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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Most common site of subclan aery stenosis is in pa:
assistant
The correct answer is  Subclan Aery is most commonly obstructed in the proximal poion -1st pa proximal to the origin of veebral and internal thoracic aery. It is focal and is usually an extension of atherosclerotic narrowing from the aoic arch into the aery. The stenosis is more common on left side - Left subclan is involved 3 times more frequently involved than the right.