Evaluation of pulmonary hypertension in stable chronic obstructive pulmonary disease patients using transthoracic echocardiography

Background: Pulmonary hypertension (PH) frequently complicates chronic obstructive pulmonary disease (COPD) process and adversely affects the exercise capacity of such patients. However, majority of the COPD patients are not routinely evaluated for PH even though a rapid screening tool in the form of transthoracic echocardiography (TTE) is available for the early diagnosis of PH. This study was conducted with an aim to study the frequency and severity of PH among stable COPD patients. Materials and Methods: Fifty stable COPD patients who met the inclusion criteria were selected and staged for severity by spirometry and screened for PH using TTE. Tricuspid regurgitation jet velocity obtained was used to calculate systolic pulmonary artery pressure (sPAP). Mean pulmonary artery pressure was calculated from sPAP using Chemla formula. Results: (1) The frequency of PH in COPD patients was 48% (24 out of 50). The frequency of PH in patients of mild, moderate, severe, and very severe GOLD COPD stages was 12.5% (1/8), 45.83% (11/24), 61.53% (8/13), and 80% (4/5), respectively. (2) Out of the 24 patients with PH, the relative incidence of mild (25-35 mmHg), moderate (35-45 mmHg), and severe (>45 mmHg) PH was 54.16% (13/24), 29.16% (7/24), and 16.67% (4/24), respectively. Only one patient had "out-of-proportion" PH. Conclusion: PH is an underdiagnosed entity that frequently complicates the course of disease in COPD patients and adversely affects exercise capacity. TTE is an accurate, noninvasive screening tool for PH and should be routinely used in all COPD patients for early diagnosis of PH.