Update on Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) lesions can be challenging to perform. In the present review we summarize recent publications in this rapidly evolving area grouped according to indications, outcomes, technique, and complications.

Use of Bivalirudin for Chronic Total Occlusion Percutaneous Intervention: Insights From the PROGRESS-CTO Registry

BACKGROUND

There are limited data on the use of bivalirudin for chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We compared CTO-PCIs performed using bivalirudin vs unfractionated heparin in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO; NCT02061436). The primary endpoint was net adverse cardiac events (NACE), defined as major adverse cardiac events (MACE) and vascular complications.

RESULTS

Between 2012 and 2022, a total of 73 of 9723 procedures (0.75%) were performed using bivalirudin. The J-CTO score (2.4 ± 1.2 vs 2.4 ± 1.3; P=.73) and the PROGRESS-CTO score (1.4 ± 0.9 vs 1.2 ± 1.0; P=.31) were similar in both groups, and the retrograde approach was used less often in the bivalirudin group (15% vs 30%; P<.01). Procedural success (89% vs 85%; P=.35), in-hospital NACE (1.4% vs 2.1%; P>.99), incidence of MACE (0% vs 0.76%; P=.64), and vascular access complications (1.4% vs 0.9%; P=.48) were not different between the 2 groups. On multivariable analysis, use of bivalirudin was not associated with an increased risk of NACE (odds ratio, 0.99; 95% confidence interval, 0.13-7.27).

CONCLUSION

Bivalirudin is infrequently used during retrograde CTO-PCI. While the incidence of adverse events was similar with unfractionated heparin, larger studies are needed to assess the safety of bivalirudin.

Use of Mechanical Circulatory Support in Chronic Total Occlusion Percutaneous Coronary Intervention

The use of mechanical circulatory support (MCS) in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. We analyzed the clinical and angiographic characteristics, and procedural outcomes of 7,171 CTO PCIs performed between 2012 and 2021 at 35 international centers. Mean age was 64.5 ± 10 years, mean left ventricular ejection fraction was 50 ± 13%. MCS was used in 4.5%, prophylactically in 78.7%, and urgently in 21.3%. The most common type of MCS overall was Impella CP (Abiomed) (55.5%), followed by intra-aortic balloon pump (14.8%) and TandemHeart (LivaNova Inc.) (10.0%). Prophylactic MCS patients were more likely to have diabetes mellitus (55% vs 42%, p <0.001) and had more complex lesions compared with cases without prophylactic MCS (Japan-CTO score: 2.80 ± 1.22 vs 2.39 ± 1.27, p <0.001). Cases with prophylactic MCS had similar technical (86% vs 87%, p = 0.643) but lower procedural (80% vs 86%, p = 0.028) success rates and higher rates of periprocedural major cardiac adverse events compared with no prophylactic MCS use (6.55% vs 1.68%, p <0.001). Urgent MCS use was associated with lower technical (68% vs 87%, p <0.001) and procedural (39% vs 86%, p <0.001) success rates and higher major cardiac adverse events compared with no-MCS use (32.26% vs 1.68%, p <0.001). The differences persisted in multivariable analyses. In summary, in this contemporary multicenter registry, MCS was used in 4.5% of CTO PCIs, mostly prophylactically (78.7%). Elective MCS cases had similar technical success but a higher risk of complications. Urgent MCS cases had lower technical and procedural success and higher periprocedural major complication rates.

Educational Experience of Interventional Cardiology Fellows in the United States and Canada

BACKGROUND

The COVID-19 pandemic and iodinated contrast shortage may have affected interventional cardiology (IC) fellowship training.

OBJECTIVES

The aim of this study was to investigate the educational experience of first-year IC fellows in the United States and Canada.

METHODS

A 59-question online survey was conducted among 2021-2022 first-year IC fellows in the United States and Canada.

