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Quantification of aortic regurgitation utilizing continuous wave Doppler ultrasound halftime
152‘4
jACC Vol. 15, No. 2 February 1990:152A
ABSTRACTS
INHERITED VENTRICULAREmPY AND SUDDEN YOUNGGERMANSHEPHERD DOGS F. GilmourJr., PhD, FACC, !b& StateCollegeof Veten-
threshold 1ncr&ses pressure KSP). To primary VF of acute anesthetized dogs u ing, including CS c
We have identifi spontaneous structure an QT intervals.
effect in ~sc~ern~a extracellular flu!
envl ronment.
characteristics of theect dogs wen similar,theunderlying substrateforSD aDDears ed. In addition.SD was associated withtheonset of ktricul~ ectopy.Furtherstudiesof this new of inheritedSD mayidentifymechanismsfor thedevelopmentof QU~TIFI~TI~N OF AORTIC~GURGITATIONUTILIZING CONTINUOUS WAVE DOPPLERULTRASOUND HALFTIME ??
shaano~
..
Va~dcrbilt
ventricular couplets and tachycardia were also elicited. The probabilityof a stretch-inducedarrhythmia(SIA) was determined from multiple alternating sequences in which a stretch of amplitude(Av) or no stretchwas delivered. As AV increased,the
exceeded,and approached 1.0 at physiologic volume. With V, = 20 ml (end-
TeagueMD FACC, and Wyatt F. VoylesMD FACC. Universityof Oklahomaand VA Centers,OklahomaCity, OK. rt our 5 year experience withthe continuous wave we r Doppler halftime(DHT) method for the quantification of aortic regurgitation (AI). Of 975 AI patientsso studied, 161 underwent cardiaccatheterization within16~23daysfor the determinationof regurgitant fraction (RF) and angiographic AI grade (angio). DHT inverselycorrelated with RF in 68 studiesfree of significant(>2+) mitral regurgitation (Y=-. 0101X +.84, r=.84, SEE=.ll)where RF rangedfrom 9 to 71%. We evaluatedDHT-400msec.,derived in the first80 studies,as a thresholdfor separationof mild (l-2+, N=lOS) AI from significant (3-4+, N=S6) angio AI. Prospective sensitivity was lOO%, while specificity was 75%. Of the 26 false positives with DHT<400msec. and mild angio AI, left ventricularend diastolicpressures exceeded 20 rmnHgin 15, and aortic stiffness was greater than 1.2 mmHg/ccin 4 (+l s.d. ve groupmean). Aortic or mitral stenosisin 30 end 9 patients respectively,.aia not influence either RF or Angio correlates with DHT. We conclude that the Doppler halftime technique correlates well with invasive regurgitant fraction, and that DHT < 400
stretchpredictablyinitiates arrhythmiasand susceptibilityto SIAs is enhancedby increasedpreload. Thus,in cardiovasculardisorders iated with regional dyskinesisor global dilatation, verltricular ectopy may arise, in part, by a mechanismof myocardialstretch.
msec. accuratelyidentifiespatients with significant aortic regurgitationand/or high left ventricularend diastolicprsssure,both of which may warrant further evaluationand treatment.
jACC Vol. 15, No. 2 February 1990:152A
ABSTRACTS
INHERITED VENTRICULAREmPY AND SUDDEN YOUNGGERMANSHEPHERD DOGS F. GilmourJr., PhD, FACC, !b& StateCollegeof Veten-
threshold 1ncr&ses pressure KSP). To primary VF of acute anesthetized dogs u ing, including CS c
We have identifi spontaneous structure an QT intervals.
effect in ~sc~ern~a extracellular flu!
envl ronment.
characteristics of theect dogs wen similar,theunderlying substrateforSD aDDears ed. In addition.SD was associated withtheonset of ktricul~ ectopy.Furtherstudiesof this new of inheritedSD mayidentifymechanismsfor thedevelopmentof QU~TIFI~TI~N OF AORTIC~GURGITATIONUTILIZING CONTINUOUS WAVE DOPPLERULTRASOUND HALFTIME ??
shaano~
..
Va~dcrbilt
ventricular couplets and tachycardia were also elicited. The probabilityof a stretch-inducedarrhythmia(SIA) was determined from multiple alternating sequences in which a stretch of amplitude(Av) or no stretchwas delivered. As AV increased,the
exceeded,and approached 1.0 at physiologic volume. With V, = 20 ml (end-
TeagueMD FACC, and Wyatt F. VoylesMD FACC. Universityof Oklahomaand VA Centers,OklahomaCity, OK. rt our 5 year experience withthe continuous wave we r Doppler halftime(DHT) method for the quantification of aortic regurgitation (AI). Of 975 AI patientsso studied, 161 underwent cardiaccatheterization within16~23daysfor the determinationof regurgitant fraction (RF) and angiographic AI grade (angio). DHT inverselycorrelated with RF in 68 studiesfree of significant(>2+) mitral regurgitation (Y=-. 0101X +.84, r=.84, SEE=.ll)where RF rangedfrom 9 to 71%. We evaluatedDHT-400msec.,derived in the first80 studies,as a thresholdfor separationof mild (l-2+, N=lOS) AI from significant (3-4+, N=S6) angio AI. Prospective sensitivity was lOO%, while specificity was 75%. Of the 26 false positives with DHT<400msec. and mild angio AI, left ventricularend diastolicpressures exceeded 20 rmnHgin 15, and aortic stiffness was greater than 1.2 mmHg/ccin 4 (+l s.d. ve groupmean). Aortic or mitral stenosisin 30 end 9 patients respectively,.aia not influence either RF or Angio correlates with DHT. We conclude that the Doppler halftime technique correlates well with invasive regurgitant fraction, and that DHT < 400
stretchpredictablyinitiates arrhythmiasand susceptibilityto SIAs is enhancedby increasedpreload. Thus,in cardiovasculardisorders iated with regional dyskinesisor global dilatation, verltricular ectopy may arise, in part, by a mechanismof myocardialstretch.
msec. accuratelyidentifiespatients with significant aortic regurgitationand/or high left ventricularend diastolicprsssure,both of which may warrant further evaluationand treatment.