Coronary Artery Bypass Graft Failure in Women: Incidence and Clinical Implications.

BACKGROUND: Women have worse outcomes after coronary artery bypass surgery (CABG) than men. OBJECTIVES: This study aimed to determine the incidence of CABG graft failure in women, its association with cardiac events, and whether it contributes to sex-related differences in outcomes. METHODS: A pooled analysis of individual patient data from randomized clinical trials with systematic imaging follow-up was performed. Multivariable logistic regression models were used to assess the association of graft failure with myocardial infarction and repeat revascularization between CABG and imaging (primary outcome) and death after imaging (secondary outcome). Mediation analysis was performed to evaluate the effect of graft failure on the association between female sex and risk of death. RESULTS: Seven randomized clinical trials (N = 4,413, 777 women) were included. At a median imaging follow-up of 1.03 years, graft failure was significantly more frequent among women than men (37.3% vs 32.9% at the patient-level and 20.5% vs 15.8% at the graft level; P = 0.02 and P < 0.001, respectively). In women, graft failure was associated with an increased risk of myocardial infarction and repeat revascularization (OR: 3.94; 95% CI: 1.79-8.67) and death (OR: 3.18; 95% CI: 1.73-5.85). Female sex was independently associated with the risk of death (direct effect, HR: 1.84; 95% CI: 1.35-2.50) but the association was not mediated by graft failure (indirect effect, HR: 1.04; 95% CI: 0.86-1.26). CONCLUSIONS: Graft failure is more frequent in women and is associated with adverse cardiac events. The excess mortality risk associated with female sex among CABG patients is not mediated by graft failure.

Wait-times Benchmarks for risk-based prioritization in Transcatheter Aortic Valve Implantation: a simulation study.

BACKGROUND: Demand for transcatheter aortic valve implantation (TAVI) has increased in the last decade, resulting in prolonged wait-times and undesirable health outcomes in many health systems. Risk-based prioritization and wait-times benchmarks can improve equitable access to patients. METHODS: We used simulation models to follow-up a synthetic population of 50,000 individuals from referral to completion of TAVI. Based on their risk of adverse events, patients could be classified as "low-", "medium-" and "high-risk", and shorter wait-times were assigned for the higher risk groups. We assessed the impacts of the size and wait-times for each risk group on waitlist mortality, hospitalization and urgent TAVIs. All scenarios had the same resource constraints, allowing us to explore the trade-offs between faster access for prioritized patients and deferred access for non-prioritized groups. RESULTS: Increasing the proportion of patients categorized as high-risk, and providing more rapid access to the higher-risk groups achieved the greatest reductions in mortality, hospitalizations and urgent TAVIs (relative reductions of up to 29%, 23% and 38%, respectively). However, this occurs at the expense of excessive wait-times in the non-prioritized low-risk group (up to 25 weeks). We propose wait-times of up to 3 weeks for high-risk patients and 7 weeks for medium-risk patients. CONCLUSIONS: Prioritizing higher-risk patients with faster access leads to better health outcomes, however this also results in unacceptably long wait-times for the non-prioritized groups in settings with limited capacity. Decision-makers must be aware of these implications when developing and implementing waitlist prioritization strategies.

Revascularisation in Left Ventricular Systolic Dysfunction: A Meta-analysis of Kaplan-Meier Reconstructed Individual Patient Data.

BACKGROUND: Coronary artery disease is a common cause of ischemic left ventricular systolic dysfunction (LVSD), for which the optimal revascularisation strategy remains unclear. We aimed to determine whether percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) results in greater survival advantage in patients with LVSD. METHODS: Study-level (SLMA) and reconstructed individual patient data (rIPDMA) meta-analyses from Kaplan-Meier (KM) survival curves were performed. A systematic search of Medline, Embase, and Cochrane Library was conducted for observational and randomised studies published after 2010 that compared PCI and CABG in patients with left ventricular ejection fraction ≤ 40%. The primary outcome was all-cause mortality at longest follow-up. The secondary outcomes were myocardial infarction (MI), stroke, repeated revascularisation, cardiovascular mortality, and major adverse cardiovascular and cerebrovascular events (MACCE) at longest follow-up. RESULTS: Fourteen studies (11 observational, 3 randomised, 13,063 patients) were eligible for the SLMA. Seven contained digitisable KM curves from which individual patient data could be reconstructed. Study-level analysis found PCI to be associated with increased all-cause mortality (hazard ratio [HR] 1.41, 95% confidence interval [CI] 1.18-1.69), MI (HR 2.10, 95% CI 1.62-2.72), repeated revascularisation (HR 2.39, 95% CI 1.37-4.17), and MACCE (HR 1.58, 95% CI 1.23-2.03), without significant differences in stroke (HR 0.86, 95% CI 0.39-1.92) or cardiovascular mortality (HR 1.42, 95% CI 0.78-2.59). In the rIPDMA, PCI resulted in increased all-cause mortality (HR 1.57, 95% CI 1.34-1.87) and repeated revascularisation (HR 3.63, 95% CI 3.12-4.21) but overall lower risk of stroke (HR 0.62, 95% CI 0.39-0.99) owing to fewer events during initial follow-up. CONCLUSIONS: In patients with ischemic LVSD, PCI was associated with higher risk of all-cause mortality and repeated revascularisation than CABG, but lower risk of short-term stroke. (PROSPERO: CRD42021291408).