RESULTS

Of the 360 IC fellows invited to participate, 111 (31%) responded; 95% were from the United States, and 79% were men. Participants were mostly from university programs (70%), spent 61 to 70 hours/week in the hospital, and had an annual percutaneous coronary intervention case number of <200 (5%), 200 to 249 (8%), 250 to 349 (33%), 350 to 499 (39%), 500 to 699 (12%), or ≥700 (3%). For femoral access, a micropuncture needle was used regularly by 89% and ultrasound-guided puncture by 81%, and 43% used vascular closure devices in most cases (>80%). Intravascular ultrasound was performed and interpreted very comfortably by 62% and optical coherence tomography (OCT) by 32%, and 20% did not have access to OCT. Approximately one-third felt very comfortable performing various atherectomy techniques. Covered stents, fat embolization, and coil embolization were used very comfortably by 14%, 4%, and 3%, respectively. Embolic protection devices were used very comfortably by 11% to 24% of IC fellows. Almost one-quarter of fellows (24%) were warned about their high radiation exposure. Eighty-four percent considered IC fellowship somewhat or very stressful, and 16% reported inadequate psychological support.

CONCLUSIONS

This survey highlights opportunities for improvement with regard to the use of intravascular imaging, atherectomy techniques, complication prevention and management strategies, radiation awareness and mitigation, and psychological support.

Single vs. multiple operators for chronic total occlusion percutaneous coronary interventions: From the PROGRESS-CTO Registry

BACKGROUND

There is limited data on the impact of a second attending operator on chronic total occlusion (CTO) percutaneous coronary intervention (PCI) outcomes.

METHODS

We analyzed the association between multiple operators (MOs) (>1 attending operator) and procedural outcomes of 9296 CTO PCIs performed between 2012 and 2021 at 37 centers.

RESULTS

CTO PCI was performed by a single operator (SO) in 85% of the cases and by MOs in 15%. Mean patient age was 64.4 ± 10 years and 81% were men. SO cases were more complex with higher Japan-CTO (2.38 ± 1.29 vs. 2.28 ± 1.20, p = 0.005) and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention scores (1.13 ± 1.01 vs. 0.97 ± 0.93, p < 0.001) compared with MO cases. Procedural time (131 [87, 181] vs. 112 [72, 167] min, p < 0.001), fluoroscopy time (49 [31, 76] vs. 42 [25, 68] min, p < 0.001), air kerma radiation dose (2.32 vs. 2.10, p < 0.001), and contrast volume (230 vs. 210, p < 0.001) were higher in MO cases. Cases performed by MOs and SO had similar technical (86% vs. 86%, p = 0.9) and procedural success rates (84% vs. 85%, p = 0.7), as well as major adverse complication event rates (MACE 2.17% vs. 2.42%, p = 0.6). On multivariable analyses, MOs were not associated with higher technical success or lower MACE rates.

CONCLUSION

In a contemporary, multicenter registry, 15% of CTO PCI cases were performed by multiple operators. Despite being more complex, SO cases had lower procedural and fluoroscopy times, and similar technical and procedural success and risk of complications compared with MO cases.

Validation of the OPEN-CLEAN Chronic Total Occlusion Percutaneous Coronary Intervention Perforation Score in a Multicenter Registry

Coronary artery perforation is one of the most common and feared complications of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We evaluated the utility of the recently presented OPEN-CLEAN (Coronary artery bypass graft, Length of occlusion, Ejection fraction, Age, calcificatioN) perforation score in an independent multicenter CTO PCI dataset. Of the 2,270 patients who underwent CTO PCI at 7 centers, 150 (6.6%) suffered coronary artery perforation. Patients with perforations were older (69 ± 10 vs 65 ± 10, p <0.001), more likely to be women (89% vs 82%, p = 0.010), more likely to have history of previous coronary artery bypass graft (38% vs 20%, p <0.001), and unfavorable angiographic characteristics such as blunt stump (64% vs 42%, p <0.001), proximal cap ambiguity (51% vs 33%, p <0.001), and moderate-severe calcification (57% vs 43%, p = 0.001). Technical success was lower in patients with perforations (69% vs 85%, p <0.001). The area under the receiver operating characteristic curve of the OPEN-CLEAN perforation risk model was 0.74 (95% confidence interval 0.68 to 0.79), with good calibration (Hosmer-Lemeshow p = 0.72). We found that the CTO PCI perforation risk increased with higher OPEN-CLEAN scores: 3.5% (score 0 to 1), 3.1% (score 2), 5.3% (score 3), 7.1% (score 4), 11.5% (score 5), 19.8% (score 6 to 7). In conclusion, given its good performance and ease of preprocedural calculation, the OPEN-CLEAN perforation score appears to be useful for quantifying the perforation risk for patients who underwent CTO PCI.

