Unilateral versus bilateral cerebral perfusion during aortic surgery for acute type A aortic dissection: a multicentre study.

OBJECTIVES: The aim of this retrospective multicentre study was to investigate and compare clinical outcomes of unilateral and bilateral antegrade cerebral perfusion (ACP) strategies on cerebral protection during surgery for type A aortic dissection. METHODS: Data from 646 patients who underwent surgical repair of thoracic type A aortic dissection using unilateral and bilateral ACP with moderate hypothermic circulatory arrest in 3 cardiac surgical institutions between 2008 and 2018 were analysed. Propensity matching was performed to assess which technique ensured better outcomes. RESULTS: Unilateral and bilateral ACP techniques were performed in 250 (39%) and in 396 (61%) patients, respectively. Propensity score analysis identified 189 matched pairs. In the matched cohort, the lowest core temperature was 27.5°C and 28°C in the bilateral and unilateral groups, respectively (P < 0.001). The unilateral technique required significantly shorter aortic cross-clamp and cardiopulmonary bypass times than bilateral technique [82 min vs 100 min (P < 0.001); 170 min vs 195 min (P < 0.001)]. The 30-day mortality was comparable (P = 0.325). The bilateral group reported a significantly higher incidence of permanent neurologic deficits (P < 0.001), left brain hemisphere stroke (P = 0.007) and all-combined complications (P < 0.001). Ten-year survival was comparable (P = 0.45). CONCLUSIONS: Unilateral and bilateral ACP are both valid brain protection strategies in the landscape of aortic arch surgery. While admitting all the study limitations, unilateral technique could offer some clinical advantages. CLINICAL REGISTRATION NUMBER: 76049.

Eclipsed Functional Mitral Regurgitation Destabilizing Hypertrophic Cardiomyopathy: An Unusual Case Treated With MitraClip.

MitraClip (Abbott Laboratories, Abbott Park, IL) is validated in high-risk patients with severe degenerative mitral regurgitation (MR); however, it is not well established for functional MR in hypertrophic cardiomyopathy (HCM). We share a case of a 68-year-old man with HCM hospitalized for multiple incidents of acute pulmonary edema caused by a dynamic MR and successfully treated with the MitraClip device. Novel teaching points emerging from this case are that MRs in HCM can often be explained by mixed mechanisms, and properly identifying the MR mechanism is essential to choose optimal treatment. Furthermore, MitraClip can simultaneously treat MR secondarily to annular dilation and systolic anterior motion.

Il a été établi démque Le Mitraclip (Abbott Laboratories, Abbott Park, Il) est une intervention percutanée validée pour la prise en charge des patients à haut risque chirurgical qui présente une régurgitation mitrale (RM) sévère dégénérative. Toutefois, cette technique est moins bien établie dans une RM fonctionnelle dans le cadre d'une cardiomyopathie hypertrophique (CMH). Nous faisons part d'un cas d'un homme de 68 ans atteint d'une CMH et hospitalisé en raison de multiples œdèmes aigus du poumon causés une la RM dynamique dont le traitement par MitraClip s'est avéré une réussite. Les nouveaux d'enseignement à enseigner qui émergent de ce cas portent sur le fait que les RM dans le cadre d'une CMH s'expliquent souvent par des mécanismes mixtes et que la détermination exacte du mécanisme de la RM est essentielle pour choisir le traitement qui convient le mieux au patient. De plus, le MitraClip permet de traiter simultanément les deux mécanismes d'une RM due à une dilatation annulaire et au mouvement systolique antérieur.

Left ventricle reconstruction and heartmate3 implantation. The "double patch technique".

BACKGROUND: HeartMate 3 is a left ventricular assist device, composed of a centrifugal pump. It can be applied as a myocardial recovery, a bridge to transplant, or a destination therapy, in the treatment of patients with left ventricular heart failure. METHODS: Herein we describe a technique applied against a giant aneurysmal dilatation, which combines a surgical device implantation and a left ventricular reconstruction using a double patch. RESULTS: The patch minimizes thrombotic risk thanks to its internal bovine pericardium layer, which is in contact with blood. CONCLUSIONS: The outlined technique is relatively reproducible and safe in a selected group of patients, as it employs a high-quality device and enables the restoration of an appropriate ventricular geometry.

Rapid-deployment aortic valve replacement in high-risk patients with severe endocarditis.

