NEW ORLEANS – Treatment of patients with heart failure with preserved ejection fraction (HFpEF) with the SGLT2 inhibitor dapagliflozin (Farxiga) for 24 weeks produced significant and beneficial reductions in left-heart filling pressures in a mechanistic, randomized clinical study.
The findings “provide new insight into the mechanisms underlying the favorable clinical effects of dapagliflozin in patients with HFpEF,” Barry A. Borlaug, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. “Elevations in left heart filling pressures at rest and during exercise are fundamental pathophysiologic features of HFpEF,” he noted.
Dr. Barry A. Borlaug
Results from prior studies documented the benefit of dapagliflozin for improving clinical outcomes in patients with HFpEF in the DELIVER trial, and for the related sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (Jardiance) in the EMPEROR-Preserved trial. The new findings presented by Dr. Borlaug provide evidence from a placebo-controlled, prospective study for one way by which these SGLT2 inhibitors exert this benefit in patients with HFpEF.
The results of his single-center study showed that, in patients with HFpEF who also exhibited “severe” elevations in pulmonary capillary wedge pressure (PCWP) during exercise, 24 weeks of treatment with dapagliflozin led to a significant reduction in PCWP during exercise. The treatment produced an average 6.1–mm Hg drop from baseline compared with control patients who received placebo. A similar pattern occurred when these patients were at rest, when dapagliflozin treatment linked with a significant average reduction in PCWP from baseline of 3.5 mm Hg compared with controls.
Improving a ‘specific and fundamental’ feature of HFpEF
“This fantastic study looked at one of the fundamental aspects of HFpEF,” said John R. Teerlink, MD, designated discussant for the study. “You’ve shown that dapagliflozin targets a specific and fundamental” manifestation of HFpEF by lowering PCWP, said Dr. Teerlink, director of Heart Failure at the San Francisco Veterans Affairs Medical Center.
Dr. John R. Teerlink
However, Dr. Teerlink added, the study did not directly address the related question of what physiologic action of dapagliflozin produces this notable drop in PCWP.
“We’re just starting to look at that,” replied Dr. Borlaug, a cardiologist and professor at the Mayo Clinic in Rochester, Minn.
He reported finding an intriguing correlate in the current study linked to the cut in PCWP with dapagliflozin treatment. The SGLT2 inhibitor at a standard daily 10-mg dose produced an average 3.5-kg drop in body weight in the dapagliflozin-treated patients that significantly linked with the changes in PCWP both at rest and during exercise. Dapagliflozin-treated patients also showed a significant reduction from their baseline plasma volume compared with placebo-treated patients, but this “poorly correlated” with the dapagliflozin-linked cuts in PCWP, Dr. Borlaug said.
“I don’t think this means weight loss is the cause of the hemodynamic benefit, but maybe it’s an indicator. When patients [with HFpEF] lose weight, they are in a metabolic state that leads to good changes in hemodynamics,” he suggested. “My guess is that there is probably a combination of many different little things [caused by dapagliflozin treatment of patients with HFpEF] that together result in the 20%-25% relative improvement we see in filling pressure.”