P-Waves Are the Main Clues for Correct ECG Interpretation

Abstract

P-wave correct interpretation may be of main importance. Its morphology and duration may help to increase the ECG sensitivity to diagnose a left ventricular hypertrophy or a diastolic dysfunction. A wide spectrum of cardiovascular and systemic disorders may involve the atria; more recently, the old atrial cardiomyopathy concept has been resumed. An atrial cardiomyopathy may lead to ugly complications such as atrial fibrillation and stroke. Recent clinical data in patients with an implanted cardiac device did show a lack of time correlation between atrial fibrillation and stroke. Thus, atrial fibrillation could be just an epiphenomenon related to abnormal atrial substrate (atrial cardiomyopathy). A recently published meta-analysis (He et al., Stroke 48:2066–72, 2017) has confirmed the association of three left atrial abnormalities easily assessable by means of a surface ECG, namely, increased P-terminal force in the precordial lead V1 (PTFV1) >40 ms mm, prolonged P-wave duration (PWD) >120 ms reflecting interatrial block and greater maximum P-wave area (PWA). Those parameters were associated not only with an increased risk of atrial fibrillation and other supraventricular arrhythmias but also of stroke. Furthermore, in patients with QRS and even repolarization abnormalities, a normal P-wave may be a good sign in favour of pseudo-abnormalities.