title: Beat-by-beat aortic valve area measurements indicate constant orifice area in aortic stenosis: analysis of Doppler data with varying RR intervals.
abstract: Gorlin formula calculation of aortic valve area suggests that orifice area increases in patients with aortic stenosis with rising cardiac output. Evidence that aortic orifice area varies was sought in patients with aortic stenosis by analyzing Doppler data beat by beat versus RR interval in 22 patients with spontaneous RR variability. Stroke volume increased in all patients from minimum to maximum RR interval by 129% +/- 19%. Over the same range of RR intervals, assessment of aortic valve area by (A) simultaneous inner and outer continuous wave Doppler signals, or (B) nonsimultaneous RR-matched pulsed wave Doppler from the left ventricular outflow tract and continuous wave Doppler from the aortic valve failed to suggest an increase in aortic valve area. A positive relationship between aortic valve area and RR interval was not consistently observed with the exception of seven out of eight patients with mild to moderate (pulsed wave Doppler/continuous wave Doppler time velocity integral ratio of 0.3 to 0.7) aortic stenosis (p less than 0.05). Beat-by-beat measurements of aortic valve orifice area using Doppler techniques do not suggest that the aortic stenosis orifice varies over a wide range of RR intervals and stroke volumes.
authors.affiliation: Department of Medicine, Mayo Clinic Jacksonville, FL 32224.
authors.forename: J L
authors.initials: JL
authors.lastname: Blackshear
authors.forename: E J
authors.initials: EJ
authors.lastname: Kapples
authors.forename: G E
authors.initials: GE
authors.lastname: Lane
authors.forename: R E
authors.initials: RE
authors.lastname: Safford
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000473:pathology; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D002302:Cardiac Output; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume