Ten-Year Outcome of Recanalization or Medical Therapy for Concomitant Chronic Total Occlusion After Myocardial Infarction

BACKGROUND

The EXPLORE (Evaluating Xience and Left Ventricular Function in PCI on Occlusions After STEMI) trial was the first and only randomized trial investigating chronic total occlusion (CTO) percutaneous coronary intervention (PCI) early after primary PCI for ST-segment-elevation myocardial infarction, compared with medical therapy for the CTO. We performed a 10-year follow-up of EXPLORE to investigate long-term safety and clinical impact of CTO PCI after ST-segment-elevation myocardial infarction, compared with no-CTO PCI.

METHODS AND RESULTS

In EXPLORE, 302 patients post-ST-segment-elevation myocardial infarction with concurrent CTO were randomized to CTO PCI within ≈1 week or no-CTO PCI. We performed an extended clinical follow-up for the primary end point of major adverse cardiac events, consisting of cardiovascular death, coronary artery bypass grafting, or myocardial infarction. Secondary end points included all-cause death, angina, and dyspnea. Median follow-up was 10 years (interquartile range, 8-11 years). The primary end point occurred in 25% of patients with CTO PCI and in 24% of patients with no-CTO PCI (hazard ratio [HR], 1.11 [95% CI, 0.70-1.76]). Cardiovascular mortality was higher in the CTO PCI group (HR, 2.09 [95% CI, 1.10-2.50]), but all-cause death was similar (HR, 1.53 [95% CI, 0.93-2.50]). Dyspnea relief was more frequent after CTO PCI (83% versus 65%, P=0.005), with no significant difference in angina.

CONCLUSIONS

This 10-year follow-up of patients post-ST-segment-elevation myocardial infarction randomized to CTO PCI or no-CTO PCI demonstrated no clinical benefit of CTO PCI in major adverse cardiac events or overall mortality. However, CTO PCI was associated with a higher cardiovascular mortality compared with no-CTO PCI. Our long-term data support a careful weighing of effective symptom relief against an elevated cardiovascular mortality risk in CTO PCI decisions.

REGISTRATION

URL: https://www.trialregister.nl; Unique identifier: NTR1108.

Safety and efficacy of dedicated guidewire, microcatheter, and guide catheter extension technologies for chronic total coronary occlusion revascularization: Primary results of the Teleflex Chronic Total Occlusion Study

BACKGROUND

Description of procedural outcomes using contemporary techniques that apply specialized coronary guidewires, microcatheters, and guide catheter extensions designed for chronic total occlusion (CTO) percutaneous revascularization is limited.

METHODS

A prospective, multicenter, single-arm study was conducted to evaluate procedural and in-hospital outcomes among 150 patients undergoing attempted CTO revascularization utilizing specialized guidewires, microcatheters and guide extensions. The primary endpoint was defined as successful guidewire recanalization and absence of in-hospital cardiac death, myocardial infarction (MI), or repeat target lesion revascularization (major adverse cardiac events, MACE).

RESULTS

The prevalence of diabetes was 32.7%; prior MI, 48.0%; and previous bypass surgery, 32.7%. Average (mean ± standard deviation) CTO length was 46.9 ± 20.5 mm, and mean J-CTO score was 1.9 ± 0.9. Combined radial and femoral arterial access was performed in 50.0% of cases. Device utilization included: support microcatheter, 100%; guide catheter extension, 64.0%; and mean number of study guidewires/procedure was 4.8 ± 2.6. Overall, procedural success was achieved in 75.3% of patients. The rate of successful guidewire recanalization was 94.7%, and in-hospital MACE was 19.3%. Achievement of TIMI grade 2 or 3 flow was observed in 93.3% of patients. Crossing strategies included antegrade (54.0%), retrograde (1.3%) and combined antegrade/retrograde techniques (44.7%). Clinically significant perforation resulting in hemodynamic instability and/or requiring intervention occurred in 16 (10.7%) patients.

CONCLUSIONS

In a multicenter, prospective registration study, favorable procedural success was achieved despite high lesion complexity using antegrade and retrograde guidewire maneuvers and with acceptable safety, yet with comparably higher risk than conventional non-CTO PCI.

