In this episode of JACC Deep Dive, KACC Editor-in-Chief Harlan M. Krumholz, MD, SM, FACC, explores a post hoc analysis of the HELIOS-B trial, which examined whether echocardiographic parameters can track treatment response in transthyretin amyloid cardiomyopathy (ATTR-CM) patients treated with vutrisiran. The study found that changes in cardiac function correlated with clinical outcomes, suggesting a role for serial imaging in personalized care. Behind the scenes, reviewers were particularly intrigued by the potential of echocardiographic markers—especially global longitudinal strain—as surrogate endpoints, while also noting the exploratory nature of the findings and the need for further validation.