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Background: We aimed to study prospectively the nature and effect of sleep apnea-hypopnea syndrome (SAHS) in patients undergoing coronary artery bypass graft (CABG) surgery over five years of follow-up., Methods: Patients undergoing CABG surgery (N.=145) were assessed longitudinally (baseline, 1 year, and 5 years post-surgery) using the 'STOP-BANG' screen of sleep apnea risk. Additionally, all patients had a preoperative multiple-channel sleep-study, providing acceptable data for an obstructive and central apnea, and desaturation index in 97 patients., Results: Preoperatively, over half (63%) of patients obtained an apnea-hypopnea index score (combining apnea types) in the moderate-severe range for SAHS, and STOP-BANG threshold score (>3/8) was reached by most (95%) patients. Despite some improvement in 'STOP symptoms' at 1-year follow-up, most patients (98%) remained at risk of SAHS at 5 years post-surgery. There was an underlying and chronic relationship between STOP-BANG score and cardiac symptoms at both baseline and 5-year follow-up. Additionally, SAHS variables were associated with greater incidence of acute postoperative events, and generally with increased length of stay on the intensive care unit., Conclusions: We confirm that SAHS is common in CABG-surgery patients, presenting additional clinical challenges and cost implications. The underlying pathophysiology is complex, including upper airway obstruction and cardiorespiratory changes of heart failure. In patients presenting for CABG-surgery, we show chronic susceptibility to SAHS, likely associated with traditional risk factors e.g. obesity but perhaps also with gradual decline in heart function itself. Superimposed on this, there is potential for exacerbated risk of morbidity at the time of CABG surgery itself.

A best evidence topic was constructed according to a structured protocol. The question addressed was whether the configuration of bilateral internal thoracic arteries (BITAs) influences survival, patency or repeat revascularization in patients undergoing coronary artery bypass grafting. Five hundred and seventy-one papers were found using the reported searches, of which 8 represented the best evidence to answer the clinical question. One systematic review, 4 randomized trials and 3 observational studies were selected. The authors, date, journal, study type, population, main outcome measures and results are tabulated. All 4 prospective randomized trials found no significant difference in graft patency or mortality when comparing Y-graft and in situ configurations. Three of the 4 randomized trials found no difference in major adverse cardiovascular and cerebrovascular events or repeat revascularization at follow-up. An exception was Glineur et al. (Bilateral internal thoracic artery configuration for coronary artery bypass surgery: a prospective randomized trial. Circ Cardiovasc Interv 2016;9:7), who found that the Y-configuration resulted in lower rates of major adverse cardiovascular and cerebrovascular events. All 3 observational studies reviewed found no alteration in survival, cardiac events or repeat revascularization between in situ and Y-graft BITA configurations. One systematic review found similar outcomes with respect to mortality, cardiac events and repeat revascularization with in situ and composite BITA. In summary, existing literature demonstrates no difference in clinical outcomes between composite and in situ graft configurations. Furthermore, the configuration of BITA does not affect mortality, graft patency or repeat revascularization.

A best evidence topic was written according to a structured protocol. The question addressed was 'Is it safe to perform coronary angiography (CA) in acute endocarditis?' Three hundred and ninety-seven papers were found using the reported search, of which six represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes, key results and limitations of these papers are tabulated. One of the papers is a case report, which reported a fatal vegetation embolism from an infected aortic valve into the left main coronary artery 14 h after angiography. The remaining five papers are cohort studies. Four of these studies were performed between 1970 and 1980 before the era of echocardiography and were aimed at quantifying the severity of valvular regurgitation. No embolic complications or dislodgement of vegetations occurred in any of the five studies (186 patients). Guidelines published by the European Society of Cardiology (ESC) in 2009 recommended CA in the context of infective endocarditis (IE) for men >40 years old, postmenopausal women, and patients with at least one cardiovascular risk factor or a history of coronary artery disease. Exceptions include patients with large aortic vegetations which may be dislodged during catheterisation, and when emergency surgery is necessary - 1) native aortic or mitral IE with severe acute regurgitation or valve obstruction, or prosthetic valve IE with severe prosthetic dysfunction (dehiscence or obstruction) causing refractory pulmonary oedema or cardiogenic shock; 2) native aortic, mitral, or prosthetic valve IE with fistula into a cardiac chamber or pericardium causing refractory pulmonary oedema or shock. This is reiterated by the guidelines on the management of valvular heart disease published by the ESC in 2007. From the findings of the six papers, it can be concluded that coronary angiography can be performed safely in IE and should be performed if deemed necessary, unless the patients are haemodynamically unstable requiring emergency surgery, or have large vegetations of the aortic valve. This is consistent with the ESC guidelines.

A best evidence topic was written according to a structured protocol. The question addressed was whether incidentally found patent foramen ovale (PFO) during isolated coronary surgery should be closed. A total of 573 papers were found using the reported searches of which six represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. There is currently no evidence to suggest that incidental PFO in patients undergoing cardiac surgery is linked with increased morbidity, mortality or decreased long-term survival. The most significant study identified examined the outcomes of 2277 patients with incidentally found PFO during cardiac surgery of whom 639 underwent closure. After propensity matched analysis, the authors found closure was associated with a significantly higher risk of postoperative stroke with no advantage in terms of long-term survival. A recent survey of 438 cardiac surgeons from the USA showed no consensus on decision-making behind closure, but that factors taken in to account include PFO size, right atrial pressure and a history of paradoxical embolism. This is not surprising given that morphological research has confirmed that larger PFO size is indeed associated with cryptogenic stroke.