Defining the Role of Anaortic Coronary Artery Bypass Grafting.

As the population ages and co-morbidities become more prevalent, the complexity of patients presenting for coronary artery bypass surgery is increasing. Cardiopulmonary bypass and aortic cross-clamping in these patients carry increased risk and, indeed, in some patients, with ascending aortic disease, the risks are prohibitive. Total-arterial anaortic coronary artery surgery is a technique that provides complete surgical coronary artery revascularization without cardiopulmonary bypass and without manipulating the ascending aorta. The technique essentially eliminates the risk of cerebral embolization of aortic atheroma and aortic injury. Anaortic techniques are an essential skillset for coronary artery surgery centers treating higher-risk patients.

A case report of truncus arteriosus with intact ventricular septum and crossed branch pulmonary arteries.

Background: Truncus arteriosus (TA) or persistent arterial trunk describes the presence of a solitary arterial trunk arising from the base of the heart, supported by a common ventriculoarterial junction. The trunk gives rise to the coronary arteries, systemic arteries, and at least one pulmonary artery. Truncus arteriosus is a rare congenital cardiac disease, and even rarer is the absence of ventricular septal defect. Case summary: We report a case of a 2-day-old infant who presented with cyanosis and a cardiac murmur. He was diagnosed with TA with intact ventricular septum (IVS), as well as crossed pulmonary arteries which was identified on pre-operative imaging. We describe the surgical management and short-term follow-up. Discussion: Our clinical case demonstrates a unique diagnosis and management of TA with IVS identified by pre-operative imaging with good surgical outcome.

Synchronous Carotid Endarterectomy and Anaortic Off-Pump Coronary Artery Bypass Surgery.

BACKGROUND: There is ongoing debate regarding the optimal strategy and timing for the surgical management of patients with severe concomitant carotid and coronary artery disease. Anaortic off-pump coronary artery bypass (anOPCAB), which avoids aortic manipulation and cardiopulmonary bypass, has been shown to reduce the risk of perioperative stroke. We present the outcomes of a series of synchronous carotid endarterectomy (CEA) and anOPCAB. METHODS: A retrospective review was performed. The primary endpoint was stroke at 30 days post-operation. Secondary endpoints included transient ischaemic attack, myocardial infarction and mortality 30 days post-operation. RESULTS: From 2009 to 2016, 1,041 patients underwent anOPCAB with a 30-day stroke rate of 0.4%. The majority of patients had preoperative carotid-subclavian duplex ultrasound screening and 39 were identified with significant concomitant carotid disease who underwent synchronous CEA-anOPCAB. The mean age was 71±7.5 years. Nine patients (23.1%) had previous neurological events. Thirty (30) patients (76.9%) underwent an urgent operation. For CEA, a conventional longitudinal carotid endarterectomy with patch angioplasty was performed in all patients. For anOPCAB, total arterial revascularisation rate was performed in 84.6% and the mean number of distal anastomoses was 2.9±0.7. In the 30-day postoperative period, there was one stroke (2.63%), two deaths (5.26%), two transient ischaemic attacks (TIAs) (5.26%) and no myocardial infarction. Two patients experienced acute kidney injury (5.26%), one of which required haemodialysis (2.63%). Mean length of stay was 11.37±7.9 days. CONCLUSION: Synchronous CEA and anOPCAB is a safe and effective option for patients' severe concomitant disease. Preoperative carotid-subclavian ultrasound screening allows identification of these patients.

Selecting the optimal treatment for left main coronary disease: The importance of identifying subgroups of patients.

Randomized trials of stenting versus surgery for patients with unprotected left main (LM) coronary stenosis have largely shown similar survival between the two interventions. However, patients with LM stenosis represent a heterogeneous group in which subgroups likely to benefit from one therapy more than another are difficult to identify. Increasing coronary disease burden is the most accepted subgrouping for identifying optimal therapy but this can be defined in more detail allowing greater discrimination. Competitive flow reduces bypass graft patency in patients with isolated LM stenosis and complex bifurcation stenoses reduce the effectiveness of coronary stenting. The evidence for LM stenosis subgroupings is presented.

Atrial fibrillation management during septal myectomy for hypertrophic cardiomyopathy: A systematic review.

