Platelet survival in patients with dilated cardiomyopathy.
Dilated cardiomyopathy is associated with thromboembolic complications, which correlate poorly, however, with a visible left ventricular thrombus. Therefore, this study was performed to assess whether an abnormality of platelet function in vivo can be detected in patients with dilated cardiomyopathy. Platelet survival was measured after autologous labeling with indium-111 oxine in 28 patients with dilated cardiomyopathy and angiographically normal coronary arteries (mean ejection fraction 21 +/- 9% [standard deviation], range 4 to 39%) and in nine patients with coronary artery disease and similar left ventricular dysfunction (mean ejection fraction 21 +/- 10%). Plasma levels of beta-thromboglobulin and platelet factor 4 were measured in patients with idiopathic cardiomyopathy (n = 15) and platelet scintigraphic images of the heart (n = 24) were obtained in subsets of both patient groups. Platelet survival was significantly and similarly shortened in patients with idiopathic and ischemic cardiomyopathy (67 +/- 34 and 55 +/- 24 h, respectively) compared to controls (209 +/- 9 h, n = 12; p less than 0.001). Of the two platelet-specific proteins, beta-thromboglobulin was increased in the patients compared with controls (42 +/- 17 versus 22 +/- 6 ng/ml, p less than 0.001). Platelet scintigraphy 24 h (n = 24) and/or 48 h (n = 9) after labeling showed a diffuse pattern of enhanced platelet uptake over the heart which varied in intensity among patients, but which was never seen in controls (n = 6). This increased platelet uptake was similar in patients with idiopathic and ischemic cardiomyopathy but did not correlate with either ejection fraction or cardiothoracic ratio.(ABSTRACT TRUNCATED AT 250 WORDS)
Weidinger
F
F
Department of Cardiology, University of Vienna, Austria.
Glogar
D
D
Sochor
H
H
Sinzinger
H
H
D000328:Adult; D001792:Blood Platelets / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D002311:Cardiomyopathy, Dilated / Q000097:blood* / Q000000981:diagnostic imaging; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D007205:Indium Radioisotopes; D008297:Male; D008875:Middle Aged; D010978:Platelet Factor 4 / Q000378:metabolism; D011877:Radionuclide Imaging; D014859:Warfarin / Q000494:pharmacology; D001620:beta-Thromboglobulin / Q000378:metabolism
D007205:Indium Radioisotopes; D001620:beta-Thromboglobulin; D010978:Platelet Factor 4; D014859:Warfarin