The leading cause of death in the United States is coronary heart disease (CHD). In 2004,  the US Preventive Services Task Force (USPSTF) recommended against electrocardiogram  (ECG) in asymptomatic adults. Besides, ECG is not recommended as part of periodic health examinations, according to the American Academy of Family Physicians. This report from the USPSTF updates the 2004 recommendations on ECG screening for asymptomatic adults at low, intermediate, or high risk for CHD events.

 

You can see herein below the whole article published by MedScape / August 2012
News Author: Laurie Barclay, MD
CME Author: Penny Murata, MD

Recommends Against Routine Electrocardiogram Screening CME/CE

News Author: Laurie Barclay, MD
CME Author: Penny Murata, MD
CME/CE Released: 08/17/2012; Valid for credit through 08/17/2013

Clinical Context

The leading cause of death in the United States is coronary heart disease (CHD), as previously reported by Xu and colleagues (Natl Vital Stat Rep. 2010;58:1-117). In 2004, the US Preventive Services Task Force (USPSTF) recommended against electrocardiogram (ECG) or electron-beam computed tomography screening for CHD in asymptomatic adults at low risk for CHD events and found insufficient evidence to make recommendations about ECG screening in asymptomatic adults at intermediate and high risks for CHD events.

Greenland and colleagues (Circulation. 2010;122:2748-2764) previously reported the American College of Cardiology Foundation and the American Heart Association guidelines that resting ECG for cardiovascular risk assessment in asymptomatic adults with hypertension or diabetes was reasonable and that exercise ECG for cardiovascular risk assessment in asymptomatic intermediate-risk adults may be considered.

ECG is not recommended as part of periodic health examinations, according to the American Academy of Family Physicians.

This report from the USPSTF updates the 2004 recommendations on ECG screening for asymptomatic adults at low, intermediate, or high risk for CHD events and excludes electron-beam computed tomography screening recommendations, which have been published separately.

Study Synopsis and Perspective

The USPSTF reaffirms its 2004 recommendation against routine ECG screening for asymptomatic adults at low risk for CHD, according to updated guidelines published online July 31 in the Annals of Internal Medicine.

«[CHD] is the leading cause of death in the United States in both men and women, accounting for nearly 40% of all deaths each year,» write USPSTF chair Virginia A. Moyer, MD, MPH, from Baylor College of Medicine in Houston, Texas, and colleagues. «More than 1 million Americans experience nonfatal or fatal myocardial infarction (MI) or sudden death from CHD annually. For some people, this event is the first manifestation of the presence of CHD.»

The 2004 USPSTF statement cited a lack of evidence to suggest that ECG screening in asymptomatic, low-risk adults would improve health outcomes, and accordingly, the USPSTF recommended against routine ECG screening for asymptomatic adults at low CHD risk. The task force based its current recommendations on evidence available since 2004.

Benefits and Harms

After adjustment for known CHD risk factors, several resting and exercise ECG abnormalities are associated with increased risk for a serious CHD event, according to adequate evidence reviewed by the USPSTF. However, evidence was inadequate to conclude that adding ECG findings to conventional risk factor evaluation would improve classification of individuals into high-, intermediate-, or low-risk groups to facilitate risk management.

According to the epidemiology and natural history of CHD, as well as treatment regimens using risk stratification, the USPSTF concluded that evidence was inadequate to measure the degree to which additional information from resting or exercise ECG would change risk stratification and associated treatment. Therefore, the USPSTF could not determine whether such additional information would lower the number or severity of CHD-related events.

Potential harms of screening asymptomatic adults with resting or exercise ECG are at least small, according to evidence described as «adequate» by the USPSTF. These harms include unnecessary invasive procedures, overtreatment, and diagnostic mislabeling.

«The USPSTF concludes with moderate certainty that the potential harms of screening for CHD with exercise or resting ECG equal or exceed the potential benefits in asymptomatic adults at low risk for CHD events,» the task force writes.

«The USPSTF concludes that the evidence is lacking and the balance of benefits and harms of screening for CHD with exercise or resting ECG in asymptomatic adults at intermediate or high risk for CHD events cannot be determined.»

