Impact of myocardial fibrosis on exercise capacity in heart failure with preserved ejection fraction

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K07622
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Hokkaido University
• Principal Investigator: Iwano Hiroyuki 北海道大学, 医学研究院, 客員研究員 (50622354)
• Co-Investigator(Kenkyū-buntansha): 横田 卓 北海道大学, 大学病院, 特任講師 (90374321) ; 納谷 昌直 北海道大学, 大学病院, 講師 (20455637) ; 安斉 俊久 北海道大学, 医学研究院, 教授 (60232089)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 心不全 / 運動負荷試験 / 心エコー図検査

Outline of Final Research Achievements

Impaired exercise tolerance is a major symptom of heart failure, and heart failure with preserved left ventricular ejection fraction (HFpEF) has a phenotype with no apparent organic abnormalities in the left ventricle. Because the determinants of tolerance in this etiology are not clear, the mechanism of decreased exercise tolerance in this pathological condition was investigated using exercise echocardiography and cardiac MRI.
Cardiopulmonary exercise testing, exercise echocardiography, and contrasted-enhanced cardiac MRI were performed in 49 HFpEF patients without left ventricular hypertrophy, and the determinants of exercise tolerance were examined. As a result, exercise-induced pulmonary hypertension and impaired right ventricular-pulmonary artery coupling, rather than LV diastolic dysfunction, were found to be associated with exercise tolerance.

Free Research Field

心臓超音波検査

Academic Significance and Societal Importance of the Research Achievements

左室肥大のないHFpEFにおける運動耐容能低下の意義を明らかにできたことで、発症早期あるいは直前のHFpEFにおける治療ターゲットを提示することができたものと考えられる。
また、心臓MRIにおける心筋線維化指標が、実際の左室拡張障害と関連しなかった原因は、今後さらなる検討により明らかにされることが期待される。