The American Association for Thoracic Surgery and The Society of Thoracic Surgeons Reasoning for Not Endorsing the 2021 ACC/AHA/SCAI Coronary Revascularization Guidelines

Myocardial ischaemic syndromes: a new nomenclature to harmonize evolving international clinical practice guidelines

Since the 1960s, cardiologists have adopted several binary classification systems for acute myocardial infarction (MI) that facilitated improved patient management. Conversely, for chronic stable manifestations of myocardial ischaemia, various classifications have emerged over time, often with conflicting terminology-e.g. 'stable coronary artery disease' (CAD), 'stable ischaemic heart disease', and 'chronic coronary syndromes' (CCS). While the 2019 European guidelines introduced CCS to impart symmetry with 'acute coronary syndromes' (ACS), the 2023 American guidelines endorsed the alternative term 'chronic coronary disease'. An unintended consequence of these competing classifications is perpetuation of the restrictive terms 'coronary' and 'disease', often connoting only a singular obstructive CAD mechanism. It is now important to advance a more broadly inclusive terminology for both obstructive and non-obstructive causes of angina and myocardial ischaemia that fosters conceptual clarity and unifies dyssynchronous nomenclatures across guidelines. We, therefore, propose a new binary classification of 'acute myocardial ischaemic syndromes' and 'non-acute myocardial ischaemic syndromes', which comprises both obstructive epicardial and non-obstructive pathogenetic mechanisms, including microvascular dysfunction, vasospastic disorders, and non-coronary causes. We herein retain accepted categories of ACS, ST-segment elevation MI, and non-ST-segment elevation MI, as important subsets for which revascularization is of proven clinical benefit, as well as new terms like ischaemia and MI with non-obstructive coronary arteries. Overall, such a more encompassing nomenclature better aligns, unifies, and harmonizes different pathophysiologic causes of myocardial ischaemia and should result in more refined diagnostic and therapeutic approaches targeted to the multiple pathobiological precipitants of angina pectoris, ischaemia and infarction.

Clinical and financial outcomes associated with the utilization of right internal mammary artery versus radial artery in multivessel coronary artery bypass grafting

BACKGROUND

Multi-arterial coronary bypass grafting with the left internal mammary artery as a conduit has been shown to offer superior long-term survival compared to single-arterial coronary bypass grafting. Nevertheless, the selection of a secondary conduit between the right internal mammary artery and the radial artery remains controversial. Using a national cohort, we examined the relationships between the right internal mammary artery and the radial artery with acute clinical and financial outcomes.

METHODS

Adults undergoing on-pump multivessel coronary bypass grafting with left internal mammary artery as the first arterial conduit were identified in the 2016 to 2020 Nationwide Readmissions Database. Patients receiving either the right internal mammary artery or the radial artery, but not both, were included in the analysis. Multivariable regression models were fitted to examine the association between the conduits and in-hospital mortality, as well as additional secondary outcomes.

RESULTS

Of an estimated 49,798 patients undergoing multi-arterial coronary bypass grafting, 29,729 (59.7%) comprised the radial artery cohort. During the study period, the proportion of multi-arterial coronary bypass grafting utilizing the radial artery increased from 51.3% to 65.2% (nptrend <0.001). Following adjustment, the radial artery was associated with reduced odds of in-hospital mortality (adjusted odds ratio 0.44), prolonged mechanical ventilation (adjusted odds ratio 0.78), infectious complications (adjusted odds ratio 0.69), and 30-day nonelective readmission (adjusted odds ratio 0.77, all P < .05).

CONCLUSION

Despite no definite endorsement from surgical societies, the radial artery is increasingly utilized as a secondary conduit in multi-arterial coronary bypass grafting. Compared to the right internal mammary artery, the radial artery was associated with lower odds of in-hospital mortality, complications, and reduced healthcare expenditures. These results suggest that whenever feasible, the radial artery should be the favored conduit over the right internal mammary artery. Nevertheless, future studies examining long-term outcomes associated with these vessels remain necessary.

Coronary surgery provides better survival than drug-eluting stent: A pooled meta-analysis of Kaplan-Meier-derived individual patient data

OBJECTIVES

We explored the current evidence on coronary disease treatment comparing the survival of 2 therapeutic strategies: coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) with drug-eluting stent (DES).

METHODS

PubMed, Embase, and Google Scholar were searched for randomized clinical trials comparing CABG versus PCI with DES. The end point was overall mortality. Two statistical approaches were used: the generic inverse variance method, which was used to pool the incident rate ratios, and the pooled meta-analysis of Kaplan-Meier-derived individual patient data.