INTRODUCTION: Atrial fibrillation is common in patients with hypertrophic cardiomyopathy, and significantly impacts mortality and morbidity. In patients with atrial fibrillation undergoing septal myectomy, concomitant surgery for atrial fibrillation may improve outcomes. METHODS: A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All studies reporting the outcomes of combined septal myectomy and atrial fibrillation surgery were included. RESULTS: A total of 10 observational studies were identified, including 644 patients. Most patients had paroxysmal atrial fibrillation. The proportion with prior unsuccessful ablation ranged from 0 to 19%, and preoperative left atrial diameter ranged from 44 ± 17 to 52 ± 8 mm. Cox-Maze IV (n = 311) was the most common technique used, followed by pulmonary vein isolation (n = 222) and Cox-Maze III (n = 98). Patients with persistent or longstanding atrial fibrillation more frequently received Cox-Maze III/IV. Ranges of early postoperative outcomes included: mortality 0 to 7%, recurrence of atrial tachyarrhythmias 4.4 to 48%, cerebrovascular events 0 to 1.5%, and pacemaker insertion 3 to 21%. Long-term data was limited. Freedom from atrial tachyarrhythmias at 1 year ranged from 74% to 96%, and at 5 years from 52% to 100%. Preoperative predictors of late atrial tachyarrhythmia recurrence included left atrial diameter >45 mm, persistent or longstanding preoperative atrial fibrillation and longer atrial fibrillation duration. CONCLUSION: In patients with atrial fibrillation undergoing septal myectomy, the addition of ablation surgery adds low overall risk to the procedure, and likely reduces the risk of recurrent atrial fibrillation in the long term. Future randomised studies comparing septal myectomy with or without concomitant AF ablation are needed.

Transcatheter Aortic Valve Implantation (TAVI) Versus Surgical Aortic Valve Replacement for Aortic Stenosis (SAVR): A Cost-Comparison Study.

BACKGROUND: Comparative costing studies using real-world data stratified by patient case-mix, are valuable to decision makers for making reimbursement decisions of new interventions. This study evaluated real-world hospital admissions and short-term costs of transcatheter aortic valve implantation (TAVI) and isolated surgical aortic valve replacement (SAVR) for patients with aortic stenosis, stratified by the Society of Thoracic Surgeons (STS) risk scores. METHODS: Retrospective analysis of consecutive patients with a principal diagnosis of aortic stenosis who underwent isolated valve replacement at a single tertiary hospital, January 2012-December 2017. Patients were followed-up for 30 days post-procedure or until hospital discharge if index hospitalisation was greater than 30 days. Intensive care unit (ICU) and hospital length of stay (days), and costs in 2018 Australian dollars for the index procedure and 30-day follow-up were assessed. Multivariable generalised linear and two-part models with gamma distribution and log link function adjusting for Society of Thoracic Surgeons (STS) risk group and key sociodemographic characteristics were used. RESULTS: Of 488 patients, 61% males, median age 78 years (IQR 14 years), 221 (45%) received transcatheter aortic valve replacement (TAVI) and 267 (55%) received surgical aortic valve replacement (SAVR). STS risk scores were low (28%), intermediate (46%) and high (26%) for TAVI patients, and low (85%), intermediate (12%) and high (3%) for SAVR patients. When adjusted, TAVI length of stay was 57% shorter than SAVR (95% CI 31-83%, p<0.001) for intensive care unit (ICU) admission, and 64% shorter (95% CI 47-81%, p<0.001) for hospital admissions. TAVI costs were 13% lower than SAVR (95% CI 4-22%, p=0.005). CONCLUSION: This data suggests short-term health care costs are lower for patients with aortic stenosis undergoing TAVI than SAVR. A further roll-out of the TAVI program in hospitals across Australia may result in savings to the health system.

Five-Year Survival of Transcatheter Aortic Valve Implantation in High-Risk Patients.

