Negative component of the P in V1 greater than 1mm deep and 1mm wide or P wave duration 120 msec or greater (when seen as notched p-wave in lead II known as ‘p mitrale’).
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Negative component of the P in V1 greater than 1mm deep and 1mm wide or P wave duration 120 msec or greater (when seen as notched p-wave in lead II known as ‘p mitrale’).