Does computer-based edge enhancement alter the interpretation of digital coronary arteriograms?

82A

J!KCVol. 15, Mo.2 February 1990:82A

ABSTRACTS

FACTORSAFFECTINGTHE INCREASEDACCURACY OF HEART RATE ADJDSTED ST DEPRESSIONSFOR

PREDICTINGTRIPLE VESSEL - LEFT MAIN DISEASE. Marco Bobbio, M.D., Robert Detrano, M.D., Ph.D.,Andras Janosi, M.D., Albert0 Righetti, M.D. -MatthiasPfisterer,M.D., Walter Steiubrunn,M.D., Kern H. Guppy, M.D., Jaap S&aid, D.E.. W. Deckers, M.D., Johann-Jakob 5

Long Beach Veterans Administration Center, Long Beach, CA.

Medical

We have previouslyreportedthat the increasedaccuracy of heart rate adjustedST depressions(ST/RR)cannot be confirmed in all laboratories. which clinical

In order and exercise

to determine

factors affect this increasedaccuracy,we examined both the exercise induced ST depression (ST) and ST/HR in 2180 angiographicreferrals (350 with triple vessel - left main disease) in eight participatinglaboratories. 1he sensitivities(SE) of ST and ST/RR at a specificityof 63.78 correspondingto 1 mm ST depressionwere 73% and 75% respectively. Stepwiselinear regressionwas done to determinewhich factors affectedthe improved SE of ST/Ii& Those factorswere treadmill versus bicycle exercise (~~04) and #exercise inducedheart rate increase (p<.OOO%). We concludethat the improvedaccuracy of ST/RR is small and that it increasesat higher exerciseheart rates.

EVIDENCE THAT ATRIAL REPOLARIZATION MAY BE A CAUSE OF FALSE POSITIVE EXERCISE TESTS ry Koch, Pb.D, Mary Beth Blauwet, B.& James ricerW. Hinds, UD, and Leonard S Gettes, veraity of North Carolina,Chapel Hill, NC Atrial repolarization(AREP)waves are opposite in direction to P waves, may bave a magnitudeof l-2 mm, and may extend into the ST segment and T wave. We postulated tbat exaggerated AREP waves during and after exercise could produce ST segment depression(STD)mimicing myocardial wave, PR segment and ST segment in

.Omin identified FP tests Our results suggest new sati useful ECG criteria for predictinga FP exercise test and supportthe hypothesis tbat exaggeratedAREP wavea may be a cau;c of FP testr