Prognostic Impact of Percutaneous Coronary Intervention of Chronic Total Occlusion in Acute and Periprocedural Myocardial Infarction

Coronary chronic total occlusion (CTO) has gained increasing clinical attention as the most advanced form of coronary artery disease. Prior studies already indicated a clear association of CTO with adverse clinical outcomes, especially in patients with acute myocardial infarction (AMI) and concomitant CTO of the non-infarct-related coronary artery (non-IRA). Nevertheless, the prognostic impact of percutaneous coronary intervention (PCI) of CTO in the acute setting during AMI is still controversial. Due to the complexity of the CTO lesion, CTO-PCI leads to an increased risk of complications compared to non-occlusive coronary lesions. Therefore, this review outlines the prognostic impact of CTO-PCI in patients with AMI. In addition, the prognostic impact of periprocedural myocardial infarction caused by CTO-PCI will be discussed.

A Contemporary Definition of Periprocedural Myocardial Injury After Percutaneous Coronary Intervention of Chronic Total Occlusions

OBJECTIVES

The aim of this study was to assess the prognostic impact of post-procedural troponin T increase and mortality in patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) to define the threshold at which procedure-related myocardial injury drives mortality.

BACKGROUND

Coronary CTO recanalization represents the most technically challenging PCI. The complexity harbors a significant increased risk for complications with CTO PCI with compared with non-CTO PCI. However, there are evidenced biomarker cutoff levels that help identify those patients at risk for unfavorable clinical outcomes.

METHODS

A total of 3,712 consecutive patients undergoing PCI for at least 1 CTO lesion were enrolled, and comprehensive troponin T measurements were performed 6, 8, and 24 h after the procedure. All-cause mortality was defined as the primary study endpoint.

RESULTS

Using spline curve analysis, a more than 18-fold increase of troponin above the upper reference limit was significantly associated with mortality. In a Cox regression analysis, the crude hazard ratio was 2.32 (95% confidence interval: 1.83 to 2.93; p < 0.001) for a ≥18-fold increase compared with patients with post-procedural troponin increase <18-fold of the upper reference limit. Results remained virtually unchanged after bootstrap- or clinical confounder-based adjustment.

CONCLUSIONS

This large-scale outcome study demonstrates for the first time the prognostic value of post-procedural troponin T elevation after PCI in patients with CTOs. A threshold was defined for procedure-related myocardial injury in patients with CTOs to differentiate them from those without CTOs that may help guide post-procedural clinical care in this high-risk patient population.

Retrograde Approach to Chronic Total Occlusion Percutaneous Coronary Intervention

The retrograde approach has increased the success rate of chronic total occlusion percutaneous coronary intervention but has also been associated with a higher risk of complications. The retrograde approach is usually performed in complex lesions, in which the antegrade approach is not feasible or has failed previously. Using a systematic 10-step approach can maximize the likelihood of success and minimize the risks of retrograde chronic total occlusion interventions.

A randomized multicentre trial to compare revascularization with optimal medical therapy for the treatment of chronic total coronary occlusions

Aims

The clinical value of percutaneous coronary intervention (PCI) for chronic coronary total occlusions (CTOs) is not established by randomized trials. This study should compare the benefit of PCI vs. optimal medical therapy (OMT) on the health status in patients with at least one CTO.

Method and results

Three hundred and ninety-six patients were enrolled in a prospective randomized, multicentre, open-label, and controlled clinical trial to compare the treatment by PCI with OMT with a 2:1 randomization ratio. The primary endpoint was the change in health status assessed by the Seattle angina questionnaire (SAQ) between baseline and 12 months follow-up. Fifty-two percent of patients have multi-vessel disease in whom all significant non-occlusive lesions were treated before randomization. An intention-to-treat analysis was performed including 13.4% failed procedures in the PCI group and 7.3% cross-overs in the OMT group. At 12 months, a greater improvement of SAQ subscales was observed with PCI as compared with OMT for angina frequency [5.23, 95% confidence interval (CI) 1.75; 8.71; P = 0.003], and quality of life (6.62, 95% CI 1.78-11.46; P = 0.007), reaching the prespecified significance level of 0.01 for the primary endpoint. Physical limitation (P = 0.02) was also improved in the PCI group. Complete freedom from angina was more frequent with PCI 71.6% than OMT 57.8% (P = 0.008). There was no periprocedural death or myocardial infarction. At 12 months, major adverse cardiac events were comparable between the two groups.