RESULTS

Eight randomized clinical trials comparing 4975 patients undergoing CABG and 4992 patients undergoing PCI were included in our meta-analysis. Generic inverse variance method showed a statistically significant survival benefit of the CABG group (incident rate ratio, 1.21; 95% confidence interval, 1.09-1.35; P < .01). The Kaplan-Meier estimates of survival at 1, 5, and 10 years of the CABG group were 97.1%, 90.3%, and 80.3%, respectively. The Kaplan-Meier estimates of survival at 1, 5, and 10 years of the PCI group were 97.0%, 87.7%, and 76.4%, respectively. The log-rank analysis confirmed a statistically significant benefit in term of overall mortality of the CABG group (hazard ratio, 1.24; 95% confidence interval, 1.11-1.38; P = .0001).

CONCLUSIONS

The present meta-analysis suggests that CABG provides a consistent survival benefit over PCI with DES.

Contemporary Coronary Artery Bypass Grafting vs Multivessel Percutaneous Coronary Intervention

BACKGROUND

Interpretation of recent alterations to the guideline priority of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for multivessel disease contests historical data and practice. To reevaluate contemporary outcomes, a large contemporary analysis was conducted comparing CABG with multivessel PCI among Medicare beneficiaries.

METHODS

The United States Centers for Medicare and Medicaid Services database was evaluated all beneficiaries with acute coronary syndrome undergoing isolated CABG or multivessel PCI (2018-2020). Risk adjustment was performed using multilevel regression analysis, Cox proportional hazards time to event models, and inverse probability of treatment weighting propensity scores.

RESULTS

A total of 104,127 beneficiaries were identified undergoing CABG (n = 51,389) or multivessel PCI (n = 52,738). Before risk adjustment, compared with PCI, CABG patients were associated with younger age (72.9 vs 75.2 years, P < .001), higher Elixhauser Comorbidity Index (5.0 vs 4.2, P < .001), more diabetes (48.5% vs 42.2%, P < .001), higher cost ($54,154 vs $33,484, P < .001), and longer length of stay (11.9 vs 5.8 days, P < .001). After inverse probability of treatment weighting propensity score adjustment, compared with PCI, CABG was associated with lower hospital mortality (odds ratio, 0.74; P < .001), fewer hospital readmissions at 3 years (odds ratio, 0.85; P < .001), fewer coronary reinterventions (hazard ratio, 0.37; P < .001), and improved 3-year survival (hazard ratio, 0.51; P < .001).

CONCLUSIONS

Contemporary real-world data from Medicare patients with multivessel disease reveal that CABG outcomes were superior to PCI, providing important longitudinal data to guide patient care and policy development.

Socioeconomic Distress Associated With Increased Use of Percutaneous Coronary Intervention Over Coronary Artery Bypass Grafting

BACKGROUND

The influence of socioeconomic determinants of health on choice of percutaneous coronary intervention (PCI) vs coronary artery bypass grafting (CABG) for coronary artery disease is unknown. We hypothesized that higher Distressed Communities Index (DCI) scores, a comprehensive socioeconomic ranking by zip code, would be associated with more frequent PCI.

METHODS

All patients undergoing isolated CABG or PCI in a regional American College of Cardiology CathPCI registry and The Society of Thoracic Surgeons database (2018-2021) were assigned DCI scores (0 = no distress, 100 = severe distress) based on education level, poverty, unemployment, housing vacancies, median income, and business growth. Patients who presented with ST-segment elevation myocardial infarction or emergent procedures were excluded. The most distressed quintile (DCI ≥80) was compared with all other patients. Multivariable logistic regression analyzed the association between DCI and procedure type.

RESULTS

A total of 23 223 patients underwent either PCI (n = 16 079) or CABG (n = 7144) for coronary artery disease across 28 centers during the study period. Before adjustment, high socioeconomic distress occurred more frequently among CABG patients (DCI ≥80, 12.4% vs 8.42%; P < .001). After multivariable adjustment, high socioeconomic distress was associated with greater odds of receiving PCI, relative to CABG (odds ratio 1.26; 95% CI, 1.07-1.49; P = .007). High socioeconomic distress was significantly associated with postprocedural mortality (odds ratio 1.52; 95% CI, 1.02-2.26; P = .039).

CONCLUSIONS

High socioeconomic distress is associated with greater risk-adjusted odds of receiving PCI, relative to CABG, as well as higher postprocedural mortality. Targeted resource allocation in high DCI areas may help eliminate barriers to CABG.

Comparing CABG and PCI across the globe based on current regional registry evidence

There is an ongoing debate whether coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) provide better results for the treatment of coronary artery disease (CAD). We aimed to evaluate the impact of CABG or PCI on long-term survival based on local reports from different regions in the world. We systematically searched MEDLINE selecting studies that compared outcomes for CABG or PCI as a treatment for CAD in the last 10 years. Reports without all-cause mortality, multi-national cohorts, hybrid revascularization populations were excluded. Qualifying studies were statistically compared, and their geographic location visualized on a world map. From 5126 studies, one randomized and twenty-two observational studies (19 risk-adjusted) met the inclusion criteria. The mean follow-up was 4.7 ± 7 years and 18 different countries were included. In 17 studies, CABG was associated with better survival during follow-up, six studies showed no significant difference, and no study favored PCI. Periprocedural mortality was not different in seven, lower with PCI in one, lower with CABG in three and not reported in 12 studies. In regional registry-type comparisons, CABG is associated with better long-term survival compared to PCI in most regions of the world without evidence for higher periprocedural mortality.

