Minimally invasive versus conventional sternotomy for Mitral valve repair: protocol for a multicentre randomised controlled trial (UK Mini Mitral).

INTRODUCTION: Numbers of patients undergoing mitral valve repair (MVr) surgery for severe mitral regurgitation have grown and will continue to rise. MVr is routinely performed via median sternotomy; however, there is a move towards less invasive surgical approaches.There is debate within the clinical and National Health Service (NHS) commissioning community about widespread adoption of minimally invasive MVr surgery in the absence of robust research evidence; implementation requires investment in staff and infrastructure.The UK Mini Mitral trial will provide definitive evidence comparing patient, NHS and clinical outcomes in adult patients undergoing MVr surgery. It will establish the best surgical approach for MVr, setting a standard against which emerging percutaneous techniques can be measured. Findings will inform optimisation of cost-effective practice. METHODS AND ANALYSIS: UK Mini Mitral is a multicentre, expertise based randomised controlled trial of minimally invasive thoracoscopically guided right minithoracotomy versus conventional sternotomy for MVr. The trial is taking place in NHS cardiothoracic centres in the UK with established minimally invasive mitral valve surgery programmes. In each centre, consenting and eligible patients are randomised to receive surgery performed by consultant surgeons who meet protocol-defined surgical expertise criteria. Patients are followed for 1 year, and consent to longer term follow-up.Primary outcome is physical functioning 12 weeks following surgery, measured by change in Short Form Health Survey (SF-36v2) physical functioning scale. Early and 1 year echo data will be reported by a core laboratory. Estimates of key clinical and health economic outcomes will be reported up to 5 years.The primary economic outcome is cost effectiveness, measured as incremental cost per quality-adjusted life year gained over 52 weeks following index surgery. ETHICS AND DISSEMINATION: A favourable opinion was given by Wales REC 6 (16/WA/0156). Trial findings will be disseminated to patients, clinicians, commissioning groups and through peer reviewed publication. TRIAL REGISTRATION NUMBER: ISRCTN13930454.

Outcomes in minimally invasive double valve surgery.

OBJECTIVE: To review current literature evidence on outcomes of minimally invasive double valve surgeries (MIS). METHODS: A comprehensive electronic literature search was done from inception to 20th June 2020 identifying articles that discussed outcomes of minimally invasive approach in double valve surgeries either as a solo cohort or as comparative to conventional sternotomies. No limit was placed on time and place of publication and the evidence has been summarized in narrative manner within the manuscript. RESULTS: Majority of current literature reported similar perioperative and clinical outcomes between MIS and conventional median sternotomy; except that MIS has better cosmetic effects and pain control. Nevertheless, minimal invasive techniques are associated with longer cardiopulmonary bypass and aortic cross-clamp times which may have impact on the reported outcomes and overall morbidity and mortality rates. CONCLUSION: Minimally invasive double valve surgery continues to develop, but scarcity in the literature suggests uptake is slow, possibly due to the learning curve associated with MIS. Many outcomes appear to be comparable to conventional sternotomy. There is need for larger, multi-center, and randomized trial to fully evaluate and establish the early, mid- and long-term morbidity and mortality rates associated with both techniques.

Endoscopic Tricuspid Valve Surgery is a Safe and Effective Option.

OBJECTIVE: Isolated tricuspid surgery through median sternotomy can be associated with a high morbidity and mortality. Reports of minimally invasive isolated tricuspid valve operations are rare, but the outcomes are encouraging. We present our experience of endoscopic isolated tricuspid valve surgery. METHODS: In our institution, 452 patients underwent endoscopic minimal access cardiac surgery between August 2008 and December 2018. A total of 90 patients underwent tricuspid valve surgery whether isolated or with other cardiac procedure. We further selected patients who had isolated tricuspid valve surgery (n = 24). Of these patients, 13 (54%) had more than one previous sternotomy. RESULTS: Tricuspid repair was performed in 18 patients (75%) with the remaining 6 (25%) having bioprosthetic tricuspid replacement. Three (12.5%) were performed with a beating heart, the remaining with endoaortic clamping and cardioplegia. There were no conversions to sternotomy. None of the patients had reoperation for bleeding, tamponade, or valve issues. Three patients (12.5%) required blood transfusion, 3 patients (12.5%) required renal dialysis, and 7 patients (29%) had respiratory complications such as chest infection, requiring continuous positive airway pressure (CPAP) with 2 being re-intubated. One patient (4.1%) died within 30 days from chest sepsis leading to multi-organ failure. Mean hospital stay was 11.1 ± 8.9 days (median of 8). All patients had mild or less regurgitation on follow-up echo at 6 months. CONCLUSIONS: Isolated tricuspid valve surgery can be performed through an endoscopic minimally access approach, with good results. It appears to provide better results than a sternotomy approach. A high repair rate can be achieved, and the procedure is particularly valuable in redo-surgery with low mortality and morbidity compared to historical sternotomy case series.

