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Introduction Severe aortic stenosis (AS) poses an increased anesthetic risk for noncardiac surgery [1]. Although an echocardiogram provides a definitive diagnosis of AS, clinical findings are important as clues for [...], Purpose A pulsus parvus et tardus of the carotid artery, i.e., a small weak pulse with a delayed systolic peak, is a well-recognized clinical finding of aortic stenosis (AS). However, the diagnostic value of radial arterial pressure curves has not been specifically investigated. In this study, we investigated whether the radial arterial curves of patients with AS had distinguishable characteristics. Methods We studied 17 AS patients (valve area less than 0.8 [cm.sup.2]) and 17 control patients. The durations for the following intervals were measured, from the ECG-R to the beginning of the arterial pressure wave upstroke ([PTT.sub.Up]), from the ECG-R to the peak of the arterial pressure ([PTT.sub.peak]), and the difference between [PTT.sub.peak] and [PTT.sub.Up] ([T.sub.Upstroke]). Results The radial arterial pulse pressures did not differ significantly, indicating absence of a pulsus paruvus in the radial pressure of the AS patients. The [PTT.sub.Up] and [PTT.sub.peak] in the AS patients were 134 ± 18 and 337 ± 44 ms, respectively, while these values in the control patients were 143 ± 21 and 286 ± 64 ms. As a result of the differences in [PTT.sub.Up] and [PTT.sub.peak], the [T.sub.Upstroke] in the AS patients was greater than that in the control patients. The [T.sub.Upstroke] cutoff point that gave the maximal sensitivity (0.93) and specificity (0.65) was 156 ms. Conclusion Our study using the radial arterial curve validated a pulsus tardus as a diagnostic sign for severe AS, while the validity of a pulsus parvus as a diagnostic sign was not confirmed. Keywords Aortic stenosis * Pulse contour * Arterial pressure transit time * Monitoring

Epidermal growth factor receptor (EGFR) signaling contributes to aortic valve development in mice. Because developmental phenotypes in Egfr-null mice are dependent on genetic background, the hypomorphic [Egfr.sup.wa2] allele was made congenic on C57BL/6J (B6) and 129S1/SvImJ (129) backgrounds and used to identify the underlying cellular cause of EGFR-related aortic valve abnormalities. [Egfr.sup.wa2/wa2] mice on both genetic backgrounds develop aortic valve hyperplasia. Many B6-[Egfr.sup.wa2/wa2] mice die before weaning, and those surviving to 3 mo of age or older develop severe left ventricular hypertrophy and heart failure. The cardiac phenotype was accompanied by significantly thicker aortic cusps and larger transvalvular gradients in B6-[Egfr.sup.wa2/wa2] mice compared with heterozygous controls and age-matched [Egfr.sup.wa2] homozygous mice on either 129 or B6129F1 backgrounds. Histological analysis revealed cellular changes in B6-[Egfr.sup.wa2/wa2] aortic valves underlying elevated pressure gradients and progression to heart failure, including increased cellular proliferation, ectopic cartilage formation, extensive calcification, and inflammatory infiltrate, mimicking changes seen in human calcific aortic stenosis. Despite having congenitally enlarged valves, 129 and B6129F1-[Egfr.sup.wa2/wa2] mice have normal lifespans, absence of left ventricular hypertrophy, and normal systolic function. These results show the requirement of EGFR activity for normal valvulogenesis and demonstrate that dominantly acting genetic modifiers curtail pathological changes in congenitally deformed valves. These studies provide a novel model of aortic sclerosis and stenosis and suggest that long-term inhibition of EGFR signaling for cancer therapy may have unexpected consequences on aortic valves in susceptible individuals. epidermal growth factor receptor aortic sclerosis; hypertrophy; aortic stenosis; valvulogenesis

A study was conducted to examine whether young adults with bicuspid aortic valves were more likely to suffer from cardiac outcomes. Results concluded that there was no direct relationship between mortality among young adults with bicuspid aortic valves.

Abstract. Supravalvular aortic stenosis is an uncommon but well-characterized congenital form of left ventricular outflow obstruction. The lesion involves the ascending aorta and often occurs in association with pulmonary arterial [...]

