Rotational atherectomy does not reduce recurrent in-stent restenosis: results of the angioplasty versus rotational atherectomy for treatment of diffuse in-stent restenosis trial (ARTIST)

Calcified coronary lesions: Imaging, prognosis, preparation and treatment state of the art review

Calcific coronary artery stenosis is a complex disease associated with adverse outcomes and suboptimal percutaneous treatment. Calcium plaque modification has emerged as a key strategy to tackle the issues that accompany calcific stenosis - namely reduced device deliverability, unpredictable lesion characteristics, and difficult dilatation. Atherectomy has traditionally been the treatment modality of choice for heavily calcified coronary stenoses. Contemporary technologies have emerged to aid with planning, preparation, and treatment of calcified coronary stenosis in an attempt to improve procedural success and long-term outcomes. In this State Of The Art Review, we synthesize the body of data surrounding the diagnosis, imaging, and treatment of calcific coronary disease, with a focus on i) intravascular imaging, ii) calcific lesion preparation, iii) treatment modalities including atherectomy, and iv) updated treatment algorithms for the management of calcified coronary stenosis.

Current Management of In-Stent Restenosis

In-stent restenosis (ISR) remains the primary cause of target lesion failure following percutaneous coronary intervention (PCI), resulting in 10-year incidences of target lesion revascularization at a rate of approximately 20%. The treatment of ISR is challenging due to its inherent propensity for recurrence and varying susceptibility to available strategies, influenced by a complex interplay between clinical and lesion-specific conditions. Given the multiple mechanisms contributing to the development of ISR, proper identification of the underlying substrate, especially by using intravascular imaging, becomes pivotal as it can indicate distinct therapeutic requirements. Among standalone treatments, drug-coated balloon (DCB) angioplasty and drug-eluting stent (DES) implantation have been the most effective. The main advantage of a DCB-based approach is the avoidance of an additional metallic layer, which may otherwise enhance neointimal hyperplasia, provide the substratum for developing neoatherosclerosis, and expose the patient to a persistently higher risk of coronary ischemic events. On the other hand, target vessel scaffolding by DES implantation confers relevant mechanical advantages over DCB angioplasty, generally resulting in larger luminal gain, while drug elution from the stent surface ensures the inhibition of neointimal hyperplasia. Nevertheless, repeat stenting with DES also implies an additional permanent metallic layer that may reiterate and promote the mechanisms leading to ISR. Against this background, the selection of either DCB or DES on a patient- and lesion-specific basis as well as the implementation of adjuvant treatments, including cutting/scoring balloons, intravascular lithotripsy, and rotational atherectomy, hold the potential to improve the effectiveness of ISR treatment over time. In this review, we comprehensively assessed the available evidence from randomized trials to define contemporary interventional treatment of ISR and provide insights for future directions.

Comparative efficacy of interventional therapies and devices for coronary in-stent restenosis: A systematic review and network meta-analysis of randomized controlled trials

Background

In-stent restenosis (ISR) has become a significant obstacle to interventional therapy for atherosclerotic cardiovascular disease. The optimal percutaneous coronary intervention (PCI) strategy for patients with coronary ISR remains controversial. This network meta-analysis (NMA) was aimed to compare and estimate the effectiveness of different PCI strategies and commercial devices for the treatment of patients with coronary ISR.

Methods

In present study, we systematically searched PubMed, Embase, Web of Science, and Cochrane Library from database inception to October 20, 2022, to identify randomized controlled trials. We included studies comparing various PCI strategies for the treatment of any type of coronary ISR. The study was registered with PROSPERO, CRD 42022364308.

Results

We included 44 eligible trials including 8479 patients, 39 trials comparing the treatment effects of 10 PCIs, and 5 trials comparing the efficacy between different types of drug-eluting stent (DES) or drug-coated balloon (DCB) devices. Among the PCIs, everolimus-eluting stent was the optimal strategy considering target lesion revascularization (TLR), percent diameter stenosis (%DS), and binary restenosis (BR), and sirolimus-coated balloon was the optimal strategy considering late lumen loss (LLL). In the comparison of commercial devices, the combination strategy excimer laser coronary angioplasty plus SeQuent Please paclitaxel-coated balloon showed promising therapeutic prospects.

