Surgical collateralization: The hidden mechanism for improving prognosis in chronic coronary syndromes

Early and Long-Term Results of Simultaneous and Staged Revascularization of Coronary and Carotid Arteries

BACKGROUND

Carotid artery disease is prevalent among patients with coronary heart disease. The concomitant severe lesions in the carotid and coronary arteries may necessitate either simultaneous or staged revascularization involving coronary bypass and carotid endarterectomy. However, there is presently a lack of consensus on the optimal choice of surgical treatment tactics for patients with significant stenoses in both carotid and coronary arteries. The aim of the current study was to compare the 30-day and long-term outcomes of coronary and carotid artery revascularization surgery based on the simultaneous or staged surgical tactics.

MATERIAL AND METHODS

This single-center retrospective study involved 192 patients with concurrent coronary artery disease and carotid artery stenosis ≥ 70%, of whom 106 patients underwent simultaneous intervention (CABG + CEA) and 86 patients underwent staged CABG/CEA. The mean time between stages ranged from 1 to 4 months (mean 1.88 ± 0.9 months). The endpoints included death from any cause, non-fatal stroke, non-fatal myocardial infarction (MI), and major adverse cardiovascular events (MACEs) (death + non-fatal MI + non-fatal stroke) within 30 days after the last intervention and in the long-term follow-up period (median follow-up-6 years).

RESULTS

The 30-day all-cause mortality, incidence of postoperative non-fatal MI, non-fatal stroke, and MACEs did not exhibit differences between the groups after single-stage and staged interventions. However, the overall risk of postoperative complications (adjusted for the risk of any complication per patient) (OR 2.214, 95% CI 1.048-4.674, p = 0.035), as well as the duration of ventilatory support (p = 0.004), was elevated in the group after simultaneous interventions compared with the staged intervention group. This difference did not result in an increased incidence of death and MACEs in the group after simultaneous interventions. In the long-term follow-up period, there were no significant differences observed when comparing simultaneous or staged surgical tactics in terms of overall survival (54.9% and 62.6% in Groups 1 and 2, respectively, P log-rank = 0.068), non-fatal stroke-free survival (45.6% and 33.6% in Groups 1 and 2, respectively, P log-rank = 0.364), non-fatal MI-survival (57.6% and 73.5% in Groups 1 and 2, respectively, P log-rank = 0.169), and MACE-free survival (7.1% and 30.2% in Groups 1 and 2, respectively, P log-rank = 0.060). The risk factors associated with an unfavorable outcome included age, smoking, BMI, LV EF, and atherosclerosis of the lower extremity arteries.

CONCLUSIONS

This study revealed no significant difference in the impact of simultaneous CABG + CEA or staged CABG/CEA on the incidence of death, stroke, MI, and MACEs over a 30-day and long-term follow-up period. Although the immediate results indicated an increased risk of a complicated course (attributable to overall complications) and more prolonged ventilation after simultaneous CABG + CEA compared with staged CABG/CEA, this did not lead to an increase in fatal complications. Therefore, the implementation of either tactic is considered eligible and appropriate following a thorough operative risk assessment.

Innovation and disruptive science determine the future of cardiothoracic surgery

One of the currently most asked questions in the field of medicine is how any specialty in the future will evolve to ensure better health for the patients by using current, unparalleled developments in all areas of science. This article will give an overview of new and evolving strategies for cardiothoracic (CT) surgery that are available today and will become available in the future in order to achieve this goal. In the founding era of CT surgery in the 1950s and 1960s, there was tremendous excitement about innovation and disruptive science, which eventually resulted in a completely new medical specialty, i.e. CT surgery. Entirely new treatment strategies were introduced for many cardiovascular diseases that had been considered incurable until then. As expected, alternative techniques have evolved in all fields of science during the last few decades, allowing great improvements in diagnostics and treatment in all medical specialties. The future of CT surgery will be determined by an unrestricted and unconditional investment in innovation, disruptive science and our own transformation using current achievements from many other fields. From the multitude of current and future possibilities, I will highlight 4 in this review: improvements in our current techniques, bringing CT surgery to low- and middle-income countries, revolutionizing the perioperative period and treating as yet untreatable diseases. These developments will allow us a continuation of the previously unheard-of treatment possibilities provided by ingenious innovations based on the fundamentals of CT surgery.

