Occult pulmonary arterial hypertension in patients with previous pulmonary tuberculosis

BACKGROUND: Pulmonary tuberculosis (TB) still causes a significant public healthcare burden. Despite successful treatment, TB can lead to permanent lung damage and pulmonary hypertension (PH). PH can also occur in the absence of significant lung damage, leading clinicians to question whether pulmonary TB may cause pulmonary arterial hypertension (PAH), an entity that has not been otherwise described. OBJECTIVES: To determine the prevalence of PAH in patients previously treated for TB. METHODS: We recruited 20 participants who were previously treated for TB and had no other underlying risk factors for the development of PH. The participants underwent electrocardiography (ECG), chest radiography, lung function tests and echocardiography (ECHO). Data from these non-invasive investigations were evaluated to determine findings that were suggestive of PH. RESULTS: At a median duration of 30 months from diagnosis of TB, no participant had echocardiography findings that were suggestive of PH (pulmonary artery pressure (PAP) ≥40 mmHg). However, there was a negative correlation between the time from diagnosis and right ventricular dysfunction assessed by measuring a tricuspid annular plane systolic excursion (r=–0.5136; p=0.0205). Furthermore, one-third of the participants (n=7) had one or more ECG features supporting PH and 85% of the participants (n=17) demonstrated at least one chest X-ray (CXR) feature of PH. CONCLUSION: Although our study did not demonstrate ECHO findings supporting PH, ECG and CXR modalities were suggestive. Therefore, future studies consisting of larger cohorts and including the use of other sensitive modalities such as computed tomography are warranted. Moreover, these studies will need to determine whether the entity of PAH secondary to previously treated pulmonary TB exists.