Peak aortic blood acceleration: a possible indicator of initial left ventricular impairment in patients with coronary...

In 25 patients undergoing diagnostic cardiac catheterization, a catheter-tip electromagnetic velocity transducer was used to evaluate maximum velocity and acceleration of blood in the ascending aorta. All patients underwent a complete haemodynamic evaluation, including high-fidelity recording of intraventricular pressures and calculation of the derived indices, left ventriculography and coronary angiography. Nineteen patients with critical coronary stenoses were divided according to the presence of signs of left ventricular dysfunction, while the control group consisted of six subjects with chest pain, but without cardiac abnormalities detectable by cardiac catheterization. Maximum aortic acceleration was significantly lower in coronary patients (378 +/- 130 vs 562 +/- 82 in the control group P less than 0.01) and also in the selected subgroup of coronary patients with normal haemodynamic and angiographic indices of left ventricular systolic function (310 +/- 102 vs 562 +/- 82, P less than 0.01). No relationship could be observed between maximal blood acceleration and left ventricular peak systolic pressure, +dP/dt, left ventricular end-systolic volume index and ejection fraction. Our results suggest that maximal blood acceleration from the left ventricle may detect an initial myocardial impairment in patients with definite coronary artery disease but with normal conventional indices of left ventricular function. The clinical interest of this index, however, is limited by overlapping values in patients with and without coronary artery disease and the inability of a further separation of ischaemic patients in accordance with the severity of left ventricular impairment and the extension of coronary artery involvement.