Primary inflammatory disease in heart failure with preserved ejection fraction

Abstract

Abstract Background Inflammation plays a fundamental role in the pathogenesis of heart failure (HF) with preserved ejection fraction (HFpEF). In most patients, inflammation develops secondary to cardiometabolic comorbidities, but in some, HFpEF develops in the setting of underlying systemic inflammatory diseases represented by rheumatoid arthritis. Purpose This study aimed to investigate the prevalence, pathophysiology, and outcome of patients with HFpEF and primary inflammatory diseases. Methods Consecutive patients undergoing hemodynamic exercise testing with concurrent expiratory gas analysis to evaluate dyspnea of unknown cause were identified. HFpEF was defined as left ventricular ejection fraction ≥50% and pulmonary capillary wedge pressure ≥15 mmHg (rest) or ≥25 mmHg (exercise). Patients with HFpEF were divided into groups with and without primary inflammatory diseases. Patients without inflammatory disease were divided into tertiles according to the value of C-reactive protein (CRP). Results Of 982 consecutively evaluated patients with HFpEF diagnosed (577 female, mean age 68 years), 79 (8%) had primary inflammatory disease. In multivariable logistic regression, female sex (OR 1.88; 95% CI 1.01-3.52), higher resting heart rate (OR 1.18; 95% CI 1.08-1.30), lower hemoglobin level (OR 0.84; 95% CI 0.70-0.99), absence of history of atrial fibrillation (OR 0.45; 95% CI 0.24-0.86) and absence of epicardial coronary artery disease (OR 0.45; 95% CI 0.22-0.93) were independently associated with inflammatory disease. Hemodynamics at rest and exercise did not differ between the groups, but peripheral oxygen extraction was lower in those with inflammatory disease, reflected by lower arterial-venous oxygen content difference (Ca-vO2) at rest (4.2±0.7 mL/dL vs 4.6±1.0 mL/dL, P<.001) and during exercise (9.3±2.2 mL/dL vs 10.4±2.2 mL/dL, P<.001) (Figure 1A), suggesting a greater peripheral deficit, and ventilatory efficiency (VE/VCO2 slope) was also more impaired (38.0±7.9 vs 36.2±7.3, P=.035). The HFpEF patients without inflammatory disease falling in the highest tertile of CRP) displayed lower Ca-vO2 during exercise, more closely resembling peripheral deficits observed in those with inflammatory disease (Figure 1B). During a median follow-up of 3.0 years, the composite outcome of all-cause deaths and HF hospitalization occurred in 127 patients (14%). Patients with HFpEF and inflammatory disease showed a higher incidence of composite outcome than those without (log-rank P=.030; Figure 2). Patients with inflammatory disease had higher risk of composite outcome compared to those without in adjusted analyses (HR 1.93; 95% CI 1.15-3.23), which was primarily attributable to higher risk of HF hospitalization (HR 2.85; 95% CI 1.08-7.52). Conclusion Patients with HFpEF and primary inflammatory disease have similar hemodynamic derangements but greater peripheral deficits in oxygen transport and higher risk for adverse outcome compared to those without.