JACC: Basic to Translational Science (Nov 2019)

Electrophysiological and Contractile Effects of Disopyramide in Patients With Obstructive Hypertrophic Cardiomyopathy

  • Raffaele Coppini, MD, PhD,
  • Cecilia Ferrantini, MD, PhD,
  • Josè Manuel Pioner, PhD,
  • Lorenzo Santini, MS,
  • Zhinuo J. Wang, PhD,
  • Chiara Palandri, MS,
  • Marina Scardigli, PhD,
  • Giulia Vitale, MS,
  • Leonardo Sacconi, PhD,
  • Pierluigi Stefàno, MD,
  • Laura Flink, MD,
  • Katherine Riedy, MD,
  • Francesco Saverio Pavone, PhD,
  • Elisabetta Cerbai, PhD,
  • Corrado Poggesi, MD,
  • Alessandro Mugelli, MD,
  • Alfonso Bueno-Orovio, PhD,
  • Iacopo Olivotto, MD,
  • Mark V. Sherrid, MD

Journal volume & issue
Vol. 4, no. 7
pp. 795 – 813

Abstract

Read online

Summary: Disopyramide is effective and safe in patients with obstructive hypertrophic cardiomyopathy. However, its cellular and molecular mechanisms of action are unknown. We tested disopyramide in cardiomyocytes from the septum of surgical myectomy patients: disopyramide inhibits multiple ion channels, leading to lower Ca transients and force, and shortens action potentials, thus reducing cellular arrhythmias. The electrophysiological profile of disopyramide explains the efficient reduction of outflow gradients but also the limited prolongation of the QT interval and the absence of arrhythmic side effects observed in 39 disopyramide-treated patients. In conclusion, our results support the idea that disopyramide is safe for outpatient use in obstructive patients. Key Words: action potentials, arrhythmias, diastolic dysfunction, hypertrophic cardiomyopathy, QT interval, safety