Conclusions

DCB and DES remain the preferred treatment strategies for coronary ISR, considering both the primary clinical outcome (TLR) and the angiographic outcomes (LLL, BR, %DS). Personalized combination interventions including DCB or DES hold promise as a novel potential treatment pattern for coronary ISR.

SCAI Expert Consensus Statement on the Management of Calcified Coronary Lesions

The prevalence of calcification in obstructive coronary artery disease is on the rise. Percutaneous coronary intervention of these calcified lesions is associated with increased short-term and long-term risks. To optimize percutaneous coronary intervention results, there is an expanding array of treatment modalities geared toward calcium modification prior to stent implantation. The Society for Cardiovascular Angiography and Interventions, herein, puts forth an expert consensus document regarding methods to identify types of calcified coronary lesions, a central algorithm to help guide use of the various calcium modification strategies, tips for when using each treatment modality, and a look at future studies and trials for treating this challenging lesion subset.

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.

Gallic Acid Inhibits Proliferation and Migration of Smooth Muscle Cells in a Pig In-Stent Restenosis Model

In-stent restenosis (ISR) develops primarily due to neointimal hyperplasia. Gallic acid (GA) has anti-inflammatory, antioxidant, and cardioprotective effects. This study sought to investigate the effects of GA on neointimal hyperplasia and proliferation and migration of vascular smooth muscle cells (VSMCs) in a pig ISR model. In vitro proliferation and migration experiments were confirmed, after VSMCs were treated with platelet-derived growth factor (PDGF-BB) and GA (100 µM) using a 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay and a scratch wound assay for 24 hours and 48 hours. A bare metal stent (BMS) was implanted in the pig coronary artery to induce ISR with overdilation (1.1-1.2:1), and GA (10 mg/kg/day) was administered for 4 weeks. At the 4-week follow-up, optical coherence tomography (OCT) and histopathological analyses were performed. GA decreased the proliferation of VSMCs by PDGF-BB for 24 hours (89.24±24.56% vs. 170.04±19.98%, p<0.001) and 48 hours (124.87±7.35% vs. 187.64±4.83%, p<0.001). GA inhibited the migration of VSMCs induced by PDGF-BB for 24 hours (26.73±2.38% vs. 65.38±9.73%, p<0.001) and 48 hours (32.96±3.04% vs. 77.04±10.07%, p<0.001). Using OCT, % neointimal hyperplasia was shown to have significantly decreased in the GA group compared with control vehicle group (28.25±10.07% vs. 37.60±10.84%, p<0.001). GA effectively reduced neointimal hyperplasia by inhibiting the proliferation and migration of VSMCs in a pig ISR model. GA could be a potential treatment strategy for reducing ISR after stent implantation.

Systematic Review of the Efficacy of Orbital Atherectomy in Improving the Outcome of Percutaneous Corornary Intervention in People With Diabetes

