Should Chronic Total Occlusion Be Treated With Coronary Artery Bypass Grafting? Chronic Total Occlusion Should Not Routinely Be Treated With Coronary Artery Bypass Grafting

Association between hibernating myocardium and collateral circulation in patients with coronary chronic total occlusion

Objective

To explore the association between the quantity of hibernating myocardium (HM) and collateral circulation in patients with coronary chronic total occlusion (CTO).

Materials and methods

88 CTO patients were retrospectively analyzed who underwent evaluation for HM using both 99mTc-sestamibi Single photon emission computed tomography (99mTc-MIBI SPECT) myocardial perfusion imaging (MPI) combined with 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) myocardial metabolism imaging (MMI). They were divided into two groups according Rentrop grading: the poorly/well-developed collateral circulation group (PD/WD group, Rentrop grades 0-1/2-3). After adjusting for the potential confounding factors and conducting a stratified analysis, we explored the association between the HM index within CTO region and the grading of collateral circulation.

Results

In the WD group, the HM index was notably higher than PD group (46.2 ± 15.7% vs. 20.9 ± 16.7%, P < 0.001). When dividing the HM index into tertiles and after adjusting for potential confounders, we observed that the proportion of patients with WD rose as the HM index increased (OR: 1.322, 95% CI: 0.893-1.750, P < 0.001), the proportion of patients with WD was 17.4%, 63.3%, and 88.6% for Tertile 1 to Tertile 3.This increasing trend was statistically significant (OR: 1.369, 95% CI: 0.873-1.864, P < 0.001), especially between Tertile 3 vs. Tertile 1 (OR: 4.330, 95% CI: 1.459-12.850, P = 0.008). Curve fitting displaying an almost linear positive correlation between the two.

Conclusion

The HM index within CTO region is an independent correlation factor for the grading of coronary collateral circulation. A greater HM index corresponded to an increased likelihood of WD.

Chronic Total Occlusions: A State-of-the-Art Review

The percutaneous management of chronic total occlusions (CTO) is a well-established sub-specialty of Interventional Cardiology, requiring specialist equipment, training, and techniques. The heterogeneity of approaches in CTO has led to the generation of multiple algorithms to guide operators in their management. The evidence base for management of CTOs has suffered from inconsistent descriptive and quantitative terminology in defining the nature of lesions and techniques utilised, as well as seemingly contradictory data about improvement in ventricular function, symptoms of angina, and mortality from large-scale registries and randomised controlled trials. Through this review, we explore the history of CTO management and its supporting evidence in detail, with an outline of limitations of CTO-percutaneous coronary intervention and a look at the future of this growing field within cardiology.

Impact of impaired renal function on outcomes of chronic total occlusion undergoing revascularization: a systemic review and meta-analysis

PURPOSE

Patients with chronic kidney disease (CKD) have an associated burden of coronary artery disease, including chronic total occlusions (CTO). It is unclear how the presence of CKD affects the outcomes of CTO revascularization. Previous reviews have not taken into account all relevant published studies that examined the association of CKD with outcomes of CTO revascularization.

METHODS

A systematic search was conducted using PubMed, Scopus, and Google Scholar databases for studies investigating patients with or without CKD who also had coronary chronic total occlusion undergoing revascularization procedures Statistical analysis was performed using STATA software. Effect sizes were reported as pooled relative risk (RR).

RESULTS

A total of 13 studies were included. CKD patients showed elevated risk of in-hospital mortality (RR 4.25, 95% CI 2.64, 6.82) and mortality at latest follow-up (RR 3.24, 95% CI 2.56, 4.11), elevated risk of major cardio or cerebrovascular events (RR 1.65, 95% CI 1.38, 1.98), major bleeding (RR 2.85, 95% CI 1.96, 4.13), and contrast-induced acute kidney injury (RR 3.06, 95% CI 1.70, 5.52). CKD patients also showed lower chances of technical success (RR 0.95, 95% CI 0.91, 1.00).

CONCLUSIONS

The presence of CKD increases the risk of mortality, complications and adversely affects the success of CTO revascularization. Patients with CKD undergoing revascularization should have their kidney function comprehensively evaluated and these patients should be carefully monitored.

In-hospital outcomes of patients with chronic kidney disease undergoing percutaneous coronary intervention for chronic total occlusion: a systematic review and meta-analysis

BACKGROUND

The relative safety and efficacy of percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) in patients with chronic kidney disease (CKD) have not been well defined. We performed a systematic review and meta-analysis of observational studies to assess in-hospital outcomes in this population.

METHODS

We searched MEDLINE, EMBASE, and Cochrane Library databases from inception to April 2020 for all clinical trials and observational studies. Five observational studies with a total of 6769 patients met our inclusion criteria. Patients were divided into two groups based on estimated glomerular filtration rate (eGFR <60 ml/min/1.73m2 in CKD group and ≥ 60 ml/min/1.73m2 in non-CKD group). The primary outcome was in-hospital mortality. Secondary outcomes were acute kidney injury, coronary injury (perforation, dissection or tamponade), stroke and procedural success. Mantel-Haenszel random-effects model was used to calculate the odds ratio (OR) and 95% confidence intervals (CI).

