PULMONARY ARTERIOVENOUS MALFORMATION - PROGRESSIVE ENLARGEMENT WITH REPLACEMENT OF THE ENTIRE RIGHT MIDDLE LOBE IN A PATIENT WITH CONCOMITANT MITRAL-STENOSIS

Objective: To present a case of pulmonary arteriovenous malformation ( AVM) that showed progressive enlargement in a patient with concomitant rheumatic mitral stenosis. Clinical features: A 73-year-old woman fir st presented eight years ago because of an uncomplicated acute myocard ial infarction. She was noted to have rheumatic mitral stenosis. Six y ears later, she developed symptomatic sick sinus syndrome for which a permanent pacemaker was implanted. Chest x-ray revealed new developmen t of an opacity in the middle zone of the right lung. Two years later, she was admitted to hospital because of progressive dyspnoea. Chest x -ray showed further increase in size of the right middle zone opacity. Outcome: She died of cardiopulmonary failure on the 18th day in hospi tal. Autopsy revealed a pulmonary AVM, replacing the entire right midd le lobe. Conclusion: The elevated pulmonary vascular resistance caused by mitral stenosis may have increased the preferential flow of blood through the AVM, leading to its rapid enlargement. Patients with conco mitant pulmonary AVM and mitral stenosis need to be recognised, as clo se follow-up and early treatment may be desirable.