ETIOLOGICAL PATTERNS AND FUNCTIONAL CLASS OF PULMONARY HYPERTENSION IN LUNG DISEASES AT A TERTIARY CARE CENTRE IN INDIA- A PROSPECTIVE STUDY.

Introduction: Pulmonary Hypertension (PH) results from multiple etiological factors, whose natural history varies considerably depending on cause and pathophysiology. The data on the etiological pattern of different lung diseases causing pulmonary hypertension is important because a high index of clinical suspicion can be kept on such patients to detect PH. Aims: To prospectively evaluate the etiological pattern of pulmonary hypertension among patients with respiratory diseases coming to our centre. We also aimed to evaluate whether etiology is a determinant of functional class in pulmonary hypertension. Materials and Methods: A prospective observational study of 53 subjects was done. All patients were interviewed about the symptoms and complete physical examination was performed. A baseline echocardiogram was done at the Dept. of Cardiology. All etiologies causing pulmonary hypertension were defined as per predetermined criteria and recorded. Clinical severity assessment was done using WHO- Functional Class, Six minute walk test and echocardiography parameters at the time of presentation. Comparison of the severity parameters were done among the etiologies.The statistical analysis was done using statistical software SPSS Version 16. Results: In this study, the most common etiology of pulmonary hypertension in lung diseases was Chronic Obstructive Pulmonary Disease(51%) followed by Interstitial lung diseases(22%) and Bronchiectasis (17%). Majority of our patients presented with WHO- Functional class- 3. As part of the severity assessment, COPD patients were found to have a significantly low RVSP (Right Ventricular Systolic Pressure) values when compared to other etiologies. There was no significant difference in six minute walk distance and functional performance among the various etiologies. Conclusions: In this study, the most common etiology of pulmonary hypertension in lung diseases was Chronic Obstructive Pulmonary Disease. Most of the patients with Pulmonary Hypertension presented with worse functional performance. COPD patients had a milder pulmonary hypertension when compared to other etiologies.