Risk of New Native-Vessel Occlusion After Coronary Artery Bypass Grafting

Prevalence and outcomes of balloon undilatable chronic total occlusions: Insights from the PROGRESS-CTO

BACKGROUND

The prevalence, treatment, and outcomes of balloon undilatable lesions encountered in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have received limited study.

METHODS

We examined the clinical characteristics and procedural outcomes of balloon undilatable lesions in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO, NCT02061436).

RESULTS

Of 6535 CTO PCIs performed between 2012 and 2022, 558 (8.5%) lesions were balloon undilatable. In this subset, patients were older (mean age 67 ± 10 vs. 64 ± 10, p < 0.001) and had higher prevalence of comorbidities: diabetes mellitus (54% vs. 40%, p < 0.001), prior PCI (71% vs. 59%, p < 0.001), prior myocardial infarction (52% vs. 45%, p = 0.003), and prior coronary artery bypass graft surgery (44% vs. 25%, p < 0.001). The CTO lesion length was estimated to be 34 ± 23 mm, mean J-CTO score was 2.9 ± 1.1 and mean PROGRESS-CTO score was 1.4 ± 1.0. A cutting balloon was used in 27%, a scoring balloon in 15%, laser in 14%, rotational atherectomy in 28%, orbital atherectomy in 10%, intravascular lithotripsy in 1% and other modalities/approaches in 5%. Balloon undilatable lesions had lower technical success (90.9% vs. 93.8%, p = 0.007) and higher incidence of major adverse cardiovascular events (MACE) (composite of in-hospital death, acute myocardial infarction, stroke, re-PCI, emergency CABG, and pericardiocentesis) (5.0% versus 1.3%, p < 0.001).

CONCLUSION

Approximately 1 in 12 CTO (8.5%) lesions are balloon undilatable. Treatment of balloon undilatable lesions is associated with lower technical success and higher in-hospital MACE.

Comparison of hybrid coronary revascularization versus coronary artery bypass grafting in patients with multivessel coronary artery disease: a meta-analysis

BACKGROUND

Percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) are widely used in the treatment of coronary heart disease, but the best revascularization method for multivessel coronary artery disease (MVD) patients is still controversial. Hybrid coronary revascularization (HCR), together with CABG and PCI, have been proved to be feasible methods, but the long-term effect of HCR is not as clear as CABG.

METHOD

By October 2020, we retrieved articles from PubMed, Web of science, EMBASE and Cochrane library databases. The main results are based on major adverse cardiovascular and cerebral events (MACCE).

RESULT

A total of 18 articles (3 randomized controlled trials (RCTs) and 15 observational studies) were included in this meta-analysis. The outcomes of MACCE in the HCR group at perioperative, short-term (30 days to 1 year), medium-term (1 year to 5 years) and long-term (5 years and above) follow-up period were similar to those in the CABG group. The mortality rates of patients in perioperative, short-term and medium-term follow-up were similar to those in the CABG group, but lower than that in the CABG group at long-term follow-up (OR = 0.35, 95% CI 0.18-0.69, p = 0.002). The revascularization rate was higher in the HCR group during the perioperative period (OR = 3.50, 95% CI 2.07-5.94, p < 0.001), short-term (OR = 3.28, 95% CI 1.62-6.64, p < 0.001) and mid-term follow-up (OR = 2.84, 95% CI 1.64-4.92, p < 0.001).

CONCLUSION

Our results reveal that HCR is a safe and therapeutically effective alternative in treatments for MVD patients. It has not only less short-term adverse effect, but also better long-term effect, especially in death.

Chronic Total Occlusion Percutaneous Coronary Intervention in Patients With Prior Coronary Artery Bypass Graft: Current Evidence and Future Perspectives

Coronary chronic total occlusion (CTO), which occurs in 18. 4-52% of all patients referred for coronary angiography, represents one of the last barriers in coronary intervention. Approximately half of all patients with prior coronary artery bypass graft (CABG), who undergo coronary angiography, are diagnosed with coronary CTO. In fact, these patients often develop recurrent symptoms and events, necessitating revascularization. Currently, there is neither a consensus nor developed guidelines for the treatment of CTO patients with prior CABG, and the prognosis of these patients remains unknown. In this review, we discuss current evidence and future perspectives on CTO revascularization in patients with prior CABG, with special emphasis on clinical and lesion characteristics, procedural success rates, periprocedural complications, and long-term outcomes.

Association of Palmar Arch Collateral Function and Radial Artery Occlusion After Transradial Access

The prevalence and implications of radial artery occlusion (RAO) after transradial catheterization are an intensely discussed topic, resulting in numerous preventive strategies such as adjusted anticoagulation, residual-patency hemostasis, or distal puncture site. The present study aimed at assessing an association of palmar arch, in particular radial artery collateral function and RAO after transradial access (TRA) catheterization. Radial artery collateral function was determined using radial artery pressure signals in the nonobstructed vessel and during brief manual occlusion of the more proximal radial artery. Collateral flow index, the ratio of mean occlusive divided by mean nonocclusive arterial blood pressure, both subtracted by central venous pressure, was determined during manual RAO (radial artery collateral flow index [CFI_rad]). The presence or absence of RAO was determined by Doppler ultrasound at least 3 months after TRA. A total of 630 patients with TRA coronary angiography underwent palmar arch, that is, radial and radial plus ulnar artery collateral function assessment. CFI_rad was equal to 0.808 ± 0.144 (95% confidence interval 0.797 to 0.819). A total of 200 patients underwent Doppler ultrasound examination of their forearm arterial circulation 301 ± 140 days after TRA. Eight (4%) patients showed signs of RAO, 4 of whom (2%) had a complete RAO and 4 (2%) a stenosis above 30%. Patients with RAO showed a higher CFI_rad than those without RAO: 0.900 ± 0.074 versus 0.801 ± 0.154 (p = 0.006). In conclusion, complete RAO as determined by Doppler ultrasound later than 3 months after TRA is rare (2%). In the long run, RAO appears to be related to a very well-developed radial artery collateral function.

