PubMed · 5820537
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K Chartikavanij. Aortic valve replacement.. https://pubmed.ncbi.nlm.nih.gov/5820537/
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The aim of the present study was to evaluate nonuniformity in pressure overload hypertrophy due to aortic stenosis. Twenty patients were included in the present analysis. Ten patients with severe aortic stenosis were studied preoperatively as well as early (21 +/- 8 months) and (89 +/- 21 months) after aortic valve replacement (AVR) using left ventricular biplane angiograms, high-fidelity pressure measurements and endomyocardial biopsies. Ten normal subjects served as controls. LV systolic function was assessed from biplane ejection fraction, and diastolic function from the time constant of relaxation, the peak filling rate and the constant of myocardial stiffness. Nonuniformity was evaluated from the coefficient of variation of the time to end-systole (systolic asynchrony) and peak filling rate (diastolic asynchrony) of 12 regions in right anterior oblique and left anterior oblique projection. Ejection fraction was comparable in patients with aortic stenosis and in controls, whereas preoperatively diastolic dysfunction with prolonged relaxation and increased stiffness was present in patients with aortic stenosis and was normalized late after AVR. LV systolic asynchrony was present (>25D of controls) in 7 and diastolic asynchrony in 10 of 10 patients with aortic stenosis. Early as well as late after AVR systolic asynchrony was normalized in 9 of 10 patients. Diastolic asynchrony was present early AVR in all but one patient, although there was a significant improvement with respect to the preoperative evaluation. Late after AVR there was a normalization of diastolic asynchrony in 9 of 10 patients with aortic stenosis. Thus, it is concluded that systolic asynchrony is normalized early after AVR probably due to its load-sensitivity, whereas diastolic asynchrony persists probably due to residual LV hypertrophy with increased interstitial fibrosis and myocardial stiffness. Late after AVR, diastolic asynchrony is normalized due to structural remodeling with regression of both myocardial hypertrophy and interstitial fibrosis.
To compare characteristics of aortic regurgitation (AR), the results of 213 procedures (110 balloon aortic valvotomies [BAV] and 103 surgical aortic valvotomies [SAV]) for treatment of congenital aortic valve stenosis were reviewed. These procedures were performed in 187 patients from June 1981 to September 1993. Echocardiograms recorded immediately before, within 6 months afterward, and at latest follow-up were compared. Color Doppler was used to assess the degree of AR and was quantified as the ratio of the regurgitant jet width to valve annulus, the jet width ratio. Whereas BAV patients were older (median age 5.7 years vs 3 months; p = 0.0001), there was no significant difference in median follow-up interval (3.1 years [range 0.5 to 7.2] for BAV vs 3.6 years [range 0.6 to 10.4] for SAV; p = 0.44). The mean balloon-to-annulus ratio for BAV was 0.99 +/- 0.09. An open valvotomy was performed in 83% of surgical cases. Acute systolic gradient reduction and subsequent increase at late follow-up was similar for both groups. Acutely, the mean jet width ratio increased similarly (p = 0.84) for BAV (+9 +/- 15%; p = 0.0001) and SAV (+9 +/- 12%; p = 0.0003) and was not related to age at procedure. At late follow-up, mean jet width ratio further increased significantly in both groups, although there was no difference (p = 0.17) in amount of progression (BAV +10 +/- 12%; p = 0.0001, SAV +15 +/- 13%; p = 0.0002). Thus, BAV and SAV produce AR of similar severity with similar rates of progression.
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