Utility Of Pre-Chemotherapy Echocardiograms

Anthracycline-based chemotherapy is widely used in a variety of regimens for Hodgkin’s Lymphoma (HL) and Non-Hodgkin’s Lymphoma (NHL). Unfortunately this agent is associated with cardiotoxicity, especially in larger cumulative doses. Doxorubicin cardiotoxicity is characterized by a dose-dependent decline in mitochondrial oxidative phosphorylation. Reactive oxygen species, generated by the interaction of doxorubicin with iron, can then damage the myocytes causing myofibrillar loss, cytoplasmic vacuolization, and apoptosis.

Current NCCN guidelines for HL and NHL state that left ventricle function is recommended in patients who will receive such chemotherapy. Subsequent evaluations are recommended at a cumulative dose of doxorubicin of at least 300 mg/m² and periodically thereafter during the course of therapy. Despite these recommendations, there is little literature about the usefulness of this approach, the rate of abnormal findings, and whether routine testing changes management.

A list of patients with HL or NHL treated with anthracycline-based chemotherapy from the University of Nebraska Medical Center from August 2004-May 2012 was obtained from our Lymphoma Registry.

Baseline characteristics of age, disease diagnosis, gender, and prior history of cardiac diagnosis were collected. Prior cardiac diagnosis specified as patients with a past history of atrial fibrillation/flutter, supraventricular tachycardia, heart block requiring pacemaker implantation, coronary artery disease, valvular disease, pulmonary hypertension, or cardiomyopathy.

Charts were reviewed for pre-chemotherapy evaluation of left ventricular function and the method of evaluation (echocardiogram, nuclear, cardiac MRI were included). Additionally, post treatment evaluation of cardiac function was evaluated for any change.

The individual therapy for each patient was reviewed to determine if findings from the cardiac evaluation modified treatment regimens.

A left ventricular function less than 50% was considered abnormal. Echocardiogram findings of moderate to severe valvular disease, diastolic dysfunction (grade 1-3), and moderate or severe pulmonary hypertension (moderate = pulmonary artery systolic pressure of 45-60, severe = pulmonary artery systolic pressure of > 60) were collected.

We identified 309 patients from the UNMC lymphoma database. Of these 219 (71%) had an echocardiogram performed prior to therapy and documented in the patient record. Their mean age was 54.2 years of age with 53% of them being male and 47% female.

188 of the 219 (86%) had no prior cardiac diagnosis as defined previously. From this group 22 of the 188 (10%) had a pre-chemotherapy echocardiogram that demonstrated one of the following: moderate-severe valvular disease, diastolic dysfunction, moderate-severe pulmonary hypertension or abnormal EF (<50%). However, none of these findings altered the chemotherapy regimen for the 22 patients.

31 of the 219 patients with echocardiograms carried a prior cardiac diagnosis. 4 of the 31 had an alteration in their chemotherapy regimen as a result. Post therapy echocardiograms showed no change in cardiac function.

5 of the 219 patients were diagnosed with adriamycin induced cardiomyopathy following treatment. All 5 patients had no prior cardiac history and pre-chemotherapy echocardiograms were normal.

These finding suggest that current methods of evaluating cardiac function prior to chemotherapy and risk stratifying patients are inadequate and do not alter patient outcomes.