Current status of rotational atherectomy

Effectiveness and Safety of a Novel Intravascular Lithotripsy System for Severe Coronary Calcification: The CALCI-CRACK Trial

BACKGROUND

Intravascular lithotripsy is effective and safe for managing coronary calcification; however, available devices are limited, and complex lesions have been excluded in previous studies. This study aimed to investigate the effectiveness and safety of a novel intravascular lithotripsy system for severe calcification in a population with complex lesions.

METHODS

CALCI-CRACK (treatment of severe calcified coronary lesions with a novel intracoronary shock wave lithotripsy system) (ChiCTR2100052058) was a prospective, single-arm, multicentre study. The primary end point was the procedural success rate. Major safety end points included major adverse cardiovascular events (MACE) and target lesion failure (TLF) at 30 days and 6 months, and severe angiographic complications. Calcification morphology was assessed in the optical coherence tomography (OCT) subgroup.

RESULTS

In total, 242 patients from 15 high-volume Chinese centres were enrolled, including 26.45% of patients with true bifurcation lesions, 3.31% with severely tortuous vessels, and 2.48% with chronic total occlusion, respectively. The procedural success rate was 95.04% (95% confidence interval 91.50%-97.41%), exceeding the prespecified performance goal of 83.4% (P < 0.001). The 30-day and 6-month MACE rates were 4.13% and 4.55%, respectively. TLF rates at those time points were 1.24% and 1.65%, respectively. Severe angiographic complications occurred in 0.42% of patients. In the OCT subgroup (n = 93), 93.55% of calcified lesions were fractured, and minimal lumen area increased from 1.55 ± 0.55 mm2 to 4.91 ± 1.22 mm2 after stent implantation, with acute gain rate of 245 ± 102%.

CONCLUSIONS

The novel intravascular lithotripsy system is effective and safe for managing severely calcified coronary lesions in a cohort that included true bifurcation lesions, severely tortuous vessels, and chronic total occlusion.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR), number ChiCTR2100052058.

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.

Iatrogenic coronary dissection: state of the art management

Iatrogenic coronary artery dissections (ICAD) are rare but potentially devastating complications during coronary angiography and percutaneous coronary interventions (PCI). Intima media complex separation may be produced either by the catheter tip or during PCI. Patient characteristics and procedure related risk factors are intimately linked to catheter induced ICAD over diagnostic angiography. Moreover, the increasing complexity of patients undergoing PCI, which frequently involves treatment of heavily calcified or occluded vessels, has increased the likelihood of dissections during PCI. A prompt recognition, along with a prompt management (either percutaneous, surgical or even careful watching), are key in preventing catastrophic consequences of ICAD, such as left ventricular dysfunction, cardiogenic shock, periprocedural myocardial infarction (MI) or cardiac death. This review aims to summarize the main updates concerning the pathophysiology, highlight key risk factors and suggest recommendations in management and treatment of ICAD.

Coronary Lithotripsy as Elective or Bail-Out Strategy After Rotational Atherectomy in the Rota-Shock Registry

Debulking lesions with severe coronary artery calcification (CAC) is highly recommended to obtain good procedural and long-term success. Utilization and performance of coronary intravascular lithotripsy (IVL) after rotational atherectomy (RA) has not been thoroughly studied. This study aimed to evaluate the efficacy and safety of IVL with the Shockwave Coronary Rx Lithotripsy System in lesions with severe CAC as elective or bail-out strategy after RA. This observational, prospective, single-arm, multicenter, international, open-label Rota-Shock registry included patients with symptomatic coronary artery disease and lesions with severe CAC treated by percutaneous coronary intervention, including lesion preparation with RA and IVL, at 23 high-volume centers. Primary efficacy end point was procedural success, defined as final diameter stenosis <30% by quantitative coronary angiography. Primary safety end point was freedom from serious angiographic complications, which included >National Heart, Lung and Blood Institute type B dissection, perforation, abrupt closure, slow or no flow, final thrombolysis in myocardial infarction flow <3, and acute thrombosis. A total of 160 patients were enrolled between June 2020 and June 2022. The primary efficacy end point was observed in 155 patients (96.9%). The primary safety end point occurred in 145 cases (90.6%). Dissections >National Heart, Lung and Blood Institute type B occurred in 3 patients (1.9%), whereas slow or no flow occurred in 8 (5.0%), final thrombolysis in myocardial infarction flow <3 in 3 (1.9%), and perforation in 4 patients (2.5%). Free from inhospital major adverse cardiac and cerebrovascular events, including cardiac death, target vessel myocardial infarction, target lesion revascularization, cerebrovascular accident, definite/probable stent thrombosis, and major bleeding, occurred in 158 patients (98.7%). In conclusion, IVL after RA in lesions with severe CAC was effective and safe, with a very low incidence of complications as either elective or bail-out strategy.

