Early and Late Outcomes After Minimally Invasive Mitral Valve Repair Surgery.

BACKGROUND AND AIM OF THE STUDY: The practice of thoracoscopic assisted minimally invasive mitral valve repair surgery is less common in the United Kingdom than in Europe or the USA. The main reasons for this are concerns around increased operative risk, feasibility and durability of valve repair. The study aim was to report the early and late outcomes of minimally invasive mitral valve repair surgery at a single U.K. center. METHODS: Patients undergoing isolated minimally invasive mitral valve repair between 2003 and 2013 were reviewed retrospectively. Data were obtained from a prospectively maintained institutional database, a comprehensive review of individual case notes, echocardiograms, intensive care charts, clinic letters, discharge summaries, and the authors' follow up database (based on data supplied by the UK Office for National Statistics). RESULTS: A total of 190 patients (mean age 61 years; mean EuroSCORE 3.9) underwent the procedure. The mean cardiopulmonary bypass and aortic cross-clamp times were 153 and 108 min, respectively. Rates of major postoperative complications were: reoperation for bleeding 3.7%, stroke 1.6%, intra-aortic balloon pump 2.1%, and venovenous hemofiltration 2.6%. The median intensive care stay was one day, and the median hospital stay five days (21.8% of patients were discharged by day 3). The 30-day mortality was 1.1% (n = 2). Echocardiography performed at discharge or six weeks postoperatively showed less than mild mitral regurgitation (MR) in 91.3%. The median duration of follow up was 57 months. During the entire follow up period, four patients (2.1%) underwent repeat surgery for recurrent MR (between 15 months and five years). Of 188 patients discharged from hospital, nine (4.8%) died during follow up: median 5.3 years (range 1.3- 10.7 years) post surgery. CONCLUSION: These data are the first from the U.K. demonstrating early and late outcomes after thoracoscopic assisted minimally invasive mitral valve repair surgery. The data establish the safety and efficacy of the technique and, importantly, lend further support towards a prospective randomized comparison of minimally invasive versus conventional mitral valve repair surgery.

Characterizing collagen scaffold compliance with native myocardial strains using an ex-vivo cardiac model: The physio-mechanical influence of scaffold architecture and attachment method.

Applied to the epicardium in-vivo, regenerative cardiac patches support the ventricular wall, reduce wall stresses, encourage ventricular wall thickening, and improve ventricular function. Scaffold engraftment, however, remains a challenge. After implantation, scaffolds are subject to the complex, time-varying, biomechanical environment of the myocardium. The mechanical capacity of engineered tissue to biomimetically deform and simultaneously support the damaged native tissue is crucial for its efficacy. To date, however, the biomechanical response of engineered tissue applied directly to live myocardium has not been characterized. In this paper, we utilize optical imaging of a Langendorff ex-vivo cardiac model to characterize the native deformation of the epicardium as well as that of attached engineered scaffolds. We utilize digital image correlation, linear strain, and 2D principal strain analysis to assess the mechanical compliance of acellular ice templated collagen scaffolds. Scaffolds had either aligned or isotropic porous architecture and were adhered directly to the live epicardial surface with either sutures or cyanoacrylate glue. We demonstrate that the biomechanical characteristics of native myocardial deformation on the epicardial surface can be reproduced by an ex-vivo cardiac model. Furthermore, we identified that scaffolds with unidirectionally aligned pores adhered with suture fixation most accurately recapitulated the deformation of the native epicardium. Our study contributes a translational characterization methodology to assess the physio-mechanical performance of engineered cardiac tissue and adds to the growing body of evidence showing that anisotropic scaffold architecture improves the functional biomimetic capacity of engineered cardiac tissue. STATEMENT OF SIGNIFICANCE: Engineered cardiac tissue offers potential for myocardial repair, but engraftment remains a challenge. In-vivo, engineered scaffolds are subject to complex biomechanical stresses and the mechanical capacity of scaffolds to biomimetically deform is critical. To date, the biomechanical response of engineered scaffolds applied to live myocardium has not been characterized. In this paper, we utilize optical imaging of an ex-vivo cardiac model to characterize the deformation of the native epicardium and scaffolds attached directly to the heart. Comparing scaffold architecture and fixation method, we demonstrate that sutured scaffolds with anisotropic pores aligned with the native alignment of the superficial myocardium best recapitulate native deformation. Our study contributes a physio-mechanical characterization methodology for cardiac tissue engineering scaffolds.

