A recent study conducted by the Mayo Clinic has cast doubt on the effectiveness of implantable cardioverter-defibrillators (ICDs) in improving longevity for patients diagnosed with transthyretin cardiac amyloidosis (ATTR-CM), a progressive and often fatal heart condition.
The research, detailed in reports from February 2026, challenges long-held assumptions about the benefits of ICDs in this patient population. Traditionally, ICDs have been used to prevent sudden cardiac death by delivering an electrical shock to restore a normal heart rhythm. Although, the Mayo Clinic study suggests that this intervention may not translate into extended lifespans for individuals with ATTR-CM.
Cardiac amyloidosis occurs when abnormal proteins, specifically amyloid fibrils, deposit in the heart, causing the organ to stiffen and impair its ability to function properly. ATTR-CM is a subtype of this condition caused by the misfolding of the transthyretin protein. The condition is believed to affect between 50,000 and 150,000 Americans, according to recent reports.
The findings come as the therapeutic landscape for cardiac amyloidosis is rapidly evolving. Advances in diagnosis and treatment are offering new hope to patients, with the potential to transform the condition from a terminal diagnosis to a manageable chronic illness, according to a report published in the Journal of the American College of Cardiology. New therapies are focused on stabilizing the transthyretin protein and preventing further amyloid deposition.
The MedStar Heart & Vascular Institute is among the institutions offering these advanced treatments, aiming to improve both the quality of life and longevity for patients with ATTR-CM. These therapies represent a shift in approach, moving beyond symptom management to address the underlying cause of the disease. However, the role of ICDs in this new paradigm remains unclear following the Mayo Clinic’s recent findings.
Researchers at the Scuola Superiore Sant’Anna in Pisa, Italy, have been actively involved in innovations in the diagnosis and treatment of cardiac amyloidosis, but have not yet commented on the implications of the Mayo Clinic study. Further research is needed to determine the optimal treatment strategies for patients with ATTR-CM, and whether ICDs should continue to be a standard component of care.
