Morphological and Clinical Findings of Explanted Carpentier-Edwards Perimount Pericardial Valve in the Aortic Position.

BACKGROUND: Freedom from structural valve deterioration (SVD) at 15 years with the Carpentier-Edwards (CE) Perimount pericardial valve in the aortic position was 60% in patients aged <60 years compared to 90% and 99% in patients aged 60-70 years and >70 years, respectively. The study aim was to focus on the causes of SVD requiring valve explant according to three different age groups: <60 years, 60-70 years, and >70 years. The short- and longterm clinical results of the patient cohort, followed for 25 years, are presented. METHODS: A retrospective review was made of 89 patients among 2,405 who had undergone elective aortic valve replacement (AVR) with CE pericardial valves between November 1981 and March 2011, and in whom the prosthesis explant was secondary to degeneration of the valve. RESULTS: Patients aged >70 years experienced more late complications such as endocarditis (p = 0.02) and mortality (p = 0.02). Following surgery for prosthesis explant and replacement, 39 of the 89 patients (44%) died. The average time to postoperative mortality in that population was 2.8 ± 3.6 years. On combining all causes of SVD, earlier dysfunction was noted in patients aged >60 years, and late dysfunction in patients aged <60 years (p = 0.003). However, there was no significant difference between groups in the process of degeneration (either calcification, pannus, tear, thrombus, endocarditis) (p = NS). No predictors were found of early and late dysfunction. CONCLUSIONS: Patients aged >60 years in whom a CE Perimount valve was implanted in the aortic position were more prone to early degeneration of their valve and related mortality. However, no predictors were found of early degeneration of the valve in that patient population.

Total Endovascular Aortic Arch Repair Using 3-Vessel Inner Branch Stent Graft.

Endovascular repair has been introduced to decrease the morbidity and mortality associated with open surgical repair of aortic arch pathology. This case illustrates a 71-year-old male patient with an asymptomatic saccular aortic arch aneurysm treated by total endovascular aortic repair using 3-vessel inner branch stent graft. Postoperative course was unremarkable, and the patient was discharge home on postoperative day 3. Total endovascular aortic arch repair is a suitable alternative in higher-risk patients with aortic arch aneurysms who are not ideally suited for open surgical repair.

Early Hemodynamic Results in Patients With Small Aortic Annulus After Aortic Valve Replacement.

OBJECTIVE: Patients with a small aortic annulus (≤21 mm) have an increased risk of patient-prosthesis mismatch after valve replacement. The aim of this study was to compare the early hemodynamic performance of the balloon-expandable transaortic valve implantation Edwards system (SAPIEN) and the sutureless Perceval prostheses. METHODS: Fifty patients underwent transcatheter aortic valve implantation, and 113 patients underwent sutureless aortic valve replacement. Mean ± SD aortic annulus diameter was 19.7 ± 1 mm, with no significant difference between groups. SAPIEN valve size was 23 mm in 40 patients (80%) and 26 mm in 10 patients (20%). Perceval valve size was small in 45 patients (40%), medium in 62 patients (55%), and large in 6 patients (5%). Transthoracic Doppler echocardiographic images were collected at baseline and before discharge. RESULTS: There were no significant difference in predischarge effective orifice area (SAPIEN: 1.5 ± 0.5 cm and Perceval: 1.48 ± 0.34 cm, P = 0.58) and indexed effective orifice areas (SAPIEN: 0.93 ± 0.32 cm/m and Perceval: 0.88 ± 0.22 cm/m, P = 0.42). Predischarge mean ± SD transaortic gradient was lower with the SAPIEN than with Perceval valves (12 ± 6 and 17 ± 6 mm Hg, respectively, P < 0.001). Rates of moderate and severe prosthesis-patient mismatch were similar (SAPIEN: 44% and 10% and Perceval: 50% and 14%, P = 0.53 and 0.75, respectively). There were no moderate-severe paravalvular leaks. CONCLUSIONS: Although indexed effective orifice areas were similar, transcatheter aortic valve implantation with the balloon-expandable SAPIEN system yielded lower predischarge transaortic mean gradients than the surgically implanted Perceval, in patients with a small annulus.

