Introduction: Challenging the Ejection Fraction Paradigm
For decades, cardiac amyloidosis (CA) was taught as the quintessential model of restrictive cardiomyopathy—a disease characterized by rigid ventricles, impaired filling, and a paradoxically preserved left ventricular ejection fraction (LVEF). However, as our diagnostic capabilities have evolved from post-mortem findings to sophisticated imaging and biochemical screening, this monolithic view has been challenged. Clinicians frequently encounter CA patients with varying degrees of systolic impairment or, conversely, those who maintain near-normal diastolic function in the early stages of the disease.
A recent landmark study by Zampieri et al., published in Circulation: Heart Failure, provides a rigorous re-evaluation of these phenotypes. By analyzing a massive real-world cohort of patients with both Transthyretin (TTR-CA) and Light Chain (AL-CA) amyloidosis, the researchers have clarified the prevalence of these states and, more importantly, their prognostic trajectories. Their findings suggest that while restriction is indeed the most common presentation, the transition between states is a dynamic process that clinicians must navigate with precision.
