RHC is still recommended over echocardiography for the detection of COPD-PH

Echocardiography has a high specificity in the diagnosis of pulmonary hypertension (PH) in patients with advanced chronic obstructive pulmonary disease (COPD); however, it has little specificity for the detection of PH in these patients, according to a recent study published in The American Journal of the Medical Sciences.

Detection of PH in patients with COPD is critical. Patients with COPD combined with PH carry increased risks for hospitalizations, mortality and other exacerbations, and their PH status may affect candidacy for lung transplantation.

Right heart catheterization (RHC) is the typical approach for the diagnosis of PH, but the use of echocardiography could provide many benefits to patients. Comparatively, echocardiography is less expensive and invasive, and works well in screening the patient’s pulmonary arterial pressure (PAP); however, the effectiveness of this approach in the identification of PH in patients with COPD has not been sufficiently studied. In addition, RHC is currently trusted for multiple transplant criteria, including transplant list management, identification and treatment of left-sided heart disease, and decision-making for lung transplants. single or double. To address this gap, researchers conducted a study to evaluate the utility of echocardiography as a less invasive diagnostic tool for PH in patients with COPD.

Patients with COPD who were evaluated for lung transplantation who also underwent RHC for the diagnosis of PH were evaluated between January 2011 and May 2019. Echocardiograms were performed at a median of 3 days from the time of RHC , with most of the former (76%). Individuals were classified as having a low, intermediate, or high probability of PH according to their tricuspid regurgitation velocity (TVR) and the presence of echocardiographic evidence of PH. Echocardiographic criteria for PH include at least 2 of the following: detection of a right/left ventricular basal diameter ratio above 1, flattening of the interventricular septum, right ventricular flow Doppler acceleration time below 105 m/ s, mid-systolic notching, or early diastolic pulmonary. regurgitation speed above 2.2 m/s^-1.

A total of 111 patients with severe COPD (defined according to the 6th World Symposium of Pulmonary Hypertension) who received RHC were evaluated. Of these 111, 82 patients were identified with COPD-PH (74%). Overall, patients had a mean PAP (mPAP) of 30.3 mm Hg, systolic PAP (sPAP) of 45.8 mm Hg, diastolic PAP (dPAP) of 21.8 mm Hg, pulmonary vascular resistance (PVR) of 4.0 mm Hg, diastolic pulmonary gradient (PVR). DPG) of 8.5 mm Hg, right arterial pressure (RAP) of 9.7 mm Hg, and pulmonary capillary wedge pressure (PCWP) of 13.5 mm Hg. Those with COPD-PH were noted to have significantly higher PAP levels compared to those without.

According to echocardiographic criteria, 20 patients (18%) had a high probability of PH, 20 (18%) had intermediate, and 71 (64%) had low. In these cases, the sensitivity, specificity, positive and negative predictive values ​​for diagnostic echocardiography COPD-PH were 43%, 83%, 88% and 34%, respectively. Furthermore, for the diagnosis of severe COPD-PH, these values ​​were 67%, 75%, 50% and 86%.

In light of their findings, the authors note that echocardiography’s high specificity and positive predictive values ​​demonstrate its value in the diagnosis of COPD-PH; however, it showed limited sensitivity to exclude COPD-PH and its effectiveness was influenced by the presence of significant hyperinflation or severe emphysema in these patients. The authors conclude by stating that their results were not consistent with the recommendations to identify COPD-PH with non-invasive methods for advanced COPD; therefore, pretransplant RHC should always be considered.

Reference

Younis M, Al-Antary N, Dalbah R, et al. Echocardiography and pulmonary hypertension in patients with chronic obstructive pulmonary disease undergoing evaluation for lung transplantation. Am J Med Sci. Published online November 13, 2023. doi:10.1016/j.amjms.2023.11.006