Evidence Fails to Support ECG Screening for Those Without Heart Disease Symptoms

Abstract

PHYSICIANSDOINGROUTINEPHYSICAL examinationsonolder individuals frequently call for a resting or exerciseelectrocardiogram(ECG)todetect heartabnormalities.Althoughscreening ECGsinasymptomaticindividualsdodetectabnormalitiesassociatedwithhigher riskforadversecardiovascularevents,rigorous evidence is lacking to determine whether such tests actuallychangeclinical actions and improve outcomes, said authors of a 2011 review (Chou R et al. Ann Intern Med. 2011;155[6]:375-385). The review, requested by the US PreventiveServicesTaskForce,reaffirmsthe 2004 recommendation by the task force againstscreeningwithrestingorexercise ECG in adults at low risk for coronary heart disease. Roger Chou, MD, lead author of the reviewandanassociateprofessorofmedicineatOregonHealth&ScienceUniversityinPortland,saidhisteam’smainfocus was to understand what added benefit ECG would provide over traditional Framingham risk assessment to physicians evaluating patients. Framingham riskassessment isbasedonascoringsystemthatcalculatesanindividual’s10-year percentage risk of myocardial infarction or coronary death based on age, sex, levels of total and high-density lipoprotein cholesterol, smoking status, and blood pressure readings. Individuals are stratified to 3 risk levels: low ( 10%), intermediate (10%-20%), or high ( 20%). The reviewers looked at 65 Englishlanguage articles published from 2002 through January 2011 and found that none addressed whether ECG screening improved outcomes, affected clinical decision making, or improved Framingham risk reclassification. They included 2 studies looking at direct harms from ECG screening and found the test safe. The 63 studies addressing ECG findings and risk for cardiovascular events showed that abnormalities on resting ECG or exercise ECG were associated with increased risk. “We wanted to understand how the ECG findings would affect clinical