Bridging to lung transplantation for severe pulmonary hypertension using dual central Novalung lung assist devices.

This case describes the technique of using dual Novalungs (a pumpless extracorporeal system) to bridge a patient with idiopathic pulmonary hypertension to bilateral lung transplantation. A 41-year old lady with idiopathic pulmonary hypertension (with a possible veno-occlusive element) presented with symptoms of end-stage heart and lung failure. This was refractory to medical management with iloprost, sildenafil and bosentan. The patient was placed on the urgent waiting list for lung transplantation and central pulmonary artery to left atrial Novalung insertion was performed. Local anaesthetic was given before performing peripheral cardiopulmonary bypass due to the high risk of cardiac arrest. Two days later, donor organs became available and the patient was taken for double-lung transplantation. The pulmonary artery cannula was removed leaving a large defect. This was then closed using a bovine pericardial patch. Due to the damaged right superior pulmonary vein from Novalung cannulation, cardioplegia was given to facilitate an open atrial anastomosis. After 13 days in the intensive therapy unit, she was transferred to the ward. There were no further complications and she has been discharged home.

A case series of myectomy: a review of its current application as an adjunct procedure.

In this article, we review the role played by myectomy in cardiac surgery. For this purpose, we looked at three cases of different etiology where myectomy in conjunction with treatment of the primary condition proved invaluable in the outcome of these patients. The primary conditions requiring treatment were subaortic membrane, hypertrophic obstructive cardiomyopathy with mitral valve regurgitation, and aortic stenosis.

Successful graft patency after factor VIIa use for bleeding in coronary artery surgery: an unusual complication of a coronary artery bypass surgery.

There is a growing literature regarding the use of recombinant activated factor VII (rFVIIa) (NovoSeven, NovoNordisk, Copenhagen, Denmark) to control refractory hemorrhage after cardiopulmonary bypass in cardiac surgery. This supporting evidence is mostly documented as case reports on patients, of which only six involve coronary artery grafting. We present our experience of a patient undergoing coronary artery bypass grafting, who suffered an anaphylactic reaction to protamine preventing safe reversal of systemic heparinization. Subsequent management of postoperative bleeding was successfully achieved only after rFVIIa administration.

Effects of cell saver autologous blood transfusion on blood loss and homologous blood transfusion requirements in patients undergoing cardiac surgery on- versus off-cardiopulmonary bypass: a randomised trial.

OBJECTIVE: Off-pump CABG is potentially associated with reduced intraoperative blood loss and homologous blood transfusion in comparison to on-pump CABG. In this randomised controlled study we investigated the effects of autologous cell saver blood transfusion on blood loss and homologous blood transfusion requirements in patients undergoing CABG on- versus off-CPB. METHODS: Eighty patients were randomised into one of four groups: (A) on-CPB with cell saver blood transfusion (CSBT), (B) on-CPB without CSBT, (C) off-pump with CSBT and (D) off-pump without CSBT. Volume of intraoperative autologous blood transfusion, postoperative mediastinal blood loss and homologous blood transfusion requirements were measured. Homologous blood was transfused when haemoglobin concentration fell below 8 g/dl postoperatively. Pre- and postoperatively prothrombin time and partial thromboplastin time were measured. RESULTS: Preoperative patient characteristics were well matched among the four groups. The amount of salvaged mediastinal blood available for autologous transfusion was significantly higher in the on-pump group (A) compared to the off-CPB group (C) (433+/-155 ml vs 271+/-144 ml, P=0.001). Volume of homologous blood transfusion was significantly higher in group B vs groups A, C and D (595+/-438 ml vs 179+/-214, 141+/-183 and 230+/-240 ml, respectively, P<0.005). The cell saver groups (A and C) received significantly less homologous blood than the groups without cell saver (160+/-197 ml vs 413+/-394 ml, respectively, P<0.005). Patients undergoing off-CPB surgery received significantly less homologous blood than those undergoing on-CPB CABG irrespective of cell saver blood transfusion (184+/-214 ml vs 382+/-397 ml, P<0.05). Postoperative blood loss was similar in the four groups (842+/-276, 1023+/-291, 869+/-286 and 903+/-315 ml in groups A to D, respectively, P>0.05). Clotting test results revealed no significant difference between the groups. There was no significant difference in postoperative morbidity between groups. CONCLUSION: Off-pump CABG is associated with significant reduction in intraoperative mediastinal blood loss and homologous transfusion requirements. Autologous transfusion of salvaged washed mediastinal blood reduced homologous transfusion significantly in the on-CPB group. Cell saver caused no significant adverse impact on coagulation parameters in on- or off-CPB CABG. Postoperative morbidity and blood loss were not affected by the use of CPB or autologous blood transfusion. We recommend the use of autologous blood transfusion in both on- and off-pump CABG surgery.