The optimal approach to deal with severe coronary artery calcification (CAC) in people with diabetes remains ill-defined. People with diabetes have a significant risk of developing severe vessel calcification and coronary artery disease (CAD). CAD is the leading cause of death in people with diabetes. Individuals with diabetes mainly present with severe multivessel stenosis, diffuse coronary calcification, and severe atherosclerosis, which are poor prognostic factors of revascularization procedures. Studies have shown that the revascularization of arteries in people with diabetes often results in worse outcomes than in people without diabetes. Coronary artery bypass grafting (CABG) has been recommended as the standard of care for people with DM and complex anatomic diseases, including left main CAD. However, percutaneous coronary intervention (PCI) is more acceptable to patients in clinical practice because of decreased trauma and rapid recovery. Severe CAC has traditionally been challenging for PCI and a frequent indication for surgical revascularization. This study aims to determine the effectiveness of orbital atherectomy (OA) in improving PCI outcomes in patients with diabetes and identify possible adverse effects that preclude its use.  The study is reported according to PRISMA and analyzed according to Cochrane guidelines on synthesis without meta-analysis. A comprehensive literature search of EMBASE, Scopus, Web of Science, Cochrane Library, CINAHL, and MEDLINE was conducted for studies that utilized OA before PCI in people with diabetes. A reference list of the eligible articles was also screened. A narrative synthesis was done by representing the data on the effect direction plot, followed by vote counting. Eighteen studies were included in the analysis. Success rate/successful stent delivery was >90%, while freedom from angiographic complication and major adverse cardiovascular and cerebrovascular events (MACCE) were both >80% on the effect direction plot for people with diabetes and those without diabetes. People with diabetes had low event rates similar to those without diabetes. OA appears to be a viable treatment approach for people with diabetes. However, RCTs with a longer duration of follow-up are required to establish the appropriate treatment strategy for severe CAC in people with diabetes.

Clinical outcomes of coronary intravascular lithotripsy in patients with stent failure (COIL registry)

BACKGROUND

Intravascular lithotripsy (IVL) has been demonstrated to be an effective treatment of calcified de novo coronary lesions. Safety data on the use of IVL within stented segments are lacking. We sought to evaluate the safety, feasibility, and long-term outcomes of IVL in patients with stent failure.

METHODS

This was a retrospective multi-centre registry that included consecutive patients with stent failure who had undergone IVL treatment. The primary efficacy endpoint was procedural success defined as residual stenosis <30% (determined by quantitative coronary angiography analysis) in patients who survived hospital admission without in-hospital adverse events. Major adverse cardiovascular events (MACE) were defined as the composite endpoints of cardiovascular death, spontaneous myocardial infarction, and target vessel revascularisation at one-year follow up.

RESULTS

102 patients were included in this study. Mean age was 73 ± 9 years and 81% were male. The duration from previous stent implantation and IVL treatment was 24 (interquartile range 7-76) months, of which 10.8% received IVL for acute under-expanded stent. IVL treatment allowed significant improvement in both minimal lumen diameter (1.14 ± 0.60 to 2.53 ± 0.59, P < 0.001) and degree of stenosis (66.8 ± 19.9 to 20.3 ± 11.3%, P < 0.001). The rate of procedural success was 78.4% (80/102 of patients). The one-year MACE was 15.7%. Ostial disease (HR 5.16; 95% CI 1.19 to 22.33; P = 0.028) and lesion length (HR 1.05; 95% CI 1.01 to 1.10; P = 0.010) were independently associated with one-year MACE.

CONCLUSIONS

In patients with stent failure, IVL is a safe and feasible treatment for this high-risk group.

Rotational Atherectomy Versus Intravascular Lithotripsy for Calcified In-Stent Restenosis: A Single-Center Study With 1-Year Follow-Up

Although rotational atherectomy (RA) and intravascular lithotripsy (IVL) have been proved to be effective for calcified de novo coronary lesions, their use in patients with in-stent restenosis (ISR) is still controversial. No comparison of these techniques in patients with ISR has been published so far. We sought to evaluate safety and feasibility of RA and IVL in patients with calcified ISR. Furthermore, we aimed to compare in-hospital and 1-year clinical outcomes between both groups. This is a retrospective single-center study evaluating patients with calcified ISR treated with RA (between 2012 and 2021) and IVL (between 2019 and 2021). Inhospital and 1-year clinical outcomes were compared between IVL and RA patients. In total, 28 patients with ISR who underwent RA were compared with 24 ISR subjects after IVL. The procedural success rate was 100% in both the groups. Quantitative coronary analysis demonstrated a similar degree of stenosis prior (66.4 ± 11.4 vs 68.8 ± 19.7, p = nonsignificant [NS]), and after the procedure (21.5 ± 20.5 vs 22.8 ± 12.1, p = NS) with no difference in acute luminal gain (1.34 ± 0.60 vs 1.38 ± 0.59, p = NS). There was one in-hospital major adverse cardiovascular event in the RA group. At 1-year follow-up, no difference was observed with respect to major adverse cardiovascular event rate (14.3% vs 16.7%, p = NS) and target vessel revascularization (7.1% vs 12.5%, p = NS). In conclusion, RA and IVL are safe and feasible techniques for calcified ISR yielding comparable results at 1-year follow-up. Further clinical studies are warranted to confirm our findings and shed more light on patient and lesion characteristics associated with the best outcomes.