Conclusion

Percutaneous coronary intervention leads to a significant improvement of the health status in patients with stable angina and a CTO as compared with OMT alone.

Trial registration

NCT01760083.

Outcomes with retrograde versus antegrade chronic total occlusion revascularization

OBJECTIVES

The aim of the study was to evaluate the outcomes of retrograde versus antegrade approach in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

The retrograde approach has increased the success rate of CTO PCI but has been associated with a higher risk for complications.

METHODS

We conducted a meta-analysis of studies published between 2000 and August 2019 comparing the in-hospital and long-term outcomes with retrograde versus antegrade CTO PCI.

RESULTS

Twelve observational studies (10,240 patients) met our inclusion criteria (retrograde approach 2,789 patients, antegrade approach 7,451 patients). Lesions treated with the retrograde approach had higher J-CTO score (2.8 vs. 1.9, p < .001). Retrograde CTO PCI was associated with a lower success rate (80.9% vs. 87.4%, p < .001). Both approaches had similar in-hospital mortality, urgent revascularization, and cerebrovascular events. Retrograde CTO PCI was associated with higher risk of in-hospital myocardial infarction (MI; odds ratio [OR] 2.37, 95% confidence intervals [CI] 1.7, 3.32, p < .001), urgent pericardiocentesis (OR 2.53, 95% CI 1.41-4.51, p = .002), and contrast-induced nephropathy (OR 2.12, 95% CI 1.47-3.08; p < .001). During a mean follow-up of 48 ± 31 months retrograde crossing had similar mortality (OR 1.79, 95% CI 0.84-3.81, p = .13), but a higher incidence of MI (OR 2.07, 95% CI 1.1-3.88, p = .02), target vessel revascularization (OR 1.92, 95% CI 1.49-2.46, p < .001), and target lesion revascularization (OR 2.08, 95% CI 1.33-3.28, p = .001).

CONCLUSIONS

Compared with antegrade CTO PCI, retrograde CTO PCI is performed in more complex lesions and is associated with a higher risk for acute and long-term adverse events.

Use of Coronary Computed Tomographic Angiography to Facilitate Percutaneous Coronary Intervention of Chronic Total Occlusions

Chronic total coronary occlusions (CTO) are found frequently in coronary artery disease; however, the technical challenge to open the occlusion by percutaneous coronary intervention is considerably higher than for nonocclusive lesions. The angiographic analysis is limited by the inability to visualize the occluded segment and requires a dual injection approach from donor and recipient vessel to assess the CTO. Therefore, imaging of the CTO by computed tomographic angiography can provide additional information on the vessel course within the CTO segment, specifically the degree and extent of calcification, and maybe even be superior to angiography to analyze the proximal cap morphology. This had been integrated in a score to predict the interventional success. This information provides a valuable means to better plan the procedure and the required strategy. In addition, an integration of the computed tomographic angiography is possible by synchronization with the gantry position and movement of the angiography system during percutaneous coronary intervention, illustrating the course of the occluded segment and possible obstacles in the way. It remains to be established which patient will most likely profit from this additional preprocedural examination involving increased radiation and contrast media exposure and institutional expenses.

Clinical implications of periprocedural myocardial injury in patients undergoing percutaneous coronary intervention for chronic total occlusion: role of antegrade and retrograde crossing techniques

AIMS

Periprocedural myocardial injury (PMI) is frequently observed after percutaneous coronary interventions (PCI) for chronic total occlusion (CTO). We aimed to investigate the prognostic impact of PMI with the antegrade as compared to the retrograde crossing technique.

METHODS AND RESULTS

A total of 1,909 patients undergoing CTO PCI were stratified according to the presence/absence of PMI (elevation of cardiac troponin T [cTnT] >5x99th percentile of normal), and divided according to tertiles of the difference between peak and baseline cTnT within 24 hours (∆cTnT). The primary endpoint was all-cause mortality at a median follow-up of 3.1 (interquartile range 3.0-4.4) years. PMI occurred in 19.4% and 25.4% after antegrade (n=1,447) and retrograde (n=462) procedures (p<0.001). PMI was significantly associated with mortality after antegrade (adjusted HR 1.39, 95% CI: 1.02-1.88, p=0.04), but not retrograde CTO PCI (adjusted HR 0.93, 95% CI: 0.53-1.63, p=0.80, pint=0.02). With the antegrade, but not with the retrograde approach, mortality also increased with tertiles of ∆cTnT (T1: 11.0%, T2: 18.6%, T3: 21.6%, log-rank p<0.001).