BACKGROUND: Although transcatheter aortic valve implantation (TAVI) has become the standard treatment for severe aortic stenosis in high-risk patients in Australia, there is still limited data on long term survival. METHODS: All patients undergoing TAVI at a single tertiary institution between September 2009 and December 2015 were included. The primary outcome was survival, by linkage of patients with the National Death Index of the Australian Institute of Health and Welfare. Post-procedure data and echocardiographic measurements were retrospectively analysed for all patients. RESULTS: A total of 186 patients were included. It was a high-risk patient population (mean EuroSCORE 31.5±20.5, mean age 83.0±8.2 years). Valve prostheses used were Edwards SAPIEN (ES) (Edwards, Irvine, CA, USA) in 16.1%, Edwards SAPIEN XT (ESXT) in 74.2%, and Medtronic CoreValve (MCV) (Medtronic, Minneapolis, MN, USA) in 9.7%. Median survival time for the entire cohort was 68.2 months (95% Confidence Interval [CI]; Lower Limit [LL] 58.0 months, Upper Limit [UL] not defined). The 2- and 5-year estimates of survival were 85% (LL 80%, UL 90%) and 56% (LL 48%, UL 66%), respectively. There was no statistically significant difference in median survival between the ES and ESXT valves, or implantation approach. Survival was greater in patients with creatinine <200 µmol/L compared to >200 µmol/L (68.8 months [LL 61.4, UL n/a] vs 48.0 months [LL 25.5, UL n/a]). Over the study period, there was a statistically significant trend in increasing mean transvalvular gradient (ES: 1.66 mmHg/yr, p=0.0058; ESXT: 2.50 mmHg/yr, p≤0.001) and maximum velocity (ESXT: 0.16 m/s/yr, p=0.004) and decreasing valve area (ESXT: -0.07 cm2/yr, p<0.001). There was substantial attrition of patient echocardiographic follow-up (number of echocardiograms followed up at 5 years=6, number at risk=41). CONCLUSIONS: This study has demonstrated acceptable survival in a high-risk cohort of patients undergoing TAVI, with comparable results to larger international experiences. There was a trend for worsening haemodynamics that needs to be monitored. Future studies need to examine patient quality of life and the performance of newer generation prostheses.

Toward stroke-free coronary surgery: The role of the anaortic off-pump bypass technique.

Surgical coronary revascularization remains the preferred strategy in a significant portion of patients with coronary artery disease due to superior long-term outcomes. However, there is a significant risk of perioperative neurologic injury that has influenced guideline recommendations. These complications occur in 1%-5% of patients, ranging from overt neurologic deficits with permanent disability, to subtle cerebral defects noted on neuroimaging that may result in slow cognitive and functional decline. The primary mechanism by which these events occur is thromboembolism from manipulation of the ascending aorta. This occurs during cardiopulmonary bypass, aortic cross-clamping, and partial occlusion clamping (side clamp). Elderly patients and patients with aortic atheroma are, therefore, at significantly increased risk. Initial surgical techniques addressed this by aggressively debriding or replacing the ascending aorta during coronary artery bypass grafting (CABG). Strategies then moved toward minimizing aortic manipulation through pump-assisted beating heart surgery and off-pump surgery with partial occlusion clamping or proximal anastomosis devices. Finally, anaortic off-pump CABG aims to avoid all manipulation of the ascending aorta through advanced off-pump grafting techniques combined with in situ and composite grafts. This has been demonstrated to result in the greatest reduction in risk. Establishing successful anaortic off-pump CABG programs requires subspecialization and focused interest groups dedicated to advancing CABG outcomes.

Rugby Player's Aorta: Alarming Prevalence of Ascending Aortic Dilatation and Effacement in Elite Rugby Players.