SCAI Expert Consensus Statement on Management of In-Stent Restenosis and Stent Thrombosis

Stent failure remains the major drawback to the use of coronary stents as a revascularization strategy. Recent advances in imaging have substantially improved our understanding of the mechanisms underlying these occurrences, which have in common numerous clinical risk factors and mechanical elements at the time of stent implantation. In-stent restenosis remains a common clinical problem despite numerous improvements in-stent design and polymer coatings over the past 2 decades. It generates significant health care cost and is associated with an increased risk of death and rehospitalization. Stent thrombosis causes abrupt closure of the stented artery and therefore carries a high risk of myocardial infarction and death. This Society for Cardiovascular Angiography & Interventions (SCAI) Expert Consensus Statement suggests updated practical algorithmic approaches to in-stent restenosis and stent thrombosis. A pragmatic outline of assessment and management of patients presenting with stent failure is presented. A new SCAI classification that is time-sensitive with mechanistic implications of in-stent restenosis is proposed. Emphasis is placed on frequent use of intracoronary imaging and assessment of timing to determine the precise etiology because that information is crucial to guide selection of the best treatment option. SCAI recommends image-guided coronary stenting at the time of initial implantation to minimize the occurrence of stent failure. When in-stent restenosis and stent thrombosis are encountered, imaging should be strongly considered to optimize the subsequent approach.

Biomarkers Associated with Immune Checkpoint, N6-Methyladenosine, and Ferroptosis in Patients with Restenosis

Purpose

This study aimed to identify potential diagnostic markers of restenosis after stent implantation and to determine their association with immune checkpoint, ferroptosis, and N6-methyladenosine (m6A).

Patients and methods

Microarray data were downloaded from the National Center for Biotechnology Information (NCBI: GSE46560 and GSE48060 datasets) to identify differentially expressed genes (DEGs) between in-stent restenosis and no-restenosis samples. We then conducted systematic functional enrichment analyses of the DEGs based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), and further predicted the interactions of different proteins using the Search Tool for the Retrieval of Interacting Genes (STRING). We used the MCC and MCODE algorithms in the cytoHubba plug-in to screen three key genes in the network, and employed receiver operating characteristic (ROC) curves to determine their diagnostic significance using a multiscale curvature classification algorithm. Next, we investigated the relationships between these target genes, immune checkpoint, ferroptosis, and m6A. Finally, quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the above results.

Results

We identified 62 upregulated genes and 243 downregulated genes. Based on GO, KEGG, and screening results, EEF1D, RPL36, and RPSA are promising genes for predicting restenosis. In addition, the methylation of YTHDF2, the ferroptosis-related gene GLS2, and the immune checkpoint-related gene CTLA4 were observed to be associated with restenosis. The qRT-PCR test confirmed that RPSA and RPL36 are useful diagnostic markers of the restenosis that can provide new insights for future studies on its occurrence and molecular mechanisms.

Conclusion

We found that RPSA and RPL36, as useful diagnostic markers of restenosis, can provide new insights for future studies on its occurrence and molecular mechanisms.

Contemporary percutaneous management of coronary calcification: current status and future directions

Severe coronary artery calcification is one of the greatest challenges in attaining success in percutaneous coronary intervention, limiting acute and long-term results. In many cases, plaque preparation is a critical prerequisite for delivery of devices across calcific stenoses and also to achieve adequate luminal dimensions. Recent advances in intracoronary imaging and adjunctive technologies now allow the operator to select the most appropriate strategy in each individual case. In this review, we will revisit the distinct advantages of a complete assessment of coronary artery calcification with imaging and application of appropriate and contemporary plaque modification technologies in achieving durable results in this complex lesion subset.