The pectus care guidelines: best practice consensus guidelines from the joint specialist societies SCTS/MF/CWIG/BOA/BAPS for the treatment of patients with pectus abnormalities.

Pectus defects are a group of congenital conditions found in approximately 1 in 250 people, where the sternum is depressed back towards the spine (excavatum), protrudes forwards (carinatum) or more rarely is a mixture of both (arcuatum or mixed defects). For the majority of patients, it is well tolerated, but some patients are affected psychologically, physiologically or both. The deformity becomes apparent at a young age due to the growth of the ribs and the cartilage that links them to the sternum. The majority of defects are mild and are well tolerated, i.e. they do not affect activity and do not cause psychological harm. However, some young people develop lower self-esteem and depression, causing them to withdraw from activities (such as swimming, dancing) and from interactions that might 'expose' them (such as sleepovers, dating, going to the beach and wearing fashionable clothes). This psychological harm occurs at a crucial time during their physical and social development. A small number of patients have more extreme depression of their sternum that impedes their physiological reserve, which can occur when engaging in strenuous exercise (such as running) but can also limit moderate activity such as walking and climbing stairs. The effects can be so extreme that symptoms occur at rest or cause life-threatening compression of the major blood vessels and organs. The group of patients with physiological impairment usually also suffer from low self-esteem and depression. This paper summarizes the current evidence for the different treatment strategies for this condition, including supportive care, psychological support and non-surgical techniques including bracing and vacuum bell therapy. We also consider surgical techniques including the Ravitch procedure, the Nuss procedure (minimally invasive repair of pectus excavatum), pectus implants and other rare procedures such as Pectus Up. For the majority of patients, supportive care is sufficient, but for a minority, a combination of the other techniques may be considered. This paper also outlines best practice guidance for the delivery of such therapies, including standardized assessment, consent to treatment, audit, quality assurance and long-term support. All the interventions have risks and benefits that the patient, parents and clinicians need to carefully consider and discuss when deciding on the most appropriate course. We hope this evidence review of 'Best Practice for Pectus' will make a significant contribution to those considerations and help all involved, from patients to national policy makers, to deliver the best possible care.

How do surgeons decide? Conduit choice in coronary artery bypass graft surgery in the UK†.

OBJECTIVES: Conduits used in coronary artery bypass grafting may have significant impact on outcomes, but evidence is mixed and there is large variation in practice. This study provides insights into the opinions of the UK surgeons on conduit use and their decision-making processes. METHODS: A questionnaire was created using the Ottawa Decision Support Framework to elicit the importance that surgeons placed on bilateral internal mammary artery grafting, skeletonization, total arterial revascularization and sequential anastomoses on a scale of 1-10. Scores ≥8 were deemed 'important' and ≤3 'not important'. Surgeons were asked to specify changes to practice in frail patients or emergencies. Additional questions included conduit type used, factors affecting decision-making and vein harvesting methods. Questionnaires were administered in person with data analysed centrally. RESULTS: Ninety-seven consultant cardiac surgeons from 25 centres responded. Thirty-two percent surgeons routinely used radial arteries and 36% used right internal mammary artery. High-quality evidence contributed most to decision-making receiving a total of 328/960 points, with consultant experience being the second (255/960 points). There was a bimodal distribution of perceived importance of bilateral internal mammary artery use, with 29 (30%) 'important' and 'not important' scores each. 23% of surgeons found total arterial revascularization important. Most surgeons (64%) preferred pedicled mammary arteries. Twenty-six percent of surgeons considered sequential grafting to be important. CONCLUSIONS: Low uptake of total arterial revascularization and bilateral internal mammary artery among the UK consultants may be due to the lack of high-quality evidence demonstrating a significant benefit. It is also possible that reluctance to use certain conduits may stem from low levels of exposure to conduits or inadequate training, particularly given the importance of consultant experience on decision-making.

Suction on chest drains following lung resection: evidence and practice are not aligned.

