Successful revascularization improves long-term clinical outcome in patients with chronic coronary total occlusion

Long-term follow-up of patients with chronic total coronary artery occlusion previously randomized to treatment with optimal drug therapy or percutaneous revascularization of chronic total occlusion (COMET-CTO)

Background

The COMET-CTO trial was a randomized prospective study that assessed long-term follow-up in patients with chronic total occlusion (CTO) in coronary arteries treated with percutaneous coronary intervention (PCI) or with optimal medical therapy (OMT). During the 9-month follow-up, the incidence of major adverse cardiac events (MACE) did not differ between the two groups; no death or myocardial infarction (MI) was observed. There was a significant difference in quality of life (QoL), assessed by the Seattle Angina Questionnaire (SAQ), in favor of the PCI group. Here we report long-term follow-up results (56 ± 12 months).

Methods

Between October 2015 and May 2017, a total of 100 patients with CTO were randomized into two groups of 50 patients: PCI CTO or OMT group. The primary endpoint of the current study was the incidence of MACE defined as cardiac death, MI, and revascularization [PCI or coronary artery bypass graft (CABG)]. As the secondary exploratory outcome, we analyzed all the cause-mortality rate.

Results

Out of 100 randomized patients, 92 were available for long-term follow-up (44 in the PCI group and 48 in the OMT group). The incidence of MACE did not differ significantly between the two groups (p = 0.363). Individual components of MACE were distributed, respectively: cardiac death (OMT vs. PCI group, 6 vs. 3, p = 0.489), MI (OMT vs. PCI group, 1 vs. 0, p = 1), and revascularization (PCI: OMT vs. PCI group, 2 vs. 2, p = 1; CABG: OMT vs. PCI group, 1 vs. 1, p = 1). There was no significant difference between the two groups regarding the individual component of MACE. Six patients died from non-cardiac causes [five deaths were reported in the OMT group and one death in the PCI group (p = 0.206)]. Kaplan-Meier survival curves for MACE did not differ significantly between the study groups (log-rank 0.804, p = 0.370). Regarding the secondary exploratory outcome, a total of 15 patients died at 56 ± 12 months (11 in the OMT and 4 in the PCI group) (p = 0.093). The Kaplan-Meier survival curves for all-cause mortality rates did not differ significantly between the two groups (log rank 3.404, p = 0.065). There were no statistically significant differences between OMT and PCI groups in all five SAQ domains. There was a significant improvement in three SAQ domains in the PCI group: PL (p < 0.001), AF (p = 0.007), and QoL (p = 0.001).

Conclusion

After 56 ± 12 months of follow-up, the incidence of MACE, as well as QoL measured by SAQ, did not differ significantly between the PCI and OMT groups.

Procedural Results and Long-Term Outcomes of Percutaneous Coronary Intervention for in-Stent Restenosis Chronic Total Occlusion Compared with de novo Chronic Total Occlusion

Background

In-stent restenosis (ISR) chronic total occlusion (CTO) represents a challenging subgroup for revascularization of CTO by percutaneous coronary intervention (PCI). There are limited data on the treatment and outcomes of PCI for ISR CTO.

Objective

We aimed to evaluate the procedural results and 2-year outcomes of PCI for ISR CTO compared with de novo CTO.

Methods

Patients undergoing attempted CTO PCI between January 2017 and December 2019 were prospectively enrolled. We analyzed the procedural results and 2-year major adverse cardiac events (MACE) in patients undergoing ISR CTO and those undergoing de novo CTO PCI.

Results

A total of 426 patients undergoing 484 consecutive CTO PCI (ISR CTO PCI, n=84; de novo CTO, n=400) were enrolled during the study period. Patients undergoing de novo CTO PCI had a significantly greater syntax score than those undergoing ISR CTO PCI [23.0 (17.5, 30.5) vs 21.5 (14.5, 27.0), p=0.039]. Technical (73.8% vs 79.0%, p=0.296) and procedural (73.8% vs 78.0, p=0.405) success rates, as well as the incidence of major procedural complications (1.2% vs 2.3%, p=0.842), were comparable between the two groups. After a median follow-up of 20 months, patients who underwent ISR CTO PCI had a significantly higher incidence of MACE (33.3% vs 10.3%, p<0.001), mainly attributed to the higher TVR rates (24.7% vs 7.6%, p<0.001). ISR CTO was the only independent predictor of MACE (hazard ratio, 4.124; 95% confidence interval, 1.951–8.717; p<0.001) during follow-up in patients who underwent CTO PCI.

Conclusion

ISR CTO PCI shows comparable technical and procedural success, as well as major procedural complications compared with de novo CTO PCI. However, patients who underwent ISR CTO PCI had a significantly worse prognosis than those who underwent de novo CTO PCI, in terms of MACE, driven by TVR. ISR CTO was the only independent predictor of MACE during the follow-up.