RESULTS

In-hospital mortality was significantly higher among patients with CKD undergoing PCI for CTO (OR: 5.16, 95% CI: 2.60-10.26, P < 0.00001). Acute kidney injury (OR: 2.54, 95% CI: 1.89-3.40, P < 0.00001) and major bleeding (OR: 2.58, 95% CI: 1.20-5.54, P < 0.01) were also more common in the CKD group. No significant difference was observed in the occurrence of stroke (OR: 2.36, 95% CI: 0.74-7.54, P < 0.15) or coronary injury (OR: 1.38, 95% CI: 0.98-1.93, P < 0.06) between the two groups. Non-CKD patients had a higher likelihood of procedural success compared to CKD patients (OR: 0.66, 95% CI: 0.57-0.77, P < 0.00001).

CONCLUSION

Patients with CKD undergoing PCI for CTO have a significantly higher risk of in-hospital mortality, acute kidney injury and major bleeding when compared to non-CKD patients. They also have a lower procedural success rate.

Derivation and validation of the J-CTO extension score for pre-procedural prediction of major adverse cardiac and cerebrovascular events in patients with chronic total occlusions

We developed a prediction model of long-term risk after percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO) based on pre-procedural clinical information. A total of 4,139 eligible patients, who underwent CTO-PCI at 52 Japanese centers were included. Specifically, 1,909 patients with 1-year data were randomly divided into the derivation (n = 1,273) and validation (n = 636) groups. Major adverse cardiac and cardiovascular event (MACCE) was the primary endpoint, including death, stroke, revascularization, and non-fatal myocardial infarction. We assessed the performance of our model using the area under the receiver operating characteristic curve (AUC) and assigned a simplified point-scoring system. One-hundred-thirty-eight (10.8%) patients experienced MACCE in the derivation cohort with hemodialysis (HD: odds ratio [OR] = 2.55), left ventricular ejection fractions (LVEF) <35% (OR = 2.23), in-stent occlusions (ISO: OR = 2.27), and diabetes mellitus (DM: OR = 1.72). The AUC of the derivation model was 0.650. The model's performance was similar in the validation cohort (AUC, 0.610). When assigned a point for each associated factor (HD = 3, LVEF <35%, ISO = 2, and DM = 1 point), the average predicted versus the observed MACCE probability using the Japan-CTO extension score for the low, moderate, high, and very high risk groups was 8.1% vs. 7.3%, 16.9% vs. 15.9%, 22.0% vs. 26.1%, and 56.2% vs. 44.4%, respectively. This novel risk model may allow for the estimation of long-term risk and be useful in disseminating appropriate revascularization procedures.

Transcatheter Aortic Valve Replacement Outcomes Based on the Presence of Chronic Total Occlusion

AIMS

Chronic total occlusion (CTO) has been linked to worse survival. While controversial and limited to observational data, successful CTO percutaneous coronary intervention (PCI) has been associated with improved left ventricular (LV) function and mortality. However, the role of CTO PCI prior to transcatheter aortic valve replacement (TAVR) is not clear. We sought to explore the prognostic impact of a pre-TAVR CTO on post-TAVR outcomes.

METHODS AND RESULTS

We retrospectively reviewed 783 consecutive TAVR cases performed at a single tertiary care medical center. Pre-TAVR angiograms were analyzed for the presence of a CTO. At the time of TAVR, 12.6% (n = 99) patients had a CTO. At one-year post-TAVR, there was no significant association between the presence of a CTO and death (14.2% vs 13.1%, p = 0.75), functional status, quality of life, or adverse events. There was also no difference in long-term survival (4.1 years vs 4.1 years, p = 0.55). LV ejection fraction was lower in the CTO group at baseline and one year (p < 0.01).

CONCLUSIONS

The presence of a CTO did not have any prognostic impact on mortality, change in LV function, or improvement in functional status and angina scores following TAVR in our cohort of elderly, high-risk patients. CTO before TAVR was associated with decreased ejection fraction at baseline and at one year.

Incidence and in-hospital outcomes of single-vessel coronary chronic total occlusion treated with percutaneous coronary intervention

BACKGROUND

Coronary chronic total occlusion (CTO) using percutaneous coronary intervention (PCI) presents a distinct challenge in the field of cardiology owing to multiple reasons including the increased risk of peri-procedural complications. We sought to explore rates of hospitalization, outcomes, use of mechanical circulatory support devices, and economic burden associated with single-vessel coronary CTO undergoing PCI for stable coronary artery disease (CAD).

METHODS

The National Inpatient Sample spanning from 2008 through 2014 was queried to identify hospitalizations associated with single-vessel coronary CTO-PCI for stable CAD by excluding hospitalizations with ST-elevation and non-ST elevation myocardial infarction. Survey-Specific logistic regression was used to analyze adjusted incidence of in-hospital mortality and acute renal failure.

RESULTS

A total of 109,094 hospitalizations were identified as having single-vessel coronary CTO-PCI for stable CAD from 2008 to 2014. An increasing number of coronary CTO-PCI hospitalizations (2465 to 2688 per 100,000 PCI procedures, P_trend < 0.001) with an overall in-hospital mortality of 0.5% was observed. The rate of in-hospital mortality remained unchanged (P_trend = 0.13), but an increasing rate of acute renal failure was observed in the multivariate-adjusted analysis (P_trend < 0.001). Furthermore, a rise in the utilization of intra-aortic balloon pumps and percutaneous left ventricular assist devices during single-vessel coronary CTO-PCI was noted. Taken together, these may account for increasing costs of hospitalization for single-vessel coronary CTO-PCI ($13,909 in 2008 to $17,729 in 2014, P_trend < 0.001).

CONCLUSION

In a large retrospective study, slightly increased rates of single-vessel coronary CTO-PCI for stable CAD were observed. This is accompanied by a rise in morbidity and growing healthcare costs.