BACKGROUND: Surgical management of aortic valve endocarditis in high risk patients is controversial and the ideal treatment has not been found yet. We describe a selected series of eight patients treated with rapid-deployment aortic valve prosthesis as a therapeutic solution for minimizing the risks associated with annulus manipulation in case of severe aortic infective endocarditis. METHODS: Eight consecutive patients (five men and three women) with a mean age of 74.3±7.2 years, mean logistic EuroSCORE II of 16.0%±0.1%, affected by aortic native (1 patient), or prosthetic valve endocarditis (7 patients), were treated with Edwards Intuity Elite implantation. Hemodynamic performance and infective data were collected pre-, intra-, and postoperatively with a mean follow-up of 2.7±0.7 years. RESULTS: One case of in-hospital mortality was noted. None of the patients had any embolic or infective complication postoperatively. The cardiopulmonary bypass and aortic cross-clamp times were 148.4±41.6 and 90.5±25.3 min, respectively. The postoperative echocardiographic controls indicated a mean transvalvular gradient of 16.7±3.0 mmHg and one case of paravalvular leaks (2 +). Two patients underwent epigastric permanent pacemaker implantation. During the follow-up, seven patients were alive, with no evidence of symptoms or recurrences of endocarditis or embolic episodes. No new paravalvular leaks were noted, and the mean gradient on the valves was 12.4±3.4 mmHg. CONCLUSIONS: Rapid deployment aortic valve replacement in selected very high-risk patients affected by infective endocarditis could be a reasonable choice with acceptable results. However, further studies are needed to confirm these results.

Animal Models of Repaired Tetralogy of Fallot: Current Applications and Future Perspectives.

Tetralogy of Fallot is the most common cyanotic congenital heart disease. Despite ongoing improvements in the initial surgical repair, there are lingering concerns regarding the long-term outcomes that may be complicated by right ventricular dysfunction, right ventricular dyssynchrony, and sudden cardiac death. The mechanisms leading to these late complications remain incompletely understood. Experimental animal models have been developed as preclinical steps to gain better insight into the pathophysiology of diseases and to develop new therapeutic strategies. This article summarizes the various types of experimental animal models of repaired tetralogy of Fallot published to date in the literature, with the aim of achieving a greater understanding of the deleterious mechanisms that may lead to these known late and sometimes lethal complications. In addition to analysing the type of animals that can be used according to a given study's objectives, needs, and constraints, the present review also evaluates the type of dysfunction that can be reproduced in our model according to the research objectives, as well as the different types of studies in which these models can be used. In view of all that, we propose a decision algorithm to create an animal model of repaired tetralogy of Fallot. This synthesis should furthermore help in the development of future studies and in the design of new experimental models, thus allowing greater insight into this disease, while not forgetting the ultimate goal of broadening future therapeutic measures to reduce the morbidity and mortality of this prevalent congenital heart disease.

Epicardial, Biatrial Ablation With Integrated Uni-bipolar Radiofrequency Technology in Stand-alone Persistent Atrial Fibrillation.

OBJECTIVE: Although minimally invasive approaches for surgical treatment of stand-alone atrial fibrillation have gained popularity for the past decade, ablation technology and extensive lesion sets play a major role in the achievement of a successful procedure, especially in presence of persistent and long-standing persistent atrial fibrillation. We evaluated clinical outcomes after totally endoscopic biatrial epicardial ablation of persistent atrial fibrillation with a novel integrated uni-bipolar radiofrequency device. METHODS: Forty-nine (49) consecutive patients with stand-alone atrial fibrillation underwent right-sided monolateral thoracoscopic surgical ablation with a novel integrated uni-bipolar radiofrequency energy delivery and temperature-controlled technology. Atrial fibrillation was persistent in 13 (26.5%) of 49 and long-standing persistent in 36 (73.5%) of 49 patients. Mean ± SD age was 60.6 ± 10.3 years. Median duration of atrial fibrillation was 74 months. Mean ± SD left atrial diameter was 44.7 ± 4.0 mm. RESULTS: Epicardial en bloc isolation of all pulmonary veins (box lesion) and additional ablation of the right atrial free wall was successfully performed via minimally invasive approach without any intraoperative and postoperative major complications. Intraoperative entrance and exit block was achieved in 77.5% (38/49) and 91.8% (45/49) of patients, respectively. Mean ± SD ablation time was 16.3 ± 4.8 minutes. No intensive care unit stay was required. Postoperative sinus rhythm was achieved in 93.8% (30/32) patients, and no pacemaker implantation was required. At 13 months, 87.7% (43/49) of patients were in sinus rhythm; 71.4% (35/49) were free from antiarrhythmic drugs and 75.5% (37/49) from oral anticoagulation. CONCLUSIONS: Integrated uni-bipolar radiofrequency ablation technology showed to be effective for the surgical treatment of atrial fibrillation with a total endoscopic approach. A versapolar suction device with extensive right-left atrial lesion set may further improve outcomes in patients with nonparoxysmal atrial fibrillation.

Early to mid-term results after total cavopulmonary connection performed in the second decade of life.