Comparison of Two Different Rota-Flush Solutions in Patients Undergoing Rotational Atherectomy: A Randomized, Controlled, Triple-Blind Trial

INTRODUCTION

This prospective study accessed the feasibility and safety of the heparin rota-flush solution in patients undergoing rotational atherectomy (RA).

METHODS

Between August 2019 and November 2021, 200 patients who underwent RA were included in this study, among whom 103 (51.5%) were randomly allocated into the heparin rota-flush group and 97 (48.5%) into the traditional rota-flush group. The primary endpoint was the incidence of slow flow/no-reflow after RA; the secondary endpoints were procedural success, RA-related procedural complications, and in-hospital major adverse cardiovascular events (MACE).

RESULTS

There were no significant differences in baseline clinical and angiographic characteristics between the two groups. Thirty patients (29.1%) in the heparin rota-flush group and nineteen patients (19.6%) in the traditional rota-flush groups developed slow flow/no-reflow (P = 0.117), respectively, and procedural success was also comparable (97.1% vs. 93.8%, P = 0.320). Severe hypotension (systolic blood pressure < 90 mmHg) was not significantly different (15.5% vs. 16.5%, P = 0.841), but the incidence of coronary spasm was significantly higher in the heparin rota-flush group (42.7% vs. 22.7%, P = 0.003). MACE including stent-thrombosis (ST), target-lesion revascularization (TLR), and cardiac death were also comparable between the two groups; no stroke was observed.

CONCLUSIONS

The findings suggest that although continuous intracoronary infusion of heparin rota-flush solution does not increase the incidence of slow flow/no-reflow, traditional rota-flush solution without RotaGlide prevents coronary spasm more effectively compared to the heparin rota-flush without significant impact on severe hypotension. These results do not support a strategy of routine use of heparin rota-flush solution in patients receiving RA procedures.

Angiographic predictors of unplanned rotational atherectomy in complex calcified coronary artery disease: a pooled analysis from the randomised ROTAXUS and PREPARE-CALC trials

BACKGROUND

Calcified coronary lesions present therapeutic challenges for the interventional cardiologist, often requiring rotational atherectomy (RA).

AIMS

This study aimed to develop an angiographic scoring tool to predict the need for a priori RA.

METHODS

A pooled analysis of the randomised ROTAXUS and PREPARE-CALC studies was carried out, (N=220 patients, N=313 lesions), by virtue of the fact that both studies made provision for crossover to RA (from balloon dilatation or modified balloon dilatation, respectively). Logistical regression techniques were employed to assess for the presence of patient- or lesion-specific factors leading to a necessity for RA. External validation was performed though retrospective calculation of the score for 192 patients who underwent bail-out RA in a single centre.

RESULTS

Lesion length (odds ratio [OR] 1.02, 95% confidence interval [CI]: 1.00-1.04 per mm, p=0.04), bifurcation lesion (OR 2.60, 95% CI: 1.27-5.30, p=0.009), vessel tortuosity >45° (OR 3.49, 95% CI: 1.73-7.03, p<0.001) and severe vessel calcification (OR 11.60, 95% CI: 3.40-39.64, p<0.001) were predictive of the need for RA in multivariate analysis. Based on the regression coefficients, a scoring system was devised. The greater the score, the more likely a lesion required RA. The scoring system performed well in the external validation cohort, with 78% of patients crossing over having a score of greater than the proposed cut-off of 3.

CONCLUSIONS

We provide an angiographic scoring tool to support the expeditious use of time and resources, allowing assessment of the likelihood of success of a balloon-based strategy, or the necessity for RA.

High-speed rotational atherectomy in coronary artery calcification: The randomized ROTAXUS and PREPARE-CALC trials

BACKGROUND

The clinical outcomes of high-speed rotational atherectomy (RA) to optimize target lesion preparation in coronary artery calcification (CAC) have been examined in several trials.

AIMS

This study was conducted to evaluate the safety and efficacy of RA for CAC.

METHODS

Patient data were pooled from ROTAXUS and PREPARE-CALC. The primary endpoint was the in-stent late lumen loss and major adverse cardiac events (MACE) at 9 months. Secondary endpoints included in-segment late lumen loss, binary restenosis, strategy success, procedural duration, and contrast amount.

