[Role of standard resting ECG in the assessment of sudden cardiac death risk]

Today the ECG is still, over 100 years after its invention (Willem Einthoven 1903), the most commonly used diagnostic procedure in clinical cardiology. In recent years, we have accumulated knowledge that has significantly expanded the diagnostic possibilities of ECG, through the recognition of patterns associated with a number of primary electrical diseases of the myocardium, the so-called inherited arrhythmogenic diseases. These clinical entities are caused by gene mutations that determine a substrate leading to the onset of life-threatening rhythm disturbances. The study of ECG abnormalities in these diseases showed characteristic phenotypic traits, which in combination with information derived from molecular genetics, have allowed using the ECG as a prognostic tool as well as a diagnostic test. The assessment of genotype-phenotype correlations in inherited arrhythmogenic diseases has allowed to advance the idea of the ECG as an inheritable trait. Such heritable quantitative traits are potentially related to the risk of sudden death in the general population, which is known to have a familial predisposition. This article summarizes the pathophysiology and phenotypic manifestation of the main arrhythmogenic diseases. Also shown are current possibilities and limitations of the use of a simple and low-cost technology, not only as a tool for diagnosis but also as a tool to identify prognostic markers. We will show how, rather surprisingly, the ECG often allows extracting the most important information for appropriate risk classification and clinical management.