The Ross procedure: biomechanical properties of the pulmonary artery according to aortic valve phenotype.

OBJECTIVES: The aim of this study is to determine whether patients undergoing the Ross procedure with bicuspid aortic valves have pulmonary artery biomechanical properties different from those with tricuspid valves. METHODS: Thirty-two pulmonary arteries and 20 aortas were obtained from patients undergoing the Ross procedure at the time of surgery, from a cohort of 32 patients. The aortic valve was tricuspid in 5 patients (16%), bicuspid in 18 patients (56%) and unicuspid in 9 patients (28%). Histological analysis and ex vivo equi-biaxial tensile testing completed within 8 hours of surgery were used to evaluate differences in patient groups and between the pulmonary artery and the ascending aorta. RESULTS: There was no difference in thickness among pulmonary arteries when compared according to aortic valve phenotype (P = 0.94). There was no difference in the tensile tissue properties among aortas and pulmonary arteries when compared according to aortic valve phenotype, in either the circumferential or longitudinal axis. When compared according to the main surgical indication, pulmonary artery walls from patients with pure aortic regurgitation were less stiff than their counterparts (aortic regurgitation: 0.055 ± 0.037 MPa, aortic stenosis: 0.103 ± 0.051 MPa, mixed disease: 0.110 ± 0.044 MPa and aortic valve endocarditis: 0.216 ± 0.033 MPa, P = 0.002). There was no difference in the number of elastic lamellae in pulmonary artery specimens from the three different aortic valve phenotypes, as well as in the aortic specimens. CONCLUSIONS: No significant differences were observed in the biomechanical properties of pulmonary arteries when compared according to aortic valve phenotype.

Aortic intramural hematoma progressing rapidly to aortic dissection.

A 73-year-old man presented with intermittent chest pain radiating to the back, which had started 12 hours earlier. On the day after emergency consultation, a thoracic scan showed an acute aortic intramural hematoma starting at the sinotubular junction with an ascending aorta diameter of 5.7 cm. One hour after the initial scan, the patient had acute chest pain followed by a loss of consciousness. A second scan was obtained 2 hours after the initial scan and showed a type A aortic dissection that extended from the sinotubular junction to the descending aorta.

Minimally invasive mitral valve surgery: influence of aortic clamping technique on early outcomes.

BACKGROUND: Several methods of aortic clamping have been described for minimally invasive mitral valve surgery (MIMVS). The aim of this study was to compare the endoaortic balloon occlusion technique with the transthoracic clamp approach in terms of perioperative outcomes. METHODS: Between May 2006 and October 2011, a total of 259 patients underwent MIMVS through a 4 to 5 cm right anterolateral minithoracotomy. In 243 (93.8%) of these, the aorta was clamped using either the endoaortic balloon occlusion technique (endoballoon, n = 140) or the transthoracic clamp technique (transthoracic, n = 103). RESULTS: Patients in the endoballoon group had significantly longer operating time (4.3 ± 1.0 hours vs 3.2 ± 0.8 hours, p < 0.001), cardiopulmonary bypass time (143 ± 44 minutes vs 111 ± 29 minutes , p < 0.001), and cross-clamp time (114 ± 38 minutes vs 86 ± 23 minutes , p < 0.001). Perioperative blood loss was higher in the endoballoon group (287 ± 239 mL vs 213 ± 189 mL, p = 0.008) as was the mean postoperative creatinine kinase-MB level (36 ± 44 µg/L vs 26 ± 12 µg/L, p = 0.011). The repair rate was 99% or greater in both groups (p = 0.99). All patients left the operating room with no or trivial residual mitral regurgitation on transesophageal echocardiographic evaluation. In the endoballoon group there was 1 stroke (1%) and 5 myocardial infarctions (4%), compared with 2 strokes (2%) in the transthoracic group (p = not significant). There were 4 cases of postoperative cardiogenic shock, all of which occurred in the endoballoon group (p = 0.14). In-hospital mortality occurred in 2 patients from each group (p = 0.99). CONCLUSIONS: Minimally invasive mitral valve surgery can be performed successfully using either the endoaortic balloon technique or the transthoracic clamp approach. However, the transthoracic technique results in shorter operation time, less perioperative bleeding and better myocardial protection.

