Why is disease progression more rapid in the proximal segments of grafted coronary arteries?

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.

Outcomes of chronic total occlusion percutaneous coronary intervention in patients with prior coronary artery bypass graft surgery: Insights from the LATAM CTO registry

OBJECTIVES

To evaluate the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in patients with and without prior coronary artery bypass graft (CABG) surgery.

BACKGROUND

Data on the outcomes of CTO PCI in patients with versus without CABG remains limited and with scarce representation from developing regions like Latin America.

METHODS

We evaluated patients undergoing CTO PCI in 42 centers participating in the LATAM CTO registry between 2008 and 2020. Statistical analyses were stratified according to CABG status. The outcomes of interest were technical and procedural success and in-hospital major adverse cardiac and cerebrovascular events (MACCE).

RESULTS

A total of 1662 patients were included (n = 1411 [84.9%] no-CABG and n = 251 [15.1%] prior-CABG). Compared with no-CABG, those with prior-CABG were older (67 ± 11 vs. 64 ± 11 years; p < 0.001), had more comorbidities and lower left ventricular ejection fraction (52.8 ± 12.8% vs. 54.4 ± 11.7%; p = 0.042). Anatomic complexity was higher in the prior-CABG group (J-CTO score 2.46 ± 1.19 vs. 2.10 ± 1.22; p < 0.001; PROGRESS CTO score 1.28 ± 0.89 vs. 0.91 ± 0.85; p < 0.001). Absence of CABG was associated with lower risk of technical and procedural failure (OR: 0.60, 95% CI: 0.43-0.85 and OR: 0.58, 95% CI: 0.40-0.83, respectively). No significant differences in the incidence of in-hospital MACCE (3.8% no-CABG vs. 4.4% prior-CABG; p = 0.766) were observed between groups.

CONCLUSION

In a contemporary multicenter CTO-PCI registry from Latin America, prior-CABG patients had more comorbidities, higher anatomical complexity, lower success, and similar in-hospital adverse event rates compared with no-CABG patients.

Impact of prior coronary artery bypass grafting in patients undergoing chronic total occlusion-percutaneous coronary intervention: Procedural and clinical outcomes from the REgistry of Crossboss and Hybrid procedures in FrAnce, the NetheRlands, BelGium, and UnitEd Kingdom (RECHARGE)

AIM

Chronic total occlusions (CTO) in patients with history of coronary artery bypass graft (CABG) show more advanced and complex atherosclerotic pathology. Aim of our study is to compare outcomes in patients undergoing CTO percutaneous coronary intervention (PCI) with previous CABG versus those without in the REgistry of Crossboss and Hybrid procedures in FrAnce the NetheRlands, BelGium and UnitEd Kingdom (RECHARGE).

METHODS & RESULTS

The RECHARGE cohort (1,252 patients) was divided in two groups according to the presence of previous CABG (217) or not. We also focused, in the post-CABG group, on a comparison between CTO in previously grafted vessels versus non-grafted vessels. The CTO complexity scores were higher and the success rate (71.9% vs. 88.7%, p < .001) was lower in the CABG group, this difference was driven by higher failure rates in high-complexity-score CTO. The rate of in-hospital complications was similar. In the post-CABG group, the procedural success of CTO located in previously grafted vessels versus those in vessels not previously grafted, was comparably suboptimal (73.1% vs. 68%, p = .47).

CONCLUSION

Patients undergoing CTO PCI with prior CABG have a higher prevalence of comorbidities and more complex lesion characteristics. In the post-CABG population the success rate was significantly lower, particularly in high CTO complexity scores, though complication rates were comparable. In the post-CABG population, the CTO success rate was independent of the presence of a previous graft on the CTO vessel.

Native Coronary Disease Progression Post Coronary Artery Bypass Grafting

BACKGROUND

It remains unclear if graft type impacts native disease progression in the target coronary artery post coronary artery bypass grafting (CABG).

