Monitoring of cardiac function on the basis of serum troponin I levels in patients with acute leukemia treated with anthracyclines

Anthracyclines are used extensively in the therapy of hematologic malignancies. However, their use has been limited by acute and chronic cardiotoxicity. Cardiac troponins have emerged as sensitive and specific markers of even minor myocardial damage. In this study we prospectively evaluated serial measurements of serum cardiac markers and echocardiography in patients with de novo acute myeloid and lymphoid leukemias (AML and ALL, respectively) treated with anthracyclines. We examined and subdivided 79 patients into 3 groups: group 1 (37 patients with AML, all <60 years), group 2 (25 with AML, all ≥60 years), group 3 (17 with ALL). Serum specimens were collected before treatment and during and after therapy and were analyzed for troponin I (TnI), myoglobin, creatine phosphokinase-muscle myocardium isoenzyme B, and lactate dehydrogenase concentrations. In group 1, 4 of the 37 patients (11%) had increased levels of TnI on the 14th day of induction therapy, but by the 28th day the TnI level had returned to normal in 3 of these 4 patients. In group 2, 3 of the 25 patients (12%) demonstrated increased TnI concentrations on the 7th day of induction therapy, but by the 14th day these levels had normalized in 2 of the 3. In group 3, we detected no increased TnI concentrations. Echographic study did show a significant correlation with the TnI levels (P<.001), involving a reversible decrease in left ventricular ejection fraction among patients with increased TnI levels (>0.15 ng/mL) on day 14 in group 1 and on day 7 in group 2. These results may aid the clinician in the treatment of patients by identifying high-risk patients who may benefit from closer observation or supportive cardiac therapy.