Uncrossable and undilatable lesions-A practical approach to optimizing outcomes in PCI

Review of intravascular lithotripsy for treating coronary, peripheral artery, and valve calcifications

Management of intracoronary calcium (ICC) continues to be a challenge for interventional cardiologists. There have been significant advances in calcium treatment devices. However, there still exists a knowledge gap regarding which devices to choose for the treatment of ICC. The purpose of this manuscript is to review the principles of intravascular lithotripsy (IVL) and clinical data. The technique of IVL will then be compared to alternative calcium treatment devices. Clinical data will be reviewed concerning the treatment of coronary, peripheral artery and valvular calcifications. Controversies to be discussed include how to incorporate IVL into your practice, what is the best approach for treating calcium subtypes, how to approach under-expanded stents, what is the ideal technique for performing IVL, how safe is IVL, whether imaging adds value when performing IVL, and how IVL fits into a treatment program for peripheral arteries and calcified valves.

Safety and feasibility of rotational atherectomy (RA) versus conventional stenting in patients with chronic total occlusion (CTO) lesions: a systematic review and meta-analysis

BACKGROUND AND AIM

Interventional cardiologists face challenges in managing chronic total occlusion (CTO) lesions, with conflicting results when comparing rotational atherectomy (RA) to conventional PCI. This meta-analysis aims to provide a critical evaluation of the safety and feasibility of RA in CTO lesions.

METHODS

PubMed, Scopus, Web of Science, Ovid, and Cochrane central library until April 2023 were searched for relevant studies. MACE was our primary outcomes, other outcomes were all cause of death, cardiac death, MI, and TVR. Also, we reported angiographic outcomes as technical success, procedural success, and procedural complications in a random effect model. The pooled data was analyzed using odds ratio (OR) with its 95% CI using STATA 17 MP.

RESULTS

Seven studies comprising 5494 patients with a mean follow-up of 43.1 months were included in this meta-analysis. Our pooled analysis showed that RA was comparable to PCI to decrease the incidence of MACE (OR = 0.98, 95% CI [0.74 to 1.3], p = 0.9). Moreover, there was no significant difference between RA and conventional PCI in terms of other clinical or angiographic outcomes.

CONCLUSION

Our study showed that RA had comparable clinical and angiographic outcomes as conventional PCI in CTO lesions, which offer interventional cardiologists an expanded perspective when addressing calcified lesions.

PROSPERO REGISTRATION

CRD42023417362.

Techniques to Overcome the Pushability of Robotic-Assisted PCI

Robotic-assisted percutaneous coronary intervention (PCI) was developed with a safety system that limits pushability as compared to manual PCI, thus preventing inadvertent deep delivery of the device and avoiding complications. This safety feature may limit robotic completion when performing intervention to more complex lesions that may require device delivery through calcified or previously stented lesions. In this article, we report three cases that highlight techniques to overcome this limited pushability, resulting in successful robotic completion of the procedures.

Combination of Laser Atherectomy and Super High-pressure Non-compliant Balloon to Treat Stent Under-expansion in Cases of Failed Interventional Options

Patients with calcified, fibrotic native coronary vessels with prior suboptimal stenting outcomes are at major risk of stent thrombosis and could face serious consequences if untreated. In cases of multiple layers of under-expanded stents, the risk is multiplied. If conventional balloon post-dilatation is unsuccessful after stent implantation without proper lesion preparation, few interventional options remain. The authors report on a patient with prior numerous right coronary unsuccessful coronary interventions resulting in partially crushed multiple layers of stent material with critical lumen narrowing caused by stent under-expansion. Balloon angioplasty and stent rotational atherectomy (ROTA) had been attempted to overcome stent under-expansion but were unsuccessful. The authors investigated a new combination therapy of laser atherectomy (ELCA) and super high-pressure balloon (OPN non-compliant balloon) to treat single or multiple layers of stent with severe under-expansion due to fibrotic, calcified tissue surrounding the under-expanded stent structure.