Intravascular Imaging for Guiding In-Stent Restenosis and Stent Thrombosis Therapy

Advances in stent technology and the design of endovascular devices with thinner struts, anti-inflammatory and antithrombotic polymers, and better drug kinetics have enhanced the safety and efficacy of the second-generation drug-eluting stents and broadened their use in the therapy of high-risk patients and complex anatomies. However, despite these developments, in-stent restenosis and stent thrombosis remain the Achilles' heel of percutaneous coronary intervention, with their cumulative incidence reaching up to 10% at 5 years following percutaneous coronary intervention. The treatment of stent failure poses challenges and is associated with a worse prognosis than conventional percutaneous coronary intervention. Several studies have recently highlighted the value of intravascular imaging in identifying causes of stent failure, underscored its role in treatment planning, and registries have shown that its use may be associated with better clinical outcomes. The present review aims to summarize the evidence in the field; it discusses the value of intravascular imaging in identifying the mechanisms of in-stent restenosis and stent thrombosis in assessing the morphological characteristics of neointima tissue that appears to determine long-term outcomes in evaluating procedural results, and presents the findings of studies supporting its value in guiding therapy in stent failure.

Contemporary Management of Severely Calcified Coronary Lesions

Coronary artery calcification is increasingly prevalent in our patient population. It significantly limits the procedural success of percutaneous coronary intervention and is associated with a higher risk of adverse cardiovascular events both in the short-term and long-term. There are several modalities for modifying calcified plaque, such as balloon angioplasty (including specialty balloons), coronary atheroablative therapy (rotational, orbital, and laser atherectomy), and intravascular lithotripsy. We discuss each modality’s relative advantages and disadvantages and the data supporting their use. This review also highlights the importance of intravascular imaging to characterize coronary calcification and presents an algorithm to tailor the calcium modification therapy based on specific coronary lesion characteristics.

In-Stent Restenosis

In-stent restenosis (ISR) remains a potential complication after percutaneous coronary intervention, even in the era of drug-eluting stents, and its treatment remains suboptimal. Neoatherosclerosis is an important component of the pathology of ISR and is accelerated in drug-eluting stents compared with bare-metal stents. Coronary angiography is the gold standard for evaluating the morphology of ISR, although computed tomography angiography is emerging as an alternative noninvasive modality to evaluate the presence of ISR. Drug-coated balloons and stent reimplantation are the current mainstays of treatment for ISR, and the choice of treatment should be based on clinical background and lesion morphology.

Coronary In-Stent Restenosis: JACC State-of-the-Art Review

The introduction and subsequent iterations of drug-eluting stent technologies have substantially improved the efficacy and safety of percutaneous coronary interventions. However, the incidence of in-stent restenosis (ISR) and the resultant need for repeated revascularization still occur at a rate of 1%-2% per year. Given that millions of drug-eluting stents are implanted each year around the globe, ISR can be considered as a pathologic entity of public health significance. The mechanisms of ISR are multifactorial. Since the first description of the angiographic patterns of ISR, the advent of intracoronary imaging has further elucidated the mechanisms and patterns of ISR. The armamentarium and treatment strategies of ISR have also evolved over time. Currently, an individualized approach using intracoronary imaging to characterize the underlying substrate of ISR is recommended. In this paper, we comprehensively reviewed the incidence, mechanisms, and imaging characterization of ISR and propose a contemporary treatment algorithm.

Safety and Feasibility of Rotational Atherectomy for Retrograde Recanalization of Chronically Occluded Coronary Arteries

Objective

To evaluate the safety and feasibility of rotational atherectomy (RA) in retrograde chronic total occlusion percutaneous coronary intervention (CTO-PCI) by analyzing immediate and long-term outcomes.

