Assessment of anthracycline-induced long-term cardiotoxicity in patients with hematological malignancies

Approach to Lymphoma-Associated Cardiomyopathy

Cardiomyopathy is a disease of the myocardium that affects the heart structure and function, eventually resulting in heart failure, valvular regurgitation, arrhythmia, or even sudden cardiac death. Occurring following treatment of lymphoma, both Hodgkin's and Non-Hodgkin's, cardiomyopathy is a feared complication in these cancer survivors due to its significant association with morbidity and mortality. A review of the literature was conducted using a combination of keywords including "Cardiomyopathy," "Anthracycline," "Radiation," "Pathogenesis," and "Management." Anthracyclines and radiation are prominent entities explored in the discussion of lymphoma-associated cardiomyopathy, whereby the formation of reactive oxygen species following treatment with both has been seen in the pathogenesis. The current standard of care thus far for anthracycline-induced cardiomyopathy includes heart failure medications such as beta-blockers, angiotensin-converting enzyme inhibitors, aldosterone receptor antagonists, and loop-diuretics. On the other hand, radiation-induced cardiomyopathy management has not been well-established yet in literature, with agents such as antioxidants and anti-inflammatory drugs still being studied in rat models. The treatment approach to cardiotoxicity in a lymphoma patient should consist of a collaboration between the oncologist and cardiologist prior to lymphoma treatment initiation, to stratify the risk of development of cardiomyopathy in the patient, and decide the best chemotherapy or radiotherapy agent, dosing, and surveillance technique.

Electrocardiographic and biochemical analysis of anthracycline induced cardiotoxicity in breast cancer patients from Southern Sri Lanka

BACKGROUND

The clinical application of anthracycline chemotherapy is hindered due to the cumulative dose-dependent cardiotoxicity followed by the oxidative stress initiated during the mechanism of action of anthracyclines. Due to a lack of prevalence data regarding anthracycline-induced cardiotoxicity in Sri Lanka, this study was conducted to determine the prevalence of cardiotoxicity among breast cancer patients in Southern Sri Lanka in terms of electrocardiographic and cardiac biomarker investigations.

METHODS

A cross-sectional study with longitudinal follow-up was conducted among 196 cancer patients at the Teaching Hospital, Karapitiya, Sri Lanka to determine the incidence of acute and early-onset chronic cardiotoxicity. Data on electrocardiography and cardiac biomarkers were collected from each patient, one day before anthracycline (doxorubicin and epirubicin) chemotherapy, one day after the first dose, one day and six months after the last dose of anthracycline chemotherapy.

RESULTS

Prevalence of sub-clinical anthracycline-induced cardiotoxicity six months after the completion of anthracycline chemotherapy was significantly higher (p < 0.05) and there were strong, significant (p < 0.05) associations among echocardiography, electrocardiography measurements and cardiac biomarkers including troponin I and N-terminal pro-brain natriuretic peptides. The cumulative anthracycline dose, > 350 mg/m² was the most significant risk factor associated with the sub-clinical cardiotoxicity in breast cancer patients under study.

CONCLUSION

Since these results confirmed the unavoidable cardiotoxic changes following anthracycline chemotherapy, it is recommended to carry out long-term follow-ups in all patients who were treated with anthracycline therapy to increase their quality of life as cancer survivors.

Assessment and Management of Cardiotoxicity in Hematologic Malignancies

With the increasing overall survival of cancer patients due to recent discoveries in oncology, the incidence of side effects is also rising, and along with secondary malignancies, cardiotoxicity is one of the most concerning side effects, affecting the quality of life of cancer survivors. There are two types of cardiotoxicity associated with chemotherapy; the first one is acute, life-threatening but, fortunately, in most of the cases, reversible; and the second one is with late onset and mostly irreversible. The most studied drugs associated with cardiotoxicity are anthracyclines, but many new agents have demonstrated unexpected cardiotoxic effect, including those currently used in multiple myeloma treatment (proteasome inhibitors and immunomodulatory agents), tyrosine kinase inhibitors used in the treatment of chronic myeloid leukemia and some forms of acute leukemia, and immune checkpoint inhibitors recently introduced in treatment of refractory lymphoma patients. To prevent irreversible myocardial damage, early recognition of cardiac toxicity is mandatory. Traditional methods like echocardiography and magnetic resonance imaging are capable of detecting structural and functional changings, but unable to detect early myocardial damage; therefore, more sensible biomarkers like troponins and natriuretic peptides have to be introduced into the current practice. Baseline assessment of patients allows the identification of those with high risk for cardiotoxicity, while monitoring during and after treatment is important for early detection of cardiotoxicity and prompt intervention.