Hedayati Nasim, Sherwood J Timothy, Schomisch Steve J, Carino Joseph L, Cmolik Brian L
University Hospitals of Cleveland, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106-5011, USA.
J Thorac Cardiovasc Surg. 2002 Jun;123(6):1067-73. doi: 10.1067/mtc.2002.121682.
Aortomyoplasty is an experimental surgical procedure in which the latissimus dorsi muscle is wrapped around the thoracic aorta and stimulated to contract during diastole, providing diastolic counterpulsation. We hypothesized that aortomyoplasty could improve cardiac function in a chronic ischemic heart failure model, similar to the improvement seen with the intra-aortic balloon pump.
Six dogs (25-30 kg) successfully underwent aortomyoplasty followed by serial coronary microembolization. Ejection fraction decreased from 63.5% to 36.5%. Two weeks after the final microembolization, the muscle was conditioned for 4 months to achieve fatigue resistance. One year after aortomyoplasty, hemodynamic studies during 1 hour of aortomyoplasty and 1 hour of intra-aortic balloon counterpulsation determined mean diastolic aortic pressure, peak left ventricular pressure, and endocardial viability ratio for assisted and unassisted beats. Cardiac output, stroke volume, and parameters of cardiac function were also measured.
Endocardial viability ratio increased by 23.8% +/- 7.9% (P =.001) with aortomyoplasty counterpulsation and by 22.7% +/- 12.9% (P =.021) with the intra-aortic balloon pump. Both aortomyoplasty and the intra-aortic balloon pump significantly increased mean diastolic aortic pressure and reduced peak left ventricular pressure. Improvements in cardiac function with aortomyoplasty and the intra-aortic balloon pump were similar. Cardiac output increased from 2.61 +/- 0.88 to 3.07 +/- 1.06 L/min (P =.006), and index of afterload decreased from 5.4 +/- 1.4 to 4.8 +/- 1.4 mm Hg/mL (P =.02) during 1 hour of aortomyoplasty counterpulsation.
One year after the procedure, aortomyoplasty counterpulsation provided diastolic augmentation and improved cardiac performance similar to the improvement provided by the intra-aortic balloon pump in a chronic ischemic heart failure model. Aortomyoplasty has the potential to benefit patients with ischemic heart disease refractory to current therapies.
主动脉肌成形术是一种实验性外科手术，即背阔肌环绕胸主动脉并在舒张期受刺激收缩，从而提供舒张期反搏。我们假设主动脉肌成形术能够改善慢性缺血性心力衰竭模型的心脏功能，类似于主动脉内球囊泵所带来的改善效果。
6只犬（体重25 - 30千克）成功接受主动脉肌成形术，随后进行系列冠状动脉微栓塞。射血分数从63.5%降至36.5%。在最后一次微栓塞后两周，对肌肉进行4个月的适应性训练以达到抗疲劳能力。主动脉肌成形术一年后，在主动脉肌成形术1小时和主动脉内球囊反搏1小时期间进行血流动力学研究，测定辅助搏动和非辅助搏动的平均舒张期主动脉压、左心室峰值压力及心内膜存活比率。还测量了心输出量、每搏输出量及心脏功能参数。
主动脉肌成形术反搏使心内膜存活比率增加23.8%±7.9%（P = 0.001），主动脉内球囊泵使其增加22.7%±12.9%（P = 0.021）。主动脉肌成形术和主动脉内球囊泵均显著提高平均舒张期主动脉压并降低左心室峰值压力。主动脉肌成形术和主动脉内球囊泵对心脏功能的改善相似。在主动脉肌成形术反搏1小时期间，心输出量从2.61±0.88升/分钟增加至3.07±1.06升/分钟（P = 0.006），后负荷指数从5.4±1.4降至4.8±1.4毫米汞柱/毫升（P = 0.02）。
在该手术一年后，主动脉肌成形术反搏在慢性缺血性心力衰竭模型中提供了舒张期增强作用并改善了心脏性能，类似于主动脉内球囊泵所带来的改善。主动脉肌成形术有可能使对当前治疗难治的缺血性心脏病患者受益。
