Findings from a new Cleveland Clinic-led study show that patients with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) – a condition in which the heart muscle thickens and impedes the heart’s ability to pump blood – have a significantly improved overall quality of life after undergoing a type of open-heart surgery called septal myectomy.
Findings from the “SPIRIT-HCM Study: Quality of Life after Septal Myectomy in Obstructive Patients with Hypertrophic Cardiomyopathy” were reported today during a featured science session at the American Heart Association’s virtual Scientific Sessions 2021. This is the first prospective report in which patients with obstructive hypertrophic cardiomyopathy reported improved quality of life following surgery.
Hypertrophic cardiomyopathy is typically an inherited disease that affects an estimated 600,000 to 1.5 million Americans, or one in 500 people. People with the condition may develop heart ailments that shorten life or decrease the person’s quality of life, including sudden cardiac arrest or sudden cardiac death, and heart failure. Symptoms can include chest pain, shortness of breath and fatigue, syncope (fainting or passing out) and heart palpitations.
Treatment for hypertrophic cardiomyopathy typically includes lifestyle changes, medications and surgery. During a septal myectomy – the procedure performed in this study – the surgeon removes a small amount of the thickened septal wall to widen the outflow tract from the left ventricle to the aorta. Myectomy is considered when medications are not effective in treating hypertrophic cardiomyopathy. This frequently eliminates the mitral valve leakage.
The Kansas City Cardiomyopathy Questionnaire (KCCQ) is a widely used quality-of-life questionnaire originally designed and validated in the heart-failure population and recently employed as an endpoint in a clinical trial of patients with obstructive hypertrophic cardiomyopathy.
For the SPIRIT-HCM trial, in 136 patients who underwent surgical myectomy and completed follow-up, 125 (92%) achieved the primary endpoint (≥5 point improvement in KCCQ summary score) with 109 (80%) showing a large (>20 point) improvement. Also, 117 (86%) patients reported good to excellent health status (KCCQ summary score ≥75) at follow-up. In addition to KCCQ, there was a marked improvement in all other quality-of-life metrics, including PROMIS, DASI and EQ-5D scores, with a significant improvement observed in more than 80% patients.
“The primary goal of septal myectomy is to alleviate the symptoms and improve the quality of life in obstructive hypertrophic cardiomyopathy patients when medication is no longer effective,” said Milind Desai, M.D., MBA, director, Hypertrophic Cardiomyopathy Center and clinical operations in Cleveland Clinic’s Heart Vascular & Thoracic Institute, and principal investigator of the study. “However, its impact on quality of life, physical and social health has not been prospectively studied until now.
Steven Nissen, M.D., Chief Academic Officer of the Heart, Vascular and Thoracic Institute at Cleveland Clinic, said, “These findings demonstrate that septal myectomy in patients with symptomatic obstructive hypertrophic cardiomyopathy significantly improves overall quality of life, physical and social health status, left ventricular outflow tract obstruction, and functional capacity.”
This prospective study was investigator-initiated and entirely funded by philanthropic research support to Cleveland Clinic. Drs. Desai and Nissen serve on the Executive Steering Committee of “A Study to Evaluate Mavacamten in Adults With Symptomatic Obstructive HCM Who Are Eligible for Septal Reduction Therapy,” (VALOR-HCM) sponsored by Bristol Myers Squibb.
Dr. Desai is a consultant for Bristol Myers Squibb, Medtronic, Inc and Caristo Diagnostics.
Dr. Nissen has served as a consultant for many pharmaceutical companies and has overseen clinical trials for Amgen, AstraZeneca, Cerenis, Eli Lilly, Novartis, Novo Nordisk, The Medicines Company, Orexigen, Takeda and Pfizer. However, he does not accept honoraria, consulting fees or other compensation from commercial entities.