Heart Failure with Preserved Left Ventricular Ejection Fraction: A Complex Conundrum Simply Not Limited to Diastolic Dysfunction

Obesity/cardiometabolic phenotype of heart failure with preserved ejection fraction: mechanisms to recent trials

PURPOSE OF REVIEW

Heart failure with preserved ejection fraction (HFpEF) is a leading and growing cause of morbidity and mortality globally. Of the various phenotypes identified, the obesity (or cardiometabolic) phenotype appears to be most common. The purpose of this review is to provide the clinician with an abridged understanding of recent developments that have elucidated obesity/visceral adiposity as a central mechanism linking inflammation/immune dysregulation to the development of the HFpEF syndrome. Recent clinical trials examining the efficacy of pharmacological treatments that target obesity in HFpEF will also be discussed.

RECENT FINDINGS

Recent data indicate that visceral adiposity and insulin resistance in HFpEF serve as key mechanisms driving inflammation and immune dysregulation, which play a critical role in the development of cardiac stiffness, diastolic dysfunction and fibrosis in HFpEF. In obesity, alterations in macrophage polarization, changes in innate and adaptive immune systems and altered myocardial energetics promote metabolic inflammation in HFpEF. Finally, emerging data suggest that inflammatory biomarkers, specifically, IL-6, may provide useful information about HFpEF severity and symptom burden in obesity.

SUMMARY

The obesity phenotype of HFpEF is seen in upward of 80% with HFpEF. Obesity is not just a bystander, but plays an essential role in the pathobiology and clinical course of HFpEF. Targeting overweight/obesity in HFpEF with GLP-1 receptor agonists holds promise in these patients.

Obesity-Induced Hyperglycemia and Heart Failure Preserved Ejection Fraction: Uncharted Territories to Remission

Until the end of World War II, food security was a global challenge. Consequently, in 1948, type 2 diabetes was relatively uncommon, with the majority of cases being type 1 diabetes requiring insulin therapy. Since then, food has become increasingly palatable and readily available, leading to a rise in obesity across all age groups. Understanding the impact of obesity on our health has become crucial for optimizing healthcare. In this context, we draw attention to two significant, yet relatively uncharted pathogenic effects associated with obesity: Hyperglycemia and Heart Failure with Preserved Ejection Fraction (HFpEF). Thorough pathophysiologic, hemodynamic, and echocardiographic characterization have revealed the existence of a distinct phenotype known as "obese HFpEF" within the broader HFpEF population, and "obesity-induced hyperglycemia" within the diabetes population. In these phenotypes, patients often present with higher Body Mass Index and experience clinical symptoms decades earlier. Recent insights have enhanced our understanding of the mechanisms underlying obesity-mediated heart failure preserved ejection fraction and hyperglycemia. Early detection offers the potential for reversibility of many pathologies associated with obesity through adequate weight reduction. The objective of this review is to provide a deeper insight into these uncharted territories and explore the potential for improved outcomes by reframing these two narratives toward achieving remission. Such a shift has the potential to positively impact individual engagement with healthier lifestyles.