Defining Advanced Heart Failure: A Systematic Review of Criteria Used in Clinical Trials

Background Enrollment criteria used in advanced heart failure (HF) clinical trials might identify a common set of widely accepted quantitative characteristics as the basis of a consensus definition for advanced HF, which is currently lacking. Methods We reviewed all clinical trials investigating interventions in patients with advanced HF as of July 31, 2015. Eligible publications (N = 134) reported original data from clinical trials explicitly defining advanced HF in adults. Results New York Heart Association (NYHA) class was the most common criterion (119 trials, 88.8%; classes ranged from II to IV), followed by left ventricular ejection fraction (LVEF) (84 trials, 62.7%; cutoff range, 20% to 45%; mode 35%). Other criteria included inotrope-dependent status (12.7%), peak oxygen consumption (10.4%), ≥1 previous HF admissions (10.4%), cardiac index (10.4%), pulmonary capillary wedge pressure (9.0%), left ventricular end-diastolic diameter (6.0%), and transplant listing status (5.2%). Cutoff points for quantitative criteria varied considerably. Previous HF admission was more frequently required in recent trials (P = .007 for temporal trend), whereas use of hemodynamic criteria decreased over time (P = .050 for temporal trend). Average LVEF among participants increased over time. Conclusions There is considerable variation in the definition of advanced HF for clinical trial purposes. Beyond NYHA and LVEF, a wide array of criteria has been used, with little consistency both in criteria selection and quantitative cutoff points.