RESULTS

Four hundred and forty patients were enrolled from Germany in this study, 220 patients were randomized to the RA group and 220 patients were randomized to the Control group. Despite similar baseline characteristics, significantly more patients in the Control group were crossover (14.1% vs. 2.3%, p < 0.0001), resulting in higher strategy success in the RA group (95.0% vs. 82.3%, p < 0.0001). At 9 months, in-stent late lumen loss was higher in the RA group (0.34 ± 0.52 mm vs. 0.24 ± 0.47 mm, p = 0.03) and procedural duration was longer in the RA group (76.3 ± 41.8 min vs. 67.0 ± 38.8 min, p = 0.02). MACE (17.8% vs. 25.2%, p = 0.06), in-segment late lumen loss (0.28 ± 0.66 mm vs. 0.17 ± 0.55 mm, p = 0.05), binary restenosis (7.3% vs. 8.2%, p = 0.71 in-stent; 7.7% vs. 9.0%, p = 0.62 in-segment), and contrast amount (215.5 ± 112.5 ml vs. 203.7 ± 96.5 ml, p = 0.24) were similar in both groups.

CONCLUSION

Lesion preparation with upfront RA before drug-eluting stent implantation is feasible in CAC, is more strategy successful, and is associated with excessive in-stent late lumen loss and excellent clinical outcomes at 9 months although longer procedural duration.

Japan-USA orbital atherectomy for calcific coronary lesions: COAST study, Hharmonization by Doing proof-of-concept

Effective treatment strategies and medical devices continue to be needed in Japan and the United States of America (US) to mitigate the growing burden of cardiovascular disease and coronary heart disease. Unfortunately, there can be a delay in gaining cardiovascular device approval in Japan after a device has already been approved and is in use in the US. The Harmonization by Doing (HBD) program; however, can eliminate this delay and reduce the cost of completing a clinical trial in Japan. The HBD proof-of-concept study, COAST, resulted in approval of the Diamondback 360® Coronary Orbital Atherectomy System Micro Crown simultaneously in Japan and the US on the same day. Subsequently, the Diamondback 360® Coronary OAS Classic Crown also received approval in Japan. The COAST study provides further evidence that global clinical trials via HBD for medical devices are practical and advantageous.

Evaluation of the Safety and Efficacy of Coronary Intravascular Lithotripsy for Treatment of Severely Calcified Coronary Stenoses: Evidence From the Serial Disrupt CAD Trials

Background: Previous understanding holds that rotational atherectomy and modified balloons remain the default strategy for severely calcified coronary stenoses. In recent years, coronary intravascular lithotripsy (IVL) provides new ideas. This study was conducted to evaluate the safety and efficacy of IVL for the treatment of severely calcified coronary stenoses. Methods: The serial Disrupt CAD trials (Disrupt CAD I, Disrupt CAD II, Disrupt CAD III, and Disrupt CAD IV) were included in this study. The safety endpoint was freedom from major adverse cardiovascular events (MACE) in hospital, at 30 days, and at 6 months following the index procedure. The efficacy endpoints included procedural success and angiographic success. Optical coherence tomography (OCT) was used to evaluate the mechanism of action of IVL quantifying the coronary artery calcification (CAC) characteristics and calcium plaque fracture. Results: We enrolled a total of 628 patients with a mean age of 71.8 years, 77.1% males. In these patients, the left anterior descending artery and right coronary artery were the most vulnerable vessels. The diameter stenosis was 64.6 ± 11.6% and the lesion length was 24.2 ± 11.4 mm. IVL had a favorable efficacy (93.0% procedural success, 97.5% angiographic success, and 100.0% stent delivery). Among the 628 patients, 568, 568, and 60 reported MACE endpoints in hospital, at 30 days, and at 6 months, respectively. The results showed that 528, 514, and 55 patients were free from MACE in hospital, at 30 days, and at 6 months, respectively. OCT measurements demonstrated that calcium fracture was the underlying mechanism of action for coronary IVL. Conclusions: IVL is safe and efficient for severely calcified coronary stenoses, and, importantly, calcium fracture facilitated increased vessel compliance and favorable stent expansion.

Impact of chronic total occlusion lesions on clinical outcomes in patients receiving rotational atherectomy: results from the ROCK registry

The aim of this study was to investigate the impact of chronic total occlusion (CTO) on clinical outcomes in patients with calcified coronary lesions receiving rotational atherectomy (RA). This multi-center registry enrolled consecutive patients with calcified coronary artery disease who underwent RA during percutaneous coronary intervention (PCI) from 9 tertiary centers in Korea between January 2010 and October 2019. The primary outcome was target-vessel failure (TVF) which included the composite of cardiac death, target-vessel myocardial infarction (TVMI), and target-vessel revascularization (TVR). A total of 583 lesions were enrolled in this registry and classified as CTO (n = 42 lesions, 7.2%) and non-CTO (n = 541 lesions, 92.8%). The CTO group consisted of younger patients who were more likely to have a history of previous percutaneous coronary intervention or coronary artery bypass graft surgery. The incidence of the primary outcome was 14.1% and 16.7% for the non-CTO group and CTO group, respectively. The primary outcomes observed in the two groups were not significantly different (log-rank p = 0.736). The 18-month clinical outcomes of the CTO group were comparable to those of the non-CTO group in multivariate analysis. About 7% of patients requiring RA have CTO lesions and these patients experience similar clinical outcomes compared with those having non-CTO lesions. Use of RA for CTO lesions was safe despite higher procedural complexity.