CONCLUSIONS

Periprocedural myocardial injury was significantly associated with all-cause mortality following antegrade, but not retrograde CTO PCI. Hence, the higher risk of PMI following retrograde procedures did not translate into worse survival.

Prognostic value of the high-sensitivity troponin T assay after percutaneous intervention of chronic total occlusions

AIMS

The prognostic value of postprocedural high-sensitivity troponin T (hs-TnT) after percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) is currently unclear. We aimed to assess the prognostic value of elevated hs-TnT after elective CTO-PCI.

METHODS

The current study included 409 patients undergoing elective CTO-PCI between September 2011 and August 2016 at two centres who had postprocedural hs-TnT measurements available. Clinical, angiographic and procedural characteristics were correlated with any or at least five times the 99th percentile hs-TnT elevation, as well as a 1-year combined endpoint of major adverse cardiac and cerebrovascular events (MACCE) and mortality.

RESULTS

Post-CTO-PCI hs-TnT elevation was observed in 85% (n = 349/409) and at least five times hs-TnT elevation occurred in 42% (n = 172/409) of cases. hs-TnT elevation was more frequent in more complex patients (postcoronary artery bypass grafting, peripheral vascular disease, chronic kidney disease, heart failure and multivessel disease) as well as in the more complex CTO procedures (higher Japanese CTO complexity, use of retrograde and antegrade dissection re-entry techniques). After 1 year of follow-up (FU), MACCE was not associated with postprocedural hs-TnT elevation, both any elevation (10.9 vs. 11.7%; P = 0.846) and at least five times hs-TnT elevation (15.7 vs. 11.7%; P = 0.451; hazard ratio = 1.375, confidence interval: 0.599-3.157, P = 0.453), compared with no elevation. A nonsignificant trend towards higher mortality in the at least five times hs-TnT vs. no elevation group (4.7 vs. 0%; P = 0.091) was observed.

CONCLUSION

In patients undergoing CTO-PCI, postprocedural hs-TnT elevation is frequent, but is not correlated with higher MACCE and mortality rates after 1-year FU in our small study population, suggestive of the limited long-term impact of troponin elevation.

Safety and efficacy of dedicated guidewire and microcatheter technology for chronic total coronary occlusion revascularization: principal results of the Asahi Intecc Chronic Total Occlusion Study

BACKGROUND

Limited study has detailed the procedural outcomes and utilization of contemporary coronary guidewires and microcatheters designed for chronic total occlusion (CTO) percutaneous revascularization and with application of modern techniques.

PATIENTS AND METHODS

A prospective, multicenter, single-arm trial was conducted to evaluate procedural and in-hospital outcomes among 163 patients undergoing attempted CTO revascularization with specialized guidewires and microcatheters. The primary endpoint was defined as successful guidewire recanalization and absence of in-hospital cardiac death, myocardial infarction, or repeat target vessel revascularization (major adverse cardiac events).

RESULTS

The prevalence of diabetes was 42.9%; prior myocardial infarction, 41.1%; and previous bypass surgery, 36.8%. Average (mean±SD) CTO length was 41±29 mm, and mean Japanese CTO score was 2.6±1.3. A guidewire support catheter was used in 91.7% of cases, and the mean number of CTO-specific guidewires per procedure was 3.1±2.9. Overall, procedural success was observed in 73.0% of patients. The rate of successful guidewire recanalization was 89.0%, and absence of in-hospital major adverse cardiac event was 81.0%. Methods included antegrade (45.4%), retrograde (5.5%) and combined antegrade/retrograde techniques (49.1%). Total mean procedure time was 119±68 min; mean radiation dose, 2613±1881 mGy; and contrast utilization, 287±142 ml. Clinically significant perforation resulting in hemodynamic instability and/or requiring intervention occurred in 13 (8.0%) patients.

CONCLUSION

In this multicenter, prospective registration trial representing contemporary technique, favorable procedural success and early clinical outcomes inform technique and strategy using dedicated CTO guidewires and microcatheters in a high lesion complexity patient population.