Glucagon-like peptide 1 inhibits the sirtuin deacetylase SirT1 to stimulate pancreatic ß-cell mass expansion.

OBJECTIVE: The glucoincretin hormone glucagon-like peptide 1 (GLP-1) enhances glucose-stimulated insulin secretion and stimulates pancreatic ß-cell mass expansion. We have previously shown that the forkhead transcription factor FoxO1 is a prominent transcriptional effector of GLP-1 signaling in the ß-cell. FoxO1 activity is subject to a complex regulation by Akt-dependent phosphorylation and SirT1-mediated deacetylation. In this study, we aimed at investigating the potential role of SirT1 in GLP-1 action. RESEARCH DESIGN AND METHODS: FoxO1 acetylation levels and binding to SirT1 were studied by Western immunoblot analysis in INS832/13 cells. SirT1 activity was evaluated using an in vitro deacetylation assay and correlated with the NAD(+)-to-NADH ratio. The implication of SirT1 in GLP-1-induced proliferation was investigated by BrdU incorporation assay. Furthermore, we determined ß-cell replication and mass in wild-type and transgenic mice with SirT1 gain of function after daily administration of exendin-4 for 1 week. RESULTS: Our data show that GLP-1 increases FoxO1 acetylation, decreases the binding of SirT1 to FoxO1, and stunts SirT1 activity in ß-INS832/13 cells. GLP-1 decreases both the NAD(+)-to-NADH ratio and SirT1 expression in INS cells and isolated islets, thereby providing possible mechanisms by which GLP-1 could modulate SirT1 activity. Finally, the action of GLP-1 on ß-cell mass expansion is abolished in both transgenic mice and cultured ß-cells with increased dosage of SirT1. CONCLUSIONS: Our study shows for the first time that the glucoincretin hormone GLP-1 modulates SirT1 activity and FoxO1 acetylation in ß-cells. We also identify SirT1 as a negative regulator of ß-cell proliferation.

Role of sensory activity on chemospecific populations of interneurons in the adult olfactory bulb.

The olfactory bulb (OB) retains a remarkable capacity to renew its interneuronal populations throughout the lifespan of animals. Neuronal precursors giving rise to the bulbar interneurons are generated in the subventricular zone and have to migrate long distances before reaching the OB. In the adult OB these neuronal precursors differentiate into distinct neuronal types, including GABAergic cells located in the granule cell layer and a diverse set of neurons in the glomerular layer comprising GABAergic and dopaminergic interneurons, as well as other neuronal subtypes expressing calretinin and calbindin. While the role of sensory activity in the integration and/or survival of newly generated cells in the olfactory system is well established, very little is known about how odorant-induced activity affects fate specification of newborn cells as well as survival and fate maintenance of preexisting neuronal populations generated in adulthood. The present study demonstrates that sensory deprivation diminishes not only the number of newborn cells in the OB, but also reduces the density of granule and periglomerular cells generated before nostril occlusion. It also shows that sensory activity has an important influence on the development and expression of dopaminergic, but not GABAergic, calretinin or calbindin phenotypes. Our data reveal that odorant-induced activity is important for the survival of both newborn and preexisting OB interneurons generated at adulthood and suggests that these chemospecific populations are differentially affected by sensory deprivation.