[Changes in the electrocardiogram in the elderly patient. The limits between normality and pathology].

Normal electrocardiographic criteria in the elderly are not well defined. The prevalence of electrocardiographic abnormalities is three times higher in subjects over 85 years than in subjects 65-69 years old. With aging the heart rate does not vary during rest and sinus rhythm is prevalent, although sinus pauses, overall at night, are frequently seen. First degree atrio-ventricular block is present in 8.1%-19% of the elderly. 11% of subjects over 70 years suffer from left anterior hemiblock. 4.3% of subjects over 65 years and 7% of those over 85 present a right bundle branch block. 1.7% of subjects older than 65 years and 9% of those older than 85 are affected by a left bundle branch block. Atrial ectopic contractions are present in 8.8% of subjects over 60 years and in all older subjects. Atrial fibrillation is more common as age increases, being found in 2% of under 75s, in 5% of all subjects over this age, in 14% over 85 years and in 27% of patients hospitalized or institutionalized aged over 90 years. The prevalence of ventricular ectopic contractions varies from 76% in studies performed with baseline electrocardiogram to 96% in studies performed with portable monitoring electrocardiogram. Major ST-T wave alterations are present in 6.3%-13% of the elderly. In 340 patients over 80 years, hospitalized for diseases, other than cardiovascular, we found atrial fibrillation in 27.9% of subjects, ectopic beats in 26.2%, first degree atrioventricular block in 8.5%, right bundle branch block in 11.2%, left bundle branch block in 5.9%, left anterior hemiblock in 8.2%, ST-T wave alterations in 23.8% of the population.