Contemporary issues of percutaneous coronary intervention in heavily calcified chronic total occlusions: an expert review from the European CTO Club

Severe calcification is frequent in coronary chronic total occlusions (CTO), and its presence has been associated with increased procedural complexity and poor long-term outcomes following percutaneous coronary intervention (PCI) in an already challenging anatomical setting. The diagnostic characterisation of heavily calcified CTOs using non-invasive and invasive imaging tools can lead to the application of different therapeutic options during CTO PCI, in order to achieve adequate lesion preparation and optimal stent implantation. In this expert review, the European Chronic Total Occlusion Club provides a contemporary, methodological approach, specifically addressing heavily calcified CTOs, suggesting an integration of evidence-based diagnostic methods to tailored, up-to-date percutaneous therapeutic options.

Angiographic Features and Clinical Outcomes of Balloon Uncrossable Lesions during Chronic Total Occlusion Percutaneous Coronary Intervention

Background: Balloon uncrossable lesions are defined as lesions that cannot be crossed with a balloon after successful guidewire crossing. Methods: We analyzed the association between balloon uncrossable lesions and procedural outcomes of 8671 chronic total occlusions (CTOs) percutaneous coronary interventions (PCIs) performed between 2012 and 2022 at 41 centers. Results: The prevalence of balloon uncrossable lesions was 9.2%. The mean patient age was 64.2 ± 10 years and 80% were men. Patients with balloon uncrossable lesions were older (67.3 ± 9 vs. 63.9 ± 10, p < 0.001) and more likely to have prior coronary artery bypass graft surgery (40% vs. 25%, p < 0.001) and diabetes mellitus (50% vs. 42%, p < 0.001) compared with patients who had balloon crossable lesions. In-stent restenosis (23% vs. 16%. p < 0.001), moderate/severe calcification (68% vs. 40%, p < 0.001), and moderate/severe proximal vessel tortuosity (36% vs. 25%, p < 0.001) were more common in balloon uncrossable lesions. Procedure time (132 (90, 197) vs. 109 (71, 160) min, p < 0.001) was longer and the air kerma radiation dose (2.55 (1.41, 4.23) vs. 1.97 (1.10, 3.40) min, p < 0.001) was higher in balloon uncrossable lesions, while these lesions displayed lower technical (91% vs. 99%, p < 0.001) and procedural (88% vs. 96%, p < 0.001) success rates and higher major adverse cardiac event (MACE) rates (3.14% vs. 1.49%, p < 0.001). Several techniques were required for balloon uncrossable lesions. Conclusion: In a contemporary, multicenter registry, 9.2% of the successfully crossed CTOs were initially balloon uncrossable. Balloon uncrossable lesions exhibited lower technical and procedural success rates and a higher risk of complications compared with balloon crossable lesions.

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.

Rotational atherectomy for chronically and totally occluded coronary lesions: A propensity score-matched outcomes study

Background

Despite advances being made in techniques and devices, certain chronic total occlusion (CTO) lesions remain uncrossable or undilatable. Rotational atherectomy (RA) is usually necessary for such lesions to achieve successful revascularization.

Methods

Information regarding consecutive patients who underwent coronary RA was retrieved from the catheterization laboratory database. Patients who underwent RA for CTO lesion refractory using other conventional devices were recruited, with propensity score-matched cases serving as controls.

Results

A total of 411 patients underwent coronary RA in the study period. Most patients had high-risk features (65.7% had acute coronary syndrome (ACS), 14.1% ischemic cardiomyopathy, and 5.1% cardiogenic shock), while only 20.2% of the patients had stable angina. Among them, 44 patients underwent RA for CTO lesions (CTO group), whereas the propensity score matched controls consist of 37 patients (non-CTO group). The baseline characteristics, high-risk features, coronary artery disease (CAD) vessel numbers, left ventricular function and biochemistry profiles of both groups were the same except for more patients with diabetes (67.6% vs. 45.5%, p = 0.046) in the non-CTO group and more 1.25 mm burr uses in the CTO group. There were no significant differences in acute procedural outcomes or incidence of acute contrast-induced nephropathy (CIN), and no patient demanded emergent CABG or died during the procedure. There was no significant difference in major adverse cardiovascular events (MACE), CV MACE or individual components between the two groups in the hospital, at 30, 90, and 180 days or at 1 year.