No-touch saphenous vein: current understanding of the conduit 'less handled'.

PURPOSE OF REVIEW: The no-touch technique is an established method to harvest the saphenous vein (NT-SV), which is the most commonly used conduit in coronary artery bypass grafting. Herein, we summarize the foundational evidence, as well as highlight recent innovations and ongoing clinical trials involving NT-SV. RECENT FINDINGS: Through preservation of perivascular tissue for atraumatic handling and omission of manual distension, the NT-SV maintains endothelial nitrous oxide synthase levels and experiences less vascular smooth muscle cell activation, which translates to slower progression of atherosclerosis and less size mismatch of the graft and target vessel. These biomolecular advantages allow NT-SV to provide superior graft patency compared to conventional skeletonized saphenous vein and approximating that of the radial artery. Nonetheless, the clinical benefits of NT-SV for mortality and reduction in major adverse cardiac and cerebrovascular events are insufficiently studied in the long-term. The drawback of NT-SV is the short-term harvest site complications, which may potentially be addressed by the advent of endoscopic no-touch technique. SUMMARY: NT-SV is a promising conduit, and its role will be further clarified in upcoming clinical trials and as follow-up lengthens. However, conduit selection and harvest technique should ultimately be personalized to the individual patient.

Decision analysis in cardiac surgery: a scoping review and methodological primer.

OBJECTIVES: Randomized controlled trials are the gold standard for evidence generation in medicine but are limited by their real-world generalizability, resource needs, shorter follow-up durations and inability to be conducted for all clinical questions. Decision analysis (DA) models may simulate trials and observational studies by using existing data and evidence- and expert-informed assumptions and extend analyses over longer time horizons, different study populations and specific scenarios, helping to translate population outcomes to patient-specific clinical and economic outcomes. Here, we present a scoping review and methodological primer on DA for cardiac surgery research. METHODS: A scoping review was performed using the PubMed/MEDLINE, EMBASE and Web of Science databases for cardiac surgery DA studies published until December 2021. Articles were summarized descriptively to quantify trends and ascertain methodological consistency. RESULTS: A total of 184 articles were identified, among which Markov models (N = 92, 50.0%) were the most commonly used models. The most common outcomes were costs (N = 107, 58.2%), quality-adjusted life-years (N = 96, 52.2%) and incremental cost-effectiveness ratios (N = 89, 48.4%). Most (N = 165, 89.7%) articles applied sensitivity analyses, most frequently in the form of deterministic sensitivity analyses (N = 128, 69.6%). Reporting of guidelines to inform the model development and/or reporting was present in 22.3% of articles. CONCLUSION: DA methods are increasing but remain limited and highly variable in cardiac surgery. A methodological primer is presented and may provide researchers with the foundation to start with or improve DA, as well as provide readers and reviewers with the fundamental concepts to review DA studies.

One-month DAPT with ticagrelor and aspirin for patients undergoing coronary artery bypass grafting: rationale and design of the randomised, multicentre, double-blind, placebo-controlled ODIN trial.