Development and validation of a scoring system for predicting clinical coronary artery perforation during percutaneous coronary intervention of chronic total occlusions: the PROGRESS-CTO perforation score

BACKGROUND

Coronary artery perforation is a feared complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and often leads to serious adverse clinical events.

AIMS

We sought to develop a risk score to predict clinical coronary artery perforation in patients undergoing CTO PCI.

METHODS

We analysed clinical and angiographic parameters from 9,618 CTO PCIs in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO). Logistic regression prediction modelling was used to identify variables independently associated with clinical perforation, and the model was internally validated with bootstrapping. Clinical coronary artery perforation was defined as any perforation requiring treatment.

RESULTS

The incidence of clinical coronary perforation was 3.8% (n=367). Five factors were independently associated with perforation and were included in the score: patient age ≥65 years +1 point (odds ratio [OR] 1.79, 95% confidence interval [CI]: 1.37-2.33), moderate/severe calcification +1 point (OR 1.85, 95% CI: 1.41-2.42), blunt/no stump +1 point (OR 1.45, 95% CI: 1.10-1.92), use of antegrade dissection and re-entry +1 point (OR 2.43, 95% CI: 1.61-3.69), and use of the retrograde approach +2 points (OR 4.02, 95% CI: 2.95-5.46). The resulting score showed acceptable performance on receiver operating characteristic (ROC) curve (area under the curve [AUC]: 0.741, 95% CI: 0.712-0.773). The Hosmer-Lemeshow test indicated a good fit (p=0.991), and internal validation with bootstrapping demonstrated good agreement with the model with observed AUC: 0.736 (95% bias-corrected CI: 0.706-0.767).

CONCLUSIONS

The PROGRESS-CTO perforation score may be a useful tool for predicting clinical coronary perforation during CTO PCI.

External validation of the PROGRESS-CTO perforation risk score: Individual patient data pooled analysis of three registries

BACKGROUND

Coronary artery perforation is one of the most feared and common complications of chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

To assess the usefulness of the recently developed PROGRESS-CTO (NCT02061436) perforation risk score in independent cohorts. Individual patient-level data pooled analysis of three registries was performed.

RESULTS

Of the 4566 patients who underwent CTO PCI at 25 centers, 196 (4.2%) had coronary artery perforation. Patients with perforations were older (69 ± 10 vs. 65 ± 10, p < 0.001), more likely to be women (19% vs. 13%, p = 0.009), more likely to have a history of prior coronary artery bypass graft (34% vs. 20%, p < 0.001), and unfavorable angiographic characteristics such as blunt stump (62% vs. 48%, p < 0.001), proximal cap ambiguity (52% vs. 34%, p < 0.001), and moderate-severe calcification (60% vs. 49%, p = 0.002). Technical success was lower in patients with perforations (73% vs. 88%, p < 0.001). The area under the receiver operating characteristic curve of the PROGRESS-CTO perforation risk model was 0.76 (95% confidence interval [CI], 0.72-0.79), with good calibration (Hosmer-Lemeshow p = 0.97). We found that the CTO PCI perforation risk increased with higher PROGRESS-CTO perforation scores: 0.3% (score 0), 2.3% (score 1), 3.1% (score 2), 5.5% (score 3), 7.5% (score 4), 14.6% (score 5).

CONCLUSION

Given the good discriminative performance, calibration, and the ease of calculation, the PROGRESS-CTO perforation score may facilitate assessment of the risk of perforation in patients undergoing CTO PCI.

Outcomes of Patients With Acute Coronary Syndromes Undergoing Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

The prevalence and outcomes of patients who presented with an acute coronary syndrome (ACS) and underwent chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have received limited study.

METHODS

We examined the clinical characteristics and procedural outcomes of ACS patients who underwent CTO-PCI in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO; NCT02061436).