Conclusion

In comparison with the propensity risk factor scores-matched controls, there was no difference in procedural complications, acute CIN or clinical outcomes during various stages of RA for CTO lesions. RA for CTO patients was highly efficient and showed safety and outcome profiles similar to those for non-CTO lesions.

A State-of-the-Art Review: The Percutaneous Treatment of Highly Calcified Lesions

Coronary artery calcification is prevalent in coronary heart disease with its progression being predictive of future adverse cardiac events. Its presence is considered to be a marker of interventional procedural complexity. Several adjunctive percutaneous coronary intervention tools, such as modifying balloons, atherectomy devices and intravascular lithotripsy, now exist to successfully treat calcified lesions. In this state-of-the-art review, a step-wise progression of strategies is described to modify coronary plaque, from well-recognised techniques to techniques that should only be considered when standard manoeuvres have proven unsuccessful. Technology has advanced greatly over the past few decades and we discuss how future technologies might shape percutaneous intervention.

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.

Intravascular lithotripsy in chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry

BACKGROUND

The use of intravascular lithotripsy (IVL) in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study.

METHODS

We analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 82 CTO PCIs that required IVL at 14 centers between 2020 and 2022.

RESULTS

During the study period, IVL was used in 82 of 3301 (2.5%) CTO PCI procedures (0.4% in 2020 and 7% in 2022; p for trend < 0.001). Mean patient age was 69 ± 11 years and 79% were men. The prevalence of hypertension (95%), diabetes mellitus (62%), and prior PCI (61%) was high. The most common target vessel was the right coronary artery (54%), followed by the left circumflex (23%). The mean J-CTO and PROGRESS-CTO scores were 2.8 ± 1.1 and 1.3 ± 1.0, respectively. Antegrade wiring was the final successful crossing strategy in 65% and the retrograde approach was used in 22%. IVL was used in 10% of all heavily calcified lesions and 11% of all balloon undilatable lesions. The 3.5 mm lithotripsy balloon was the most commonly used balloon (28%). The mean number of pulses per lithotripsy run was 33 ± 32 and the median duration of lithotripsy was 80  (interquartile range: 40-103) seconds. Technical and procedural success was achieved in 77 (94%) and 74 (90%) cases, respectively. Two (2.4%) Ellis Class 2 perforations occurred after IVL use and were managed conservatively.

CONCLUSION

IVL is increasingly being used in CTO PCI with encouraging outcomes.

Reasons for lesion uncrossability as assessed by intravascular ultrasound

OBJECTIVES

The purpose of the current study was to use intravascular ultrasound (IVUS) to clarify anatomical and morphological lesion characteristics of uncrossable lesions.

BACKGROUND

Uncrossable lesions are not always severely calcified. The prevalence of uncrossable lesions that are nonseverely calcified as well as other mechanisms for uncrossability has not been well clarified.

METHODS

A total of 252 de novo uncrossable lesions in native coronary arteries that underwent either rotational or orbital atherectomy due to inability of any balloon to cross the lesion and 38 lesions with severe calcium in which IVUS crossed preatherectomy were included. Severe calcium is defined as maximum arc of calcium ≥270°.

RESULTS

Severe calcification was absent in 16% of uncrossable lesions, 83% of which had a significant vessel bend. Compared with crossable lesions with severe calcium, uncrossable lesions with severe calcium more often had a bend in the vessel (71% vs. 21%, p < 0.001) and a longer length of continuous severe calcium (median length of calcium ≥270° 3.8 mm vs. 1.9 mm, p = 0.001). Other than severe calcium (especially long continuous calcium) or a bend in the vessel, anatomical factors associated with uncrossabilty were aorto-ostial lesion location and small vessels.

CONCLUSIONS

Uncrossable lesions are not always severely calcified. The interaction of lesion morphology (continuous long and large arcs of calcium) and vessel geometry (bend in the vessel or ostial lesion location) affect lesion crossability.

Combined use of rotational and excimer lASER coronary atherectomy (RASER) during complex coronary angioplasty-An analysis of cases (2006-2016) from the British Cardiovascular Intervention Society database

INTRODUCTION

Combining rotational (RA) and excimer laser coronary atherectomy (ELCA)-RASER atherectomy-is technique utilized in the percutaneous management of calcific coronary disease. The evidence base examining its safety and utility is sparse and limited to small case-series. This study examines the patterns and outcomes of RASER atherectomy use in the largest cohort to date.

