La determinazione della troponina T con il metodo ad alta sensibilità migliora la sensibilità di rilevazione della cardiomiopatia nell'amiloidosi AL

In AL amyloidosis cardiac involvement dictates prognosis. It has been demonstrated that cardiac dysfunction is best assessed by measuring serum concentrations of N-terminal B-type natriuretic peptide (NT-proBNP) and cardiac troponins. Recently, a new generation of more sensitive assays for troponin measurement has been developed, aiming at identifying minimal cardiac damage. We report the impact of the introduction of a highly sensitive cardiac troponin T (hs-cTnT) assay (Roche Diagnostics) on the detection of cardiac involvement in 109 consecutive newly diagnosed patients with AL amyloidosis. The hs-cTnT was determined on the Modular E system. Cardiac troponin I (cTnI) (Siemens TnI-Ultra™) and NT-proBNP (Roche Diagnostics) were also measured. Sixty nine (63%) patients had cardiac involvement at presentation, as detected by echocardiography. The diagnostic sensitivity of the biomarkers to detect cardiac involvement at diagnosis was 74% for cTnI, 96% for hs-cTnT, and 100% for NT-proBNP, respectively. In additional 15 patients, echographic evidence of amyloid heart involvement developed during 6 months following diagnosis: cTnI was elevated at presentation in 5 cases (33%), hs-cTnT in 12 (80%, P=0,01 versus cTnI) and NT-proBNP in 11 cases (73%). We conclude that hs-cTnT may improve the sensitivity for detection of cardiac damage caused by AL amyloidosis.