Pathology in patients with ventricular assist devices: a study of 21 autopsies, 24 ventricular apical core biopsies and 24 explanted hearts.
BACKGROUND
Ventricular assist devices (VADs) are used as a bridge to cardiac transplantation or as a permanent or sometimes temporary treatment for end stage heart failure.


METHODS
Our autopsy and surgical pathology experience with VADs prior to August 2002 was reviewed. Noted were patient's age, sex, underlying (UCOD) and proximate causes of death (PCOD), duration of VAD implantation, presence of native or prosthetic valvar disease and organ complications. Myocardium from biopsies and explanted hearts were blindly assessed for coagulative necrosis (CN), contraction bands (CB), myocytolysis (MC), increased eosinophilia (IE), myocyte waviness (MW) and fibrosis (F). Each was graded as either mild (score 1), moderate (score 2) or severe (score 3).


RESULTS
Autopsy patients: Twenty-one patients, with mean age 55 years (range 10-73), comprised 10 women and 11 men. UCOD was ischemic disease in 16 patients, dilated cardiomyopathy in 4 and aortic valve disease in 1. The mean duration of VAD implantation was 125.7 days (range 1-1095 days, S.D.=253.6). Five patients had biventricular VADs, and 16 had LVAD only. Acquired aortic valve fusion was noted in three patients. PCOD was VAD related in six, donor heart problem in four, cerebrovascular accident in four, miscellaneous in three, pulmonary hypertension in two and aortic disease in two patients. Morbidity: local liver necrosis in seven, acquired aortic valve disease in four, gut infarction in three, abdominal aortic aneurysm in two and host cell assault against VAD porcine aortic valves in one case. Biopsies and explanted hearts: Twenty-four patients had a mean age of 53 years (range 38-68, S.D.=8.6). VADs were implanted for 177.8 days (range 7-593 days, S.D.=151.1). Comparison of histologic scores of biopsies with explanted hearts showed the following: CN 1.33 (S.D.=1.4)/0.21 (S.D.=0.66; P<.001); CB: 2.1 (S.D.=0.93)/0.83 (S.D.=0.28; NS); MC: 0.88 (S.D.=1.19)/0.13 (S.D.=0.34; P<.01); IE: 1.71 (S.D.=1.27)/0.38 (S.D.=0.65; NS); fibrosis: 1.08 (S.D.=1.35)/1.75 (S.D.=1.26; NS); and MW: 1.50 (S.D.=1.22)/0.59 (S.D.=0.73; P<.01). Acquired aortic stenosis developed in six hearts, and one heart showed thrombotic occlusion of the left ventricular outflow tract below an aortic bioprosthesis.


CONCLUSIONS
VAD significantly reduced the amount of CN, MC and MW in the left ventricle but may lead to acquired aortic stenosis of native aortic valves or total occlusive thrombosis of aortic prosthetic valves. Proximate cause of death was, most often, VAD related.
Rose
Alan G
AG
Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Room C-445, Mayo Building, 420 Delaware Street, SE, Minneapolis, MN 55455, United States. rosex031@umn.edu
Park
Soon J
SJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D001021:Aortic Valve / Q000473:pathology; D001024:Aortic Valve Stenosis / Q000209:etiology / Q000473:pathology; D001706:Biopsy; D002648:Child; D005260:Female; D016027:Heart Transplantation / Q000009:adverse effects* / Q000379:methods / Q000401:mortality; D006352:Heart Ventricles / Q000473:pathology* / Q000601:surgery; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D032342:Muscle Cells / Q000473:pathology*; D009206:Myocardium / Q000473:pathology*; D011183:Postoperative Complications / Q000401:mortality / Q000473:pathology*; D015996:Survival Rate