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What is Standing increases murmur intensity in and explain in detail?
The classic ECG finding in hyperophic obstructive cardiomyopathy is large dagger-like "septal Q waves" in the lateral -- and sometimes inferior -- leads due to the abnormally hyperophied interventricular septum.. Wolff-Parkinson-White, or WPW, syndrome can be associated with HOCM The murmur that is pathognomonic for HCM is a crescendo-decrescendo holosystolic murmur best heard at the left sternal boarder. The murmur classically increases with standing and valsalva, while it decreases with squatting, hand-grip, and passive leg lift . Ref Davidson edition23rd pg 463