The Future of Open Heart Surgery in the Era of Robotic and Minimal Surgical Interventions.

It has been over two decades since the very first robotic cardiac surgery was performed. Over the years, there has been an increase in the demand for less invasive cardiac surgical techniques. Developments in technology and engineering have provided an opportunity for robotic surgery to be applied to a variety of cardiac procedures, including coronary revascularisation, mitral valve surgery, atrial fibrillation ablation, and others. In coronary revascularisation, it is becoming more widely used in single vessel, as well as hybrid coronary artery approaches. Currently, several international centres are specialising in a totally endoscopic coronary artery bypass surgery involving multiple vessels. Mitral valve and other intracardiac pathologies such as atrial septal defect and intracardiac tumour are also increasingly being addressed robotically. Even though some studies have shown good results with robot-assisted cardiac surgery, there are still concerns about safety, cost and clinical efficacy. There are also limitations and additional challenges with the management of cardiopulmonary bypass and myocardial protection during robotic surgery. Implementing novel strategies to manage these challenges, together with careful patient selection can go a long way to producing satisfactory results. This review examines the current evidence behind robotic surgery in various aspects of cardiac surgery.

Long saphenous vein harvesting techniques and their effect on graft patency.

Coronary artery bypass grafting is a key cardiac surgery procedure and is the main treatment for patients with multivessel coronary artery disease. The most frequently used conduit for this procedure is the long saphenous vein (LSV). The technique of harvesting the LSV has evolved over the last 30 years from total open harvesting to endoscopic with minimal access technique. The most important determining factor for success in coronary artery surgery is the graft patency rate. The literature evidence behind each technique has been reported at different levels and there is an ongoing debate about which technique can provide optimum vein patency over the long term. This literature review aims to summarize the current evidence, the implications involved with the use of each technique for harvesting LSV and the patency rate at variable follow-up intervals.

Long-Term Survival and Freedom From Reintervention After Off-Pump Coronary Artery Bypass Grafting: A Propensity-Matched Study.

BACKGROUND: The long-term outcomes of off-pump coronary artery bypass grafting (CABG) are the subject of speculation. Our institution has >15 years of experience performing CABG both off-pump (OPCAB) and on cardiopulmonary bypass (CPB). Our null hypothesis was that there would be no difference in a long-term composite of death and revascularisation between the 2 methods. METHODS: We performed a retrospective cohort study of all isolated CABG at our institution from 2001 to 2015. We used an intention-to-treat analysis, performing risk adjustment with adjustment for and matching to propensity score. In total, 13 226 patients had CABG: 5882 had OPCAB and 7344 had CPB, with a median follow-up of 6.2 years. RESULTS: Of the 5882 OPCAB, 76 (1.3%) converted to CPB. One-, 5-, and 10-year survivals in each group were similar (OPCAB vs CPB: 96.7%, 87.9%, 72.1% vs 96.2%, 87.4%, 72.8%). No difference was found in long-term survival (adjusted hazards ratio [HR] 1.03; 95% confidence interval [CI]: 0.94-1.11 for OPCAB vs CPB; P=0.56) or freedom from death and reintervention (HR 0.98; 95% CI: 0.92-1.06 for OPCAB vs CPB; P=0.23). Patients receiving OPCAB had higher EuroSCOREs (median [quartiles]: 2.81 [1.53-5.57] vs 2.73 [1.51-5.22]; P=0.01), fewer grafts (mean±SD: 3.0±0.9 vs 3.3±0.9; P<0.001), but more total arterial grafting (45.9% vs 8.4%; P<0.001). OPCAB also had more trainee first operators (15.3% vs 12.5%), lower cardiac enzyme rise, shorter length of stay, and fewer complications (such as myocardial infarction). CONCLUSIONS: OPCAB is associated with similar long-term outcomes to CABG performed on CPB in our institution. Our low conversion rate to CPB, while training junior surgeons, demonstrates that OPCAB can be taught safely. The number of grafts performed between the 2 approaches is clinically comparable, if statistically different, and appears to provide equal benefits to survival and freedom from reintervention as on-pump CABG.

Redo Coronary Artery Bypass Grafting in the era of Advanced PCI.

OBJECTIVE: To review the evidence behind the role and relevance of redo coronary artery bypass grafting (CABG) in the current practice of percutaneous coronary intervention (PCI). METHODS: A comprehensive electronic literature search was performed to identify articles that discuss the practice of PCI and redo CABG in patients that require coronary revascularization. All relevant studies are summarized in narrative manner to reflect current indications and preference. RESULTS: The advancement in utilization of PCI has reduced the rate of redo CABG in patients with previous CABG that requires revascularization of an already treated coronary disease or a new onset of coronary artery stenosis. Redo CABG is associated with satisfactory perioperative outcomes but higher mortality at immediate postoperative period when compared to PCI. CONCLUSION: Redo CABG patients are less likely to develop comorbidities associated with revascularisation, but the operative mortality is higher and long-term survival rates are similar in comparison to PCI. There is a need for further research into the role of redo CABG in the current advanced practice of PCI.

