Controversies in cardiac surgery: left main coronary disease, arterial myocardial revascularization, and prosthetic valves in dialysis

For the podcast associated with this article, please visit https://academic.oup.com/eurheartj/pages/Podcasts. This Issue opens with the State of the Art Review article ‘The search for optimal antithrombotic therapy in transcatheter aortic valve implantation: facts and uncertainties’ by Jurrien ten Berg from the St. Antonius Hospital in Nieuwegein, the Netherlands, and colleagues.1 The authors note that transcatheter aortic valve implantation (TAVI) is a minimally invasive procedure, which is used frequently in patients with symptomatic severe aortic valve stenosis.2–7 Most patients undergoing TAVI are over 80 years of age with a high bleeding risk as well as a high thrombotic risk. Despite the increasing safety of the procedure, thrombo-embolic events [stroke and (subclinical) valve thrombosis] remain prevalent. As a consequence, antithrombotic prophylaxis is routinely used, and only recently new data on the efficacy and safety of antithrombotic drugs have become available. On the other hand, these antithrombotic drugs increase bleeding in a population with unique aortic stenosis-related bleeding characteristics (such as acquired von Willebrand factor defect and angiodysplasia). In this review, the authors discuss the impact of thrombo-embolic and bleeding events and the current optimal antithrombotic therapy based on registries and recent randomized controlled trials, and they also try to give a practical guide on how to treat these high-risk patients. Finally, they discuss knowledge gaps and future research needed to fill these gaps. Factors that favour choices between treatment pathways for left main coronary stenosis in patients with stable ischaemic heart disease. CABG, coronary artery bypass graft; LV, left ventricular; MVD, multivessel disease; OMT, optimal medical therapy; PCI, percutaneous coronary intervention.8 The Issue continues with a focus on Cardiac and Vascular Surgery. In the State of the Art Review article entitled ‘Left main coronary disease: evolving management concepts’, Paul Armstrong from the University of Alberta in Edmonton, Canada, and colleagues note that remarkable advances in the management of coronary artery disease have enhanced our approach to left main coronary artery (LMCA) disease.8 The traditional role of coronary artery bypass graft surgery has been challenged by the less invasive percutaneous coronary interventional approach.9–12 Additionally, major strides in optimal medical therapy now provide a rich menu of treatment choices in selected circumstances. Although an LMCA stenosis >70% is an acceptable threshold for revascularization, those patients with an LMCA narrowing between 40% and 69% present a more complex scenario (Figure 1). This review examines the relative merits of the different treatment options, addresses key diagnostic and therapeutic unknowns, and identifies future work likely to advance progress. Forest plot representing treatment effects for all outcomes by diabetes status. Hazard ratios and P-values are from adjusted models. Event rates are unadjusted. DSWI, deep sternal wound infection; MACE, major adverse cardiac events; MAG, multiple arterial grafting; MI, myocardial infarction; SAG, single arterial grafting.16 Coronary bypass grafting plays a key role in the treatment of patients with coronary artery disease.13–15 In a Clinical Research article entitled ‘Single versus multiple arterial grafting in diabetic patients at 10 years: the Arterial Revascularization Trial’, David Taggart from the University of Oxford in the UK, and colleagues evaluate the impact of multiple arterial grafting (MAG) vs. single arterial grafting (SAG) in a post-hoc analysis of 10-year outcomes in patients with diabetes mellitus (DM) from the Arterial Revascularization Trial.16 The primary endpoint was all-cause mortality and the secondary endpoint was a composite of major adverse cardiac events (MACE) at 10-year follow-up. Patients were stratified by diabetes status (non-DM and DM) and grafting strategy (MAG vs. SAG). A total of 3020 patients were included in the analysis; 716 (24%) had DM. Overall, 56% non-DM patients received MAG and 44% received SAG, while 57% DM patients received MAG and 43% received SAG. The use of MAG compared with SAG was associated with a non-significant lower 10-year mortality in non-DM and a significant lower mortality in DM patients [adjusted hazard ratio (HR) 0.65; P for interaction = 0.12]. For both groups, the rate of 10-year MACE was also lower for MAG vs. SAG. Overall, deep sternal wound infections were uncommon but more frequent in the MAG vs. SAG group in both non-DM (3.3% vs. 2.1%) and DM patients (7.9% vs. 4.8%) (Figure 2). Taggart and colleagues conclude that MAG is associated with substantially lower mortality rates at 10 years after coronary artery bypass grafting in patients with DM. The manuscript is accompanied by an Editorial by Zuzana Motovska from the Charles University and University Hospital Kralovske Vinohrady in Prague, the Czech Republic and Ibrahim Akin from the University of Heidelberg Medical Centre in Mannheim, Germany.17 Motovska and Akin highlight that the results of this post-hoc analysis of 10-year outcomes in patients with diabetes from the ART are hypothesis generating. The relevant evidence for the benefit of MAG vs SAG in diabetic patients should be forthcoming after the Randomization of Single versus Multiple Arterial Grafts trial is completed. If the outcomes are found to be positive, we should expect increased interest and subsequent availability of this modality of coronary bypass grafting. In a Viewpoint article entitled ‘What is the optimal prosthetic valve in dialysis?’, Kevin Kim from McMaster University in Hamilton, Canada, and colleagues note that in patients with end-stage renal disease requiring dialysis, valvular heart disease is diagnosed at a rate 4–5 times higher than in the general population and progresses twice as fast.18 Over 2.6 million people worldwide were receiving dialysis in 2010, and this estimate is expected to increase to >5.4 million people in 2030. Cardiovascular disease is the leading cause of death in dialysis patients; cardiologists and cardiac surgeons should expect to see more patients with end-stage renal disease in the coming decade. Determining the optimal prosthetic valve for dialysis patients with valvular heart disease is complicated. The 2021 ESC/EACTS guidelines for the management of valvular heart disease recommend mechanical valves for dialysis patients when the current evidence does not support recommending a mechanical or biological prosthetic valve. Nonetheless, guidance is required when choosing a prosthesis as multiple factors beyond life expectancy and structural valve deterioration are important to dialysis patients. Current or past guidelines do not discuss these factors with the required nuance. Future guidelines need to discuss the uncertainty in evidence and factors unique to dialysis patients. The issue is also complemented by two Discussion Forum contributions. In a commentary entitled ‘Timing of early invasive strategy in patients with non-ST-elevation acute coronary syndrome’, Amer Aladin from the MedStar Washington Hospital Center in the USA and colleagues comment on the recent publication ‘Timing of invasive strategy in non-ST-elevation acute coronary syndrome: a meta-analysis of randomized controlled trials’ by Thomas Kite from the University of Leicester and University Hospitals of Leicester NHS Trust in the UK.19,20 Kite et al. respond in a separate comment.21 The editors hope that this issue of the European Heart Journal will be of interest to its readers. Dr. Crea reports speaker fees from Amgen, Astra Zeneca, Servier, BMS, other from GlyCardial Diagnostics, outside the submitted work. With thanks to Amelia Meier-Batschelet, Johanna Huggler, and Martin Meyer for help with compilation of this article.