Iwataki Mai, Kim Yun-Jeong, Sun Byung-Joo, Jang Jeong-Yoon, Takeuchi Masaaki, Fukuda Shota, Otani Kyoko, Yoshitani Hidetoshi, Ohe Hisaharu, Kohno Ritsuko, Oginosawa Yasushi, Abe Haruhiko, Levine Robert A, Song Jae-Kwan, Otsuji Yutaka
Second Department of Internal Medicine, University of Occupational and Environmental Health, School of Medicine, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, 807-8555 Japan.
Echocardiography Laboratory, Asan Medical Center, Seoul, Korea.
J Echocardiogr. 2015 Mar;13(1):27-34. doi: 10.1007/s12574-014-0235-z. Epub 2014 Dec 6.
Heart failure (HF) can be caused by left ventricular (LV) pump failure as well as by bradyarrhythmias. Hemodynamic differences between HF by LV pump failure and that by bradyarrhythmia have not been fully investigated. We hypothesized that HF by LV pump failure could be associated with both reduced cardiac output (CO) and increased LV filling pressure due to associated LV diastolic dysfunction, whereas HF by bradyarrhythmia could be associated with reduced CO but only modestly increased LV filling pressure due to the absence of LV diastolic dysfunction.
In 39 patients with HF by LV pump failure (LV ejection fraction <35%), 24 with HF by bradyarrhythmia, and 22 normal controls, LV volume, ejection fraction, stroke volume, left atrial volume, and early diastolic mitral valve flow to tissue annular velocity ratio (E/E') were measured by echocardiography.
Compared to patients with HF by LV pump failure, those with HF by bradyarrhythmia had significantly lower heart rates, less LV dilatation, preserved LV ejection fraction, preserved stroke volume, similarly reduced cardiac index (1.8 ± 0.4 vs. 1.6 ± 0.4 L/min/m(2), n.s.), preserved LV diastolic function (E') (4.4 ± 2.1 vs. 7.1 ± 2.9 cm/s, p < 0.001), less dilated end-systolic LA volume, and preserved E/E' (24 ± 10 vs. 13 ± 7, p < 0.001).
HF by LV pump failure is characterized by both significantly reduced CO and increased LV filling pressure, whereas HF by bradyarrhythmia is characterized by a similar reduction in CO but only modestly increased LV filling pressure.
心力衰竭（HF）可由左心室（LV）泵功能衰竭以及缓慢性心律失常引起。LV泵功能衰竭所致HF与缓慢性心律失常所致HF之间的血流动力学差异尚未得到充分研究。我们推测，LV泵功能衰竭所致HF可能与心输出量（CO）降低以及由于相关的LV舒张功能障碍导致的LV充盈压升高有关，而缓慢性心律失常所致HF可能与CO降低有关，但由于不存在LV舒张功能障碍，LV充盈压仅适度升高。
对39例LV泵功能衰竭所致HF（LV射血分数<35%）患者、24例缓慢性心律失常所致HF患者和22例正常对照者，通过超声心动图测量LV容积、射血分数、每搏量、左心房容积以及舒张早期二尖瓣血流与组织环速度比值（E/E'）。
与LV泵功能衰竭所致HF患者相比，缓慢性心律失常所致HF患者心率显著降低，LV扩张程度较小，LV射血分数保留，每搏量保留，心脏指数降低程度相似（1.8±0.4 vs. 1.6±0.4 L/min/m²，无显著差异），LV舒张功能（E'）保留（4.4±2.1 vs. 7.1±2.9 cm/s，p<0.001），收缩末期LA容积扩张程度较小，E/E'保留（24±10 vs. 13±7，p<0.001）。
LV泵功能衰竭所致HF的特征是CO显著降低和LV充盈压升高；而缓慢性心律失常所致HF的特征是CO类似程度降低，但LV充盈压仅适度升高。