Byline: R. E. Villavicencio (1), T. J. Forbes (1), R. L. Thomas (2), R. A. Humes (1) Keywords: Pressure recovery; Aortic valve stenosis; Pediatrics Abstract: This study was designed to evaluate the phenomenon of pressure recovery in pediatric patients with aortic stenosis and also to evaluate how observed differences between catheter and Doppler gradients can be predicted by Doppler echocardiography. Doppler measurements of aortic valve stenosis gradients are known to overestimate observed gradients in the catheterization laboratory. Pressure recovery has been shown to be a contributing factor to this discrepancy. However, the clinical relevance of correcting Doppler gradients using the pressure recovery equation has not been evaluated in the pediatric population. Simultaneously obtained catheter and Doppler gradients were studied in 14 patients (range, 0.03--18 years mean, 4.1 years) with aortic valve stenosis. A total of 23 data points were measured because 9 patients underwent balloon valvuloplasty and had both a pre- and a post-balloon valvuloplasty data point in the study. The catheter gradients were then compared to peak, mean, and pressure recovery corrected Doppler gradients. Pressure recovery was calculated using a previously validated equation. As expected, measured echocardiographic continuous-wave peak Doppler gradients overestimated the observed catheter gradients (range, 16--93 mmHg mean, 43 mmHg). The continuous-wave peak Doppler gradients, mean, and pressure recovery adjusted gradients were equally as good in correlating the observed catheter gradients to those obtained by Doppler echocardiography (r = 0.92). However, pressure recovery corrected Doppler gradients were in better agreement with catheter gradients than echocardiographic mean or peak Doppler gradients (95% limit of agreement: -9 to 19 mmHg for pressure recovery corrected gradients, -30 to 11 mmHg for mean Doppler gradients, and 2--83 mmHg for peak Doppler gradients). Measured continuous-wave peak Doppler gradients consistently overestimated catheter gradients. The noted differences may be predicted using the pressure recovery equation. Pressure recovery is a significant factor in children with aortic valve stenosis. Author Affiliation: (1) Department of Pediatrics, Division of Cardiology, Wayne State University School of Medicine/Detroit Medical Center and Children's Hospital of Michigan, 3901 Beaubien Avenue, Detroit, MI 48201, USA (2) Department of Pediatrics, Children's Research Center of Michigan, Detroit, MI 48201, USA Article History: Registration Date: 01/01/2002 Online Date: 30/04/2003

Byline: F.M. McCaffrey (1), F.S. Sherman (1) Keywords: Key words: Fetus -- Heart disease (congenital) -- Aortic stenosis Abstract: We sought to identify echocardiographic markers that might be useful for managing fetuses with significant aortic stenosis. The study was a retrospective review of fetal echocardiographic studies and postnatal outcomes of all fetuses diagnosed with significant aortic stenosis who did not have a hypoplastic left ventricle on the initial echocardiogram. Where possible, fetal echocardiographic measurements included the aortic, mitral, pulmonary, and tricuspid valve annulus sizes left ventricular dimensions and volume septal and left ventricular wall thicknesses and echocardiographic Doppler interrogation of the left heart and oval fossa. Observations also included an assessment of ascites, pericardial effusion, and endocardial fibroelastosis. Prenatal measurements were compared to postnatal outcomes. Four patients (group 1) had either clinically successful relief of their aortic obstruction (n= 3) or required no intervention (n= 1). Five fetuses evolved to the hypoplastic left heart syndrome (group 2). These infants demonstrated little or no growth in left ventricular, aortic valve, or mitral valve dimensions on serial examination. They also more often exhibited mitral stenosis, severe restriction of interatrial shunting, and early to mid second trimester left ventricular dilatation. Serial measurements of fetal cardiac size and function are helpful for predicting the postnatal outcome of fetuses with aortic stenosis. Author Affiliation: (1) Division of Pediatric Cardiology, University of Kentucky Medical Center, Room MN 472, 800 Rose Street, Lexington, KY 40536-0084, USA, US

A study was conducted on 41 patients over two periods, each six months long to evaluate the reliability of echocardiographic diagnosis in comparison with clinical diagnosis. Both types of diagnosis had a 75% agreement in most cases although clinical diagnosis for aortic stenosis was unsatisfactory in the first period. Symptoms of aortic stenosis may be undetected until the critical stage of the disease. Echocardiography may facilitate the discovery of aortic stenosis and other heart diseases thereby enhancing clinical diagnosis to prevent fatal outcomes in elderly patients.

In aortic valve stenosis (AS), heart murmurs arise as an effect of turbulent blood flow distal to the obstructed valves. With increasing AS severity, the flow becomes more unstable, and the ensuing murmur becomes more complex. We hypothesize that these hemodynamic flow changes can be quantified based on the complexity of the phonocardiographic (PCG) signal. In this study, sample entropy (SampEn) was investigated as a measure of complexity using a dog model. Twenty-seven boxer dogs with various degrees of AS were examined with Doppler echocardiography, and the peak aortic flow velocity ([V.sub.max]) was used as a reference of AS severity. SampEn correlated to [V.sub.max] with R = 0.70 using logarithmic regression. In a separate analysis, significant differences were found between physiologic murmurs and murmurs caused by AS (p < 0.05), and the area under a receiver operating characteristic curve was calculated to 0.96. Comparison with previously presented PCG measures for AS assessment showed improved performance when using SampEn, especially for differentiation between physiological murmurs and murmurs caused by mild AS. Studies in patients will be needed to properly assess the technique in humans. Index Terms--Aortic stenosis (AS), bioacoustics, heart sound, murmur, sample entropy (SampEn).