Hemodynamic Assessment of Valvular Stenosis and Regurgitation

One of the most controversial and challenging surgical undertakings of the next century promises to be foetal cardiac surgery. Animal studies have been underway for several years to gain an understanding of the physiological mechanisms required to achieve this undertaking. Not since the days of crosscirculation has there been a maternal risk associated with open-heart surgery. The diagnosis of congenital heart defects with foetal ultrasound can now be made as early as 12 weeks gestation. Simple cardiac abnormalities, such as valvular stenosis or atresia, alter intracardiac flow patterns and affect normal cardiac chamber development. Without early intervention, these complex lesions often require major surgical reconstruction, beginning in the neonatal period. Foetal cardiac bypass techniques have evolved from the use of roller pumps and bubble oxygenators primed with maternal blood to the use of an axial flow pump incorporated in a right atrial to pulmonary artery or aortic shunt. Because the blood entering the right atrium is oxygenated by the placenta, an oxygenator in the bypass circuit is probably not needed. The low prime axial flow pump system avoids the dilution of the foetus with the maternal adult haemoglobin and improves the outcome. A major focus of research has concentrated on maintenance of placental blood flow with the use of vasodilators and cyclooxygenase inhibitors. Investigation with primates will be necessary to confirm the placental physiology before human operations can be performed. As the foetal bypass challenges are overcome, there is the potential for a reduction in the number of complex cardiac lesions requiring early surgical intervention in the twenty-first century.

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INVASIVE AND NONINVASIVE HEMODYNAMIC ASSESSMENT IN ADULTS WITH FONTAN PALLIATION

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(18)31106-9 ◽

2018 ◽

Vol 71 (11) ◽

pp. A565

Author(s):

Alexander C. Egbe ◽

Mohamad Al-Otaibi ◽

Arooj Razzaq Khan

Keyword(s):

Hemodynamic Assessment ◽

Fontan Palliation

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The Laterality of the Carotid Murmur in Aortic Valvular Stenosis

Acta Medica Scandinavica ◽

10.1111/j.0954-6820.1963.tb16543.x ◽

2009 ◽

Vol 174 (6) ◽

pp. 751-752

Author(s):

E. Ask-Upmark ◽

I. Cullhed

Keyword(s):

Aortic Valvular Stenosis ◽

Valvular Stenosis

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Abstract 104: Serum from Patients with Aortic Valvular Stenosis Shows Decreased Cholesterol Efflux Capacities Despite Similar High-Density Lipoprotein Cholesterol Levels

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.32.suppl_1.a104 ◽

2012 ◽

Vol 32 (suppl_1) ◽

Author(s):

Benoit J Arsenault ◽

Mathieu R Brodeur ◽

David Rhainds ◽

Anne-Elen Kernaleguen ◽

Véronique Lavoie ◽

...

Keyword(s):

Cholesterol Efflux ◽

Pearson Correlation ◽

Hdl Cholesterol ◽

P Value ◽

Aortic Valvular Stenosis ◽

Cholesterol Efflux Capacity ◽

Cholesterol Levels ◽

Apolipoprotein A ◽

Valvular Stenosis ◽

Jet Velocity

Background: Studies have shown that low HDL-cholesterol levels may be associated with the progression of aortic valvular calcium and aortic valvular stenosis (AVS), but whether patients with AVS have impaired cholesterol efflux capacities is unknown. Methods and results: We have measured four parameters of cholesterol efflux capacity in apolipoprotein B-depleted serum samples from 48 patients with (aortic jet velocity ≥2.5 m/s, mean age = 72 ± 7 years and 72.7% men) and 51 patients without AVS (aortic jet velocity ≤ 1.7 m/s, mean age 71 ± 7 years and 70.6% men). Cholesterol efflux capacity was measured using J774 macrophages with and without stimulation of ABCA1 expression by cAMP (non-stimulated efflux, total efflux and ABCA1-mediated efflux), and HepG2 hepatocytes to measure SR-BI-mediated efflux. Mean HDL-cholesterol and apolipoprotein A-I levels as well as efflux are shown in the table for patients with vs. without AVS. The Pearson correlation coefficient between HDL-cholesterol levels and SR-B1-dependent efflux was 0.39 (p=0.007) in patients with AVS and 0.68 (<0.0001) in controls (P-value for the difference between the correlation coefficients obtained with Fisher’s test = 0.04). Conclusions: This study provides evidence that serum from patients with AVS may have impaired cholesterol efflux capacities, especially through the SR-B1 pathway. Table. Mean HDL-cholesterol and apolipoprotein A-I levels as well as non-stimulated-, total-, ABCA1-, and SR-B1-dependent cholesterol efflux obtained from patients’ serum with vs. without AVS. Data is shown as mean ± SD. Differences between categories were assessed using a Student unpaired t-test.

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