It's not all about ISCHEMIA: the case for coronary artery bypass grafting in stable coronary artery disease

PURPOSE OF REVIEW

The recent American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions Guidelines for Coronary Artery Revascularization have raised concerns on the survival benefits of coronary artery bypass grafting (CABG) over guideline-directed medical therapy (GDMT) in stable coronary artery disease (CAD) and appropriate conduit selection for CABG. This review summarizes the evidence supporting CABG for stable CAD and use of the radial artery as a conduit for CABG.

RECENT FINDINGS

CABG has consistently demonstrated a survival benefit over GDMT for patients with stable multivessel CAD. These benefits were more pronounced in patients with diabetes and/or anatomically complex coronary artery disease. The recently published International Study of Comparative Health Effectiveness with Medical and Invasive Approaches trial was not designed to and did not include an appropriate patient population to compare revascularization with CABG to GDMT. These results should thus be viewed in the context of previously published studies. Furthermore, increasing evidence suggests that use of a radial artery in CABG is associated with reduced myocardial infarction and repeat revascularization. This should be considered when selecting the appropriate conduits based on underlying patient factors.

SUMMARY

Readers should be cautious when applying these guidelines broadly. Appropriate consideration of patient and anatomic factors, and in consultation with a multidisciplinary heart team, is important to achieve the best outcomes for patients.

Clinical event rate in patients with and without left main disease undergoing isolated CABG: results from the European DuraGraft registry

OBJECTIVES

Left main coronary artery disease (LMCAD) is considered an independent risk factor for clinical events after coronary artery bypass grafting (CABG). We have conducted a subgroup analysis of the multicentre European DuraGraft registry to investigate clinical event-rates at 1-year in patients with and without LMCAD undergoing isolated CABG in contemporary practice.

METHODS

Patients undergoing isolated CABG were selected. The primary end-point was the incidence of a major adverse cardiac event (MACE) defined as the composite of death, myocardial infarction (MI) or repeat revascularization (RR) at 1-year. The secondary end-point was major adverse cardiac and cerebrovascular events (MACCE) defined as MACE plus stroke. Propensity score matching (PSM) was performed to balance for differences in baseline characteristics.

RESULTS

LMCAD was present in 1,033 (41.2%) and absent in 1,477 (58.8%) patients. At 1-year, the MACE rate was higher for LMCAD patients (8.2% vs 5.1%, p = 0.002) driven by higher rates of death (5.4% vs 3.4%, p = 0.016), MI (3.0% vs 1.3%, p = 0.002) and numerically higher rates of RR (2.8% vs 1.8%, p = 0.13). The incidence of MACCE was 8.8% vs 6.6%, p = 0.043 with a stroke rate of 1.0% and 2.4%, p = 0.011, for LMCAD and non-LMCAD group, respectively. After PSM, the MACE rate was 8.0% vs 5.2%, p = 0.015. The incidence of death was 5.1% vs 3.7%, p = 0.10, MI 3.0% vs 1.4%, p = 0.020, and RR was 2.7% vs 1.6%, p = 0.090, for the LMCAD and non-LMCAD group, respectively. Less strokes occurred in LMCAD patients (1.0% vs 2.4%, p = 0.017). The MACCE rate was not different: 8.5% vs 6.7%, p = 0.12.

CONCLUSIONS

In this large registry, LMCAD was demonstrated to be an independent risk factor for MACE after isolated CABG. Conversely, the risk of stroke was lower in LMCAD patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02922088.

Noteworthy Cardiac Literature From 2021: Coronary Guideline Change Without New Data, Heart Transplant Donation After Cardiac Death, Covid Effects on Global Cardiac Surgery, and Attempt to Improve Dissection Remodeling

Cardiac surgery continues to evolve. The last year has been notable for many reasons. The guidelines for coronary revascularization introduced significant discord. The pandemic continues to affect the care on a global scale. Advances in organ procurement and dissection care move forward with better understanding and better technology.

IACTS position statement on "2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization": section 7.1-a consensus document

American College of Cardiology (ACC), American Heart Association (AHA) and Society for Cardiovascular Angiography and Interventions (SCAI) recently released the Clinical Practice Guidelines for myocardial revascularization [1]. The guidelines were the felt need of the fraternity and this single all-encompassing document, relegating the previous six guidelines on the subject to archives, is indeed welcome. However, the downgrading of coronary artery bypass surgery for stable multivessel coronary artery disease and its bracketing with percutaneous coronary interventions has caused a lot of anguish in the surgical fraternity. This document presents the official viewpoint of the Indian Association of Cardiovascular and Thoracic Surgeons on the matter.