Background

Recent evidence supports the safety and feasibility of RA in CTO-PCI. However, few studies have focused on the use of RA in a retrograde approach to percutaneous revascularization of chronic total occlusion (CTO) lesions and information on long-term outcomes is lacking.

Methods

A total of 329 patients who underwent retrograde CTO-PCI, out of 1496 consecutive CTO-PCI patients from April 2017 to July 2020, were retrospectively recruited from the 2nd Cardiology Department of the Guangdong Provincial People's Hospital. 16 patients underwent RA (RA group) whilst 313 did not (non-RA group).

Results

Technical (87.5% vs. 87.5) and procedural (85.9% vs. 87.5) success rates were similar between both groups. There was no difference concerning major procedural complications between groups (12.5% vs. 19.2%; p &gt; 0.75). No in-hospital MACCEs was recorded in the RA group while there were eight MACCEs in the non-RA group (p &gt; 0.99). In the RA group, 2 cases recorded perforation (1 target vessel perforation case and 1 branch vessel perforation), and 55 cases of vessel perforations/dissections were recorded in non-RA group including 18 target vessel perforations, 2 branch vessel perforations, 35 collateral vessel perforations (one patient died from cardiac tamponade). No difference was found in terms of the perforation rate between the two groups (p &gt; 0.99). Over a mean follow-up period of 26.47 ± 14.46 months, use of RA in retrograde CTO-PCI did not result in an increased mortality rate [hazard ratio (HR) 1.58, 95% confidence interval (CI), 0.31–8.21, p = 0.65], major adverse cardiac and cerebral events (HR 0.99, 95% CI 0.35–2.79, p = 0.99) or overall rehospitalization rate (HR 1.27, 95% CI 0.44–3.67, p = 0.67). Adjusted Kaplan–Meier curves according to Cox regression model suggested several predictors influencing the all-cause mortality, cardiovascular mortality, MACCEs, stroke rate, non-fatal myocardial infarction, target vessel recanalization rate and rehospitalization rate in the comparison.

Conclusions

Our study demonstrates that the in-hospital outcomes and long-term follow up events were the same between RA and non-RA retrograde CTO-PCI patients. RA offered an option for skillful operators in difficult cases when the lesion was severely calcified in retrograde CTO-PCI.

Management of in-stent restenosis

In-stent restenosis (ISR) remains the most common cause of stent failure after percutaneous coronary intervention (PCI). Recent data suggest that ISR-PCI accounts for 5-10% of all PCI procedures performed in current clinical practice. This State-of-the-Art review will primarily focus on the management of ISR but will begin by briefly discussing diagnosis and classification. We then move on to detail the evidence base underpinning the various therapeutic strategies for ISR before finishing with a proposed ISR management algorithm based on current scientific data.

In Stent Neo-Atherosclerosis: Pathophysiology, Clinical Implications, Prevention, and Therapeutic Approaches

Despite the dramatic improvements of revascularization therapies occurring in the past decades, a relevant percentage of patients treated with percutaneous coronary intervention (PCI) still develops stent failure due to neo-atherosclerosis (NA). This histopathological phenomenon following stent implantation represents the substrate for late in-stent restenosis (ISR) and late stent thrombosis (ST), with a significant impact on patient’s long-term clinical outcomes. This appears even more remarkable in the setting of drug-eluting stent implantation, where the substantial delay in vascular healing because of the released anti-proliferative agents might increase the occurrence of this complication. Since the underlying pathophysiological mechanisms of NA diverge from native atherosclerosis and early ISR, intra-coronary imaging techniques are crucial for its early detection, providing a proper in vivo assessment of both neo-intimal plaque composition and peri-strut structures. Furthermore, different strategies for NA prevention and treatment have been proposed, including tailored pharmacological therapies as well as specific invasive tools. Considering the increasing population undergoing PCI with drug-eluting stents (DES), this review aims to provide an updated overview of the most recent evidence regarding NA, discussing pathophysiology, contemporary intravascular imaging techniques, and well-established and experimental invasive and pharmacological treatment strategies.

