Hemodynamic Variables in Pulmonary Hypertension Due to Left Heart Disease

Pulmonary hemodynamics may have incremental prognostic value for risk prediction in pulmonary hypertension due to left heart disease (PH-LHD), according to a study published in BMC Cardiovascular Disorders.

Investigators sought to evaluate the prognostic value of established risk prediction strategies for pulmonary arterial hypertension (PAH) and heart failure in patients with PH-LHD. They also assessed other outcome correlates and the incremental prognostic value of pulmonary hemodynamics in risk prediction for PH-LHD.

The multicenter, prospective registry study enrolled patients with symptomatic chronic heart failure undergoing first right heart catheterization during hospitalization from January 2013 to August 2016 in China. All-cause mortality was the primary endpoint.

A total of 276 patients with post-capillary PH were included. Their mean age was 63.2±12.4 years, 71.7% were men, 28.6% had heart failure with reduced ejection fraction, and 71.4% had heart failure with preserved ejection fraction.

After a median follow-up of 34.7 months (IQR, 17.77-39.63), 53 patients died. The 3-year survival estimate was 79.3% (95% CI, 74.3%-84.8%).

Diastolic pressure gradient (DPG) and mixed venous oxygen saturation (SvO₂) were the hemodynamic predictors most strongly associated with mortality (coefficient: 0.0255 and -0.0176, respectively), according to the L1-Penalized Regression Model and random forest approach.

After adjustment with the Seattle Heart Failure Model (SHFM) risk score, DPG (hazard ratio [HR] 1.067; 95% CI, 1.024-1.113, P =.022) and SvO₂ (HR 0.969; 95% CI, 0.953-0.985; P =.002) were the only significant predictors for all-cause mortality. After adjustment with the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) score, diastolic pulmonary arterial pressure (HR 1.281; 95% CI, 1.097-1.495; P =.022), DPG (HR 1.069; 95% CI, 1.026-1.114; P =.011), cardiac index (HR 1.792; 95% CI, 1.228-2.615; P =.022), and SvO₂ (HR 0.970; 95% CI, 0.954-0.986; P =.004) were independent predictors for mortality.

As a result of these analyses, DPG and SvO₂ were then included in the SHFM or MAGGIC scores to identify their incremental prognostic value. The inclusion of DPG and SvO₂ improved risk prediction vs the models that only involved the SHFM (net reclassification improvement [NRI]: 0.468 [0.161-0.752]; integrated discriminatory index [IDI]: 0.092 [0.035-0.171]; likelihood ratio [LR] test: P <.001) or MAGGIC (NRI: 0.298 [0.106-0.615]; IDI: 0.084 [0.033-0.151]; LR test: P <.001) scores.

Among several study limitations, inherent patient selection bias is possible due to the relatively small sample size. Other limitations include the small number of events and the lack of data on dose of diuretics used.

“The present study has validated the performance of [4] established PH or [heart failure] risk prediction strategies in patients with PH-LHD, and has identified a broad range of variables, including demographics, clinical assessments, biomarkers, and hemodynamics, associated with all-cause mortality of PH-LHD,” the researchers wrote.

Reference

Quan R, Huang S, Pang L, et al. Risk prediction in pulmonary hypertension due to chronic heart failure: incremental prognostic value of pulmonary hemodynamics. BMC Cardiovasc Disord. Published online February 16, 2022. doi: 10.1186/s12872-022-02492-1