OBJECTIVES: A best evidence topic in Interactive CardioVascular and Thoracic Surgery (2006) looked at application of suction to chest drains following pulmonary lobectomy. After screening 391 papers, the authors analysed six studies (five randomized controlled trials [RCTs]) and found no evidence in favour of postoperative suction in terms of air leak duration, time to chest drain removal or length of stay. Indeed, suction was found to be detrimental in four studies. We sought to determine whether clinical practice is consistent with published evidence by surveying thoracic units nationally and performing a meta-analysis of current best evidence. METHODS: We systematically searched MEDLINE, EMBASE and CENTRAL for RCTs, comparing outcomes with and without application of suction to chest drains after lung surgery. A meta-analysis was performed using RevMan(©) software. A questionnaire concerning chest drain management and suction use was emailed to a clinical representative in every thoracic unit. RESULTS: Eight RCTs, published 2001-13, with 31-500 participants, were suitable for meta-analysis. Suction prolonged length of stay (weighted mean difference [WMD] 1.74 days; 95% confidence interval [CI] 1.17-2.30), chest tube duration (WMD 1.77 days; 95% CI 1.47-2.07) and air leak duration (WMD 1.47 days; 95% CI 1.45-2.03). There was no difference in occurrence of prolonged air leak. Suction was associated with fewer instances of postoperative pneumothorax. Twenty-five of 39 thoracic units responded to the national survey. Suction is routinely used by all surgeons in 11 units, not by any surgeon in 5 and by some surgeons in 9. Of the 91 surgeons represented, 62 (68%) routinely used suction. Electronic drains are used in 15 units, 10 of which use them routinely. CONCLUSIONS: Application of suction to chest drains following non-pneumonectomy lung resection is common practice. Suction has an effect in hastening the removal of air and fluid in clinical experience but a policy of suction after lung resection has not been shown to offer improved clinical outcomes. Clinical practice is not aligned with Level 1a evidence.

Left-handed cardiac surgery: tips from set up to closure for trainees and their trainers.

There are certain obstacles which left-handed surgeons can face when training but these are not necessary and often perpetuated by a lack of knowledge. Most have been encountered and overcome at some point but unless recorded and disseminated they will have to be resolved repeatedly by each trainee and their trainers. This article highlights difficulties that the left-hander may encounter in cardiac surgery and gives practical operative advice for both trainees and their trainers to help overcome them.

Left-handed surgical instruments - a guide for cardiac surgeons.

For ease of use and to aid precision, left-handed instruments are invaluable to the left-handed surgeon. Although they exist, they are not available in many surgical centres. As a result, most operating theatre staff (including many left-handers) have little knowledge of their value or even application. With specific reference to cardiac surgery, this article addresses the ways in which they differ, why they are needed and what is required - with tips on use.

Thermoreactive clips do not reduce sternal infection: a propensity-matched comparison with sternal wires.

OBJECTIVES: Sternal stability is essential to prevent serious infective complications after sternotomy. This paper examines whether nitinol thermoreactive clips reduce sternal wound infection rates in obese patients [body mass index (BMI) ≥30] compared with sternal wires. METHODS: All patients with BMI ≥30 undergoing cardiac surgery via median sternotomy between February 2008 and February 2013 in our institution were divided into two groups depending on sternal closure technique-sternal wires or thermoreactive clips. Comparison was made using propensity-matched analysis with sternal wound infection as the primary outcome. RESULTS: Of 1371 patients, 826 (60%) had thermoreactive clips and 545 (40%) sternal wires. The sternal wires group was older (mean age 66.62 ± 10.1 vs 64.35 ± 9.8 years, P = 0.00) with a greater proportion of females (39 vs 26%, P = 0.00). In unmatched group comparison, both superficial sternal wound infection (thermoreactive clips 4% vs wires 3%) and deep infection (thermoreactive clips 3% vs wires 0.6%, P = 0.00) were more common in the thermoreactive clips group. More patients in the thermoreactive clips group required debridement and a larger number had vacuum-assisted closure [thermoreactive clips 10 patients (1%) vs sternal wires 2 (0.4%)]. Propensity-matching yielded two groups of 356 patients. There was no difference in sternal wound infection rates [thermoreactive clips 19 patients (5%) vs sternal wires 15 (4%), P = 0.58] or deep sternal infection rates [thermoreactive clips 9 patients (3%) vs sternal wires 3 (1%), P = 0.11]. CONCLUSIONS: Thermoreactive clips did not have an advantage in the prevention of superficial or deep sternal wound infection in obese patients undergoing sternotomy.

Manubrium-limited sternotomy decreases blood loss after aortic valve replacement surgery.

