In Silico Shear and Intramural Stresses are Linked to Aortic Valve Morphology in Dilated Ascending Aorta.

OBJECTIVE/BACKGROUND: The development of ascending aortic dilatation in patients with bicuspid aortic valve (BAV) is highly variable, and this makes surgical decision strategies particularly challenging. The purpose of this study was to identify new predictors, other than the well established aortic size, that may help to stratify the risk of aortic dilatation in BAV patients. METHODS: Using fluid-structure interaction analysis, both haemodynamic and structural parameters exerted on the ascending aortic wall of patients with either BAV (n = 21) or tricuspid aortic valve (TAV; n = 13) with comparable age and aortic diameter (42.7 ± 5.3 mm for BAV and 45.4 ± 10.0 mm for TAV) were compared. BAV phenotypes were stratified according to the leaflet fusion pattern and aortic shape. RESULTS: Systolic wall shear stress (WSS) of BAV patients was higher than TAV patients at the sinotubular junction (6.8 ± 3.3 N/m2 for BAV and 3.9 ± 1.3 N/m2 for TAV; p = .006) and mid-ascending aorta (9.8 ± 3.3 N/m2 for BAV and 7.1 ± 2.3 N/m2 for TAV; p = .040). A statistically significant difference in BAV versus TAV was also observed for the intramural stress along the ascending aorta (e.g., 2.54 × 105 ± 0.32 × 105 N/m2 for BAV and 2.04 × 105 ± 0.34 × 105 N/m2 for TAV; p < .001) and pressure index (0.329 ± 0.107 for BAV and 0.223 ± 0.139 for TAV; p = .030). Differences in the BAV phenotypes (i.e., BAV type 1 vs. BAV type 2) and aortopathy (i.e., isolated tubular vs. aortic root dilatations) were associated with asymmetric WSS distributions in the right anterior aortic wall and right posterior aortic wall, respectively. CONCLUSION: These findings suggest that valve mediated haemodynamic and structural parameters may be used to identify which regions of aortic wall are at greater stress and enable the development of a personalised approach for the diagnosis and management of aortic dilatation beyond traditional guidelines.

David operation: single center 10-year experience.

AIM: Aortic valve-sparing operation has been progressively widely performed for the treatment of aortic root aneurysm. Nowadays, this procedure has been proposed even in presence of a bicuspid aortic valve, severe aortic regurgitation or in primary aortic dissection repair. We present our ten-year experience focusing on mid-term echocardiographic follow-up. METHODS: Between June 2002 and February 2012, 139 patients (mean age of 61±12 years) underwent aortic valve-sparing operation with valve reimplantation. Twenty-seven patients (19%) had bicuspid aortic valve; in eighteen cases (13%) cusp motion or anatomical abnormalities concurred in determining aortic regurgitation and needed an adjunct cusp repair. A Gelweave Valsalva™ graft was implanted in all the patients. RESULTS: The mortality pre-discharge was 0.7% (1 patient). The cumulative 1-year, 5-years and 8-years survival rates were 99%, 93% and 87% respectively. Postoperative aortic regurgitation more than mild degree (>2+/4+) was the only significant risk factors for redo aortic valve surgery Freedom from reoperation due to aortic valve regurgitation was 96% at 1 year, 90% at 5 years and 86% at 8 years. When comparing freedom from reoperation in patients with bicuspid vs tricuspid aortic valve, no differences were found (P=0.31) and the rate of aortic valve reoperation was significantly higher (P<0.001) in patients who received leaflet's repair. CONCLUSION: The durability of valve reimplantation was found to be excellent in patients with tricuspid aortic valve and normal or nearly normal cusps. Cusp prolapse and complication after cusp repair turned out to be the main causes for early failure.

Domino heart transplantation: long-term outcome of recipients and their living donors: single center experience.

BACKGROUND: "Domino" cardiac procedure is an effective option to increase the donor pool when heart-lung transplantation (HLT) is the only treatment for patients with terminal cardiopneumopathy. We reviewed the long-term outcomes of domino cardiac donors and recipients at our institution. METHODS: Ten of 35 patients who underwent HLT from 1991 onward served as domino cardiac donors. They included eight female and two male subjects of overall mean age of 33 years and mean weight of 55 kg. Their diagnoses were primary pulmonary hypertension (n = 6) as well as cystic fibrosis, bronchiectasis, Eisenmenger's syndrome, and bronchiolitis obliterans (n = 1 each). The domino cardiac recipients included six males and four females of overall mean age of 47 years and mean weight of 61 kg. They were affected by ischemic heart disease (n = 5), cardiomyopathy (n = 4), and valvular heart disease (n = 1). Mean pulmonary vascular resistance was 3 Wood units. The heart was used either in the orthotopic (n = 8) or in the heterotopic position (n = 2). RESULTS: The 1-, 5-, and 10-year survivals for the domino cardiac donors versus their recipients were 60%, 40%, 30% versus 90%, 70%, 60%, respectively. Five domino donors developed bronchiolitis obliterans syndrome. Among the domino recipients group, cardiac allograft vasculopathy was rare (n = 1). Common causes of late death were in the domino recipients infections in the domino donors (n = 2) and malignancies. CONCLUSIONS: Our experience suggested good long-term results of the domino procedure.