Log in to MyACC
CRT and LVEF Change in Chemotherapy-Induced Cardiomyopathy
Study Questions:
What is the association of cardiac resynchronization therapy (CRT) with improvement in cardiac function, as well as clinical improvement in patients with chemotherapy-induced cardiomyopathy (CHIC)?
Methods:
MADIT-CHIC (Multicenter Automatic Defibrillator Implantation Trial–Chemotherapy-Induced Cardiomyopathy) was an uncontrolled, prospective cohort study conducted between November 21, 2014, and June 21, 2018, at 12 tertiary centers with cardio-oncology programs in the United States. Thirty patients were implanted with CRT owing to left ventricular ejection fraction (LVEF) ≤35%, New York Heart Association class II-IV heart failure (HF) symptoms, and wide QRS complex with established CHIC. They were followed up for 6 months after CRT implantation. The primary endpoint was change in LVEF from baseline to 6 months after initiating CRT. Secondary outcomes included all-cause mortality and change in LV end-systolic volume and end-diastolic volume. All statistical tests were 2-sided and a p < 0.05 was considered statistically significant.
Results:
Among 30 patients who were enrolled (mean [standard deviation] age, 64 [11] years; 26 women [87%], most patients had a history of breast cancer (73%), six patients (20%) had a history of lymphoma or leukemia, and two patients (7%) had a diagnosis of sarcoma. Of these patients, 24 (83%) received anthracycline therapy (mean equivalent cumulative doxorubicin dose, 307 mg/m2). Besides anthracyclines, three patients received cyclophosphamide, one received trastuzumab, one dasatinib, and one docetaxel. Primary endpoint data were available for 26 patients and secondary endpoint data were available for 23 patients. Patients had nonischemic cardiomyopathy with left bundle branch block (LBBB), median LVEF of 29%, and a mean QRS duration of 152 ms. Patients with CRT experienced a statistically significant improvement in mean LVEF at 6 months from 28% to 39% (difference, 10.6%; 95% confidence interval [CI], 8.0%-13.3%; p < 0.001). This was accompanied by a reduction in LV end-systolic volume from 122.7 to 89.0 ml (difference, 37.0 ml; 95% CI, 28.2-45.8) and reduction in LV end-diastolic volume from 171.0 to 143.2 ml (difference, 31.9 ml; 95% CI, 22.1-41.6; both p < 0.001). Adverse events included a procedure-related pneumothorax (one patient), a device pocket infection (one patient), and heart failure requiring hospitalization during follow-up (one patient).
Conclusions:
The authors concluded that in this preliminary study of patients with CHIC, CRT was associated with improvement in LVEF after 6 months. The findings are limited by the small sample size, short follow-up, and absence of a control group.
Perspective:
This pilot study demonstrates that CRT improves LV function in patients with LBBB and CHIC, and may have a role in improving outcomes. Selection of patients will require shared decision making with the patient, oncologist, and cardiologist.
Keywords: Anthracyclines, Arrhythmias, Cardiac, Breast Neoplasms, Bundle-Branch Block, Cardiac Resynchronization Therapy, Cardiomyopathies, Cardio-oncology, Cardiotoxicity, Defibrillators, Implantable, Doxorubicin, Heart Failure, Leukemia, Lymphoma, Pneumothorax, Sarcoma, Secondary Prevention
< Back to Listings
