Medline ® Abstract for Reference 32
of 'Acquired TTP: Clinical manifestations and diagnosis'
Cardiac involvement in acute thrombotic thrombocytopenic purpura: association with troponin T and IgG antibodies to ADAMTS 13.
Hughes C, McEwan JR, Longair I, Hughes S, Cohen H, Machin S, Scully M
J Thromb Haemost. 2009;7(4):529. Epub 2009 Jan 19.
INTRODUCTION: Evidence for cardiac involvement in thrombotic thrombocytopenic purpura (TTP) is uncommonly described.
METHODOLOGY: We retrospectively reviewed 41 patients assessing troponin T as a marker for cardiac involvement in acute TTP with clinical symptoms, electrocardiograms (ECG) and echocardiograms. A histopathological review of five patients who died of acute TTP was also undertaken.
RESULTS: In 54% (22/41) of patients, troponin T was>or=0.05microg L(-1) (normal range 0-0.01 microg L(-1)). Half (12/22) had cardiac symptoms and 8/22 with a raised troponin T reported chest pain. ECG changes were present in 62% of patients with a raised troponin T. Median anti-ADAMTS 13 IgG antibody was significantly higher (P=0.018) in patients with troponin T>or=0.05 microg L(-1) (58.5% (range 17-162%), compared with patients with troponin T<0.05 microg L(-1) (35%, range 9-134%). Patients who died had higher troponin T levels (median 0.305 microg L(-1)) and raised anti-ADAMTS 13 IgG (median 66.5%). On admission, there were no deaths in those with troponin T<or=0.04microg L(-1). Histology confirmed widespread myocardial microvascular thrombi.
CONCLUSION: Clinical symptoms, ECG changes and echocardiograms are poor predictors of cardiac disease in acute TTP. Troponin T is specific for cardiac muscle and a sensitive marker of myocardial damage. In TTP patients, raised levels (>or=0.05 microg L(-1)) signify myocardial necrosis associated with microvascular thrombi. Mortality and acute morbidity was associated with higher admission troponin T and raised IgG antibody (>67%) to ADAMTS 13.
Department of Haematology, University College London Hospitals, London, UK.