RESULTS

Of the 8826 patients who underwent CTO-PCI between 2012 and 2022 at 38 centers, 558 (6.3%) presented with ACS. ACS presentation was with non-ST-segment elevation myocardial infarction (MI) in 54%, unstable angina in 33%, and ST-segment elevation MI in 6.5%. ACS patients were older (66 ± 11 years vs 64 ± 10 years; P<.001) and had higher prevalence of comorbidities such as diabetes mellitus (48% vs 42%; P=.02), prior MI (52% vs 45%; P<.01), and lower left ventricular ejection fraction (49 ± 14% vs 51 ± 13%; P<.01). While the PROGRESS-CTO score (1.4 ± 1.0 vs 1.2 ± 1.0; P<.001) was higher in the ACS group, the J-CTO score was comparable (2.3 ± 1.2 vs 2.4 ± 1.3; P=.68). Technical success (88% vs 86%; P=.12) and the incidence of in-hospital major adverse cardiovascular event (MACE) (0.9% vs 2.1%; P=.06) and adverse events at 3-month follow-up (3.4% vs 7.2%; Kaplan-Meier log-rank P=.16) were similar between ACS and non-ACS patients, respectively.

CONCLUSION

Approximately 6% of patients who underwent CTO-PCI presented with an ACS. Technical success, in-hospital MACE, and the incidence of adverse events up to 3 months were similar between patients who presented with vs without an ACS.

An algorithmic approach to balloon undilatable coronary lesions

Balloon undilatable lesions are lesions that have been successfully crossed by both a guidewire and a balloon but cannot be expanded despite multiple high-pressure balloon inflations. Balloon undilatable lesions can be de novo or in-stent. We describe a systematic, algorithmic approach to treat both de novo and in-stent balloon undilatable lesions using various techniques, such as high-pressure balloon inflation, plaque modification balloons, intravascular lithotripsy, very high-pressure balloon inflation, coronary atherectomy, laser coronary angioplasty, and extraplaque lesion crossing. Knowledge of the various techniques can increase the efficiency, success and safety of the procedure.

Saphenous Vein Graft Occlusion Following Native Vessel Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

Whether saphenous vein grafts (SVGs) should be occluded after successful chronic total occlusion (CTO) percutaneous coronary intervention (PCI) of the corresponding native vessel remains controversial.

METHODS

We analyzed the clinical and angiographic characteristics and procedural outcomes of 51 patients who underwent SVG occlusion following successful CTO-PCI of the corresponding native vessel between 2015 and 2022 at 14 centers.

RESULTS

Mean patient age was 71 ± 8 years and 80% were men. The most common CTO target vessel was the right coronary artery (41%), followed by the left circumflex (37%). Retrograde crossing through the SVG was the successful crossing strategy in 40 cases (78%). SVG occlusion was achieved with coils (1.9 ± 1.0) in 35 of 51 patients (69%) and vascular plugs in the other 16 cases (31%). All procedures were technically successful and the SVG was occluded completely (TIMI 0 flow) in 38 of the cases (75%), with the remaining cases having TIMI 1 flow. Follow-up was available for 37 patients (73%); during a mean follow-up of 312 days from CTO-PCI, the incidence of target-lesion failure due to restenosis was 5.4% (n = 2) with no other major events reported.

CONCLUSION

Following native vessel CTO-PCI, SVG occlusion is often performed and is associated with favorable mid-term outcomes.

Preprocedural coronary computed tomography angiography in chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry

BACKGROUND

Preprocedural coronary computed tomography angiography (CCTA) can be useful in procedural planning for chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined the clinical, angiographic and procedural characteristics and outcomes of cases with vs. without preprocedural CCTA in PROGRESS-CTO (NCT02061436). Multivariable logistic regression was used to adjust for confounding factors.