Incidence, predictors and longer-term impact of troponin elevation following hybrid chronic total occlusion percutaneous coronary intervention

OBJECTIVES

We examined the incidence of periprocedural cardiac enzyme rise (PCER) [troponin T (TnT) or high-sensivity (hs)TnT >5× the upper limit of normal (ULN)] and periprocedural myocardial infarction (PMI), predictors of PCER and impact of PCER on the longer-term major adverse cardiac events (MACE) following hybrid chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

PCER and PMI after CTO PCI, risk factors for PCER and its impact on longer-term MACE are not fully understood.

METHODS

Among 469 CTO PCI cases performed between 01/2010 and 12/2015, next-day TnT or hsTnT was measured in 455 (97%). We examined the incidence of PCER and PMI (with clinical context or TnT ≥70× ULN). In 269 successful cases who had TnT measured, longer-term MACE (death, MI or target-vessel revascularisation/re-occlusion) were assessed.

RESULTS

Overall, 420 CTOs (92.3%) were treated successfully. PCER was documented in 34%, while PMI in 2.9%. By multivariable analyses, higher J-CTO score (OR = 1.3 per point; P = 0.002), lower creatinine clearance (OR = 1.01 per each cc/min decrease; P < 0.0001) and recent MI (OR = 2.4; P = 0.007) were independent pre-PCI risk factors for PCER. Among procedural variables, retrograde approach (OR = 1.9; P = 0.014) and procedure duration (OR = 1.2 per 30 min; P = 0.007) were associated with PCER. At a median follow-up of 396 days following successful CTO PCI, PCER was not associated with higher MACE (9.3% vs. 8.1%; P = 0.60), and was not a predictor of MACE in multivariable analysis.

CONCLUSIONS

PCER following hybrid CTO PCI is detected in 1/3 of patients. However, true PMI occurs in 2.9%. PCER does not predict adverse long-term outcomes.

Performance of J-CTO and PROGRESS CTO Scores in Predicting Angiographic Success and Long-term Outcomes of Percutaneous Coronary Interventions for Chronic Total Occlusions

Patient selection for and predicting clinical outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) remain challenging. We hypothesized that both J-CTO (Multicenter Chronic Total Occlusion Registry of Japan) and PROGRESS CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) scores will predict not only angiographic success but also long-term clinical outcomes of the patients who underwent PCI of CTO. Of 325 CTO PCIs performed at 2 Emory University hospitals from January 2012 to August 2015, 249 patients with complete baseline clinical, angiographic and follow-up data, were included in this analysis. Major adverse cardiovascular events (MACEs) consisted of a composite of death, myocardial infarction, and target vessel revascularization. Mean age was 63 ± 11 years old and mean follow-up was 19.8 ± 13.1 months. Angiographic success rates increased from 74.5% in 2012 to 85.7% in 2015. Greater J-CTO and PROGRESS CTO scores were not only associated with lower likelihood of angiographic success but also higher rates of long-term MACE. Compared with the scores of 0 to 2, J-CTO and PROGRESS CTO scores of ≥3 were associated with higher MACE. Multivariable analysis demonstrated that PROGRESS CTO scores of ≥3, male sex, and peripheral vascular disease were independent predictors of MACE. In conclusion, J-CTO and PROGRESS CTO scores are useful in predicting procedural success. In addition, the PROGRESS CTO score, and to a lesser degree J-CTO score, have predictive value for long-term outcomes in patients who underwent CTO PCI.

Outcomes With the Use of the Retrograde Approach for Coronary Chronic Total Occlusion Interventions in a Contemporary Multicenter US Registry

BACKGROUND

We sought to examine the efficacy and safety of chronic total occlusion percutaneous coronary intervention using the retrograde approach.

METHODS AND RESULTS

We compared the outcomes of the retrograde versus antegrade-only approach to chronic total occlusion percutaneous coronary intervention among 1301 procedures performed at 11 experienced US centers between 2012 and 2015. The mean age was 65.5±10 years, and 84% of the patients were men with a high prevalence of diabetes mellitus (45%) and previous coronary artery bypass graft surgery (34%). Overall technical and procedural success rates were 90% and 89%, respectively, and in-hospital major adverse cardiovascular events occurred in 31 patients (2.4%). The retrograde approach was used in 539 cases (41%), either as the initial strategy (46%) or after a failed antegrade attempt (54%). When compared with antegrade-only cases, retrograde cases were significantly more complex, both clinically (previous coronary artery bypass graft surgery prevalence, 48% versus 24%; P<0.001) and angiographically (mean Japan-chronic total occlusion score, 3.1±1.0 versus 2.1±1.2; P<0.001) and had lower technical success (85% versus 94%; P<0.001) and higher major adverse cardiovascular events (4.3% versus 1.1%; P<0.001) rates. On multivariable analysis, the presence of suitable collaterals, no smoking, no previous coronary artery bypass graft surgery, and left anterior descending artery target vessel were independently associated with technical success using the retrograde approach.