Effect of Material and Population on the Delivery of Nanoparticles to an Atherosclerotic Plaque: A Patient-specific In Silico Study

Coronary artery disease (CAD) is the prevalent reason of mortality all around the world. Targeting CAD, specifically atherosclerosis, with controlled delivery of micro and nanoparticles, as drug carriers, is a very proficient approach. In this work, a patient-specific and realistic model of an atherosclerotic plaque in the left anterior descending (LAD) artery was created by image-processing of CT-scan images and implementing a finite-element mesh. Next, a fluid-solid interaction simulation considering the physiological boundary conditions was conducted. By considering the simulated force fields and particle-particle interactions, the correlation between injected particles at each cardiac cycle and the surface density of adhered particles over the atherosclerotic plaque (SDP) were examined. For large particles (800 and 1000 nm) the amount of SDP on the plaque increased significantly when the number of the injected particles became higher. However, by increasing the number of the injected particles, for the larger particles (800 and 1000 nm) the increase in SDP was about 50% greater than that of the smaller ones (400 and 600 nm). Furthermore, for constant number of particles, depending on their size, different trends in SDP were observed. Subsequently, the distribution and adhesion of metal-based nanoparticles including SiO₂, Fe₃O₄, NiO₂, silver and gold with different properties were simulated. The injection of metal particles with medium density among the considered particles resulted in the highest SDP. Remarkably, the affinity, the geometrical features, and the biophysical factors involved in the adhesion outweighed the effect of difference in the density of particles on the SDP. Finally, the consideration of the lift force in the simulations significantly reduced the SDP and consistently decreased the particle residence time in the studied domain.

Breaking the deadlock of calcified coronary artery lesions: A contemporary review

Percutaneous coronary intervention (PCI) of severely calcified lesions is known to result in lower procedural success rates, higher complication rates, and worse long-term clinical outcomes compared to noncalcified lesions. Adequate lesion preparation through calcium modification is crucial in ensuring procedural success and reducing adverse cardiovascular outcomes. There are numerous calcium modification devices currently available whose usefulness depends on the nature of the calcific disease and its anatomical distribution. It can be challenging for the interventionists to decide which device is best suited for their patient. There is also emerging evidence for intravascular imaging in guiding selection of calcium modification devices using parameters such as calcium distribution and depth that directly impact on procedural success and clinical outcomes. In this review we aim to discuss the pathophysiology of coronary calcification, evaluate strategies and technologies of calcium modification and propose an A-M-A-S-A algorithm in managing calcified coronary lesions.

Management of Calcific Coronary Artery Lesions: Is it Time to Change Our Interventional Therapeutic Approach?

Patients with obstructive coronary lesions with a high calcium content (LHCC) have an exaggerated clinical risk, because the presence of calcification is associated with more extensive coronary atheroma and higher burden of comorbidities. Treatment of LHCC using percutaneous techniques is complex because of an increased risk of incomplete lesion preparation with suboptimal stent deployment and higher rates of acute and chronic stent failure. Rotational atherectomy has been the predominant technology for treatment of high-grade LHCC, but novel devices/technologies have entered clinical practice. It seems likely that combining enhanced intravascular imaging, which allows definition of the patterns of calcification with these new technologies, will herald a change in procedural algorithms for treatment of LHCC. This review provides an overview about LHCC with special focus on existing and emergent technologies. We also provide a proposed procedural algorithm to facilitate optimal use of technology according to specific features of LHCC and coronary anatomy.

Active matter therapeutics

Nanotherapies based on micelles, liposomes, polymersomes, nanocapsules, magnetic nanoparticles, and noble metal nanoparticles have been at the forefront of drug delivery in the past few decades. Some of these nanopharmaceuticals have been commercially applied to treat a wide range of diseases, from dry eye syndrome to cancer. However, the majority involve particles that are passive, meaning that they do not change shape, and they lack motility; the static features can limit their therapeutic efficacy. In this review, we take a critical look at an emerging field that seeks to utilize active matter for therapeutics. In this context, active matter can be broadly referred to as micro or nanosized constructs that energetically react with their environment or external fields and translate, rotate, vibrate or change shape. Essentially, the recent literature suggests that such particles could significantly augment present-day drug delivery, by enhancing transport and increasing permeability across anatomical barriers by transporting drugs within solid tumor microenvironments or disrupting cardiovascular plaque. We discuss examples of such particles and link the transport and permeability properties of active matter to potential therapeutic applications in the context of two major diseases, namely cancer and heart disease. We also discuss potential challenges, opportunities, and translational hurdles.

