Right ventricular-pulmonary arterial coupling and pulmonary hypertension in hemodialysis: insights into structural cardiac changes and clinical implications

This cross-sectional analysis from the CZecking Heart Failure in patients with advanced Chronic Kidney Disease trial (ISRCTN18275480) examined pulmonary hypertension and right ventricular-pulmonary arterial coupling in patients on chronic hemodialysis. The aims of this analysis were: 1. To analyze relations between pulmonary hypertension and right ventricular-pulmonary arterial coupling with dialysis access flow and current hydration; 2. To analyze structural heart changes associated with right ventricular-pulmonary arterial uncoupling; 3. To reveal the prevalence, etiology and severity of pulmonary hypertension in the Czech hemodialysis population. We performed expert echocardiography, vascular access flow measurements, bioimpedance analysis, and laboratory testing in 336 hemodialysis patients. Pulmonary hypertension was present in 34% (114/336) patients and right ventricular-pulmonary arterial uncoupling was present in 25% of patients with pulmonary hypertension. Only weak associations between the flow of the dialysis arteriovenous access and estimated pulmonary arterial systolic pressure and right ventricular-pulmonary arterial coupling was proved. There was a strong association between hydration status assessed by estimated central venous pressure with pulmonary arterial systolic pressure (Rho 0.6, <i>p</i> &lt; 0.0001) and right ventricular-pulmonary arterial coupling (Rho −0.52, <i>p</i> &lt; 0.0001) and association between overhydration to extracellular water ratio with pulmonary arterial systolic pressure (Rho 0.31, <i>p</i> = 0.0001) and right ventricular-pulmonary arterial coupling (Rho −0.29, <i>p</i> = 0.002). The prevalence of heart failure was significantly higher in patients with right ventricular-pulmonary arterial uncoupling (88% vs. 52%, <i>p</i> = 0.0003). These findings suggest that optimizing volume status and treating heart failure should be prioritized in hemodialysis patients to prevent pulmonary hypertension progression and right ventricular-pulmonary arterial uncoupling.