湯浅 直紀, 原田 智成, 鏡 和樹, 石井 秀樹, 小保方 優

Naoki YUASA, Tomonari HARADA, Kazuki KAGAMI, Hideki ISHII, Masaru OBOKATA

群馬大学医学部附属病院循環器内科

Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine

キーワード : aging, dyspnea clinics, exercise testing, heart failure, stress echocardiography

左室駆出率の保たれた心不全（heart failure with preserved ejection fraction: HFpEF）は，心不全（heart failure: HF）全体の70％近くを占め，心不全の主要なフェノタイプとなった．このHFpEFの有病率の上昇は「心不全パンデミック」に大きく関与している．心不全は進行性疾患であり，診断の遅れにより臨床転帰が悪化する可能性があることに加えて，ナトリウム‐グルコーストランスポーター2阻害剤やグルカゴン様ペプチド-1受容体アゴニストなどの薬物療法が登場し，HFpEFの適切でタイムリーな診断がより一層重要になった．しかしながら，HFpEFの診断は，うっ血の程度が乏しい患者では難しい場合がある．これは，左室駆出率（ejection fraction: EF）が正常であることに加えて，左室（left ventricular: LV）充満圧が安静時は正常であるのに運動時は異常になるというHFpEFの特徴に関係している．運動負荷心エコー図検査は，運動により誘発する左室充満圧上昇を同定し，HFpEFの診断に有用である．また，運動負荷心エコー図検査は，HFpEF患者のリスク層別化や運動耐容能，心血管系の応答の評価にも役立つ．最近では，原因不明の呼吸困難のある患者から早期のHFpEFを診断し，呼吸困難の原因を精査するための息切れ外来が注目されている．本総論では，HFpEFの診断・評価における運動負荷心エコー図検査の役割を解説する．

Heart failure with preserved ejection fraction （HFpEF） accounts for nearly 70％ of all HF and has become the dominant form of HF. The increased prevalence of HFpEF has contributed to a rise in the number of HF patients, known as the “heart failure pandemic”. In addition to the fact that HF is a progressive disease and a delayed diagnosis may worsen clinical outcomes, the emergence of disease-modifying treatments such as sodium-glucose transporter 2 inhibitors and glucagon-like peptide-1 receptor agonists has made appropriate and timely identification of HFpEF even more important. However, diagnosis of HFpEF remains challenging in patients with a lower degree of congestion. In addition to normal EF, this is related to the fact that left ventricular （LV） filling pressures are often normal at rest but become abnormal during exercise. Exercise stress echocardiography can identify such exercise-induced elevations in LV filling pressures and facilitate the diagnosis of HFpEF. Exercise stress echocardiography may also be useful for risk stratification and assessment of exercise tolerance as well as cardiovascular responses to exercise. Recent attention has focused on dedicated dyspnea clinics to identify early HFpEF among patients with unexplained dyspnea and to investigate the causes of dyspnea. This review discusses the role of exercise stress echocardiography in the diagnosis and evaluation of HFpEF.