CONCLUSIONS

The retrograde approach is commonly used in contemporary chronic total occlusion percutaneous coronary intervention, especially among more challenging lesions and patients. Although associated with lower success and higher major adverse cardiovascular event rates in comparison to antegrade-only crossing, retrograde percutaneous coronary intervention remains critical for achieving overall high success rates.

Intravascular Ultrasound Analysis of Intraplaque Versus Subintimal Tracking in Percutaneous Intervention for Coronary Chronic Total Occlusions and Association With Procedural Outcomes

OBJECTIVES

Using intravascular ultrasound (IVUS), the authors compared outcomes by observed wire position (intraplaque vs. subintimal) achieved during successful chronic total occlusion (CTO) lesion treatment.

BACKGROUND

Recent successes in CTO percutaneous coronary intervention (PCI) have used both intraluminal and subintimal wire tracking to improve procedural success. IVUS may be used to determine the course of wire tracking after crossing a CTO.

METHODS

From March 2014 to March 2016, data were collected into a single-center database from 219 patients undergoing CTO PCI with concomitant IVUS imaging. IVUS-visualized wire tracking patterns were then retrospectively examined. Clinical outcomes with a composite in-hospital cardiovascular endpoint of all-cause death, periprocedural myocardial infarction, and in-hospital target lesion revascularization were analyzed along with IVUS-detected vascular injury.

RESULTS

Of the 524 lesions assessed, 219 patients with successfully recanalized CTO lesions had adequate IVUS imaging and were included. Subintimal tracking was detected in 52.1% of overall cases (86.7% dissection re-entry, 27.9% wire escalation). Minimal stent area of the CTO segment and prevalence of significant edge dissection were similar in the 2 groups. In the subintimal tracking group, there was a higher rate of the composite endpoint, mostly driven by periprocedural myocardial infarction. Subintimal tracking was associated with significantly greater IVUS-detected vascular injury, angiographic dye staining/extravasation, and branch occlusion.

CONCLUSIONS

IVUS-detected subintimal tracking is observed in approximately one-half of all successful CTO PCI cases and is associated with an expected higher, yet acceptable, event rate with no difference in minimal stent area or edge dissection among patients undergoing contemporary hybrid CTO PCI.

Approach to CTO Intervention: Overview of Techniques

OPINION STATEMENT

Successful percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs) has been associated with significant clinical benefits, but remains technically demanding. Failure to cross the CTO with a guidewire is the most common cause of CTO PCI failure. CTO crossing can be achieved in the antegrade or retrograde direction and can be accomplished by maintaining true lumen position throughout or via subintimal dissection/reentry techniques. A procedural plan should be created prior to the procedure through careful angiographic review of four key parameters: (a) morphology of the proximal occlusion cap; (b) length of the occlusion; (c) quality of the distal vessel and presence of bifurcation at the distal cap; and (d) suitability of collateral circulation for retrograde crossing. Dual coronary injection is recommended in all cases with contralateral collaterals for detailed characterization of the lesion. If one approach fails to progress, a quick transition to the next approach is encouraged to maximize efficacy and efficiency. Procedural complications, including vessel perforation, may occur more frequently in CTO as compared with non-CTO PCI; hence, availability of necessary equipment and expertise in treating such complications are essential.

Development and Validation of a Scoring System for Predicting Periprocedural Complications During Percutaneous Coronary Interventions of Chronic Total Occlusions: The Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS CTO) Complications Score

BACKGROUND

High success rates are achievable for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) using the hybrid approach, but periprocedural complications remain of concern. Although scores estimating success and efficiency in CTO PCI have been developed, there is currently no available score for estimation of the risk for periprocedural complications. We sought to develop a scoring tool for prediction of periprocedural complications during CTO PCI.

