简介：BackgroundManypatientshavesymptomssuggestiveofcoronaryarterydisease(CAD)andareoftenevaluatedwiththeuseofdiagnostictesting,althoughtherearelimiteddatafromrandomizedtrialstoguidecare.MethodsWerandomlyassigned10,003symptomaticpatientstoastrategyofinitialanatomicaltestingwiththeuseofcoronarycomputedtomographicangiography(CTA)ortofunctionaltesting(exerciseelectrocardiography,nuclearstresstesting,orstressechocardiography).Thecompositeprimaryendpointwasdeath,myocardialinfarction,hospitalizationforunstableangina,ormajorproceduralcomplication.SecondaryendpointsincludedinvasivecardiaccatheterizationthatdidnotshowobstructiveCADandradiationexposure.ResultsThemeanageofthepatientswas60.8±8.3years,52.7%werewomen,and87.7%hadchestpainordyspneaonexertion.ThemeanpretestlikelihoodofobstructiveCADwas53.3±21.4%.Overamedianfollow-upperiodof25months,aprimaryend-pointeventoccurredin164of4996patientsintheCTAgroup(3.3%)andin151of5007(3.0%)inthefunctional-testinggroup(adjustedhazardratio,1.04;95%confidenceinterval,0.83to1.29;P=0.75).CTAwasassociatedwithfewercatheterizationsshowingnoobstructiveCADthanwasfunctionaltesting(3.4%vs.4.3%,P=0.02),althoughmorepatientsintheCTAgroupunderwentcatheterizationwithin90daysafterrandomization(12.2%vs.8.1%).ThemediancumulativeradiationexposureperpatientwaslowerintheCTAgroupthaninthefunctional-testinggroup(10.0mSvvs.11.3mSv),but32.6%ofthepatientsinthefunctional-testinggrouphadnoexposure,sotheoverallexposurewashigherintheCTAgroup(mean,12.0mSvvs.10.1mSv;P<0.001).ConclusionsInsymptomaticpatientswithsuspectedCADwhorequirednoninvasivetesting,astrategyofinitialCTA,ascomparedwithfunctionaltesting,didnotimproveclinicaloutcomesoveramedianfollow-upof2years.