METHODS

Patients who underwent repeat angiograms at least 6 months post CABG with ≥1 arterial graft were included. Pre/post CABG angiograms were examined by 2 experienced readers. Progression was defined as new stenosis of ≥50% in a previously normal coronary, an increase in previous stenosis of ≥20%, or a new occlusion. Primary outcome was the occurrence of native disease progression in bypassed vessels. Secondary outcomes included complete occlusion, left main (LM) and distal disease progression. Cox-proportional hazard regression models were used for time-to-event outcomes.

RESULTS

Study population included 98 patients comprising 263 grafts (143 arterial/120 venous grafts). Median time from surgery to catheterization was 559 days (Interquartile Range 374,910).Ninety-one target vessels showed progression (34.6%) with 75 to complete occlusion (28.5%). Progression was not associated with graft choice (HR 0.74(0.49,1.13) p = 0.163),but was significantly associated with age(p = 0.034),previous PCI(p = 0.002),ACE inhibitor (ACEi) use(p < 0.001),CAD severity (p < 0.001),CCS class III/IV(p = 0.016) and NYHA class III/IV(p < 0.001). Progression to occlusion was significantly associated with SVG (p = 0.019), as well as previous percutaneous coronary intervention (p = 0.007) and ACEi use (p < 0.001). LM disease progression was significantly associated with peripheral vascular disease (HR 5.44(1.92, 15.46), p = 0.001), and not affected by graft type (p = 0.754).

CONCLUSIONS

Native CAD progression in non-LM coronaries is multifactorial, while SVG use was only associated with occlusion of non-LM coronaries. The implications of this study warrant consideration for increased arterial grafting in CABG patients, while the negative associations of previous PCI and ACEi use carry important clinical implications, which require further investigation.

Arterial grafts do not counteract target vessel occlusion

OBJECTIVES

Grafted, non-occluded coronary arteries might contribute substantially to the myocardial blood supply and serve as a basis for vascular collateralization which preserves the myocardium in the event of graft occlusion. Early studies indicated that grafting with saphenous vein, but not internal mammary arteries, accelerates coronary atherosclerosis. This has not been extensively studied for the radial artery, which like the internal mammary artery (IMA) is largely resistant to atherosclerosis. A differential effect of various grafts might facilitate identification of disease-modifying principles. Our surgical cohort represented an opportunity to analyse new native coronary occlusions by comparison with preoperative angiograms.

METHODS

One hundred and two patients underwent angiography 1.3-3.9 years after coronary artery bypass surgery, primarily in order to compare the patency of radial artery, IMA and saphenous vein grafts.

RESULTS

Out of 290 stenotic, grafted vessels, 67 (23%) occluded during follow-up. Native occlusion occurred in 47% of the patients and correlated with serum-cholesterol. In a per target analysis, independent predictors of postoperative native occlusion were the right coronary artery territory, patent corresponding graft, the corresponding graft being an IMA and end-to-side anastomosis.

CONCLUSIONS

Target vessel occlusion is similar with radial artery and saphenous vein grafts and proceeds rapidly even in the current era of secondary prophylaxis against atherosclerosis. Competitive graft flow appears to promote occlusion. Contrary to previous studies, we do not find vein grafts to be inferior to IMA grafts with respect to preservation of native vessel patency.

Percutaneous revascularization strategies in a patient with previous coronary artery bypass surgery: technical and patho-physiological insights

Occasionally, in post-coronary artery bypass patients multiple percutaneous revascularization choices (treatment of the native artery versus treatment of the bypass graft) are available in order to obtain adequate blood supply of the ischemic myocardial region and relief of the anginal symptoms. Once a strategy has been chosen, the possibility to switch to the alternative plan should be considered in case unpredictable complications occur during the first treatment choice. A step-by-step assessment and prediction of the possible acute and long-term outcomes and complications should always be performed in order to optimize the results.