USPSTF Recommendations

For asymptomatic adults at low risk for CHD events, the USPSTF recommends against screening with resting or exercise ECG to predict CHD events. This is a D recommendation.

To predict CHD events in asymptomatic adults at intermediate or high risk for CHD events, current evidence reviewed by the USPSTF is insufficient to weigh the benefits against the harms of screening with resting or exercise ECG. This is an I statement.

«While there is insufficient evidence to determine whether screening adults at increased risk is beneficial, those who are at intermediate risk for CHD events have the greatest potential for net benefit from ECG screening,» the task force concludes.

«Reclassification into a higher risk category might lead to more intensive medical management that could lower the risk for CHD events, but it might also result in harms, including medication adverse effects such as gastrointestinal bleeding and hepatic injury. The risk-benefit tradeoff would be most favorable if persons can be accurately reclassified from intermediate to high risk.»

The USPSTF members have disclosed no relevant financial relationships.

Ann Intern Med. Published online July 31, 2012.

STUDY HIGHLIGHTS

  • Screening with resting or exercise ECG to predict CHD events in asymptomatic adults at low risk for CHD events is not recommended.
  • Insufficient evidence exists to make a recommendation about ECG screening to predict CHD events in asymptomatic adults at intermediate or high risk for CHD events.
  • Resting and exercise ECG abnormalities are linked with an increased risk for a serious CHD event, after controlling for risk factors.
  • Not enough evidence is available that ECG added to conventional risk factors will improve stratification into low-, intermediate-, or high-risk groups.
  • The potential harms equal or exceed the potential benefits of exercise or resting ECG screening in asymptomatic adults at low risk for CHD events.
  • CHD is defined as coronary artery disease and ischemic heart disease.
  • The patient population includes men and women without heart disease symptoms and without a diagnosis of cardiovascular disease.
  • Risk factors for CHD risk include older age, male sex, high blood pressure, smoking, abnormal lipid levels, diabetes, obesity, and sedentary lifestyle.
  • CHD risk is determined by a 10-year risk for a CHD event: low risk (< 10%), intermediate risk (10% – 20%), and high risk (> 20%).
  • Exercise ECG is more sensitive than resting ECG in the detection of coronary artery stenosis.
  • Exercise and resting ECGs have similar sensitivities in the prediction of CHD events.
  • Resting ECG abnormalities linked with future CHD events are ST-segment and T-wave abnormalities, left ventricular hypertrophy, left axis deviation, and bundle branch block (pooled hazard ratios, 1.5 – 1.9).
  • Exercise ECG abnormalities linked with future CHD events are ST-segment depression with exercise, failure to reach 85% or 90% of the maximal predicted heart rate, and abnormal heart rate recovery after exercise (pooled hazard ratios, 1.4 – 2.1).
  • Baseline ECG is not recommended for asymptomatic low-risk adults and is of unknown usefulness in adults at increased risk.
  • The usual treatment of asymptomatic adults at increased risk for CHD does not depend on ECG findings: diet and exercise modification, lipid-lowering medication, aspirin, hypertension management, and tobacco cessation.
  • The greatest potential benefit from ECG screening is for intermediate-risk adults who might be accurately reclassified to high risk.
  • 71% of asymptomatic adults with abnormal exercise treadmill ECG results had no coronary artery stenosis on angiography.
  • The risk for a serious adverse event related to an exercise ECG is approximately 1 in 10,000 tests.
  • Rates of angiography after abnormal exercise ECG results have been reported as 0.6% to 2.9%.
  • The risk for a serious adverse event from angiography is approximately 1.7%: death, 0.1%; myocardial infarction, 0.05%; stroke, 0.07%; and arrhythmia, 0.4%.
  • Rates of revascularization after abnormal exercise ECG test results have been reported as 0.1% and 0.5%.
  • Harms of resting ECG have not been reported in recent studies.

CLINICAL IMPLICATIONS

  • For asymptomatic adults at low risk for CHD events, the USPSTF recommends against screening with resting or exercise ECG for the prediction of such events.
  • For asymptomatic adults at intermediate or high risk for CHD events, the USPSTF finds insufficient evidence to assess the balance of benefits and harms of screening with resting or exercise ECG for the prediction of such events.