Predictors of unsuccessful endovascular recanalization of coronary chronic total occlusion

The prevalence of endovascular interventions for coronary chronic total occlusion (CTO) remains small worldwide. This is due to the complexity of procedure and the risk of intraoperative complications. In this regard, the search for predictors of unsuccessful endovascular intervention in CTO plays a special role. This will allow for a careful selection of patients with the most favorable expectation effect of the operation. Aim. To identify predictors of unsuccessful endovascular recanalization of CTO.

Material and methods. This retrospective study included 180 patients with chronic coronary artery disease (CAD) in the period from November 2017 to June 2019, who had multivessel lesion in combination with CTO. In all patients, an attempt was made to achieve complete myocardial revascularization. Depending on the success of procedure, the patients were divided into two groups: complete and incomplete myocardial revascularization. The follow-up period was 12 months.

Results. All baseline characteristics of patients in the compared groups were similar. The successful recanalization rate of occlusion was 79,5%. Multivariate regression analysis showed that calcified CTO (p<0,001), baseline SYNTAX (Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) score >32 (p=0,006), CTO length >30 mm (p=0,046) and CTO of circumflex artery (p<0,01) are significant predictors of unsuccessful endovascular recanalization of CTO. To assess the predictive value of the model, a ROC analysis was carried out, and the area under the curve (AUC) was calculated. The AUC was 0,87, which indicates a high predictive quality of the model. The sensitivity and specificity of the model were 78 and 81%, respectively.

Conclusion. The study showed that the presence of calcified CTO, SYNTAX score >32 points, CTO length >30 mm, and CTO of circumflex artery are significant predictors of unsuccessful CTO recanalization.

A contemporary review of clinical significances of percutaneous coronary intervention for chronic total occlusions, with some Japanese insights

The clinical "significance" of percutaneous coronary intervention for coronary chronic total occlusion (CTO-PCI) has been evaluated. In the beginning, the effects on clinical endpoints were investigated by comparisons between cases of success and failure of CTO-PCI, which mostly demonstrated better long-term outcomes in the successful cases. Similarly, improvement of cardiac function or wall motion was proven by serial observational studies. Accordingly, several prospective randomized trials (RCTs), which should confirm such accumulated potential benefits, were recently conducted by comparison with studies of patients that had received optical medical therapy (OMT) alone. While they mostly demonstrated significant improvement of angina symptoms and quality of life (QOL) in the CTO-PCI group, they failed to prove a reduction of clinical events or improvement of left ventricle wall motion, compared with OMT. Concurrent guidelines or consensus documents emphasize that the principal indication for CTO-PCI is to improve symptoms. To determine strategy, the following must be discussed in each individual case: the probability of procedural success, the expectation of long-term patency, and an assessment of the balance between procedure-related complications and overall benefits. In essence, we believe the following facts to be the current sincere appraisal of CTO-PCI: (1) improvements of symptoms and QOL are established, but the others remain inconclusive, and; (2) their margins for improvement are narrowing and numbers of candidates are shrinking. Precision medicine or individualization may be the right directions to take, to enhance the potential of this treatment. This course of action demands discrimination of those candidates who will truly receive benefits from invasive treatment, and that still requires further clinical studies or actions.

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.

The evaluation of technical outcome and wire manipulation time within 30 min in patients with poor distal vessel quality on percutaneous coronary intervention for chronic total occlusion

The technical outcome of poor distal vessel quality (PDV) on chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is yet to be clearly elucidated. PDV has not been evaluated in scoring systems. We examined 193 consecutive CTO-PCIs performed in January 2013-December 2017. The endpoint, including the technical outcomes in these patients between with and without PDV, was analyzed. Moreover, we re-evaluated the predictors for CTO-PCI difficulty according to Japan-CTO score. Out of 193 CTO-PCIs, 181 (93.8%) achieved technical success [including 101 (55.8%) with and 80 (44.2%) without PDV]. In patients with and without PDV, the success rates of guidewire crossing using only the antegrade technique were 46.5% vs. 83.8%, respectively (p < 0.0001) and using the retrograde approach were 53.5% vs. 16.3%, respectively (p < 0.0001). Moreover, there were 56 non-interventional collateral channels in 181 patients. The successful rate of primary antegrade approach was significantly lower and the rate of a rescue retrograde approach was significantly higher with PDV (37.2% vs. 62.8%, 76.9% vs. 23.1%, respectively; p < 0.0119). Significant predictors associated with successful guidewire crossings of ≤ 30 min included blunt stump, calcification, bending, occlusion length ≥ 20 mm, retry lesion following Japan-CTO score, and PDV (p < 0.05, all). Multivariate analyses demonstrated that blunt stump, calcification, bending, retry lesion, and PDV were independent predictors of unsuccessful guidewire crossing of ≤ 30 min (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.13-0.71, p = 0.0039; OR 0.34, 95% CI 0.16-0.71, p = 0.0035; OR 0.17, 95% CI 0.05-0.60, p = 0.0034; OR 0.18, 95% CI 0.06-0.54, p = 0.0008; and OR 0.19, 95% CI 0.09-0.41, p < 0.0001, respectively). PDV could affect the technical outcome of CTO-PCI.