Left Atrial or Transeptal Approach for Mitral Valve Surgery: A Systematic Review and Meta-analysis.

To compare outcomes of mitral valve surgery through conventional left atriotomy and transeptal approach (TS). Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Primary outcomes were operative mortality and permanent pacemaker (PPM) implantation; secondary outcomes were new onset of atrial fibrillation (AF), stroke and operative times. Sixteen articles met the inclusion criteria with 4537 patients. Cardiopulmonary bypass was longer with TS (weighted mean differences - 16.44 minutes [-29.53, -3.36], P = 0.01). Rates of PPM implantation (risk ratio 0.65 [0.47, 0.89], P = 0.007) and new onset AF (risk ratio 0.87 [0.78, 0.97], P = 0.02) were higher with TS. Subgroup analysis of isolated mitral valve surgery cohort showed no difference in operative times, mortality, new onset of AF, stroke, and PPM implantation. There is equal outcomes between both approaches during isolated mitral valve surgery; however, TS was associated with longer operative times and higher postoperative AF and PPM rates when pooling combined procedures. A large randomized controlled trial is required to confirm those findings.

Skeletonized or Pedicled Harvesting of Left Internal Mammary Artery: A Systematic Review and Meta-analysis.

We sought to compare clinical outcomes in skeletonized versus pedicled left internal mammary artery (LIMA) grafts in elective coronary artery bypass grafting through a systematic review and meta-analysis. A comprehensive electronic literature search of PubMed, Ovid, Embase, and Scopus was conducted from inception to January 2020. Only short-term (30 days) studies which compared both techniques have been included in our analysis. Primary outcomes were post anastomosis flow rate and sternal wound infection rate (SWI); secondary outcomes were conduit length, acute myocardial infarction and 30-day mortality. Thirteen articles with a total of 6222 patients met the inclusion criteria. Except for the prevalence of diabetes mellitus being significantly lower in the skeletonized cohort (odds ratio [OR] 0.77 95% confidence interval [CI] [0.61, 0.97], P = 0.03), there were no differences in the preoperative demographics between the 2 groups. The skeletonized LIMA conduit was significantly longer when compared to the pedicled conduit (weighted mean difference -2.64 cm 95% CI [-3.71, -1.56], P < 0.0001). SWI rates were not significantly different in the skeletonized versus pedicled LIMA group (OR 0.71 95% CI [0.47, 1.06], P = 0.10). New onset of acute myocardial infarction and 30-day mortality rate was similar in the 2 groups (OR 1.04 and 0.97, respectively, P > 0.05 in both). The postanastomoses flow rate was higher in skeletonized LIMA (Weighted Mean Difference -11.51 mL/min 95% CI [-20.54, -2.49], P < 0.01). Harvesting the LIMA using the skeletonized technique is associated with higher postanastomosis flow rates and longer conduit lengths; with no difference in SWI and mortality rates when compared to the pedicled technique. We suggest that this technique should be adopted, particularly for BITA harvesting. However, further research is needed to provide clearer indications for both methods.

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.

Techniques and approaches for revascularisation of left heart coronary diseases.

Coronary artery disease and its associated clinical sequelae are a significant medical burden to clinicians and patients. Severe coronary artery disease presenting in the context of acute myocardial ischaemia, or stable plaques causing chronic symptoms despite best conservative and pharmacological intervention, are often amenable to further intervention such as coronary artery bypass grafting. This procedure has been extensively compared to newer and less invasive techniques, such as percutaneous coronary intervention, and other minimally invasive procedures such as robotic or endoscopic techniques. This review summarises the current evidence on revascularisation of the left coronary artery system, with particular emphasis on key clinical endpoints of mortality, myocardial infarction, stroke and repeat revascularisation.

Surgical Treatment of Atrial Fibrillation: Cutting Through the Edges.

Medical management of atrial fibrillation can be complex, challenging and requiring time to prove its effectiveness; furthermore, the response can be refractory and inconsistent if the underlying pathology is not permanently addressed. Surgical ablation has become a key intervention, and since its first intervention in 1987 (the Cox-maze procedure), the technique has evolved from a conventional open method to a minimally invasive technique whilst retaining excellent outcomes. Furthermore, recent advances in the use of a hybrid approach have been established as satisfactory approach in managing atrial fibrillation with satisfactory outcomes. This literature review focuses on the evidence behind the surgical success in managing atrial fibrillation throughout the past, present and the future of these surgical interventions.