OBJECTIVES: Minimally invasive surgical approaches for aortic valve replacement (AVR) are growing in popularity in an attempt to decrease morbidity from conventional surgery. We have adopted a technique that divides only the manubrium and spares the body of the sternum. We sought to determine whether patients benefit from this less-invasive approach. METHODS: We retrospectively analysed our prospectively maintained database to review all isolated aortic valve replacements performed in an 18-month period from November 2011 to April 2013. RESULTS: One hundred and ninety-one patients were identified, 98 underwent manubrium-limited sternotomy (Mini-AVR) and 93 had a conventional median sternotomy (AVR). The two groups were well matched for preoperative variables and risk (mean logistic EuroSCORE mini-AVR 7.15 vs AVR 6.55, P = 0.47). Mean cardiopulmonary bypass and aortic cross-clamp times were 10 and 6 min longer, respectively, in the mini-AVR group (mean values 88 vs 78 min, P = 0.00040, and 66 vs 60 min, P = 0.0078, respectively). Mini-AVR patients had significantly less postoperative blood loss, 332 vs 513 ml, P = 0.00021, and were less likely to require blood products (fresh-frozen plasma and platelets), 24 vs 36%, P = 0.042. Postoperative complications and length of stay were similar (discharge on or before Day 4; mini-AVR 15 vs AVR 8%, P = 0.17). Valve outcome (paravalvular leak mini-AVR 2 vs AVR 1%, P = 1.00) and survival (mini-AVR 99 vs AVR 97%, P = 0.36) were equal. CONCLUSIONS: A manubrium-limited approach maintains outcomes achieved for aortic valve replacement by conventional sternotomy while significantly reducing postoperative blood loss and transfusion of blood products.

Comparison of single lung transplant with and without the use of cardiopulmonary bypass.

OBJECTIVES: Many centres avoid using cardiopulmonary bypass (CPB) for lung transplant due to concerns over aggravated lung reperfusion injury and excessive blood loss. We reviewed our 23-years' experience of single lung transplantation. METHODS: A retrospective review of single lung transplants at our institution (1987-2010), examining differences in allograft function and postoperative complications between CPB and non-bypass (non-CPB) cases. RESULTS: Two hundred and fifty-nine single lung transplants were undertaken. Fifty-three (20.5%) with CPB. There was no difference demographically between the two groups. No difference existed in preoperative PO(2)/FiO(2). At 1 and 24 h, the postoperative PO(2)/FiO(2) ratio was no different (mean 2.95 and 3.24 in non-CPB cases; 3.53 and 3.75 in CPB patients, P = 0.18 and P = 0.34, respectively). Extubation time was not influenced by the use of CPB. Postoperative blood loss was greater in the CPB group. The usage of fresh frozen plasma and platelets was similar (P = 0.64 and 0.41, respectively). More blood was transfused during postoperative care of CPB patients (P = 0.02). CONCLUSIONS: Fears of poor postoperative lung function after CPB appear unfounded. We could detect no difference in function or extubation time. Although the use of CPB increases postoperative bleeding and the need for transfusion, it may be used safely to facilitate lung transplantation.

Invasive biopsy is effective and useful after lung transplant.

BACKGROUND: Transbronchial biopsy (TBB) is widely used after lung transplant but may not be diagnostic. Our group has used invasive approaches, open lung biopsy (OLB) or video-assisted thoracoscopy (VAT), to establish a definitive diagnosis in unexplained clinical deterioration. We sought to demonstrate the risks and benefits of this approach. METHODS: A retrospective review was made of the case notes of the patients undergoing OLB or VAT during a 12-year period from August 1996. RESULTS: During a 12-year period in 442 recipients, there were 51 invasive biopsies in 45 patients (6 had 2 procedures), of which 41 (80%) were OLB and 10 (20%) were VAT. Time of biopsy ranged from 7 days to 11 years after transplant. Thirty-seven (73%) took place in the first year, including 12 (24%) within the first 30 days. Nine patients died within 30 days of biopsy; 7 of them were already ventilated. Overall, biopsy provided a new unsuspected diagnosis in 37% of patients and confirmed the diagnostic suspicion in 47%. In only 16% of patients did it fail to provide a result that was clinically useful. The results of 29 (57%) biopsies led to a change in treatment. Sixty-three percent of new diagnoses and 71% where clinical suspicion was confirmed resulted in a treatment change. In all but 2 cases, a change was made to medication. CONCLUSIONS: In this large series of invasive biopsies, there was a high rate of useful results, with a frequent change in treatment. Invasive biopsies are a safe intervention in ambulatory patients.