Phenotype characterization of heart failure with preserved ejection fraction in medical device and surgical trials

Heart failure with preserved ejection fraction (HFpEF) prevalence is nearing 50% of all heart failure cases and is often associated with advanced age, obesity, atrial fibrillation and hypertension, and medical approaches are limited. This review aims to determine the potential of medical devices or surgical interventions in treating HFpEF and to propose specific phenotypes of HFpEF.

A systematic review was conducted using various clinical trial databases and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines followed by descriptive analysis and methodology quality assessment. Inclusion criteria included a medical device or surgical intervention involving HFpEF patients defined by a left ventricular ejection fraction (LVEF) ≥50% and signs of diastolic dysfunction. Twenty-four novel trials were identified involving n = 1752 participants: 17 medical device trials [3 interatrial shunt device trials (n = 1069), 1 atrial flow regulator trial (n = 41), 3 vagal nerve stimulation trials (n = 112), 1 baroreflex activation therapy trial (n = 21), 1 cardiac contractility modulator trial (n = 47), 6 cardiac resynchronization therapy trials (n = 178) and 2 functional electrical stimulation therapy trials (n = 89)] and 7 surgical intervention trials [1 renal denervation trial (n = 25), 3 greater splanchnic nerve ablation trials (n = 111), 2 catheter ablation trials (n = 55) and 1 pericardiotomy procedure trial (n = 4)]. One trial completed phase 3 trials, 20 trials completed phase 1 trials with further trials, and 5 trials completed phase 1 trials without further trials.

Overall, 16 out of 24 trials have at least demonstrated safety and feasibility. However, despite many trials of a medical device or surgical procedure showing proof of concept to treat HFpEF phenotypes, they do not provide sufficient evidence of long-term benefit. More robust and phenotype-based clinical trials are needed to ensure evidence-based solutions are developed in HFpEF.