BACKGROUND: Prompted by a cluster of observations concerning ascending aortic pathology in elite rugby players, we assessed over 150 asymptomatic predominantly retired players with echocardiography, aiming to document the prevalence and severity of ascending aortic dilatation and/or anterior aortic effacement, both 'risk factors' for potentially catastrophic aortic complications. METHODS: Rugby players (at least 5 years of high level competitive rugby) were classified as elite (national, state or first grade representatives) or non-elite. A total of 152 asymptomatic players with a mean age of 45 ± 13 years (range 21-65) underwent transthoracic echocardiography. Z-scores (number of standard deviations from a population mean) were calculated for aortic root and ascending aortic size. RESULTS: Regarding the aortic root, a Z-score of >2 was seen in 24% (expected prevalence 2.3%, p < 0.001) and a Z-score >3 was seen in 4% (expected prevalence 0..1%, p < 0.001). Sixty-two (62) players (41%) had an aortic root greater than 40 mm diameter. Ascending aortic Z-scores were >2 in 53% of players and >3 in 22% (p < 0.001). Abnormal anterior aortic effacement at the sinotubular junction (STJ) was seen in 88 players (58%). Abnormal aortic dilatation and effacement were associated with a longer duration of competitive rugby participation and elite status, respectively. CONCLUSIONS: Ascending aortic dilatation with abnormal anterior effacement is exceedingly common in asymptomatic retired elite rugby players. This warrants increased surveillance in retired players until the clinical significance of these findings can be further investigated.

Repair of Less Than Severe Tricuspid Regurgitation During Left-Sided Valve Surgery: A Meta-Analysis.

BACKGROUND: This systematic review and meta-analysis was undertaken to investigate the short- and long-term clinical outcomes of concurrent repair of mild or moderate tricuspid regurgitation (TR) during left-sided valve surgery. METHODS: Medline, PubMed, EMBASE, and Cochrane Libraries were searched, and 12 studies were identified, comprising 1373 patients who underwent TR repair during left-sided valve surgery and 1553 patients who did not. Of these studies, 6 were classified as having a low risk of bias (randomized controlled trials or propensity-matched studies), and 6 were considered as having a high risk of bias (nonmatched observational studies). The primary analysis included only studies with a low risk of bias (399 repair and 426 nonrepair). RESULTS: Primary analysis of studies at low risk of bias demonstrated that the addition of TR repair compared with nonrepair was associated with reduced risks of cardiovascular mortality, all-cause mortality, and progression of TR over a median of 5.3 years of follow-up (cardiovascular mortality: relative risk [RR], 0.46; 95% confidence interval [CI], 0.28 to 0.75; P = .002; all-cause mortality: RR, 0.68; 95% CI, 0.49 to 0.96; P = .03; and TR progression: RR, 0.26; 95% CI, 0.12 to 0.56; P < .001). Cardiopulmonary bypass time was significantly shorter in the nonrepair group (mean weighted difference, 18 minutes; 95% CI, 6 to 30; P = .003), although the risk of perioperative mortality was comparable between the 2 groups (RR, 0.72; 95% CI, 0.27 to 1.97; P > .05). CONCLUSIONS: Concurrent repair of mild or moderate TR during left-sided valve surgery is associated with improved long-term clinical outcomes without adversely affecting early survival. Should these results be validated by ongoing trials, there should be a revision of current guidelines to recommend a more aggressive approach toward TR repair.

Extracorporeal membrane oxygenation support in refractory perioperative anaphylactic shock to rocuronium: a report of two cases.

In recent years, extracorporeal membrane oxygenation has become increasingly common in the treatment of in-hospital cardiac arrest in non-cardiac surgery patients. This includes cardiac arrest secondary to perioperative anaphylactic shock refractory to standard advanced life support protocols, which is a rare but catastrophic event associated with significant mortality. Neuromuscular blocking drugs are most commonly implicated in perioperative anaphylaxis, with rocuronium playing a major role. In this article, we report two cases of young and otherwise fit and well patients who experienced a perioperative arrest secondary to rocuronium anaphylaxis before elective surgery; both patients did not respond to conventional advanced life support, but survived neurologically intact after institution of urgent veno-arterial extracorporeal membrane oxygenation.

Addressing the ethical grey zone in surgery: a framework for identification and safe introduction of novel surgical techniques and procedures.

