Regional effects of aortomyoplasty in acute ischemia.

Abstract

Aortomyoplasty is a technique for achieving autogenous diastolic counterpulsation. This experiment was designed to determine if aortomyoplasty using conditioned latissimus dorsi muscle could improve regional myocardial function during coronary ischemia. Six mongrel dogs underwent a staged operation in which the left latissimus dorsi was conditioned in situ for 4 weeks, then wrapped around the descending aorta and stimulated during diastole with each cardiac contraction. Regional ischemia was caused by occlusion of the left anterior descending coronary artery. Regional function was measured with somomicrometry in the region of ischemia and in a control area. An intraaortic balloon pump was inserted for comparison with aortomyoplasty performance. Coronary artery occlusion caused a significant decrease in the percentage of regional shortening (14.2 +/- 7.9 to -2.2 +/- 4.0; p = 0.001) and thickening (11.9 +/- 4.6 to -5.8 +/- 3.3; p < 0.001). Aortomyoplasty improved regional motion in both percentage shortening (-2.2 +/- 4.0 to 2.3 +/- 3.7; p = 0.008) and thickening (-5.8 +/- 3.3 to 2.8 +/- 1.9; p < 0.001). The intraaortic balloon pump also improved percentage shortening (-3.7 +/- 2.0 to 0.7 +/- 1.9; p = 0.01) and thickening (-5.0 +/- 2.8 to 2.4 +/- 3.8; p < 0.001), and was not significantly different than aortomyoplasty. These data show that aortomyoplasty has beneficial effects on ischemic left ventricular contractility, and may therefore be useful for treating inoperable coronary artery disease.