METHODS

Using the British Cardiac Intervention Society database, data were analyzed on all PCI procedures in the UK between 2006 and 2016. Descriptive statistics and multivariate logistic regressions were used to examine baseline, procedural, and outcome associations with RASER.

RESULTS

We identified 153 (0.02%) RASER atherectomy cases out of 686,358 PCI procedures. Baseline covariates associated with RASER use were age, BMI, diabetes, stable coronary disease, and previous CABG. Procedural co-variates associated with RASER were CTO-PCI, the use of more/longer stents, intravascular imaging, cutting balloons, and microcatheters. Adjusted rates of in-hospital major adverse cardiac/cerebrovascular events (MACCE) were not significantly different with RASER. However, there were higher odds of arterial complications (OR 3.23, 95% CI: 1.58-6.61), slow flow (OR 3.50, 95% CI: 1.29-9.55), and shock induction (OR 9.66, 95% CI: 3.44-27.06).

CONCLUSIONS

RASER atherectomy use in complex PCI is associated with higher risk baseline and procedural characteristics. Although increased rates of shock induction, slow flow, and arterial complications were observed, RASER does not increase the likelihood of in-hospital MACCE, major bleeding, or death.

Laser for balloon uncrossable and undilatable chronic total occlusion interventions

BACKGROUND

There is limited information on use of laser in complex percutaneous coronary interventions (PCI). We examined the impact of laser on the outcomes of balloon uncrossable and balloon undilatable chronic total occlusion (CTO) PCI.

METHODS

We reviewed baseline clinical and angiographic characteristics and procedural outcomes of 4845 CTO PCIs performed between 2012 and 2020 at 32 centers.

RESULTS

Of the 4845 CTO lesions, 752 (15.5%) were balloon uncrossable (523 cases) or balloon undilatable (356 cases) and were included in this analysis. Mean patient age was 66.9 ± 10 years and 83% were men. Laser was used in 20.3% of the lesions. Compared with cases in which laser was not used, laser was more commonly used in longer length occlusions (33 [21, 50] vs. 25 [15, 40] mm, p = 0.0004) and in-stent restenotic lesions (41% vs. 20%, p < 0.0001). Laser use was associated with higher technical (91.5% vs. 83.1%, p = 0.010) and procedural (88.9% vs. 81.6%, p = 0.033) success rates and similar incidence of major adverse cardiac events (3.92% vs. 3.51%, p = 0.805). Laser use was associated with longer procedural (169 [109, 231] vs. 130 [87, 199], p < 0.0001) and fluoroscopy time (64 [40, 94] vs. 50 [31, 81], p = 0.003).

CONCLUSIONS

In a contemporary, multicenter registry balloon uncrossable and balloon undilatable lesions represented 15.5% of all CTO PCIs. Laser was used in approximately one-fifth of these cases and was associated with high technical and procedural success and similar major complication rates.

An ultra-low-profile 0.85 mm Nano Hydro balloon to treat wire-crossable balloon-uncrossable lesions: A useful tool in CTO armamentarium

Balloon uncrossable lesions are commonly encountered during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). A sequential strategy and planning are required to tackle such lesions. We present a case series of severely calcified, device uncrossable lesions where the traditional strategies failed and an ultra-low-profile (0.85 mm) balloon was crucial to successful PCI. To our best knowledge, this is the first case series describing the use of this balloon in real world.

Rota-Lithotripsy-A Novel Bail-Out Strategy for Calcified Coronary Lesions in Acute Coronary Syndrome. The First-in-Man Experience

Heavy calcification remains one of the greatest challenges in the treatment of coronary artery disease (CAD), especially in subjects with an acute coronary syndrome (ACS). In the present case series study of high-risk patients with ACS, including both STEMI and NSTEMI, we performed a rota-lithotripsy-a combination of rotational atherectomy with subsequent intravascular lithotripsy-as a novel bail-out strategy to facilitate stent delivery in a tortuous calcified coronary artery.