While the introduction of new surgical techniques can radically improve patient care, they may equally expose patients to unforeseen harms associated with untested procedures. The enthusiastic uptake of laparoscopic cholecystectomy in the early 1990s saw a dramatic increase in the rate of common bile duct injuries, and was described by Alfred Cuschieri as 'the biggest unaudited free-for-all in the history of surgery' due to 'a lack of effective centralised control'. Whether a new surgical intervention is considered an acceptable 'minor' variation of an established procedure, or is sufficiently 'novel' to constitute experimentation on human subjects is often unclear. Furthermore, once a new technique is identified as experimental, there is no agreed protocol for safety evaluation in a first-in-human setting. In phase I (first-in-human) pharmacological trials only small, single arm cohorts of highly selected patients are enrolled in order to establish the safety profile of a new drug. This exposes only a small number of patients to the unknown or unforeseen risks that may be associated with a new agent, in a highly regulated and scientifically rigorous manner. There is no equivalent study design for the introduction of new and experimental surgical procedures. This article proposes a practical stepwise approach to the safe introduction of new surgical procedures that surgeons and surgical departments can adopt. It includes criteria for new surgical techniques which require formal prospective ethical evaluation, and a novel study design for conducting a safety evaluation at the 'first in human' stage.

Bilateral Versus Single Internal Mammary Artery Use in Coronary Artery Bypass Grafting: A Propensity Matched Analysis.

BACKGROUND: Bilateral internal mammary artery (BIMA) grafts have demonstrated superior long-term outcomes compared with single internal mammary artery (SIMA) grafts. Despite this, BIMA remains widely underutilised due to perceived technical challenges and concerns regarding wound healing. We sought to examine the morbidity and mortality associated with BIMA use in a propensity-matched cohort of patients. METHODS: From 2009 to 2016, 3,594 consecutive patients underwent coronary artery bypass surgery at three affiliated institutions. Thirty-day (30) mortality and morbidity data were collected prospectively. Propensity-score matched analyses were performed for BIMA versus SIMA use controlling for a number of preoperative characteristics. RESULTS: Overall, 29% of procedures were performed off pump, with a greater proportion in the BIMA group (43% vs. 21%, p<0.001). In the propensity-score analysis consisting of 820 matched pairs, there were similar rates of 30-day mortality (1.3% BIMA vs. 0.9% SIMA, p=0.48) and deep sternal wound infection (1.1% BIMA vs. 0.9% SIMA, p=0.84). The rate of superficial sternal wound infection trended towards being higher in the BIMA group (2.6% vs. 1.3%, p=0.077). The rates of red blood cell transfusions (27.4% vs. 27%, p=0.217), other blood product transfusions (18% vs. 20%, p=0.217), and reoperation for bleeding (2.9% vs. 2.1%, p=0.349) were similar. CONCLUSIONS: Bilateral internal mammary artery use was associated with similar rates of deep sternal wound infection compared to SIMA use, with a preponderance of superficial sternal wound infections that did not result in increased mortality or transfusion requirements. The use of BIMA should be more widely considered for coronary artery bypass surgery.

Dual inflow, total-arterial, anaortic, off-pump coronary artery bypass grafting: how to do it.

Coronary surgery performed on an arrested heart, using one internal mammary artery and a saphenous vein carries two main potential drawbacks: the known failure rate of vein grafts and the relatively high rate of neurologic injury. To address these concerns, we describe a technique that achieves complete revascularization without manipulating the ascending aorta (anaortic, off-pump) and utilizing total arterial grafts. All patients undergo thorough preoperative investigation, including bilateral carotid, vertebral and subclavian artery Duplex ultrasounds. A pulmonary artery catheter, transoesophageal echocardiography, and point-of-care coagulation testing are used in each case. The left and right internal mammary arteries and non-dominant radial artery are harvested using a fully skeletonised technique. Wide bilateral extrapleural retrothymic tunnels are developed and the pericardium is opened widely to facilitate cardiac positioning. A tandem graft is constructed with the right internal mammary artery (RIMA) in situ and radial artery using an end-to-end anastomosis. This graft is brought into the pericardium and through the transverse sinus in order to graft the lateral and inferior walls with multiple sequential distal anastomoses. The left internal mammary artery (LIMA) in situ is used to graft the anterior wall. Four main cardiac positions (high and low lateral walls, inferior and anterior walls) are obtained using a combination of off-pump stabilizer positioning, alternate tension on pericardial 'heart-strings', table tilting and folded wet sponges. All distal anastomoses are performed using silastic intracoronary shunts and an off-pump myocardial stabilizer. All grafts are checked using transit-flow time measurements. Milrinone is continued overnight and dual antiplatelet therapy is continued for 3 months postoperatively.