The optimal antiplatelet strategy after coronary artery bypass graft (CABG) surgery in patients with chronic coronary syndromes (CCS) is unclear. Adding the P2Y12 inhibitor, ticagrelor, to low-dose aspirin for 1 year is associated with a reduction in graft failure, particularly saphenous vein grafts, at the expense of an increased risk of clinically important bleeding. As the risk of thrombotic graft failure and ischaemic events is highest early after CABG surgery, a better risk-to-benefit profile may be attained with short-term dual antiplatelet therapy followed by single antiplatelet therapy. The One Month Dual Antiplatelet Therapy With Ticagrelor in Coronary Artery Bypass Graft Patients (ODIN) trial is a prospective, randomised, double-blind, placebo-controlled, international, multicentre study of 700 subjects that will evaluate the effect of short-term dual antiplatelet therapy with ticagrelor plus low-dose aspirin after CABG in patients with CCS. Patients will be randomised 1:1 to ticagrelor 90 mg twice daily or matching placebo, in addition to aspirin 75-150 mg once daily for 1 month; after the first month, antiplatelet therapy will be continued with aspirin alone. The primary endpoint is a hierarchical composite of all-cause death, stroke, myocardial infarction, revascularisation and graft failure at 1 year. The key secondary endpoint is a hierarchical composite of all-cause death, stroke, myocardial infarction, Bleeding Academic Research Consortium (BARC) type 3 bleeding, revascularisation and graft failure at 1 year (net clinical benefit). ODIN will report whether the addition of ticagrelor to low-dose aspirin for 1 month after CABG reduces ischaemic events and provides a net clinical benefit in patients with CCS. (ClinicalTrials.gov: NCT05997693).

Transcatheter Aortic Valve Implantation Wait-Time Management: Derivation and Validation of the Canadian TAVI Triage Tool (CAN3T).

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has seen indication expansion and thus exponential growth in demand over the past decade. In many jurisdictions, the growing demand has outpaced capacity, increasing wait times and preprocedural adverse events. In this study, we derived prediction models that estimate the risk of adverse events on the waitlist and developed a triage tool to identify patients who should be prioritized for TAVI. METHODS AND RESULTS: We included adult patients in Ontario, Canada referred for TAVI and followed up until one of the following events first occurred: death, TAVI procedure, removal from waitlist, or end of the observation period. We used subdistribution hazards models to find significant predictors for each of the following outcomes: (1) all-cause death while on the waitlist; (2) all-cause hospitalization while on the waitlist; (3) receipt of urgent TAVI; and (4) a composite outcome. The median predicted risk at 12 weeks was chosen as a threshold for a maximum acceptable risk while on the waitlist and incorporated in the triage tool to recommend individualized wait times. Of 13 128 patients, 586 died while on the waitlist, and 4343 had at least 1 hospitalization. A total of 6854 TAVIs were completed, of which 1135 were urgent procedures. We were able to create parsimonious models for each outcome that included clinically relevant predictors. CONCLUSIONS: The Canadian TAVI Triage Tool (CAN3T) is a triage tool to assist clinicians in the prioritization of patients who should have timely access to TAVI. We anticipate that the CAN3T will be a valuable tool as it may improve equity in access to care, reduce preventable adverse events, and improve system efficiency.

Do the Few Dictate Care for the Many? Revascularisation Considerations That Go Beyond the Guidelines.

The burden of coronary artery disease (CAD) is large and growing, commonly presenting with comorbidities and older age. Patients may benefit from coronary revascularisation with percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG), yet half of patients with CAD who would benefit from revascularisation fall outside the eligibility criteria of trials to date. As such, the choice of revascularisation procedures varies depending on the CAD anatomy and complexity, surgical risk and comorbidities, the patient's preferences and values, and the treating team's expertise. The recent American guidelines on coronary revascularisation are comprehensive in describing recommendations for PCI, CABG, or conservative management in patients with CAD. However, individual challenging patient presentations cannot be fully captured in guidelines. The aim of this narrative review is to summarise common clinical scenarios that are not sufficiently described by contemporary clinical guidelines and trials in order to inform heart team members and trainees about the nuanced considerations and available evidence to manage such cases. We discuss clinical cases that fall beyond the current guidelines and summarise the relevant evidence evaluating coronary revascularisation for these patients. In addition, we highlight gaps in knowledge based on a lack of research (eg, ineligibility of certain patient populations), underrepresentation in research (eg, underenrollment of female and non-White patients), and the surge in newer minimally invasive and hybrid techniques. We argue that ultimately, evidence-based medicine, patient preference, shared decision making, and effective heart team communications are necessary to best manage complex CAD presentations potentially benefitting from revascularisation with CABG or PCI.

Outcomes following coronary artery bypass grafting with multiple arterial grafting by pump status in men and women.