Resilience of the Internal Mammary Artery to Atherogenesis: Shifting From Risk to Resistance to Address Unmet Needs

Fueled by the global surge in aging, atherosclerotic cardiovascular disease reached pandemic dimensions putting affected individuals at enhanced risk of myocardial infarction, stroke, and premature death. Atherosclerosis is a systemic disease driven by a wide spectrum of factors, including cholesterol, pressure, and disturbed flow. Although all arterial beds encounter a similar atherogenic milieu, the development of atheromatous lesions occurs discontinuously across the vascular system. Indeed, the internal mammary artery possesses unique biological properties that confer protection to intimal growth and atherosclerotic plaque formation, thus making it a conduit of choice for coronary artery bypass grafting. Its endothelium abundantly expresses nitric oxide synthase and shows accentuated nitric oxide release, while its vascular smooth muscle cells exhibit reduced tissue factor expression, high tPA (tissue-type plasminogen activator) production and blunted migration and proliferation, which may collectively mitigate intimal thickening and ultimately the evolution of atheromatous plaques. We aim here to provide insights into the anatomy, physiology, cellular, and molecular aspects of the internal mammary artery thereby elucidating its remarkable resistance to atherogenesis. We propose a change in perspective from risk to resilience to decipher mechanisms of atheroresistance and eventually identification of novel therapeutic targets presently not addressed by currently available remedies.

The association between coronary graft patency and clinical status in patients with coronary artery disease

The concept of a direct association between coronary graft patency and clinical status is generally accepted. However, the relationship is more complex and variable than usually thought. Key issues are the lack of a common definition of graft occlusion and of a standardized imaging protocol for patients undergoing coronary bypass surgery. Factors like the type of graft, the timing of the occlusion, and the amount of myocardium at risk, as well as baseline patients' characteristics, modulate the patency-to-clinical status association. Available evidence suggests that graft occlusion is more often associated with non-fatal events rather than death. Also, graft failure due to competitive flow is generally a benign event, while graft occlusion in a graft-dependent circulation is associated with clinical symptoms. In this systematic review, we summarize the evidence on the association between graft status and clinical outcomes.

Arterial Grafts for Coronary Bypass

Observational and randomized evidence shows that arterial grafts have better patency rates than saphenous vein grafts (SVGs) in coronary artery bypass grafting. Observational studies suggest that the use of multiple arterial grafts is associated with longer postoperative survival, but this must be interpreted in the context of treatment allocation bias and hidden confounders intrinsic to the study designs. Recently, a pooled analysis of 6 randomized trials comparing the radial artery with the SVG as the second conduit and the largest randomized trial comparing the use of single and bilateral internal thoracic arteries have provided apparently divergent results about a clinical benefit with the use of >1 arterial conduit. However, both analyses have methodological limitations that may have influenced their results. At present, it is unclear whether the well-documented increased patency rate of arterial grafts translates into clinical benefits in the majority of patients undergoing coronary artery bypass grafting. A large randomized trial testing the arterial grafts hypothesis (ROMA [Randomized Comparison of the Clinical Outcome of Single Versus Multiple Arterial Grafts]) is underway and will report the results in a few years.

Predictors for New Native-Vessel Occlusion in Patients with Prior Coronary Bypass Surgery: A Single-Center Retrospective Research

Objectives

Chronic total occlusion (CTO) is prevalent in patients with prior coronary artery bypass grafting (CABG). However, data available concerning the prevalence of new-onset CTO of native vessels in patients with prior CABG is limited. Therefore, the objective of the study is to determine predictors for new native-vessel occlusion in patients with prior coronary bypass surgery.

Methods

354 patients with prior CABG receiving follow-up angiography are selected and analyzed in the present study, with clinical and angiographic variables being analyzed by logistic regression to determine the predictors of new native-vessel occlusion.

Results

The overall new occlusion rate was 35.59%, with multiple CTOs (42.06%) being the most prevalent (LAD 24.60% and RCA 18.25%, respectively). Additionally, current smoking (OR: 2.67; 95% CI: 2.60 to 2.74; p=0.01), reduced ejection fraction (OR: 1.76; 95% CI: 1.04 to 2.97; p=0.04), severe stenosis (OR: 3.65; 95% CI: 2.55 to 5.24; p=0.01), and diabetes mellitus (OR: 1.86; 95% CI: 1.34 to 2.97; p=0.04) serve as the independent predictors for new native-vessel occlusion.

Conclusion

As to high incidence of postoperative CTO, appropriate revascularization strategies and postoperative management should be taken into careful consideration.