DISCREPANCIES IN THE DOPPLER ECHOCARDIOGRAPHIC AND RADIONUCLIDE ANGIOGRAPHIC ASSESSMENT OF LEFT-VENTRICULAR FILLING IN IDIOPATHIC DILATED CARDIOMYOPATHY

Doppler echocardiography and radionuclide angiography were shown to provide valuable tools with comparable functional parameters for the noninvasive assessment of left ventricular (LV) diastolic function in patients with coronary artery disease or LV hypertrophy. In order to examine the influence of an impaired systolic function on both methods, we studied LV filling simultaneously by Doppler echocardiography and radionuclide angiography in 47 patients with idiopathic dilated cardiomyopathy and stable sinus rhythm. The Doppler echocardiographic peak velocities (V(E), V(A)) and radionuclide angiographic peak filling rates (PFR(FF), PFR(A)) normalized to either left ventricular enddiastolic volume or stroke volume were measured and systolic function was assessed by obtaining the ejection fraction (EF) with the radionuclide angiography. Patients were divided into two groups with moderately (group 1: EF greater-than-or-equal-to 35 %) or severely impaired (group 2: EF < 35 %) systolic function. In group 2 the PFR(FF) (1.8 +/- 0.5 vs. 3.3 +/- 0.8 SV/s; p < 0.01) and PFR(A) (1.2 +/- 0.6 vs. 2.5 +/- 1.0 SV/s; p < 0.01) were both lower than in group 1, as was the Doppler echocardiographic V(A) (0.44 +/- 0.20 vs. 0.63 +/- 0.17 m/s; p < 0.01). However, V(E) was increased with reduced systolic function (0.75 +/- 0.20 vs. 0.53 +/- 0.16 m/s; p < 0.01). No relation was found between PFR(FF) and V(E) and only a weak relation between the atrial filling parameters of Doppler echocardiography and radionuclide angiography. The peak filling rates were closely correlated with the systolic function (PFR(FF): r = 0.86; p < 0.001) and were reduced with an impaired systolic function. V(A) was also reduced with the reduction of the EF (r = 0.45; p < 0.001) but V(E) was increased (r = -0.56; p < 0.001). Unlike in patients with normal systolic function, the Doppler echocardiographic and radionuclide angiographic parameters for the noninvasive assessment of LV diastolic filling yield differential results in patients with dilated cardiomyopathy due to the differential influence of the impaired systolic function.