Fujimoto Naoki, Onishi Katsuya, Dohi Kaoru, Tanabe Masaki, Kurita Tairo, Takamura Takeshi, Yamada Norikazu, Nobori Tsutomu, Ito Masaaki
Department of Cardiology, Mie University Graduate School of Medicine, 2-175 Edobashi, Tsu, Japan.
Hypertens Res. 2008 Sep;31(9):1727-35. doi: 10.1291/hypres.31.1727.
Diastolic heart failure (DHF) has different underlying pathophysiologic mechanisms. We sought to compare hemodynamic characteristics in DHF patients with or without hypertension. A conductance catheter with microtip-manometer was used to measure left ventricular (LV) function and hemodynamics in 28 DHF patients. After baseline measurements, nitroglycerin was infused to alter the loading condition and the measurements were repeated. At baseline, end-systolic pressure was higher and the time constant of LV relaxation (tau) was longer in hypertensive DHF patients. Patients in hypertensive DHF had lower LV-arterial coupling ratio than those in non-hypertensive DHF. The peak of loading sequence was in early systole in non-hypertensive DHF patients and in late systole in hypertensive DHF patients. Nitroglycerin decreased LV end-systolic pressure and end-diastolic volume in both groups. In non-hypertensive DHF, nitroglycerin significantly reduced stroke volume and shortened tau (59+/-11 vs. 54+/-10 ms, p<0.05) without any changes in the time to peak LV force, effective arterial elastance (E(a)), or LV-arterial coupling ratio. In contrast, in hypertensive DHF patients, nitroglycerin significantly reduced E(a) and shortened the time to peak LV force, resulting in an improved LV-arterial coupling ratio, preserved stroke volume and shortened tau (75+/-14 vs. 62+/-13 ms, p<0.05). In conclusion, LV relaxation was more prolonged in hypertensive DHF patients than non-hypertensive DHF patients, partly because of the different loading sequence. Changing the loading condition by nitroglycerin improved LV systolic and diastolic function in hypertensive DHF patients.
舒张性心力衰竭(DHF)有不同的潜在病理生理机制。我们试图比较有或无高血压的DHF患者的血流动力学特征。使用带有微尖端压力计的导管测量28例DHF患者的左心室(LV)功能和血流动力学。在进行基线测量后,输注硝酸甘油以改变负荷状态并重复测量。在基线时,高血压DHF患者的收缩末期压力较高,左心室舒张时间常数(tau)较长。高血压DHF患者的左心室-动脉耦合比低于非高血压DHF患者。非高血压DHF患者的负荷序列峰值出现在收缩早期,而高血压DHF患者出现在收缩晚期。硝酸甘油可降低两组患者的左心室收缩末期压力和舒张末期容积。在非高血压DHF患者中,硝酸甘油显著降低了每搏输出量并缩短了tau(59±11 vs. 54±10毫秒,p<0.05),而左心室力量峰值时间、有效动脉弹性(E(a))或左心室-动脉耦合比无任何变化。相比之下,在高血压DHF患者中,硝酸甘油显著降低了E(a)并缩短了左心室力量峰值时间,从而改善了左心室-动脉耦合比,保持了每搏输出量并缩短了tau(75±14 vs. 62±13毫秒,p<0.05)。总之,高血压DHF患者的左心室舒张比非高血压DHF患者更延长,部分原因是负荷序列不同。通过硝酸甘油改变负荷状态可改善高血压DHF患者的左心室收缩和舒张功能。