Allograft Pathology in Patients Transplanted for Idiopathic Dilated Cardiomyopathy.
Thomas Huebner, Jonathon Heath, Fabio Tavora, Bartley Griffith, Allen Burke. University of Maryland, Baltimore; Federal University of Sao Paulo, Brazil
Background: There are few morphologic studies of idiopathic dilated cardiomyopathy (CM) treated with transplant.
Design: We prospectively correlated gross, histologic and clinical findings of hearts explanted in a 5-year period from patients with a clinical diagnosis of non-ischemic CM, and correlated left ventricular diameter with preoperative echocardiographic reports.
Results: Of 103 consecutive allografts, the clinical diagnosis was ischemic heart disease (n=28), hypertrophic cardiomyopathy (n=4), failed allograft (n=4), amyloidosis (n=3), heart tumor (n=1), restrictive CM (n=1), and non-ischemic CM (62). In the last group, there were 41 men (51 ± 13 years) and 21 women (42 ± 18 years). The pathologic diagnosis was idiopathic (dilated) cardiomyopathy (DC) in 54 (87%), and specific cardiomyopathy in 8 (13%). Specific diagnoses were arrhythmogenic right ventricular cardiomyopathy (n=5), amyloid (n=2) and sarcoid (n=1), none of which were suspected clinically. The 54 hearts with idiopathic DC had a mean heart weight of 503 gms, (range 220-980 gms). Pathologic subsets of the DC group included 4 hearts without enlargement, cavity dilatation or significant histologic findings (minimal DC); 3 hearts with histologic evidence of healed myocarditis; and 5 hearts with features of left ventricular noncompaction. Four patients had prior mitral valve replacement to manage heart failure. There were 7 post-partum DC, 1 with a histologic pattern of healed myocarditis, and one alcoholism-associated DC. Familial DC comprised 16% (9 of 54 patients). In patients without prior assist device placement, pathologic left ventricular cavity diameter correlated with echocardiographic end-diastolic diameter (r2 0.8, p<.0001), but there was a mean 1.7 cm underestimation pathologically.
Conclusions: Non-ischemic cardiomyopathy is heterogeneous morphologically, and unexpected diagnoses are uncovered in over 10% of cases. Left ventricular measurement at explant correlates well with echocardiographic findings, with a relatively consistent underestimation of the diameter.
Wednesday, March 2, 2011 1:00 PM
Poster Session VI # 44, Wednesday Afternoon