Reappraisal Value of a Modified Rotational Atherectomy Technique in Contemporary Coronary Angioplasty Era

Objectives

To introduce a modified rotational atherectomy (RA) procedure and investigate the early and midterm outcomes of the RA-facilitating diversified percutaneous coronary intervention (PCI) in a large group of aged patients with higher cardiovascular risk.

Background

Previous studies about the outcomes of RA were limited with small sample size and low-risk population.

Methods

Between January 2013 and November 2015, 1169 consecutive patients treated with modified RA-facilitated PCI were retrospectively enrolled, including de novo calcified lesions and in-stent restenosis. Patients were regularly followed up for at least 1 year. Major adverse cardiac events (MACE) were analyzed for all participants by different strategies. Cox regression analysis was performed to identify risk factors for the events.

Results

The median age of patients was 75 years, with 11.7% of patients on maintenance hemodialysis. Most lesions (99.9%) were complex (American Heart Association type B2/C), and 68.3% were treated with RA + drug-eluting-stent (DES). Successful angiography was achieved in 97.8% cases, with 1.7% (20/1169) experiencing coronary perforation (including guidewire perforation). The incidence of MACE was 20.5% and 26.8% at 1-year and 2-year follow-up and were mainly driven by target lesion revascularization (TLR) (10.3% and 12.5%, respectively). The strategy of RA + DES had the lowest 2-year MACE, compared with the RA + drug-coated balloon and RA + plain old balloon angioplasty (14.5%, 30.5%, and 26.0%, respectively).

Conclusions

The modified RA technique is a safe and effective tool in the contemporary PCI era, even in high-risk patients. The TLR rate was relatively high but acceptable in such complex lesions.

Intracoronary Lithotripsy for the Treatment of Calcified Plaque

Intravascular lithotripsy facilitates percutaneous coronary intervention of lesions with severe calcification by using high-pressure ultrasonic energy. It is the newest adjunctive tool for calcium modification and is showing promise as its users gather more experience and it becomes readily available worldwide. This article reviews intravascular lithotripsy technology, the evidence in the literature, and the advantages and disadvantages compared with other forms of calcium modification, and discusses its role in specific subsets of coronary lesions. It concludes with a discussion about the future direction of research involving this new technology as its role within percutaneous cardiac procedures becomes more defined.

Calcific lesion preparation for coronary bifurcation stenting

Bifurcating coronary lesions are a very common challenge in interventional cardiology because of the technical complexity in their treatment, the risk of side branch occlusion and an overall worse outcome when compared to non-bifurcating lesions. The presence of calcifications represents further complexity due to the difficulty in device delivery and stent expansion as well as enhanced risk of side branch occlusion. Rotational and orbital atherectomy, scoring and cutting balloons, coronary lithoplasty are available tools which have been introduced over the last three decades to overcome such issue. Nevertheless, their application in different contexts of bifurcations presents specific caveats and the studies directed at comparing such techniques have never been expressly oriented in the subset of the bifurcating lesion. In this paper, we review these devices and their usefulness in bifurcations by analyzing consistent data from clinical trials, and we propose a practical algorithm for the treatment of severely calcified bifurcating lesions according to their anatomical features.

Catheter thermal energy generation and temperature in rotational atherectomy

This research studies the catheter friction thermal energy generation and saline temperature in rotational atherectomy (RA). RA is a catheter-based procedure utilizing a high-speed (typically 130,000 to 210,000 rpm) miniature grinding wheel to remove hardened calcified plaque inside the artery to restore the blood flow. During RA, elevated temperature due to the friction within the catheter may lead to complications such as slow-flow/no-reflow and myocardial infarction. RA experiments were conducted to measure the catheter temperature. An advection-diffusion model with inverse heat transfer solution was developed to estimate the spatial and temporal distributions of saline temperature and study effects of the rotational speed, catheter insertion length, and flow rates of blood-mimicking water and saline. The saline temperature rise is higher with higher wheel rotational speed, shorter insertion length, and lower flow rates of blood-mimicking water and saline. The wheel rotational speed and blood flow rate are the two most significant parameters affecting the saline and blood-mimicking water mixture temperature, which exhibits the highest (9 °C) rise under the 175,000 rpm wheel rotational speed and no blood-mimicking water flow (totally occluded artery) condition. This research provides insights and guidelines on RA device and clinical procedure from the thermal perspective.