METHODS AND RESULTS

We analyzed data from 1569 CTO PCIs in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS CTO) using a derivation and validation sampling ratio of 2:1. Variables independently associated with periprocedural complications in multivariable analysis in the derivation set were assigned points based on their respective odds ratios. Forty-four (2.8%) patients experienced complications. Three factors were independent predictors of complications and were included in the score: patient age >65 years, +3 points (odds ratio, OR=4.85, CI 1.82-16.77); lesion length ≥23 mm, +2 points (OR=3.22, CI 1.08-13.89); and use of the retrograde approach +1 point (OR=2.41, CI 1.04-6.05). The resulting score showed good calibration and discriminatory capacity in the derivation (Hosmer-Lemeshow χ2 6.271, P=0.281, receiver-operating characteristic [ROC] area=0.758) and validation (Hosmer-Lemeshow χ2 4.551, P=0.473, ROC area=0.793) sets. Score values of 0 to 2, 3 to 4, and ≥5 were defined as low, intermediate, and high risk of complications (derivation cohort 0.4%, 1.8%, 6.5%, P<0.001; validation cohort 0.0%, 2.5%, 6.8%, P<0.001).

CONCLUSIONS

The PROGRESS CTO complication score is a useful tool for prediction of periprocedural complications in CTO PCI.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02061436.

Update on Coronary Chronic Total Occlusion Percutaneous Coronary Intervention

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has significantly evolved during recent years. High success rates are being achieved by experienced centers and operators, but not at less-experienced centers. Use of CTO crossing algorithms can help improve the success and efficiency of these potentially lengthy procedures. There is a paucity of clinical trial data examining clinical outcomes of CTO PCI, which is critical for further adoption and refinement of the procedure. We provide a detailed overview of the clinical evidence and current available crossing strategies, with emphasis on recent developments and techniques.

Impact of Crossing Strategy on Intermediate-term Outcomes After Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

There is ongoing controversy about the optimal crossing strategy selection for chronic total occlusion (CTO) percutaneous coronary intervention (PCI), especially regarding the relative merits of antegrade dissection/re-entry and the retrograde approach.

METHODS

We retrospectively examined the clinical outcomes of 173 consecutive patients who underwent successful CTO PCI at our institution between January 2012 and March 2015.

RESULTS

The mean age was 65 ± 8 years, and 98% of the patients were men with a high prevalence of diabetes (60%), previous coronary artery bypass grafting (CABG) (31%), and previous PCI (54%). The successful CTO crossing strategy was antegrade wire escalation in 79 patients (45.5%), antegrade dissection/re-entry in 58 patients (33.5%), retrograde wire escalation in 11 patients (6.4%), and retrograde dissection and re-entry in 25 patients (14.5%). The retrograde approach was more commonly used in lesions with interventional collaterals (P < 0.0001), moderate/severe calcification (P = 0.02), blunt stump (P = 0.01), and a higher Japan Chronic Total Occlusion score (P = 0.0002). Use of dissection and re-entry (both antegrade and retrograde) was associated with bifurcation and the distal cap (P = 0.004), longer CTO occlusion length (P < 0.0001), and longer stent length (P < 0.0001). Median follow-up was 11 months. The 12-month incidence of death, myocardial infarction, and the composite of acute coronary syndrome/target lesion revascularization/target vessel revascularization was 2.5%, 4.9%, and 24.4%, respectively, and was similar with intimal and subintimal crossing strategies.

CONCLUSIONS

Antegrade dissection/re-entry and retrograde approaches are frequently used during CTO PCI and were associated with similarly favorable intermediate-term outcomes as antegrade wire escalation.

Fatal derecruitment of occluded left anterior descending collaterals after left circumflex revascularization

Coronary arteries are not definitely functionally terminal arteries, as previously thought; indeed, they are linked and interconnected by a rich network of collaterals. Chronic total occlusions (CTOs) represent a subset of frequent lesions encountered in everyday catheterization laboratory practice, generally associated with a developed system of collateral connections. These latter have the capacity to prevent myocardial necrosis and may even uphold metabolic supply to the ischemic territory to maintain its contractile capacity. Authors have reported a rapid and progressive reduction of collateral function and their decline after antegrade flow restoration, resulting in higher myocardial susceptibility to ischemia in the CTO territory. Here, we report the case of a fatal derecruitment of collaterals for a left anterior descending CTO not reopened, after left circumflex subocclusion revascularization.