RESULTS

Of 7034 CTO PCI cases, preprocedural CCTA was used in 375 (5.3%) with increasing frequency over time. Patients with preprocedural CCTA had a higher prevalence of prior coronary artery bypass graft surgery (39% vs. 27%, p < 0.001) and angiographically unfavorable characteristics including higher prevalence of proximal cap ambiguity (52% vs. 33%, p < 0.001) and moderate/severe calcification (59% vs. 41%, p < 0.001) compared with those without CCTA. CCTA helped resolve proximal cap ambiguity in 27%, identified significant calcium not seen on diagnostic angiography in 18%, changed estimated CTO length by >5 mm in 10%, and was performed as part of initial coronary artery disease work up in 19%. CCTA cases had higher J-CTO (2.6 ± 1.2 vs. 2.3 ± 1.3, p < 0.001) and PROGRESS-CTO (1.3 ± 1.0 vs. 1.2 ± 1.0 p = 0.027) scores. After adjusting for potential confounders, cases with preprocedural CCTA had similar technical success (odds ratio [OR]: 1.18, 95% confidence interval [CI], 0.83-1.67) and incidence of major adverse cardiovascular events (OR: 1.47, 95% CI, 0.72-3.00).

CONCLUSION

Preprocedural CCTA was used in ~5% of CTO PCI cases. While CCTA may help with procedural planning, especially in complex cases, technical success and MACE were similar with or without CCTA.

A Systematic Review and Meta-Analysis of Clinical Outcomes of Patients Undergoing Chronic Total Occlusion Percutaneous Coronary Intervention

OBJECTIVES

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) can improve patient symptoms, but it remains controversial whether it impacts subsequent clinical outcomes.

METHODS

In this systematic review and meta-analysis, we queried PubMed, ScienceDirect, Cochrane Library, Web of Science, and Embase databases (last search: September 15, 2021). We investigated the impact of CTO-PCI on clinical events including all-cause mortality, cardiovascular death, myocardial infarction (MI), major adverse cardiovascular event (MACE), stroke, subsequent coronary artery bypass surgery, target-vessel revascularization, and heart failure hospitalizations. Pooled analysis was performed using a random-effects model.

RESULTS

A total of 58 publications with 54,540 patients were included in this analysis, of which 33 were observational studies of successful vs failed CTO-PCI, 19 were observational studies of CTO-PCI vs no CTO-PCI, and 6 were randomized controlled trials (RCTs). In observational studies, but not RCTs, CTO-PCI was associated with better clinical outcomes. Odds ratios (ORs) and 95% confidence intervals (CIs) for all-cause mortality, MACE, and MI were 0.52 (95% CI, 0.42-0.64), 0.46 (95% CI, 0.37-0.58), 0.66 (95% CI, 0.50-0.86), respectively for successful vs failed CTO-PCI studies; 0.38 (95% CI, 0.31-0.45), 0.57 (95% CI, 0.42-0.78), 0.65 (95% CI, 0.42-0.99), respectively, for observational studies of CTO-PCI vs no CTO-PCI; 0.72 (95% CI, 0.39-1.32), 0.69 (95% CI, 0.38-1.25), and 1.04 (95% CI, 0.46-2.37), respectively for RCTs.

CONCLUSIONS

CTO-PCI is associated with better subsequent clinical outcomes in observational studies but not in RCTs. Appropriately powered RCTs are needed to conclusively determine the impact of CTO-PCI on clinical outcomes.

Extraplaque versus intraplaque tracking in chronic total occlusion percutaneous coronary intervention

OBJECTIVE

To compare the clinical outcomes after extraplaque (EP) versus intraplaque (IP) tracking in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

The impact of modern dissection and reentry (DR) techniques on the long-term outcomes of CTO PCI remains controversial.

METHODS

We performed a systematic review and meta-analysis of studies that compared EP versus IP tracking in CTO PCI. Odds ratios (ORs) with 95% confidence intervals (CIs) are calculated using the Der-Simonian and Laird random-effects method.

RESULTS

Our meta-analysis included seven observational studies with 2982 patients. Patients who underwent EP tracking had significantly more complex CTOs with higher J-CTO score, longer lesion length, and more severe calcification and had significantly longer stented segments. During a median follow-up of 12 months (range 9-12 months), EP tracking was associated with a higher risk of major adverse cardiovascular events (MACE) (OR 1.50, 95% CI (1.10-2.06), p = 0.01) and target vessel revascularization (TVR) (OR 1.69, 95% CI (1.15-2.48), p = 0.01) compared with IP tracking. There was no difference in the incidence of all-cause death (OR 1.37, 95% CI (0.67-2.78), p = 0.39), myocardial infarction (MI) (OR 1.48, 95% CI (0.82-2.69), p = 0.20), stent thrombosis (OR 2.09, 95% CI (0.69-6.33), p = 0.19), or cardiac death (OR 1.10, 95% CI (0.39-3.15), p = 0.85) between IP and EP tracking.

