Evaluation of dilated cardiomyopathy by pulsed Doppler echocardiography

The ability of pulsed Doppler echocardiography to identify patients with left ventricular systolic dysfunction was evaluated in 12 patients with dilated (congestive) cardiomyopathy. A range-gated, spectrum analyzer-based Doppler velocimeter was used to record blood flow velocity in the ascending aorta and main pulmonary artery. The following blood flow velocity parameters were measured or derived: peak flow velocity, acceleration time, average acceleration, deceleration time, average deceleration, ejection time, and aortic flow velocity integral. Doppler blood flow velocity data in the cardiomyopathy patients were compared to data from 20 normal subjects. Measurements from the ascending aorta revealed that peak aortic flow velocity discriminated between cardiomyopathy patients (mean 47 cm/sec, range 35 to 62) and normal subjects (mean 92 cm/sec, range 72 to 120) with no overlap in data (p < 0.001). Aortic flow velocity integral was also able to separate the patients with dilated cardiomyopathy (mean 6.7 cm, range 3.5 to 9.1) from normal subjects (mean 15.7 cm, range 12.6 to 22.5) with no overlap in data (p < 0.001). Although mean values for average aortic acceleration and aortic ejection time were also significantly different (both p < 0.005), there was some overlap between the two groups. Pulmonary artery blood flow studies demonstrated significantly increased average acceleration, as well as decreased ejection time (both p < 0.05), but no difference in average deceleration or peak flow velocity in cardiomyopathy patients compared to normals. Compared to pulmonary flow measurements, aortic Doppler flow velocity measurements allowed better separation of cardiomyopathy and normal groups. In addition, aortic peak flow velocity appeared to correlate well (r = 0.83) with M-mode echocardiographic measurement of left ventricular percent fractional shortening; both parameters were equally useful in discriminating patients with normal left ventricular function from those with global dysfunction (dilated cardiomyopathy). Thus pulsed Doppler echocardiography appears to be a useful addition to M-mode and two-dimensional echocardiography in the quantitative noninvasive assessment of left ventricular systolic function. © 1983