Cardiac Screening with Electrocardiography, Stress Echocardiography, or Myocardial Perfusion Imaging

Transcription

1 Cardiac Screening with Electrocardiography, Stress Echocardiography, or Myocardial Perfusion Imaging A D V I C E F O R H I G H V A L U E C A R E F R O M T H E A M E R I C A N C O L L E G E O F P H Y S I C I A N S

2 Background Info. Cardiovascular disease causes 1 in 3 deaths in the U.S. or about 800,000 deaths per year Direct and indirect costs of coronary heart disease (CHD) in 2009 were estimated at $195 billion More than half of those who die suddenly of CHD have no antecedent symptoms

3 Screening Patients A good screening test aims to identify the condition in asymptomatic patients before it manifests clinically Often, inappropriate cardiac testing is done in low risk adults Low risk in this population defined as those with an estimated 10 year risk for CHD events of < 10% Want to use the most appropriate test for the patient s risk level

4 Evidence Based Recommendations for the Use of Cardiac Testing in Asymptomatic Adults The USPSTF advises - screen low risk adults with rest or exercise EKG The American College of Cardiology does not recommend cardiac screening in low risk adults In studies looking at low risk patients with resting EKG abnormalities, this did not move the patient from being in a low risk category to a high risk one little effect on clinical decisions

5 Low Risk Population The ACC and the AHA recommend against stress echo or MPI for cardiovascular risk assessment in low risk, asymptomatic adults One reason cardiac screening in this population is ineffective is that for many abnormalities found there is not proven, effective treatment (i.e. LVH) Controlling risk factors i.e. smoking, obesity, DM, HTN, etc. is indicated regardless of testing

6 Harms of Screening Pharmacologic agents to induce stress can cause myocardial ischemia, arrhythmia, hypotension, and bronchospasm Myocardial perfusion imaging results in radiation exposure from using radionuclide tracers False positives up to ¾ of asymptomatic men with exercise induced ST segment depression on EKG have no significant angiographic CAD Angiography is associated with a risk of ~1.7% for serious adverse events death, MI, stroke, and arrhythmia

7 Overuse of Cardiac Testing in Asymptomatic Adults Underestimation of harms associated with screening May overestimate the benefit of revascularization on the basis of trials that used outdated medical treatment regimens Possible thought that negative screening results reassures the patient Financial incentives i.e. greater increases in reimbursement for MPI s among cardiologists Patient satisfaction linked to financial incentives

8 How to Reduce Overuse of Cardiac Testing Many risk calculators available, Framingham risk calculator most validated Regardless of risk calculator, in patients in the low risk category, screening is not indicated and focus should be on treating modifiable risk factors i.e. smoking, diabetes, HTN, and HLD Recommendations in higher risk pts not as clear cut USPSTF found insufficient evidence to determine whether benefits of screening ECG outweigh harms

9 Risk Calculators (10 year risk of a CV event) Calculator Risk factors included Website Framingham risk score SCORE PROCAM Reynolds risk score Age, sex, total and HDL cholesterol, smoking, SBP, and anti-htnsive meds Age, sex, total and HDL cholesterol, smoking, and SBP Age, LDL and HDL, smoking status, SBP, family history, DM II, triglyceride levels Age, HgbA1C, smoking, SBP, total and HDL, hscrp, and parental history of MI < 60 ulator.asp ome.aspx

10 AHA and ACC Recommendations Recommend MPI as a potential option for CV risk assessment in high risk pts Evidence on effects of cardiac screening on clinical outcomes in higher risk pts is sparse and does not clearly show clinical benefit

11 Disease Audience Target Population Interventions Outcomes Benefits of Screening Harms of Screening High value care advice High Value Care Recommendations Cardiovascular disease Internists, family physicians, other clinicians Asymptomatic adults with low probability of cardiovascular disease EKG (resting or stress), stress echo, MPI Mortality (all cause and disease specific), cardiovascular events (MI, CHF, arrhythmia, SCD) Identification of undiagnosed CHD, identification of those at risk for cardiovascular events Stress test: sudden death, adverse effect of pharmacologic event, MPI: radiation, False Positives: anxiety, additional tests Clinicians should not screen for cardiac disease in asymptomatic, low risk adults with resting or stress EKG, stress echo, or stress MPI Clinical considerations Cardiovascular risk assessment in asymptomatic adults should start with a risk calculator, adhere to recommendations, treat modifiable risk factors and encourage exercise

12 Reference Annals of Internal Medicine Volume 162, No. 6 March 2015