Borlaug Barry A, Lam Carolyn S P, Roger Véronique L, Rodeheffer Richard J, Redfield Margaret M
Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic Rochester, Minnesota.
J Am Coll Cardiol. 2009 Jul 28;54(5):410-8. doi: 10.1016/j.jacc.2009.05.013.
We sought to compare left ventricular (LV) systolic stiffness and contractility in normal subjects, hypertensive patients without heart failure, and patients with heart failure and preserved ejection fraction (HFpEF) and to determine whether LV systolic stiffness or myocardial contractility is associated with the rate of mortality in patients with HFpEF.
Arterial load is increased in patients with hypertension and is matched by increased end-systolic LV stiffness (ventricular-arterial coupling). Increased end-systolic LV stiffness may be mediated by enhanced myocardial contractility or processes that increase passive myocardial stiffness.
Healthy control patients (n = 617), hypertensive patients (no heart failure, n = 719), and patients with HFpEF (n = 244, 96% hypertensive) underwent echo-Doppler characterization of arterial (Ea) and LV end-systolic (Ees) stiffness (elastance), ventricular-arterial coupling (Ea/Ees ratio), and chamber-level and myocardial contractility (stress-corrected midwall shortening).
We found that Ea and Ees were similarly increased in hypertensive patients with or without HFpEF compared with control patients, but ventricular-arterial coupling was similar across groups. In hypertensive patients, increased Ees was associated with enhanced chamber-level and myocardial contractility, whereas in patients with HFpEF, chamber and myocardial contractility were depressed compared with both hypertensive and control patients. Group differences persisted after adjusting for geometry. In patients with HFpEF, impaired myocardial contractility (but not Ees) was associated with increased age-adjusted mortality.
Although arterial load is increased and matched by increased LV systolic stiffness in hypertensive patients with or without HFpEF, the mechanisms of systolic LV stiffening differ substantially. These data suggest that myocardial contractility increases to match arterial load in asymptomatic hypertensive heart disease, but that progression to HFpEF may be mediated by processes that simultaneously impair myocardial contractility and increase passive myocardial stiffness.
我们试图比较正常受试者、无心力衰竭的高血压患者以及射血分数保留的心力衰竭(HFpEF)患者的左心室(LV)收缩期僵硬度和收缩性,并确定LV收缩期僵硬度或心肌收缩性是否与HFpEF患者的死亡率相关。
高血压患者的动脉负荷增加,同时左心室收缩末期僵硬度增加(心室-动脉耦联)。左心室收缩末期僵硬度增加可能由心肌收缩性增强或增加被动心肌僵硬度的过程介导。
健康对照患者(n = 617)、高血压患者(无心力衰竭,n = 719)和HFpEF患者(n = 244,96%为高血压患者)接受了动脉(Ea)和左心室收缩末期(Ees)僵硬度(弹性)、心室-动脉耦联(Ea/Ees比值)以及心腔水平和心肌收缩性(应力校正的室壁中层缩短)的超声多普勒特征分析。
我们发现,与对照患者相比,有或无HFpEF的高血压患者的Ea和Ees同样增加,但各组间心室-动脉耦联相似。在高血压患者中,Ees增加与心腔水平和心肌收缩性增强相关,而在HFpEF患者中,与高血压患者和对照患者相比,心腔和心肌收缩性均降低。调整几何形状后,组间差异仍然存在。在HFpEF患者中,心肌收缩性受损(而非Ees)与年龄校正死亡率增加相关。
尽管有或无HFpEF的高血压患者的动脉负荷增加且左心室收缩期僵硬度相应增加,但左心室收缩期僵硬的机制有很大不同。这些数据表明,在无症状性高血压性心脏病中,心肌收缩性增加以匹配动脉负荷,但进展为HFpEF可能由同时损害心肌收缩性和增加被动心肌僵硬度的过程介导。