Invasive Hemodynamic Predictors of Mortality in High-Output Heart Failure

BACKGROUND: High-output heart failure (HOHF) is a distinct form of HF characterized by elevated cardiac output yet persistent volume overload. Few data exist on how invasive hemodynamic parameters relate to clinical outcomes in HOHF. To investigate the relationship between key invasive hemodynamic measures and all-cause mortality in patients with HOHF. METHODS AND RESULTS: We retrospectively analyzed 248 adults (≥18 years) who underwent elective right heart catheterization between July 2015 and September 2023 and met the criteria for elevated cardiac index (CI) (≥4 L/min/m²) and elevated filling pressures. The primary end point was all-cause mortality. Over a median follow-up of 3.3 years, 57 patients died. The 6-month, 1-year, and 3-year survival rates were 90.7%, 87.5%, and 82.9%, respectively. In a multivariable analysis adjusted for demographics, comorbidities, and key hemodynamic variables, cardiac index (CI) was the strongest predictor of mortality (hazard ratio [HR] 1.87, 95% confidence interval 1.41-2.48, P < 0.001). Other key variables associated with mortality were right atrial pressure (HR 1.30 per 5 mm Hg, 95% confidence interval, 1.01-1.68, P = 0.039), and mean arterial pressure (HR 0.97, 95% confidence interval, 0.95-0.99, P = 0.02), and systemic vascular resistance (HR 0.70 per 100 dyn·s/cm⁵, 95% confidence interval, 0.59-0.84, P < 0.001). Pulmonary artery wedge pressure, pulmonary arterial pulsatility index, and pulmonary artery pressures were not independently associated with mortality. CONCLUSIONS: An elevated CI is the most significant hemodynamic predictor of all-cause mortality in HOHF. This finding suggests that hemodynamic assessment can help to stratify risk in patients with HOHF, and that therapies designed to modulate hemodynamics may improve outcomes in this high-risk population.