Fractional flow reserve

Fractional flow reserve is an index of the physiological significance of a coronary stenosis, defined as the ratio of maximal myocardial blood flow in the presence of the stenosis to the theoretically normal maximal myocardial blood flow (i.e. in the absence of the stenosis). This flow ratio can be calculated from the ratio of distal coronary pressure to central aortic pressure during maximal hyperaemia. More practically, fractional flow reserve indicates to what extent the epicardial segment can be responsible for myocardial ischaemia and, accordingly, fractional flow reserve quantifies the expected perfusion benefit from revascularization by percutaneous coronary intervention. Very limited evidence exists on the role on fractional flow reserve for bypass grafts.

Cardioplegia strategies

There are many cardioplegic strategies for coronary surgery. The goal is a dry operative field while maximizing myocardial recovery. Prospective randomized clinical trials have historically been difficult to achieve because of confounding variables such as solution used, route of administration, temperature, and so forth. This chapter describes an ‘integrated method’ of cardioplegia, so named because it combines many of the salient feature of various methods. It is designed to provide the maximum metabolic support of the myocardium during each phase of the operation. A vast literature from the laboratory to the bedside supports its use. Perhaps most importantly, integrated cardioplegia provides excellent protection of the septum and avoids paradoxical septal motion that may be a form of myocardial injury which is common with other methods of myocardial protection. Any future evaluation of cardioplegia methods should include not only survival but enzyme release and echocardiographic measurements of septal function.

Revascularization using the saphenous vein as a composite graft

The saphenous vein conduit has been used as an aortocoronary bypass graft in almost all previous studies, and its use as a composite graft was reserved for patients with diffusely atherosclerotic or calcified ascending aorta to minimize ascending aorta manipulation and to reduce the risk of neurological injury.

Combined coronary artery bypass grafting and aortic valve replacement

Aortic valve replacement and/or coronary artery bypass grafting (CABG) have become the most common cardiac procedures as the population ages and life expectancy increases. In isolation, both CABG and aortic valve replacement are performed with excellent outcomes throughout the world with operative mortalities of 1–2%. Both procedures have seen significant advances in recent years. The combination of an aortic valve procedure and CABG adds increased complexity and risk, which must be accounted for during operative planning in order to mitigate as much of the increased risk as possible. Improvements in postoperative care, myocardial protection, and operative techniques for combined CABG and aortic valve replacement have resulted in an operative mortality of 0.8–6.4% in recent series.

Preoperative assessment in coronary bypass surgery

Coronary revascularization surgery has become extremely safe over the past 50 years, in terms of absolute mortality. However, in an era where quality of care and recovery are increasingly scrutinized, complications such as stroke, cognitive impairment, prolonged ventilation, renal impairment, wound infection, and even blood transfusion are increasingly important, with rapid recovery to normal function routinely expected by patients, care givers, and healthcare systems alike. These complications are ideally prevented or mitigated preoperatively, with a thorough system of preassessment, targeted evidence-based therapies to reduce morbidity, and careful risk assessment as part of a coherent perioperative approach. This chapter reviews the potential for each of these interventions to improve postoperative outcomes, in addition to an enhanced recovery process, and summarizes them in a schema ready to be introduced into practice.

Patient blood management strategies in cardiac surgery

This chapter discusses patient blood management strategies in cardiac surgery, including sections on the burden of anaemia in cardiac surgery, blood transfusion in cardiac surgery, patient blood management in cardiac surgery (management of anaemia, optimization of haemostasis, autotransfusion techniques, and other supportive measures), and outcomes of patient blood management programmes.

Sequential coronary grafting

Sequential distal grafting is a surgical technique in which a single conduit has two or more distal anastomosis for a single proximal anastomosis; in situ sequential arterial grafts may have no proximal anastomosis. Proponents of this method suggest that there is increased total graft flow due to improved distal run-off in sequential grafts, which leads to better graft patency over time, and that sequential grafting is more efficient in terms of conduit use, and reduces the amount of aortic manipulation during surgery.

Minimal invasive extracorporeal circulation for coronary revascularization surgery

Coronary artery bypass grafting is associated with improved long-term outcome in severe coronary artery disease compared to percutaneous techniques since refinements in surgical technique have reduced morbidity and mortality. Use of cardiopulmonary bypass remains the standard strategy to perform cardiac surgery, which also applies to coronary artery bypass grafting surgery. However, despite major advancements, systemic inflammatory response syndrome and coagulation derangement during conventional cardiopulmonary bypass are still involved in postoperative end-organ injury.

Off-pump coronary artery bypass grafting

Off-pump coronary artery bypass grafting is a highly specialized technique with the potential for reduction of in-hospital morbidity and mortality, particularly in high-risk patient populations. When possible, it should be performed as a clampless or no-aortic-touch technique with multiple or all-arterial conduits. By optimizing longevity of graft patency with arterial conduits and minimizing the risk of perioperative stroke by minimizing aortic manipulation, clampless and no-aortic-touch off-pump coronary artery bypass grafting techniques may be considered the ideal form of surgical coronary revascularization.

Management of cardiopulmonary bypass

Cardiopulmonary bypass provides the surgical team with the most controlled environment to perform the precise anastomoses needed for a successful coronary artery bypass graft operation. It not only promotes the most stable surgical field, but it utilizes a range of techniques that benefit both the surgeon and the patient. This chapter aims to provide the surgical team with an outline of cardiopulmonary bypass circuit components and an overview of common technical issues that diminish the adequacy of perfusion, and to direct the team to resources available in order to achieve evidence-based clinically safe cardiopulmonary bypass.