presence of tricuspid regurgitation it gives an estimate of systolic pulmonary artery pressure, which has been found to correlate well with pressure measured by ...
ORIGINAL ARTICLE
Noninvasive Estimation of Clinically Asymptomatic Pulmonary Hypertension in Idiopathic Pulmonary Fibrosis R. Agarwal, D. Gupta, J.S. Verma1, A.N. Aggarwal and S.K. Jindal Departments of Pulmonary Medicine and Cardiology1, Postgraduate Institute of Medical Education and Research, Chandigarh, India
ABSTRACT Objectives. To determine the prevalence of pulmonary hypertension in patients with idiopathic pulmonary fibrosis (IPF) by noninvasive methods. Patients and Methods. Twenty seven patients with IPF attending the Chest Clinic over a period of one-and-a-half-years underwent echocardiography for evidence of pulmonary hypertension, which was defined as pulmonary artery systolic pressure ≥ 40 mmHg by Doppler echocardiography, or pulmonary acceleration time ≤ 100 milliseconds or two-dimensional echocardiographic findings of right ventricular hypertrophy or overload. Results. Two patients with clinical evidence of pulmonary hypertension were excluded from analysis. Their mean age (n=25) was 53.8 years. The mean duration of symptoms before presentation was 2.1 years. Pulmonary hypertension was diagnosed by echocardiography in nine of the 25 patients (36%). There was a statistically significant difference between the duration of illness, arterial oxygen tension (PaO2) levels and forced vital capacity in patients with pulmonary hypertension than in those without pulmonary hypertension. Logistic regression analysis showed a significant association between the duration of illness, decreasing forced vital capacity and hypoxemia with the development of pulmonary hypertension. Conclusions. Echocardiography detects pulmonary hypertension in clinically asymptomatic individuals, and should be used routinely for the diagnosis of pulmonary hypertension in patients with IPF. Key words: Idiopathic pulmonary fibrosis, Pulmonary hypertension, Echocardiography.
[Indian J Chest Dis Allied Sci 2005; 47: 267-271]
INTRODUCTION Idiopathic pulmonary fibrosis (IPF) is an inflammatory interstitial disease of unknown origin. It presents with non-specific symptoms of dyspnea and dry cough. Glucocorticoids and/ or cytotoxic agents are the mainstay of therapy,
but fewer than 30% respond to existing therapies and toxicities are substantial1-4. Most patients have a relentlessly progressive course eventually developing respiratory failure and congestive heart failure. Until recently, most patients used to succumb
[Received: July 20, 2004; accepted after revision: November 25, 2004] Correspondence and reprint request: Dr S.K. Jindal, Professor and Head, Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh-160 012, India; Tele.: 91-0172-2756821, Telefax: 91-0172-2745959; E-mail: .
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to respiratory failure, often precipitated by infection long before the development of pulmonary hypertension and chronic corpulmonale. But with the use of more specific immunosuppressive and other supportive therapies, many patients live long enough to develop cardiovascular and other related problems 5. There is, however, little data on cardiac involvement in IPF, particularly from India. In this study, we describe the prevalence of pulmonary hypertension in clinically asymptomatic patients with IPF.
PATIENTS AND METHODS Patients with idiopathic pulmonary fibrosis (IPF) of either sex fulfilling the American Thoracic Society criteria3 were enrolled in this study. The algorithm which was used for diagnosis of IPF has been previously described6. Inclusion criteria included history of dyspnoea on exertion for three months, bi-basal endinspiratory crackles on auscultation, abnormal pulmonary function tests that included evidence of restriction [reduced forced vital capacity (FVC) with normal to increased forced expiratory volume in one second (FEV 1) to forced vital capacity ratio (FVC)] or impaired gas exchange (decreased diffusing capacity for carbon-monoxide (DL CO ), high-resolution computed tomograhy (HRCT) scans typical of IPF, transbronchial lung biopsy (TBLB) or bronchoalveolar lavage (BAL) showing no features to support an alternative diagnosis. Patients with known causes of interstitial lung diseases like drugs, environmental exposure, connective tissue diseases or known causes of pulmonary hypertension, such as mitral valve disease, chronic pulmonary thromboembolism, and primary pulmonary hypertension were excluded. In all patients, a detailed clinical examination was performed to look for signs of pulmonary hypertension. Dyspnoea was graded using the Medical Research Council (MRC) scale 7. All patients underwent arterial blood gas analysis on room air after 30 minutes of rest. Electrocardiographic (ECG) findings of right ventricular enlargement: R>S in V1 or V2, right axis deviation >110 degrees, R11 mm was recorded. Chest radiographic (CXR) signs of pulmonary hypertension (dilatation of pulmonary artery, increased cardiothoracic ratio) and presence and extent of pulmonary fibrosis were recorded. On spirometry, FEV1/ FVC ratio >70% with FVC