How safe is it to train residents to perform off-pump coronary artery bypass surgery?

BACKGROUND: The technique of off-pump coronary artery bypass graft (OPCABG) surgery differs considerably from on-pump CABG. This study investigates the impact of surgical training on clinical outcome in patients undergoing OPCABG. METHODS: All 251 OPCABG cases performed by one service over an 18-month period were analyzed. The 83 operations (33%) performed by two trainees under supervision were compared with the 168 operations (67%) performed by an experienced consultant surgeon. Patient and disease characteristics, intraoperative and postoperative data, morbidity and mortality were analyzed using univariate and multivariate analysis. Data were extracted from a prospective database. RESULTS: Patients operated on by the consultant were more likely to have had unstable angina (p = 0.003, odds ratio [OR] = 3.5), impaired left ventricular function (ejection fraction < 0.3; p = 0.005, OR = 2.4), or previous cardiac surgery (p = 0.03). They were more likely to receive three or more grafts (p = 0.017, OR = 2.0). Operative mortality was 2.4% (consultant) and 0% (trainees; p = 0.31). Postoperative morbidity, such as reoperation for bleeding (consultant 3% versus trainees 1.2%), stroke (0.6% versus 1.2%), and hemofiltration (3.6% versus 0%) was similar between the two patient groups. Stay in the intensive care unit was not significantly different in the two groups. CONCLUSIONS: In our experience, trainee surgeons are less likely to operate on patients with unstable angina or cardiac dysfunction. Operative morbidity and mortality are, however, similar in patients operated on by either an experienced consultant surgeon or trainees. We believe OPCABG can be taught safely to trainees under supervision.

Complex off-pump coronary artery bypass surgery can be safely taught to cardiothoracic trainees.

OBJECTIVES: Off-pump coronary revascularisation is demanding technically as the surgeon is faced with a beating heart and not a bloodless field. The potential clinical advantages of off-pump coronary revascularisation have made this procedure an essential part of a cardiothoracic training program. The aim of this study is to investigate the impact of teaching trainees complex off-pump coronary artery surgery (arterial grafting, 'Y' grafts, sequential grafting and minimally invasive direct coronary artery bypass) on clinical outcomes. METHODS: All 323 off-pump coronary revascularisation cases performed by one service over a 24-month period were analysed. The 125 (39%) operations performed by two trainees with previous exposure in on-pump surgery were compared with the 198 (61%) performed by an experienced consultant surgeon. Patient and disease characteristics, intra- and post-operative data, morbidity and mortality were analysed using uni- and multivariate analysis. RESULTS: The trainees performed 51% of the MIDCABs, 36% of the 'Y' grafts and 27.5% of the sequential grafts. The internal thoracic artery was used in 96% of the cases, radial artery in 49% and bilateral internal thoracic arteries in 11% equally distributed between trainees and consultant. The average number of grafts per case was 3.7 for the consultant and 3.3 for the trainees. Patients operated by the consultants were more likely to have unstable angina (P=0.008), ejection fraction <30% (P=0.01) previous cardiac surgery (P=0.027) and more likely to receive over 4 grafts (P=0.01). Operative mortality was 1.5% for the consultant and 0 for the trainees (P=0.17). Post-operative morbidity, such as re-operation for bleeding (consultant 1% vs. trainee 0.8%), stroke (0.5% vs. 0.8%), haemofiltration (3.5% vs. 0.8%) was similar between the two groups. Hospital stay was also similar. CONCLUSIONS: The results of this study suggest that trainees under supervision perform complex off-pump coronary artery surgery safely with low rate of mortality and complications. These findings are in agreement with previous literature reports. Trainees should be allowed to operate on sufficient number of patients undergoing off-pump surgery according to their skills and abilities. Patients should be reassured that safety is not compromised by the presence of a trainee as a primary surgeon.