Heart Rhythm 2023: Strides Made Toward Balanced Sex, Racial Representation in Clinical Studies

Results from the BIO-LIBRA Study achieved balanced sex representation among enrolled patients in a device study. The ongoing study assesses outcomes of device-treated ventricular arrhythmias or mortality in patients with non-ischemic cardiomyopathy (NICM) being treated with implantable cardioverter-defibrillators (ICDs) or cardiac resynchronization therapy defibrillators (CRT-Ds) along with guideline-directed medical therapy (GDMT) for heart failure. The study findings were presented during Heart Rhythm 2023.
 
NICM refers to the heart muscle weakening that is not caused by coronary artery disease of the heart and, without treatment, can lead to life-threatening complications such as heart failure and life-threatening arrhythmias.¹ Heart disease is currently the leading cause of death among U.S. women. For patients with NICM, physicians often consider cardiac rhythm devices to help improve heart function, relieve symptoms, and treat life-threatening arrhythmias. While implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy devices (CRT-Ds) are common treatment options for heart failure patients, there is not a lot of recent data collected on the impact of ICDs on NICM patients and enrollment of women in device trials is historically low (<30%).²
 
The BIO-LIBRA study, a multi-center, prospective, observational study, enrolled 1,000 patients at 48 enrolling U.S. sites. Patients were implanted with BIOTRONIK ICDs or CRT-Ds with home monitoring to be uniformly assessed for the primary endpoint of device-treatment ventricular tachycardia (VT) or ventricular fibrillation (VF). Secondary endpoints included all-cause mortality, VT or VF, cardiac death and sudden cardiac death by sex and by device type.
 
To address the lack of diverse enrollment, the authors created the BIO-LIBRA model, which champions female recruitment at each site and includes a variety of tools like patient and coordinator talking points, tailored patient education materials and key consenting tips for women shared at investigator meetings and in newsletters at enrolling sites in the United States. The study successfully recruited 475 of 1,000 (47.5%) female patients, exceeding the enrollment goal of 40% women. Additionally, 30% of the enrolled subjects were non-white and 10% self-reported their ethnicity as Hispanic/Latino.
 
Preliminary findings from follow-up of all subjects showed women with NICM, especially those with a CRT-D, had a significantly lower rate of VT/VF/death events compared to men. The authors report that novel guideline-directed medical therapy with angiotensin receptor blocker/neprilysin inhibitors (ARNI) was high, 42%, and sodium-glucose cotransporter-2 (SGLT2) inhibitors increased over time, suggesting ongoing therapy optimization in patients with implanted medical devices.
 
“This BIO-LIBRA model will pave the path for future medical device studies, transforming the way women and minorities are enrolled in clinical studies,” said Dr. Valentina Kutyifa, M.D., Ph.D., University of Rochester Medical Center in Rochester, N.Y. “The study also sheds new light on the intricate, interconnected relationship between sex, race, and device type on patient outcomes and offers a more balanced picture of NICM patients. We hope these findings will help close this knowledge gap and shape future research and interventions that will improve health outcomes for all—no matter your race or sex.”
 
The authors assert that the results of the BIO-LIBRA study will inform future scientific consensus and guideline documents regarding the role of ICD therapy in both men and women with a nonischemic cause of heart failure. The authors also added that a long-term, three-year follow-up of the enrolled subjects is currently underway.
 
The Heart Rhythm Society (HRS) is a 501(c)(3) international nonprofit organization and leader in science, education, and advocacy for cardiac arrhythmia professionals and patients. HRS is the primary information resource on heart rhythm disorders and promotes research, education, and optimal healthcare policies and standards. Incorporated in 1979 and based in Washington, D.C., it has a membership of more than 8,000 heart rhythm professionals from 94 countries. 

References 
¹ Vijayapraveena PA, Simonette SI et al, Prognostic Value of Late Gadolinium Enhancement in Patients with Non-Ischemic Cardiomyopathy. AHA J Med. 2011;124:A10684
² Segan, Tamirisa et al, Gender Equity in the EP Field: Time to Ignite the Spark, 2022