[Myocardial revascularization in chronic coronary artery disease. State of art]

The review addresses debatable issues of myocardial revascularization in chronic forms of ischemic heart disease, shows major differences between percutaneous coronary intervention and coronary artery bypass grafting in terms of long-term prognosis, and the dependence of the results on the clinical profile of the disease. The review of current publications demonstrates advantages of open surgery in long-term survival and prevention of adverse outcomes in target groups of patients.

How to deal with nonsevere stenoses in coronary artery bypass grafting - a critical perspective on competitive flow and surgical precision

PURPOSE OF REVIEW

For invasive treatment of coronary artery disease (CAD), we assess anatomical complexity, analyse surgical risk and make heart-team decisions for percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). With PCI, treating flow-relevant lesions is recommended, and reintervention easily treats disease progression. For CABG, some stenoses may only be borderline or nonsevere despite a clear surgical indication. As reoperations are not easy, the question on how to address these lesions has been around from the start, but has never satisfactorily been answered.

RECENT FINDINGS

With a new mechanistic perspective, we had suggested that infarct-prevention by surgical collateralization is the main prognostic mechanism of CABG in chronic coronary syndrome. Importantly, the majority of infarctions arise from nonsevere coronary lesions. Thus, surgical collateralization may be a valid treatment option for nonsevere lesions, but graft patency moves more into focus here, because graft patency directly correlates with the severity of coronary stenoses. In addition, CABG may even accelerate native disease progression.

SUMMARY

We here review the evidence for and against grafting nonsevere CAD lesions, suggesting that patency of grafts (to moderate lesions) may be improved by increasing surgical precision. In addition, we must improve our ability to predict future myocardial infarctions.

The Treatment of Coronary Artery Disease

BACKGROUND

The first coronary artery bypass operation (CABG) was performed on May 2, 1960. The first percutaneous coro - nary intervention (PCI) was performed almost 20 years later. Since then, the invasive treatment of coronary artery disease (CAD) has moved into the spotlight of cardiac medical care.

METHODS

We summarize the current status of medical and invasive CAD treatment through a selective review of the literature.

RESULTS

More than 800 000 patients currently undergo invasive diagnostic and therapeutic procedures for CAD in Germany each year. The number of coronary artery bypass grafting (CABG) procedures rose to 65 000/year by the turn of the millennium and has been declining since then. In contrast, the number of PCIs in Germany rose to approximately 350 000/year by 2017, and a beginning decline is being observed at present. This development occurred even though, for elective patients, a survival advantage from an invasive procedure compared to medical therapy has been shown in direct comparison only for CABG.

CONCLUSION

Conservative treatment is always the baseline treatment and has undergone major advances in the last few decades. Moreover, non-invasive coronary evaluation with computed tomography, as well as non-invasive cardiac stress imaging studies, are increasingly replacing primary invasive coronary evaluations. In this review, we illustrate a mechanistic concept of the appropriate use of CABG and PCI that can improve patient care, while underscoring the importance of interdisciplinary and intersectoral collaboration.

A systematic review and meta-analysis of percutaneous coronary intervention compared to coronary artery bypass grafting in non-ST-elevation acute coronary syndrome

