Differentiation of constrictive pericarditis and restrictive cardiomyopathy by radionuclide ventriculography

Patterns of left ventricular diastolic filling in five patients with unoperated constrictive pericarditis, the same five patients following pericardiectomy, five patients with restrictive cardiomyopathy, and 14 healthy control subjects were studied by radionuclide ventriculography. Patients with constrictive pericarditis had more rapid peak left ventricular filling rates (mean 5.62, range 4.23 to 7.32 end-diastolic volumes [EDV] per second) compared to control subjects 3.44, range 2.62 to 4.45 EDV/sec, p less than 0.05). Heart rate-corrected first one-third and first one-half diastolic filling fractions were greater in patients with preoperative constrictive pericarditis compared to members of the restrictive cardiomyopathy and control groups p less than 0.05). Following pericardiectomy, patients with constrictive pericarditis had significant decreases in peak filling rate and corrected filling fractions, and all diastolic filling measurements were indistinguishable from those of control subjects. These noninvasively obtained data indicate that patients with preoperative constrictive pericarditis have an increased rate of left ventricular early diastolic filling compared to patients with restrictive cardiomyopathy and control subjects, and that these findings return to normal following surgical removal of the pericardium.