Ophthalmologists can play a pivotal role in detection and treatment of life-threatening disorders by recognizing syndromes associated with retinal tumors. Ophthalmologists can play a pivotal role in detection and treatment of life-threatening disorders by recognizing syndromes associated with retinal tumors.
The P wave in the ECG represents atrial depolarization, which results in atrial contraction.
When left atrial enlargement occurs, it takes longer for cardiac action potentials to travel through the atrial myocardium; thus, the P wave also lengthens. Therefore, the criteria for diagnosing LAE on a 12-lead ECG is as follows: 1  The length of the P wave in lead II is greater than 120 milliseconds. OR. 2  The downward deflection of the P wave in lead V1 is greater than 40 milliseconds in length, with greater than 1 millimeter negative deflection (< -1 mm in amplitude)