CONCLUSION

EP tracking is utilized in more complex CTOs and requires more stents. EP tracking is associated with a higher risk of MACE, driven by a higher risk of TVR at 1 year, but without an increased risk of death or MI compared with IP tracking. EP tracking is critically important for contemporary CTO PCI.

Outcomes and challenges of the provisional stenting technique: Insights from the PROGRESS-BIFURCATION registry

BACKGROUND

Provisional stenting is the most commonly used coronary bifurcation stenting strategy.

METHODS

We examined the clinical and angiographic characteristics, challenges encountered, and procedural outcomes with the provisional bifurcation stenting strategy in the Prospective Global Registry of Percutaneous Coronary Intervention (PCI) in Bifurcation Lesions (PROGRESS-BIFURCATION, NCT05100992).

RESULTS

Provisional stenting was used in 334 of 430 bifurcation interventions (78%). Technical success was lower (95% vs. 100%, p = 0.017) in provisional, but procedural success (90% vs. 95%, p = 0.095) and incidence of in-hospital major adverse cardiovascular events were similar (5% vs. 5%, p = 0.945) compared with two-stent strategies. Provisional was less often preferred in left main/left anterior descending involvement (47% vs. 73%, p < 0.001). Provisional stenting cases had smaller side branch (SB) diameter (2.4 ± 0.5 vs. 2.7 ± 0.6 mm, p < 0.001), shorter SB lesion length (5 [3-8] vs. 10 [5-10] mm, p < 0.001), less SB diameter stenosis (46 ± 35 vs. 81 ± 20%, p < 0.001), and were less likely to be Medina 1,1,1 (34% vs. 73%, p < 0.001). PCI challenges were less common (30% vs. 58%, p < 0.001) with provisional stenting: (1) rewiring difficulty (43%) that was overcome with use of a different wire (74%) or microcatheter (46%); (2) inability to deliver a stent (22%) or balloon (9%) that was overcome with use of a smaller balloon (88%), rewiring (25%), or increased support/microcatheter (25%).

CONCLUSIONS

Provisional bifurcation stenting was more often performed in distal lesions with less SB involvement and had lower technical success, but similar procedural success and complications compared with two-stent strategies.

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.

Association of Annual Operator Volume With the Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention

OBJECTIVES

There are limited data on the association of operator volume with the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We analyzed the association between operator volume and procedural outcomes of 7035 CTO-PCIs performed between 2012 and February 2021 at 30 centers.

RESULTS

The study population was divided into 3 groups based on annual operator CTO-PCI volume: low-volume operators (LVO: &lt;30 cases/year; 39.7% of the cases); medium-volume operators (MVO: 30-60 cases/year; 25.7% of the cases); and high-volume operators (HVO: &gt;60 cases/ year; 34.6% of the cases). Mean patient age was 64.4 ± 10 years and 82% were men. Cases performed by HVOs were more complex, with higher J-CTO score compared with cases performed by MVOs and LVOs (2.72 ± 1.27 vs 2.39 ± 1.19 vs 2.12 ± 1.27, respectively; P&lt;.001). Moderate/severe proximal vessel tortuosity (35% vs 23% vs 20%; P&lt;.001) and proximal cap ambiguity (44% vs 34% vs 32%; P&lt;.001) was also more common in the HVO group. Cases performed by HVOs had higher technical success rates (87.9% vs 86.9% vs 82.6%; P&lt;.001), but also higher rates of periprocedural major cardiac adverse events compared with MVOs and LVOs (3.08% vs 2.71% vs 1.50%; P&lt;.01). On multivariable analyses, HVOs and MVOs were associated with higher technical success.

CONCLUSIONS

In a contemporary, multicenter registry, 40% of CTO-PCI cases are performed by LVOs performing &lt;30 cases per year. Cases performed by HVOs were associated with higher technical and procedural success, but also higher periprocedural major complication rates, potentially due to higher lesion complexity.