SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Aortic valve

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Left-sided congenital heart disease (CHD) encompasses a spectrum of malformations that range from bicuspid aortic valve to hypoplastic left heart syndrome. It contributes significantly to infant mortality and has serious implications in adult cardiology. Although left-sided CHD is known to be highly heritable, the underlying genetic determinants are largely unidentified. In this study, we sought to determine the impact of structural genomic variation on left-sided CHD and compared multiplex families (464 individuals with 174 affecteds (37.5%) in 59 multiplex families and 8 trios) to 1,582 well-phenotyped controls. 73 unique inherited or de novo CNVs in 54 individuals were identified in the left-sided CHD cohort. After stringent filtering, our gene inventory reveals 25 new candidates for LS-CHD pathogenesis, such as SMC1A, MFAP4, and CTHRC1, and overlaps with several known syndromic loci. Conservative estimation examining the overlap of the prioritized gene content with CNVs present only in affected individuals in our cohort implies a strong effect for unique CNVs in at least 10% of left-sided CHD cases. Enrichment testing of gene content in all identified CNVs showed a significant association with angiogenesis. In this first family-based CNV study of left-sided CHD, we found that both co-segregating and de novo events associate with disease in a complex fashion at structural genomic level. Often viewed as an anatomically circumscript disease, a subset of left-sided CHD may in fact reflect more general genetic perturbations of angiogenesis and/or vascular biology.

Concepts: Gene, Genetics, Copy number variation, Human genome, Biology, Heart, Aortic valve, Hypoplastic left heart syndrome

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OBJECTIVESThe Trifecta valve (St. Jude Medical) was introduced into clinical practice as a tri-leaflet stented pericardial valve designed for supra-annular placement in the aortic position. The present study aims to evaluate the preliminary results with this new bioprosthesis.METHODSSeventy patients underwent aortic valve replacement (AVR) with the Trifecta valve between August 2010 and December 2011. Thirty-three patients were male and 37 were female (52.9%). Mean age was 74.65 ± 7.63 (range 47-90 years). Prevalent cause of AVR was aortic stenosis in 64 (91.43%) patients. The mean preoperative pressure gradient was 50 ± 17 (range 20-84 mmHg), and the mean aortic valve area was 0.77 ± 0.33. Five (7.14%) patients were operated on due to aortic valve endocarditis. One patient was operated on due to isolated, severe aortic insufficiency. All patients were in New York Heart Association functional class III or IV. Twenty-eight (40%) patients underwent concomitant procedures.RESULTSConcomitant procedures were coronary artery bypass grafting (n = 25), mitral valve replacement (n = 1), ablation of atrial fibrillation (n = 1) and septal myomectomy (n = 1). There were no intraoperative deaths. The 30-day in-hospital mortality was 2.85% (2 of 70). One late death occurred during the in-hospital stay due to a multiorgan failure on postoperative day 60. There were 2 (2.85%) perioperative strokes. Mean pressure gradient decreased significantly from a preoperative value of 50 ± 17 mmHg to an intraoperative gradient of 9 ± 4 mmHg (Table 3). The mean gradients were 14, 11, 11, 8 and 6 mmHg for the 19, 21, 23, 25 and 27 mm valve size, respectively. No prosthesis dislocation, endocarditis, valve thrombosis or relevant aortic regurgitation was observed at discharge.CONCLUSIONSThe initial experience with the Trifecta valve bioprosthesis shows excellent outcomes with favourable early haemodynamics. Further studies with longer follow-up are needed to confirm those preliminary results.

Concepts: Cardiology, Heart, Mitral valve prolapse, Aortic valve, Valvular heart disease, Aortic valve stenosis, Aortic valve replacement, Aortic insufficiency

28

Reoperation for failing stentless aortic valve replacement is a technically demanding procedure that has traditionally been tackled in one of two ways: either root replacement or the more conservative option of implanting a stented valve within the valve. We sought to determine the relative operative risks, follow-up status and medium to long-term survival of these two methods.

Concepts: Derivative, Left ventricle, Aortic valve, Valve, Valve Corporation, Aortic valve replacement, Aortic insufficiency

28

We report a case with a very rare complication of transcatheter aortic valve implantation. Rupture of the NovaFlex balloon (Edwards transfemoral balloon catheter) occurred during the inflation of the Edwards SAPIEN valve, resulting in dissection of the right common and external iliac arteries during withdrawal of the balloon catheter. The NovaFlex balloon is a part of the Edwards NovaFlex XT transfemoral delivery system.

Concepts: Right-wing politics, External iliac artery, Aortic valve, Internal iliac artery, Arteries, Iliac artery, Iliac vein, X-Force

28

Valve-sparing aortic root reconstruction (VSRR) is an accepted method to treat patients with aortic root dilation. The role of the VSRR is less well defined for patients with bicuspid aortic valve, severe aortic valve insufficiency, congenital heart defects, and type A aortic dissection. We studied the clinical outcome of patients who underwent VSRR for expanded indications.