BACKGROUND: Multiple arterial grafting (MAG) and off-pump surgery are strategies proposed to improve outcomes with coronary artery bypass grafting (CABG). This study was conducted to determine the impact of off-pump surgery on outcomes after CABG with MAG in men and women. METHODS: This cohort study used population-based data to identify all Ontarians undergoing isolated CABG with MAG between October 2008 and September 2019. The primary outcome was all-cause mortality. Secondary outcomes included major adverse cardiac and cerebrovascular events (MACCE; hospitalization for stroke, myocardial infarction hospitalization or heart failure, or repeat revascularization). Analysis used propensity-score overlap-weighted cause-specific Cox proportional hazard regression. RESULTS: A total of 2989 women (1188 off-pump, 1801 on-pump) and 16,209 men (6065 off-pump, 10,144 on-pump) underwent MAG with a median follow-up of 5.0 years (interquartile range, 2.7-8.0) years. Compared to the on-pump approach, all-cause mortality was not changed with off-pump status (hazard ratio [HR] in women: 1.25 [95% CI, 0.83-1.88]; in men: 1.08 [95% CI, 0.85-1.37]). In women, the risk of MACCE was significantly higher off-pump (HR, 1.45; 95% CI, 1.04-2.03), with nonsignificantly increased risk observed for all component outcomes. CONCLUSIONS: In patients undergoing CABG with MAG, this population-based analysis found no association between pump status and survival in either men or women. However, it did suggest that off-pump MAG in women may be associated with an increased risk of MACCE.

Race and Ethnicity in Cardiac Surgery: A Missed Opportunity?

BACKGROUND: Patients' race and/or ethnicity are increasingly being associated with differential surgical access and outcomes in cardiac surgery. However, deriving evidence-based conclusions that can inform surgical care has been difficult because of poor diversity in study populations and conflicting research methodology and findings. Using a fictional patient example, this review identifies areas of concern in research engagement, methodology, and analyses, as well as potential steps to improve race and ethnicity considerations in cardiac surgical research. METHODS: A narrative literature review was performed using the PubMed/MEDLINE and Google Scholar databases, with a combination of cardiac surgery, race, ethnicity, and disparities keywords. RESULTS: Less than half of the published cardiac surgery randomized control trials report the race and/or ethnicity of research participants. Racial and/or ethnic minorities make up <20% of most study populations and are significantly underrepresented relative to their proportions of the general population. Further, race and/or ethnicity of research participants is variably categorized based on ancestry, geographic regions, cultural similarities, or minority status. There is growing consideration of analyzing interrelated and confounding variables, such as socioeconomic status, geographic location, or hospital quality, to better elucidate racial and/or ethnic disparities; however, intersectionality considerations remain limited in cardiac surgery research. CONCLUSIONS: Racial and/or ethnic disparities are increasingly being reported in research engagement, cardiac pathologies, and surgical outcomes. To promote equitable surgical care, tangible efforts are needed to recruit racially and/or ethnically minoritized patients to research studies, be transparent and consistent in their groupings, and elucidate the impact of their intersectional social identities.

Research Concepts and Opportunities for Early-Career Investigators in Cardiac Surgery.

Basic, translational or clinic, research is a key component of cardiac surgery. Understanding basic cellular and molecular mechanisms is key to improving patient outcomes, and cardiac surgical procedures must be compared with nonsurgical alternatives. However, guidance for early-career investigators interested in cardiac surgery research is limited. This opinion piece aims at providing basic guidance and principles based on the authors' experience.

The Call for the "Interventional/Hybrid" Aortic Surgeon: Open, Endovascular, and Hybrid Therapies of the Aortic Arch.

Aortic arch pathology is relatively rare but potentially highly fatal and associated with considerable comorbidity. Operative mortality and complication rates have improved over time but remain high. In response, aortic arch surgery is one of the most rapidly evolving areas of cardiac surgery in terms of surgical volume and improved outcomes. Moreover, there has been a surge in novel devices and techniques, many of which have been developed by or codeveloped with vascular surgeons and interventional radiologists. Nevertheless, the extent of arch surgery, the choice of nadir temperature, cannulation, and perfusion strategies, and the use of open, endovascular, or hybrid options vary according to country, centre, and surgeon. In this review article, we provide a technical overview of the surgical, total endovascular, and hybrid repair options for aortic arch pathology through historical developments and contemporary results. We highlight key information for surgeons, cardiologists, and trainees to understand the management of patients with aortic arch pathology. We conclude by discussing training paradigms, the role of aortic teams, and gaps in knowledge, arguing for the need for wire skills for the future "interventional aortic surgeon" and increased research into techniques and novel devices to continue improving outcomes for aortic arch surgery.

Cusp overlap method for self-expanding transcatheter aortic valve replacement.