Non-ST-elevation acute coronary syndrome (NSTE-ACS) affects millions of patients. Although an invasive strategy can improve survival, the optimal treatment [i.e., percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG)] is not clear. We performed a meta-analysis of studies reporting outcomes between PCI and CABG in patients with NSTE-ACS. MEDLINE, EMBASE and Cochrane Library were assessed. The primary outcome was long-term mortality. Inverse variance method and random model were performed. We identified 13 observational studies (48,891 patients). No significant difference was found in the primary endpoint [CABG vs. PCI, incidence rate ratio (IRR) 0.93, 95% confidence interval (CI) 0.70; 1.23]. CABG was associated with lower long-term major adverse cardiovascular events (MACE) (IRR 0.64, 95% CI 0.54; 0.76) and lower long-term re-revascularization (IRR 0.37, 95% CI 0.30; 0.47). There was no significant difference in long-term myocardial infarction (CABG vs. PCI, IRR 0.96, 95% CI 0.50; 1.84) and peri-operative mortality (CABG vs. PCI, odds ratio 1.36, 95% CI 0.94; 1.95). For the treatment of NSTE-ACS, CABG and PCI are associated with similar rates of long-term mortality and myocardial infarction. CABG is associated with lower rates of long-term MACE and re-revascularization. Randomized comparisons in this setting are necessary.

Cardiac Surgery 2020 Reviewed

In 2020, nearly 30,000 published references appeared in the PubMed for the search term "cardiac surgery." While SARS-CoV-2 affected the number of surgical procedures, it did not affect outcomes reporting. Using the PRISMA approach, we selected relevant publications and prepared a results-oriented summary. We reviewed primarily the fields of coronary and conventional valve surgery and their overlap with interventional alternatives. The coronary field started with a discussion on trial data value and their interpretation. Registry comparisons of coronary artery bypass surgery (CABG) and percutaneous coronary intervention confirmed outcomes for severe coronary artery disease and advanced comorbidities with CABG. Multiple arterial grafting was best. In aortic valve surgery, meta-analyses of randomized trials report that transcatheter aortic valve implantation may provide a short-term advantage but long-term survival may be better with classic aortic valve replacement (AVR). Minimally invasive AVR and decellularized homografts emerged as hopeful techniques. In mitral and tricuspid valve surgery, excellent perioperative and long-term outcomes were presented for structural mitral regurgitation. For both, coronary and valve surgery, outcomes are strongly dependent on surgeon expertise. Kidney disease increases perioperative risk, but does not limit the surgical treatment effect. Finally, a cursory look is thrown on aortic, transplant, and assist-device surgery with a glimpse into the current stand of xenotransplantation. As in recent years, this article summarizes publications perceived as important by us. It does not expect to be complete and cannot be free of individual interpretation. We aimed to provide up-to-date information for decision-making and patient information.

Role of Concomitant Coronary Artery Bypass Grafting in Valve Surgery for Infective Endocarditis

BACKGROUND

It is current practice to perform concomitant coronary artery bypass grafting (CABG) in patients with infective endocarditis (IE) who have relevant coronary artery disease (CAD). However, CABG may add complexity to the operation. We aimed to investigate the impact of concomitant CABG on perioperative outcomes in patients undergoing surgery for IE.

METHODS

We retrospectively used data of surgically treated IE patients between 1994 and 2018 in six German cardiac surgery centers. We performed inverse probability weighting (IPW), multivariable adjustment, chi-square analysis, and Kaplan-Meier survival estimates.

RESULTS

CAD was reported in 1242/4917 (25%) patients. Among them, 527 received concomitant CABG. After adjustment for basal characteristics between CABG and no-CABG patients using IPW, concomitant CABG was associated with higher postoperative stroke (26% vs. 21%, p = 0.003) and a trend towards higher postoperative hemodialysis (29% vs. 25%, p = 0.052). Thirty-day mortality was similar in both groups (24% vs. 23%, p = 0.370). Multivariate Cox regression analysis after IPW showed that CABG was not associated with better long-term survival (HR: 1.00, 95% CI: 0.82-1.23, p = 0.998).

CONCLUSION

In endocarditis patients with CAD, adding CABG to valve surgery may be associated with a higher likelihood of postoperative stroke without adding long-term survival benefits. Therefore, in the absence of critical CAD, concomitant CABG may be omitted without impacting outcome. The results are limited due to a lack of data on the severity of CAD, and therefore there is a need for a randomized trial.