Concepts: Aortic aneurysm, Aortic dissection, Aorta, Congenital heart defect, Congenital heart disease, Aortic valve, Aortic insufficiency, Bicuspid aortic valve

28

OBJECTIVE: A supra-annular aortic valve prosthesis is often used for aortic valve replacement in patients with a small aortic annulus. However, which suture technique provides the best valve performance has not been studied. We aimed to compare valve performance between 2 different suture techniques. METHODS: We reviewed 152 patients undergoing aortic valve replacement with a 19- or 21-mm Carpentier-Edwards Perimount Magna aortic bioprosthesis (Edwards Lifesciences, Irvine, Calif) between June 2008 and December 2010. Simple interrupted sutures were used in 102 patients (group A, 19-mm prosthesis in 47 patients and 21-mm prosthesis in 55 patients), and noneverting mattress sutures were used in 50 patients (group B, 19-mm prosthesis in 20 patients and 21-mm prosthesis in 30 patients). Transthoracic echocardiograms were performed at baseline and before discharge in all patients and 1 year after surgery in 141 patients. We compared the effective orifice area and incidence of prosthesis-patient mismatch (effective orifice area index <0.85 cm(2)/m(2)) between 2 groups. RESULTS: The mean postoperative effective orifice areas were 1.41 ± 0.32 cm(2)/m(2) in group A and 1.30 ± 0.28 cm(2)/m(2) in group B (P = .025). The incidence of prosthesis-patient mismatch was 29% in group A and 56% in group B (P = .002). A multivariate analysis has shown that simple interrupted suturing is a negative predictor of prosthesis-patient mismatch (odds ratio, 0.33; 95% confidence interval, 0.13-0.83; P = .018). At 1 year, the incidence of prosthesis-patient mismatch was 27% in group A and 47% in group B (P = .023). CONCLUSIONS: Simple interrupted sutures provide larger effective orifice areas and reduce the incidence of prosthesis-patient mismatch after aortic valve replacement with a small supra-annular bioprosthesis. This suture technique is preferred in those patients to maximize valve performance.

Concepts: Surgical suture, Aortic valve, Simple interrupted stitch

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To evaluate factors associated with aortic enlargement in patients with a bicuspid aortic valve (BAV) and the impact of isolated aortic valve replacement (AVR).

Concepts: Aortic aneurysm, Aortic valve, Aortic valve replacement, Aortic insufficiency, Bicuspid aortic valve

28

OBJECTIVE: Calcific aortic valve disease (CAVD) is a major public health problem with no effective treatment available other than surgery. We previously showed that mature heart valves calcify in response to retinoic acid (RA) treatment through downregulation of the SRY transcription factor Sox9. In this study, we investigated the effects of excess vitamin A and its metabolite RA on heart valve structure and function in vivo and examined the molecular mechanisms of RA signaling during the calcification process in vitro. METHODS AND RESULTS: Using a combination of approaches, we defined calcific aortic valve disease pathogenesis in mice fed 200 IU/g and 20 IU/g of retinyl palmitate for 12 months at molecular, cellular, and functional levels. We show that mice fed excess vitamin A develop aortic valve stenosis and leaflet calcification associated with increased expression of osteogenic genes and decreased expression of cartilaginous markers. Using a pharmacological approach, we show that RA-mediated Sox9 repression and calcification is regulated by classical RA signaling and requires both RA and retinoid X receptors. CONCLUSIONS: Our studies demonstrate that excess vitamin A dietary intake promotes heart valve calcification in vivo. Therefore suggesting that hypervitaminosis A could serve as a new risk factor of calcific aortic valve disease in the human population.

Concepts: Gene, In vitro, Aortic valve, Retinol, Vitamin A, Valvular heart disease, Valves, Aortic valve stenosis

28

About 1-2% of the babies are born with bicuspid aortic valves instead of the normal aortic valve with three leaflets. A significant portion of the patients with the congenital bicuspid valve morphology suffer from aortic valve stenosis and/or ascending aortic dilatation and dissection thus requiring surgical intervention when they are young adults. Patients with bicuspid aortic valves (BAVs) have also been found to develop valvular stenosis earlier than those with the normal aortic valve. This paper overviews current knowledge of BAVs, where several studies have suggested that the mechanical stresses induced on the valve leaflets and the abnormal flow development in the ascending aorta may be an important factor in the diseases of the valve and the aortic root. The long-term goals of the studies being performed in our laboratory are aimed towards potential stratification of bicuspid valve patients who may be at risk for developing these pathologies based on analyzing the hemodynamic environment of these valves using fluid-structure interaction (FSI) modeling. Patient-specific geometry of the normal tri-cuspid and bicuspid valves are reconstructed from real-time 3D ultrasound images and the dynamic analyses performed in order to determine the potential effects of mechanical stresses on the valve leaflet and aortic root pathology. This paper describes the details of the computational tools and discusses challenges with patient-specific modeling.

Concepts: Aortic dissection, Aorta, Ascending aorta, Left ventricle, Aortic valve, Aortic valve stenosis, Aortic insufficiency, Bicuspid aortic valve

28

Girls and women with Turner syndrome are at risk for aortic dissection and rupture. However, the size of the aorta and the clinical characteristics among those with Turner syndrome and dissection have received little attention.

Concepts: Aortic aneurysm, Aortic dissection, Aorta, Marfan syndrome, Left ventricle, Aortic valve, Bicuspid aortic valve, Traumatic aortic rupture