Redo Coronary Artery Bypass Grafting in the era of Advanced PCI

Abstract Objective: To review the evidence behind the role and relevance of redo coronary artery bypass grafting (CABG) in the current practice of percutaneous coronary intervention (PCI). Methods: A comprehensive electronic literature search was performed to identify articles that discuss the practice of PCI and redo CABG in patients that require coronary revascularization. All relevant studies are summarized in narrative manner to reflect current indications and preference. Results: The advancement in utilization of PCI has reduced the rate of redo CABG in patients with previous CABG that requires revascularization of an already treated coronary disease or a new onset of coronary artery stenosis. Redo CABG is associated with satisfactory perioperative outcomes but higher mortality at immediate postoperative period when compared to PCI. Conclusion: Redo CABG patients are less likely to develop comorbidities associated with revascularisation, but the operative mortality is higher and long-term survival rates are similar in comparison to PCI. There is a need for further research into the role of redo CABG in the current advanced practice of PCI.

Permanent Pacemaker Post Cardiac Surgery: where do we Stand?

Abstract Cardiac arrhythmias and requirement for permanent pacemaker (PPM) post open-heart surgery are some of the complications that can contribute to significant morbidities postoperatively and delay in normal recovery if not treated promptly. The reported rate of a PPM following isolated, elective coronary artery bypass grafting is < 1%, while following aortic or mitral valve surgery it is reported to be < 5%. There are several perioperative factors that can contribute to the increased likelihood of PPM requirement including preoperative rhythm, severity and location of cardiac ischaemia, perioperative variables, and the cardiac procedures performed. Optimization of such factors can possibly lead to a lower rate of PPM and, therefore, a lower rate of complications. This literature review focuses on PPM following each procedural type and how to minimize it.

Surgical treatment of atrial fibrillation: cutting through the edges

Abstract Medical management of atrial fibrillation can be complex, challenging and requiring time to prove its effectiveness; furthermore, the response can be refractory and inconsistent if the underlying pathology is not permanently addressed. Surgical ablation has become a key intervention, and since its first intervention in 1987 (the Cox-maze procedure), the technique has evolved from a conventional open method to a minimally invasive technique whilst retaining excellent outcomes. Furthermore, recent advances in the use of a hybrid approach have been established as satisfactory approach in managing atrial fibrillation with satisfactory outcomes. This literature review focuses on the evidence behind the surgical success in managing atrial fibrillation throughout the past, present and the future of these surgical interventions.

Should dialysis-dependent patients with upper limb arterio-venous fistulae undergoing coronary artery bypass grafting avoid having ipsilateral in situ mammary artery grafts?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether dialysis-dependent patients with upper limb arterio-venous fistulae (AVFs) undergoing coronary artery bypass grafting should avoid having ipsilateral in situ internal mammary artery (IMA) grafts. A literature search performed yielded 28 peer reviewed articles, of which 21 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The papers identified included 478 patients, of whom 219 had in situ IMA grafts with ipsilateral upper limb arterio-venous fistulae. There was a substantial variation between the papers, from single case reports to small retrospective cohort studies, but no randomized, controlled trials. The largest retrospective study included 155 patients and followed up for up to 5 years. Methods used to determine coronary steal included clinical assessment, electrocardiogram or echocardiographic changes, Doppler ultrasound of mammary arteries and angiography. The aggregate evidence suggested that 61 of the 219 patients with ipsilateral IMA grafts developed some clinical or physiological evidence of malperfusion during the use of the AVFs for dialysis. Comparisons with the contralateral IMA suggested that 27 of the 61 patients suffered similar problems when dialysis was applied. A number of studies used controls, including in situ right internal mammary artery (RIMA) flow and patients not on dialysis. In total, 32 patients had their in situ RIMA flow measurements studied, of which none showed any statistically significant flow alteration. While further strong evidence to demonstrate long-term outcomes is required, we recommend the avoidance, where possible, of ipsilateral in situ IMA grafts in patients with an upper limb AVF. There is sufficient experimental and anecdotal evidence to suggest that steal occurs and that in some patients, this has clinical implications on both morbidity and mortality. In this scenario, the use of the contralateral mammary is strongly advocated to maximize the patency of grafts in an already high-risk population.

Acute aortic dissection following non-structural failure of a prosthetic aortic valve.

Malfunction of a prosthetic aortic valve is associated with a spectrum of potentially life threatening complications. In addition, the risk of aortic dissection increases following aortic valve replacement, which relates principally to aortic root pathology rather than prosthetic type or its functional status (Circulation 100 (1999) II-287). We report a case in which a high velocity turbulent jet in the proximal aorta, resulting from prosthetic leaflet entrapment caused intimal injury with subsequent type I dissection. This highlights the desirability for regular surveillance following aortic valve replacement, particularly in those patients with an 'at-risk' aorta.