Association of Pulmonary Artery Compliance and Adverse Cardiac Events

Pulmonary artery compliance (PAC), the ratio of stroke volume to pulmonary artery pulse pressure, reflects the pulsatile component of right ventricular afterload and is associated with right heart failure (HF) and death in pulmonary arterial hypertension.

The authors examined the association of PAC with clinical outcomes in individuals with a broad range of cardiopulmonary comorbidities.

The authors examined ambulatory and hospitalized patients undergoing right heart catheterization at a single center (2005-2016). The association of PAC with HF hospitalization and mortality was investigated with multivariable Cox models. Analyses were stratified by the presence and absence of pulmonary hypertension (PH) and PH hemodynamic subtype.

Among 7,966 patients (mean age 63 years, 39% women), the median PAC was 3.29 mL/mm Hg (Q1-Q3: 2.19-4.70 mL/mm Hg). PAC was inversely associated with mortality (HR: 0.59 per 1-SD higher PAC; 95% CI: 0.56-0.63) and HF hospitalization (HR: 0.56; 95% CI: 0.52-0.59) across the whole sample and among those with PH (mortality: HR: 0.69; 95% CI: 0.64-0.74, HF: HR: 0.65; 95% CI: 0.61-0.70) and without PH (mortality: HR: 0.74; 95% CI: 0.66-0.84, HF: HR: 0.72; 95% CI: 0.61-0.85). Similarly, PAC was associated with mortality across PH subtypes: precapillary PH (HR: 0.56; 95% CI: 0.48-0.65), combined PH (HR: 0.75; 95% CI: 0.66-0.86) and postcapillary PH (HR: 0.88; 95% CI: 0.79-0.98).

Among patients undergoing right heart catheterization, lower PAC is associated with adverse outcomes irrespective of PH status. Our findings support the utility of PAC in risk stratification across cardiopulmonary disease.