Monophasic action potential duration alternans after abrupt shortening of the cardiac cycle in humans

• Main Authors: Kazumasa Sonoda, MD, Ichiro Watanabe, MD, Yasuo Okumura, MD, Naoko Sasaki, MD, Rikitake Kogawa, MD, Keiko Takahashi, MD, Hiroaki Mano, MD, Masayoshi Kofune, MD, Kimie Ohkubo, MD, Toshiko Nakai, MD, Satoshi Kunimoto, MD, Atsushi Hirayama, MD
• Format: Article
• Language: English
• Published: Wiley 2014-06-01
• Series: Journal of Arrhythmia
• Subjects: Monophasic action potential; Electrical alternans; Electrophysiology; Heart; Cardiac arrhythmia
• Online Access: http://www.sciencedirect.com/science/article/pii/S1880427613001051
• ISSN: 1880-4276

Background: Action potential alternans may be important in causing ventricular arrhythmias. Methods and results: We recorded monophasic action potentials from the right ventricular endocardium in patients with persistent atrial fibrillation who underwent internal atrial defibrillation during rapid ventricular pacing. In 3 of 45 patients, monophasic action potential duration alternans was observed at a pacing cycle length ≤350 ms. Conclusion: Action potential alternans is not a rare phenomenon (6.6%) in humans.