Maria Teresa Sandri

BACKGROUND: An increase in troponin I soon after high-dose chemotherapy (HDC) is a strong predictor of poor cardiological outcome in cancer patients. This finding has important clinical implications and provides a rationale for the development of prophylactic strategies for preventing cardiotoxicity. Angiotensin-converting enzyme inhibitors slow the progression of left ventricular dysfunction in different clinical settings, but their role in the prevention of cardiotoxicity has never been investigated. METHODS AND RESULTS: Of the 473 cancer patients evaluated, 114 (72 women; mean age, 45+/-12 years) who showed a troponin I increase soon after HDC were randomized to receive (angiotensin-converting enzyme inhibitor group; 20 mg/d; n=56) or not to receive (control subjects; n=58) enalapril. Treatment was started 1 month after HDC and continued for 1 year. Cardiological evaluation was performed at baseline and at 1, 3, 6, and 12 months after HDC. The primary end point was an absolute decrease >10 percent units in left ventricular ejection fraction, with a decline below the normal limit value. A significant reduction in left ventricular ejection fraction and an increase in end-diastolic and end-systolic volumes were observed only in untreated patients. According to the Kaplan-Meier analysis, the incidence of the primary end point was significantly higher in control subjects than in the angiotensin-converting enzyme inhibitor group (43% versus 0%; P<0.001). CONCLUSIONS: In high-risk, HDC-treated patients, defined by an increased troponin I value, early treatment with enalapril seems to prevent the development of late cardiotoxicity.

BACKGROUND: In patients with aggressive malignancies who are undergoing high-dose chemotherapy, even minimal elevation of troponin I (TnI) is associated with late left ventricular dysfunction. The time course of the subclinical myocardial damage and its impact on the clinical outcome have never been investigated previously. METHODS AND RESULTS: In 703 cancer patients, we measured TnI soon after chemotherapy (early TnI) and 1 month later (late TnI). Troponin was considered positive for values > or =0.08 ng/mL. Clinical and left ventricular ejection fraction evaluation (echocardiography) were performed before chemotherapy, 1, 3, 6, and 12 months after the end of the treatment, and again every 6 months afterward. Three different TnI patterns were identified, and patients were grouped accordingly. In 495 patients, both early and late TnI values were <0.08 ng/mL (TnI-/- group); in 145, there was only an early increase (TnI+/- group); and in 63 patients, both values increased (TnI+/+ group). In the TnI-/- group, no significant reduction in ejection fraction was observed during the follow-up, and there was a very low incidence of cardiac events (1%). In contrast, a greater incidence of cardiac events occurred in TnI-positive patients, particularly in the TnI(+/+) group (84% versus 37% in the TnI+/- group; P<0.001). CONCLUSIONS: TnI release pattern after high-dose chemotherapy identifies patients at different risks of cardiac events in the 3 years thereafter. This stratification allows us to differentiate the monitoring program and to plan, in selected patients, preventive strategies aimed at improving clinical outcome.