Pressure Overload by Pneumonectomy Causes Right Ventricular Lethal Arrhythmias: Analysis by Optical Mapping

2014 Fiscal Year Final Research Report

• Project/Area Number: 24591081
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Circulatory organs internal medicine
• Research Institution: National Defense Medical College
• Principal Investigator: TAKASE Bonpei 防衛医科大学校(医学教育部医学科進学課程及び専門課程、動物実験施設、共同利用研究, 病院, 准教授 (50518214)
• Co-Investigator(Kenkyū-buntansha): ISHIHARA Masayuki 防衛医科大学校, 防衛医学研究センター, 教授 (10508500)
• Co-Investigator(Renkei-kenkyūsha): TANAKA Yoshihiro 防衛医科大学校, 病院, 教授 (50533981)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 肺動脈高血圧 / 致死性不整脈 / 再分極異常

Outline of Final Research Achievements

Right ventricular (RV) pressure overload due to severe pulmonary hypertension (svr-PH > 40 mmHg) sometimes causes lethal arrhythmias, although the mechanisms are unclear. To investigate if RV pressure overload produces RV arryhythmogenic vulnerability, we serially performed optical mapping analysis (OMP) with electrophysiological study (EPS) to the heart excised from pneumonectomy-induced (LP+H) svr-PH rats. Action potential duration dispersion (APDd) and connexin43 (Cx43) expression were measured in RV. LP+H-svr-PH transiently sustained. OMP revealed abnormal RV conduction and increased APDd accompanying ventricular fibrillation/tachycardia (VF/VT) induction by EPS with normal Cx-43 in LP+H -svr-PH. Conclusions; Transiently sustained (>24-hours) svr-PH can cause lethal arrhythmias possibly due to the mechanoelectric transduction not including Cx43degradation.

Free Research Field

心臓病学