Impact of calcification on percutaneous coronary intervention: MACE-Trial 1-year results

OBJECTIVES

The Multi-center Prospective Study to Evaluate Outcomes of Moderate to Severely Calcified Coronary Lesions (MACE-Trial) was designed to provide further insight on the impact of calcification on procedural and long-term percutaneous coronary intervention outcomes.

BACKGROUND

Prior studies evaluating the impact of lesion calcification on percutaneous coronary intervention outcomes are limited by: retrospective nature, pooled data from multiple studies, or lack of specificity around calcification with only operator assessment and without core lab evaluation.

METHODS

The MACE-Trial was a prospective, multicenter, observational clinical study that enrolled 350 subjects at 33 sites from September 2013 to September 2015. Core lab assessed subject stratification by lesion calcification (none/mild [N = 133], moderate [N = 99], and severe [N = 114]). Endpoints were lesion success, procedural success, and 1-year major adverse cardiac events (MACEs).

RESULTS

Presence of severe calcification had significant impact on lesion success ([83.3%] versus none/mild calcification [94.7%, P = 0.006]) and procedural success ([86.8%] versus moderate [95.0%, P = 0.028], and none/mild [97.7%, P = 0.001]). 1-year MACE rates were associated with presence of calcification in subjects with none/mild (4.7%), moderate (8.7%), and severe (24.4%) (P < 0.001) calcification; however, no difference was noted between none/mild and moderate (P = 0.237). The risk adjusted multivariable model identified severe calcification and decreasing eGFR as predictors of 30-day and 1-year MACE.

CONCLUSIONS

In this prospective study, patients with severe calcification had significantly worse outcomes compared to those without; however, unlike previous retrospective studies, moderate calcium resulted in similar outcomes as none/mild calcium.

CLINICAL TRIAL REGISTRATION

URL: https://clinicaltrials.gov/ct2/show/NCT01930214. Unique Identifier: NCT01930214.

Rotational Atherectomy in Acute STEMI with Heavily Calcified Culprit Lesion is a Rule Breaking Solution

BACKGROUND

Calcified coronary lesions represent technical challenges during percutaneous coronary intervention and are associated with a high frequency of restenosis and target lesion revascularization. Rotational atherectomy has been shown to increase procedural success in severely calcified lesions, facilitate stent delivery in undilatable lesions and ensure complete stent expansion. However, rotational atherectomy in ST-elevation Myocardial Infarction (STEMI) is traditionally avoided given the concern for slow or no reflow and considered a contraindication in lesions with a visible thrombus by its manufacturer (Rotablator, Boston Scientific).

CONCLUSION

This case demonstrates the successful use of rotational atherectomy to facilitate dilation and revascularization of a heavily calcified culprit lesions in a patient with acute anterior STEMI with ongoing chest pain.

Bailout rotational atherectomy in patients with myocardial infarction is not associated with an increased periprocedural complication rate or poorer angiographic outcomes in comparison to elective procedures (from the ORPKI Polish National Registry 2015-2016)

Introduction

Many years of experience and refinement of existing rotational atherectomy (RA) techniques have resulted in improved clinical outcomes and a tendency to broaden the spectrum of RA usage.

Aim

To compare the angiographic effectiveness and periprocedural complications in patients with stable angina (SA) and acute myocardial infarction (AMI) treated using RA.

Material and methods

Data were prospectively collected using the Polish Cardiovascular Intervention Society national registry (ORPKI) on all percutaneous coronary interventions (PCIs) performed in Poland in 2015 and 2016. In total, 975 RA procedures were recorded out of 221,187 PCI procedures.

Results

We compared angiographic effectiveness and periprocedural complications in 530 patients with SA and 245 with AMI in the RA group of patients, and 60,522 patients with SA and 91,985 with AMI in the non-RA group. The overall rate of periprocedural complications did not differ between SA and AMI patients in the RA group (2.3% vs. 2.0%; p = 0.84), while it was lower in AMI patients from the RA group compared to those from the non-RA group (2.0% vs. 3.0%; p = 0.34). The percentage of patients with angiographic success in the RA group was similar to the non-RA group in SA patients (97.3% vs. 97.1%; p = 0.75), whereas in the AMI group it was significantly higher compared to the non-RA group (96.7% vs. 92.6%; p < 0.001).

Conclusions

The angiographic effectiveness of PCI with RA in patients with AMI was not worse than in patients with SA.