BACKGROUND: Conduction disturbances and the need for permanent pacemaker (PPM) implantation remains a common complication for transcatheter aortic valve replacement (TAVR), particularly when self-expanding (SE) valves are used. AIMS: We compared in-hospital and 30-day rates of new PPM implantation between patients undergoing TAVR with SE valves using the conventional three-cusp coplanar implantation technique and the cusp-overlap technique. METHODS: We retrospectively compared patients without a pre-existing PPM who underwent a TAVR procedure with SE Evolut R or PRO valves using the cusp-overlap technique from July 2018 to September 2020 (n = 519) to patients who underwent TAVR using standard three-cusp technique from April 2016 to March 2017 (n = 128) in two high volume Canadian centers. RESULTS: There was no significant difference in baseline RBBB between the groups (10.4% vs. 13.2; p = 0.35). The rate of in-hospital new complete heart block (9.4% vs. 23.4%; p ≤ 0.001) and PPM implantation (8% vs. 21%; p ≤ 0.001) were significantly reduced when using the cusp-overlap technique. The incidence of new LBBB (30.4% vs. 29%; p = 0.73) was similar. At 30 days, the rates of new complete heart block (11% vs. 23%; p ≤ 0.001) and PPM implantation (10% vs. 21%, p ≤ 0.001) remained significantly lower in the cusp-overlap group, while the rate of new LBBB (35% vs. 30%; p = 0.73) was similar. CONCLUSION: Cusp-overlap approach offers several potential technical advantages compared to standard three-cusp view, and may result in lower PPM rates in TAVR with SE Evolut valve.

Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology 2023 Focused Update of the Guidelines for the Use of Antiplatelet Therapy.

Antiplatelet therapy (APT) is the foundation of treatment and prevention of atherothrombotic events in patients with atherosclerotic cardiovascular disease. Selecting the optimal APT strategies to reduce major adverse cardiovascular events, while balancing bleeding risk, requires ongoing review of clinical trials. Appended, the focused update of the Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology guidelines for the use of APT provides recommendations on the following topics: (1) use of acetylsalicylic acid in primary prevention of atherosclerotic cardiovascular disease; (2) dual APT (DAPT) duration after percutaneous coronary intervention (PCI) in patients at high bleeding risk; (3) potent DAPT (P2Y12 inhibitor) choice in patients who present with an acute coronary syndrome (ACS) and possible DAPT de-escalation strategies after PCI; (4) choice and duration of DAPT in ACS patients who are medically treated without revascularization; (5) pretreatment with DAPT (P2Y12 inhibitor) before elective or nonelective coronary angiography; (6) perioperative and longer-term APT management in patients who require coronary artery bypass grafting surgery; and (7) use of APT in patients with atrial fibrillation who require oral anticoagulation after PCI or medically managed ACS. These recommendations are all on the basis of systematic reviews and meta-analyses conducted as part of the development of these guidelines, provided in the Supplementary Material.

Revascularization strategies for multivessel coronary artery disease based on sex and age.

OBJECTIVES: This study describes coronary revascularization strategies used by sex and age in the USA. METHODS: A sex-stratified cohort study from the National Inpatient Sample from the Agency for Healthcare Research and Quality (USA) including patients admitted for coronary revascularization with primary or secondary diagnoses of chronic coronary syndrome or non-ST elevation myocardial infarction who underwent ≥3-vessel coronary artery bypass grafting or percutaneous coronary intervention from January 2019 to December 2020. The primary outcome was the use rate of coronary artery bypass grafting or multivessel percutaneous coronary intervention. Prespecified subgroups included age and non-ST elevation myocardial infarction. RESULTS: Among 121 150 patients (21.7% women), there were no sex differences in age (women: 66.6 [66.5-66.7], men: 67.6 [67.5-67.7], standardized mean difference: 0.1) or non-ST elevation myocardial infarction incidence (women: 37.4%, men: 45.7%, standardized mean difference: 0.17). The majority of women (74.2%) and men (84.9%) underwent bypass grafting, which was unaffected by age, race or non-ST elevation myocardial infarction. Women were less likely to undergo bypass grafting than percutaneous intervention (adjusted odds ratio 0.49, 95% confidence interval 0.44-0.54; P < 0.001) and a disparity most pronounced in patients >80 years old (adjusted odds ratio 0.31, 95% confidence interval 0.22-0.45; P < 0.001). CONCLUSIONS: Most patients with multivessel coronary artery disease needing revascularization undergo bypass grafting, irrespective of sex, age or clinical presentation. The sex disparity in the use of bypass grafting is mostly seen among patients >80 years old.