OBJECTIVES: Total cavopulmonary connection (TCPC) performed in the second decade of life has rarely been studied. Thus, we investigated (bicentric study) early and late morbidity and mortality following completion of TCPC in these patients. METHODS: From January 1999 to June 2014, 63 patients (14.5 ± 2.9 years) underwent TCPC (extracardiac conduit). Palliation before completion was an isolated bidirectional cavopulmonary shunt (BCPS) in 3 patients or BCPS associated with additional pulmonary blood flow (APBF) that was either antegrade (Group 1) in 38 (63%) or retrograde (Group 2) in 22 (37%). Preoperative and perioperative data were reviewed retrospectively. RESULTS: Mean pulmonary arterial and ventricular end-diastolic pressures were 12.2 and 9.2 mmHg, respectively. Mean Nakata index was 279 ± 123 and 228 ± 87 mm 2 /m 2 in Groups 1 and 2, respectively ( P = 0.01). Aortic cross-clamping was performed in 22 from Group 1 and 8 from Group 2 ( P = 0.04). Mean follow-up was 4.57 years [0.8-15]. Nine patients had prolonged stays in the intensive care unit (>6 days). There were 1 early and 2 late deaths (non-cardiac related). Actuarial survival was 96% at 4 years. At last follow-up, single-ventricle function remained normal or improved in all patients (Group 1) compared to 82% in Group 2 ( P = 0.02). New York Heart Association (NYHA) class had improved in both groups: 47 patients were NYHA class II and 16 class III preoperatively vs 50 class I and 10 class II postoperatively ( P < 0.001). CONCLUSIONS: Single-ventricle palliation with BCPS and APBF allowed completion of TCPC in the second decade of life, with encouraging mid-term results. However, BCPS with retrograde APBF was associated with single-ventricle dysfunction: thus, this technique needs to be used cautiously as long-lasting palliation.

Impact of Afterload Increase on Left Ventricular Myocardial Deformation Indices.

BACKGROUND: Left ventricular (LV) afterload could be associated with reduced myocardial contractility. The aim of this study was to evaluate the relative impact of increased afterload on LV myocardial deformation indices in chronic aortic constriction, with regard to hypertrophy, myocardial fibrosis, and mitochondrial function, and to differentiate acute versus chronic afterload effect. METHODS: Young pigs underwent aortic banding (n = 11) or sham (n = 7) operations. Nineteen weeks later, LV morphology and systolic function, including myocardial deformation, were assessed by echocardiography before and after banding release or acute aortic constriction (in the sham group). After the animals were euthanized, mitochondrial function and LV interstitial fibrosis were assessed. RESULTS: The chronic banding group (n = 8) presented with significant LV hypertrophy compared with the sham group (n = 7), and longitudinal strain (LS) was significantly altered (16.9 ± 0.7% vs 20.3 ± 0.7%, P = .001) while circumferential, radial strain, and ejection fraction were not. LS abnormalities were situated mostly on the basal and mid segments and on the septal wall. There was also significantly more myocardial fibrosis in the chronic banding group compared with the sham group, while mitochondrial function was preserved. The relative contributions of hypertrophic and fibrotic remodeling and of afterload to alter global LS were 62%, and 38%, respectively. Acute aortic banding also significantly altered LS. The ratio of LS to septal wall thickness enabled differentiation between chronic and acute afterload increase (1.9 ± 0.2 in the chronic group vs 2.9 ± 0.3 in the acute group, P = .001). CONCLUSIONS: LS is susceptible to both hypertrophic and fibrotic remodeling and afterload increase, particularly on the basal and mid LV segments of the septum. The ratio of LS to septal wall thickness enables differentiation of acute from chronic afterload LS alteration.

Gli3 regulation of myogenesis is necessary for ischemia-induced angiogenesis.

RATIONALE: A better understanding of the mechanism underlying skeletal muscle repair is required to develop therapies that promote tissue regeneration in adults. Hedgehog signaling has been shown previously to be involved in myogenesis and angiogenesis: 2 crucial processes for muscle development and regeneration. OBJECTIVE: The objective of this study was to identify the role of the hedgehog transcription factor Gli3 in the cross-talk between angiogenesis and myogenesis in adults. METHODS AND RESULTS: Using conditional knockout mice, we found that Gli3 deficiency in endothelial cells did not affect ischemic muscle repair, whereas in myocytes, Gli3 deficiency resulted in severely delayed ischemia-induced myogenesis. Moreover, angiogenesis was also significantly impaired in HSA-Cre(ERT2); Gli3(Flox/Flox) mice, demonstrating that impaired myogenesis indirectly affects ischemia-induced angiogenesis. The role of Gli3 in myocytes was then further investigated. We found that Gli3 promotes myoblast differentiation through myogenic factor 5 regulation. In addition, we found that Gli3 regulates several proangiogenic factors, including thymidine phosphorylase and angiopoietin-1 both in vitro and in vivo, which indirectly promote endothelial cell proliferation and arteriole formation. In addition, we found that Gli3 is upregulated in proliferating myoblasts by the cell cycle-associated transcription factor E2F1. CONCLUSIONS: This study shows for the first time that Gli3-regulated postnatal myogenesis is necessary for muscle repair-associated angiogenesis. Most importantly, it implies that myogenesis drives angiogenesis in the setting of skeletal muscle repair and identifies Gli3 as a potential target for regenerative medicine.