Impact of Calcium on Chronic Total Occlusion Percutaneous Coronary Interventions

We sought to examine the impact of calcific deposits on the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The outcomes of 1,476 consecutive CTO PCIs performed in 1,453 patients (65.5 ± 10 years, 85% male) between 2012 and 2016 at 11 US centers were evaluated. Moderate or severe quantity of calcium was present in 58% of target lesions. Calcified lesions were more tortuous and more likely to have proximal cap ambiguity and interventional collaterals. PCI of moderately/severely calcified CTOs more often required use of the retrograde approach (54% vs 30%, p <0.001) and was associated with longer procedure and fluoroscopy time and higher air kerma radiation dose and contrast volume. Moderate/severe quantity of calcium was associated with lower technical (86.6% vs 93.8%, p <0.001) and procedural (84.4% vs 92.7%, p <0.001) success rates and higher incidence of major adverse cardiac events (3.7% vs 1.8%, p = 0.033). On multivariate analysis, the presence of moderate/severe quantity of calcium was not independently associated with technical success. Balloon angioplasty was the most common lesion preparation technique for calcified lesions, followed by rotational atherectomy and laser. To conclude, in a contemporary, multicenter registry, moderate/severe calcific deposits were present in 58% of attempted CTO lesions and were associated with higher use of the retrograde approach, lower success, and higher complication rates. However, on multivariable analysis, the amount of calcium was not independently associated with technical success.

Comparison of mid-term clinical outcomes between on-label and off-label use of rotational atherectomy

While rotational atherectomy (RA) is used for complex lesions in percutaneous coronary intervention, there are several contraindications such as unprotected left main stenosis or left ventricular dysfunction. We previously reported that the incidence of in-hospital complications was significantly greater in off-label as compared to on-label use RA. However, the mid-term clinical outcomes between off-label and on-label RA have not been investigated. The purpose of this study was to compare the mid-term clinical outcomes between off-label (n = 156) and on-label RA (n = 94). The primary endpoint was the incidence of major adverse cardiovascular events (MACE) defined as the composite of ischemia-driven target vessel revascularization (TVR), non-fatal MI, and all-cause death. We also identified 154 patients who underwent RA and follow-up angiography within 1 year, and compared quantitative coronary analysis between the off-label group (n = 96) and on-label group (n = 58). There was no significant difference in late luminal loss between the groups (0.03 ± 0.53 mm in the off-label and -0.05 ± 0.44 mm in the on-label groups, P = 0.57). However, the incidence of MACE was less in the on-label group (3.2 %) as compared to the off-label group (9.0 %) without reaching statistical significance (P = 0.08). In conclusion, mid-term clinical outcomes tended to be worse in the off-label group than in the on-label group. We may have to follow-up the patient who underwent off-label RA more carefully than the patient who underwent on-label RA.

Atherectomy Devices for the Treatment of Calcified Coronary Lesions

The presence of moderate and severe coronary artery calcification (CAC) is associated with higher rates of angiographic complications during percutaneous coronary intervention (PCI), as well as higher major adverse cardiac events compared with noncalcified lesions. Diabetes mellitus, a risk factor for CAC, is increasing in the United States. Vessel preparation before PCI with atherectomy can facilitate successful stent delivery and expansion that may otherwise not be possible. We review here CAC prevalence, risk factors, and impact on PCI, as well as the currently available coronary atherectomy devices including rotational atherectomy, orbital atherectomy, and laser atherectomy.

Safety and Efficacy of Immediate Rotational Atherectomy in Nondilatable Calcified Coronary Lesions Complicated by Coronary Artery Dissection (RAISE)

OBJECTIVES

To examine the safety and efficacy of immediate rotational atherectomy (RA) in nondilatable calcified coronary lesions complicated by coronary dissection during percutaneous coronary intervention (PCI).

BACKGROUND

In the presence of coronary dissection in nondilatable calcified coronary lesions, conservative management is suggested to permit the dissection to heal prior to treatment with RA. However, many patients have frequent angina attacks and some patients develop serious complications during this period.

METHODS

One hundred and nighty-eight patients with severe coronary calcification underwent PCI, and were randomized into immediate (n = 105) or delayed RA group (n = 93) when coronary dissections occur. The primary endpoint of the present study was all-cause death including cardiac and non-cardiac death in 4 years follow-up. Non-fatal myocardial infarction, stent thrombosis, cardiac tamponade, stroke, target lesion revascularization, New York Heart Association (NYHA) class IV heart failure were analyzed as secondary end points.

RESULTS

At a follow-up of 4 years, event-free survival rates were not statistically different between the immediate and delayed RA group (81.9% vs 80.6%, P = 0.820). Rates of PCI- and RA-related major adverse cardiac events (MACE) and severe RA-related complications were not statistically different between groups. Luminal loss was not significantly different between the immediate and delayed RA group as evaluated by Intravascular ultrasound (IVUS). Two cases in the delayed RA group experienced myocardial infarction during the 4-week waiting.

