Generalizability of Trial Data to Real-World Practice: An Analysis of The Society of Thoracic Surgeons Intermacs Database

Abstract

BackgroundAlthough the current wide-scale adoption of the HeartMate 3 left ventricular assist device can be attributed to favorable clinical trial outcomes, restrictive clinical trial eligibility criteria may result in lack of generalizability to real-world populations. We assessed the generalizability of left ventricular assist device clinical trial outcomes and evaluated the prognostic value of specific inclusion and exclusion criteria. MethodsThe Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Therapy With HeartMate 3 (MOMENTUM 3) eligibility criteria were applied to patients identified in The Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) who underwent HeartMate 3 implantation (n = 4610) between August 2017 and March 2020. Patients were categorized as trial-eligible or trial-ineligible and by number of ineligibility criteria. The effect of trial eligibility on mortality was estimated using Cox models. ResultsIndications for HeartMate 3 implant included destination therapy (n = 2827, 61%), bridge to candidacy (n = 969, 21%), and bridge to transplant (n = 702, 15%). A total of 1941 recipients (42%) were trial-ineligible, with 1245 (27%) meeting one ineligibility criterion, 470 (10%) meeting two, and 226 (5%) meeting three or more. Estimated 1-year mortality for trial-ineligible recipients was higher than for trial-eligible recipients (17% ± 1% vs 10% ± 1%, P < .001). Compared with trial-eligible patients, 1-year mortality was incrementally higher for patients meeting one ineligibility criterion (15% ± 1%), two criteria (16% ± 2%), and three or more criteria (30% ± 3%). Thrombocytopenia and elevated creatinine, bilirubin, and international normalized ratio in trial-ineligible patients were independently associated with increased mortality. ConclusionsDespite differences in mortality, both trial-eligible and trial-ineligible HeartMate 3 recipients had excellent outcomes in real-world practice, suggesting future trial eligibility criteria could be expanded.