Smalling R W, Sweeney M, Lachterman B, Hess M J, Morris R, Anderson H V, Heibig J, Li G, Willerson J T, Frazier H
Department of Internal Medicine, University of Texas Medical School at Houston 77030.
J Am Coll Cardiol. 1994 Mar 1;23(3):637-44. doi: 10.1016/0735-1097(94)90748-x.
The purpose of this study was to test the hypothesis that transvalvular left ventricular assistance would support the circulation in patients with cardiogenic shock secondary to acute myocardial infarction and allow recovery of function in patients with a reversibly damaged (stunned) left ventricle.
Cardiogenic shock occurs in 7.5% of patients presenting with acute myocardial infarction, resulting in survival of only 20%. Despite the use of aggressive interventional therapy in patients with shock secondary to anterior myocardial infarction, survival remains as low as 33%.
We studied 11 patients with acute myocardial infarction and cardiogenic shock, as defined by a cardiac index < 2 liters/min per m2, pulmonary capillary wedge pressure > 18 mm Hg and systolic blood pressure < 90 mm Hg during positive inotropic therapy. Patients were 57 +/- 13 years old (mean +/- SD) and had a mean left ventricular ejection fraction of 25 +/- 11%, mean arterial pressure of 69 +/- 13 mm Hg and mean cardiac index of 1.6 +/- 0.4 liters/min per m2 on admission to the study.
During the 1st 24 h of left ventricular assistance, pulmonary capillary wedge pressure decreased from 26 +/- 4 to 16 +/- 4 mm Hg (p = 0.01), cardiac index increased from 1.6 +/- 0.4 to 2.4 +/- 0.4 liters/min per m2, and the dopamine hydrochloride dose decreased from 51 +/- 92 to 18 +/- 12 micrograms/kg body weight per min. In survivors, cardiac index improved to 3.2 +/- 0.5 liters/min per m2 (p = 0.01), and left ventricular ejection fraction improved to 34 +/- 5% (p < 0.05). The overall survival in the study group was 4 (36%) of 11 patients (95% confidence interval [CI] 8% to 65%), and 4 (66%) of 6 patients (95% CI 29% to 100%) with a Q wave anterior myocardial infarction survived.
Transvalvular left ventricular support during cardiogenic shock complicating acute myocardial infarction is feasible and results in significant hemodynamic and functional improvement.
本研究旨在验证以下假设，即经瓣膜左心室辅助可支持急性心肌梗死继发心源性休克患者的循环，并使左心室可逆性受损（顿抑）患者的功能得以恢复。
7.5%的急性心肌梗死患者会发生心源性休克，生存率仅为20%。尽管对前壁心肌梗死继发休克的患者采用了积极的介入治疗，但其生存率仍低至33%。
我们研究了11例急性心肌梗死并心源性休克患者，心源性休克的定义为在正性肌力治疗期间心脏指数<2升/分钟/平方米、肺毛细血管楔压>18毫米汞柱且收缩压<90毫米汞柱。患者年龄为57±13岁（均值±标准差），研究入组时左心室射血分数均值为25±11%，平均动脉压为69±13毫米汞柱，心脏指数均值为1.6±0.4升/分钟/平方米。
在左心室辅助的最初24小时内，肺毛细血管楔压从26±4降至16±4毫米汞柱（p = 0.01），心脏指数从1.6±0.4升至2.4±0.4升/分钟/平方米，盐酸多巴胺剂量从51±92降至18±12微克/千克体重/分钟。存活患者的心脏指数改善至3.2±0.5升/分钟/平方米（p = 0.01），左心室射血分数改善至34±5%（p<0.05）。研究组11例患者中有4例（36%）存活（95%置信区间[CI]8%至65%），6例Q波前壁心肌梗死患者中有4例（66%）存活（95%CI 29%至100%）。
急性心肌梗死并发心源性休克时经瓣膜左心室支持是可行的，并可导致显著的血流动力学和功能改善。
