Limitations of right heart catheterization in the diagnosis and risk stratification of patients with pulmonary hypertension related to left heart disease: insights from a wireless pulmonary artery pressure monitoring system

Abstract

Background: Although right heart catheterization (RHC) remains the gold standard for assessment of hemodynamics in patients with known or suspected pulmonary hypertension (PH), there are significant limitations to this type of assessment. The current study evaluates the limitations of RHC in the diagnosis of left heart-related PH (World Health Organization group II) among patients enrolled in the CHAMPION trial and discusses insights into patient risk from home implantable hemodynamic monitor (IHM) data that were not identified at the time of the RHC procedure.

Methods: The CHAMPION trial enrolled 550 New York Heart Association functional class III patients who had been hospitalized for heart failure (HF) in the previous year, regardless of left ventricular ejection fraction or etiology. Hemodynamic data obtained during baseline RHC were compared with IHM data obtained during the first week of home readings. HF hospitalization rates and mortality were analyzed to assess patient risk.

Results: The study population for this retrospective analysis comprised 537 patients with available IHM data. For 320 patients in the PHRHC group, home IHM data confirmed the RHC findings with similar mean pulmonary artery pressures obtained from both methods (36 mm Hg vs 36 mm Hg, p = 0.5066). However, of the 217 patients in the No PHRHC group, 106 patients (48.8%) exhibited PH based on the home IHM data (PHIHM group). The remaining 111 patients (51.2%) in the No PHRHC group had no evidence of PH on the IHM data (No PHIHM group). Patients in the No PHRHC/PHIHM group had significantly higher mean PA pressures on IHM than patients in the No PHRHC/No PHIHM group (31 mm Hg vs 18 mm Hg, p < 0.0001). Patients in the No PHRHC/No PHIHM group had significantly lower HF hospitalization rates than patients in the No PHRHC/PHIHM group (0.25 vs 0.49, incidence rate ratio = 0.51, 95% confidence interval = 0.33-0.77, p = 0.0007).

Conclusions: Using only RHC, World Health Organization group II PH may be significantly under-diagnosed. In patients with left-sided HF and resting mean PA pressure ≤25 mm Hg during RHC, more frequent PA pressure monitoring using an IHM device can provide additional data for improved diagnosis and patient risk stratification compared with a single RHC alone.

Trial registration: ClinicalTrials.gov NCT00531661.

Keywords: heart failure; hemodynamic monitoring; hospitalization; mortality; pulmonary hypertension; risk stratification.