CONCLUSION

This study indicates that immediate RA during PCI is safe and effective in patients with coronary artery dissection.

Treatment of calcified coronary artery lesions

Heavily calcified coronary plaques represent a complex lesion subset and a challenge to the interventional cardiologist, as they are often resistant to simple plaque modification with conventional balloon angioplasty. Inadequate plaque modification can lead to stent underdeployment, which itself predisposes to in-stent restenosis and stent thrombosis. Over the years, a number of mechanical devices ranging from modified angioplasty balloons to atherectomy devices have become available in order to tackle such lesions. Here we review these devices concentrating on the evidence behind their use.

Classification of calcium in intravascular OCT images for the purpose of intervention planning

The presence of extensive calcification is a primary concern when planning and implementing a vascular percutaneous intervention such as stenting. If the balloon does not expand, the interventionalist must blindly apply high balloon pressure, use an atherectomy device, or abort the procedure. As part of a project to determine the ability of Intravascular Optical Coherence Tomography (IVOCT) to aid intervention planning, we developed a method for automatic classification of calcium in coronary IVOCT images. We developed an approach where plaque texture is modeled by the joint probability distribution of a bank of filter responses where the filter bank was chosen to reflect the qualitative characteristics of the calcium. This distribution is represented by the frequency histogram of filter response cluster centers. The trained algorithm was evaluated on independent ex-vivo image data accurately labeled using registered 3D microscopic cryo-image data which was used as ground truth. In this study, regions for extraction of sub-images (SI's) were selected by experts to include calcium, fibrous, or lipid tissues. We manually optimized algorithm parameters such as choice of filter bank, size of the dictionary, etc. Splitting samples into training and testing data, we achieved 5-fold cross validation calcium classification with F1 score of 93.7±2.7% with recall of ≥89% and a precision of ≥97% in this scenario with admittedly selective data. The automated algorithm performed in close-to-real-time (2.6 seconds per frame) suggesting possible on-line use. This promising preliminary study indicates that computational IVOCT might automatically identify calcium in IVOCT coronary artery images.

Two-Year Clinical Outcomes of Newer-Generation Drug-Eluting Stent Implantation Following Rotational Atherectomy for Heavily Calcified Lesions

BACKGROUND

Clinical outcomes of implantation of the newer-generation drug-eluting stent (DES) following rotational atherectomy for heavily calcified lesions remain unclear in the real-world setting.

METHODS AND RESULTS

We enrolled 252 consecutive patients (273 lesions) treated with newer-generation DES following rotational atherectomy. The primary endpoint was the cumulative 2-year incidence of major adverse cardiovascular events (MACE), defined as cardiac death, myocardial infarction, clinically-driven target lesion revascularization, and definite stent thrombosis. Complete clinical follow-up information at 2-year was obtained for all patients. The mean age was 73.2±9.0 years and 155 patients (61.5%) were male. Cumulative 2-year incidence of MACE (cardiac death, myocardial infarction, clinically-driven target lesion revascularization and definite stent thrombosis) was 20.3% (7.0%, 2.1%, 18.1% and 2.1%, respectively). Predictors of MACE were presenting with acute coronary syndrome (hazard ratio [HR]: 3.80, 95% confidence interval [CI]: 1.29-11.2, P=0.02), hemodialysis (HR: 1.93, 95% CI: 1.04-3.56, P=0.04) and previous coronary artery bypass graft (HR: 2.26, 95% CI: 1.02-5.00, P=0.045).

CONCLUSIONS

PCI for calcified lesions requiring rotational atherectomy is still challenging even in the era of newer-generation DES.

Rotational atherectomy: Technical update

Percutaneous coronary intervention is currently the most common form of revascularization for symptomatic coronary artery disease. In elderly, diabetic and renal patients, there is an increased prevalence of calcified coronary disease. Rotational atherectomy (RA) can be useful in the treatment of these lesions. Plaque removal was initially proposed as an alternative to balloon angioplasty, hence RA required high-velocity protocols with large-sized burrs (over 2.0 mm). With a high incidence of acute complications and disappointing restenosis rates, the use of RA dwindled. However, the advent of drug-eluting stents, which significantly decreased the rate of restenosis, led to the repositioning of RA as an adjunctive technique in the preparation of densely calcified lesions, improving stent delivery and expansion. In recent years, a better understanding of the mechanism of action of RA has changed it from a plaque debulking to a compliance modifying technique. As a result, RA has become less aggressive, using smaller size burrs and lower rotational speeds. This conservative approach has improved immediate results, with increased safety and better long-term outcomes. In this review paper, the technique of RA is explained in the light of current knowledge.