[Focus on high speed rotational atherectomy by Rotablator in 2021 and datas from France PCI registry]

Developed in the late 1980s, rotational atherectomy has raised a lot of hope for its innovative principle of selective ablation, allowing volume reduction (instead of redistribution) of atherosclerotic plaque, while sparing healthy tissue. Long shunned for its disappointing results on restenosis, the Rotablator finally reasserted itself in the 2000s; era of drug eluting stents and coronary angioplasty boom, thus generating emergence of complex lesions. Indeed, the Rotablator has demonstrated an undeniable benefit in complex (type C) and calcified lesions preparation (before stenting), with a procedural success rate of 95%. Although these lesions only represent a small amount (2-3%) of percutaneous coronary interventions (PCI), they remain a technical impasse for plain-old balloon angioplasty strategy, making the Rotablator more suitable for these resistant lesions' treatment. Registry data attest the safety of this therapy, with a rate of peri-procedural complications and in-hospital mortality comparable to conventional angioplasty (France PCI register). However, certain specific, rare but serious complications (burr entrapment, broken Rotawire, coronary perforation) justify trained teams, perfect knowledge of the equipment, and strict compliance with good practice guidelines. In 2018, the rise of a new method of atherectomy by intra-vascular lithotripsy (Shockwave) has coincided with Rotablator decreasing activity (this finding being biased by a general decrease in PCI activity due to Covid pandemic). This therapeutic range's enhancement revolutionizes calcified lesions treatment, tending towards precise targeting of each indication, depending in particular on calcium distribution's anatomy in the plaque.

Additional ablation effect of low-speed rotational atherectomy following high-speed rotational atherectomy on early calcified in-stent restenosis: A case report

Optical frequency domain imaging-guided additional low-speed rotational atherectomy following sufficient high-speed rotational atherectomy for early calcified in-stent restenosis might be a safe and useful option for achieving additional large lumen gains and stent expansion.

Between a rock and a hard place: Orbital atherectomy for under-expanded stents

Stent under-expansion (rather than intimal hyperplasia) may be the cause of in-stent restenosis. Later expansion of coronary stents that were not fully deployed initially, can be difficult. Atherectomy is one method of facilitating late stent expansion, but too few patients have been treated to determine the risk benefit ratio.

Feasibility of intravascular lithotripsy for calcific coronary lesions: A multi-institutional experience

OBJECTIVE

We sought to determine the safety and performance of intravascular lithotripsy in the treatment of severe calcified atherosclerotic lesions.

BACKGROUND

The modification of severe calcified atherosclerotic lesions with noncompliant or specialty balloons, as well as orbital or rotational atherectomy has limitations and may be ineffective, increasing the risk of periprocedural complications and worsening long-term results. Intravascular lithotripsy has recently been shown to be a safe and feasible alternative to the above methods.

METHODS

All consecutive patients treated with Shockwave Medical Intravascular Lithotripsy (S-IVL) between May 2019 and June 2020 were included in current analysis. Device safety and efficacy were the critical endpoints of the study. The primary safety endpoint was 30-day major adverse cardiac events (MACE). In turn, device and clinical success were the primary performance endpoints.

RESULTS

In total, 46 patients undergoing percutaneous coronary intervention were treated with S-IVL before stent deployment (65% male; age, 71 ± 7 years). Device success was achieved in 45 (97.8%) patients with reduction of diameter stenosis from 80% to 5.2% with an acute gain of 2.5 mm. Clinical success was demonstrated in 95.6% of cases. During the 30-day follow-up, one sudden death was recorded, regarded as probable subacute stent thrombosis. During 6-month follow up one target lesion and target vessel revascularizations occurred. The rate of MACE after 6 month was 6.2%.

CONCLUSIONS

S-IVL appears to be a safe and effective treatment modality in coronary calcium modification to optimize stent expansion. In selected cases this device obviates the need for more complex lesion preparation strategies such as atherectomy.

Procedural and 1-year clinical outcomes of orbital atherectomy for treatment of coronary in-stent restenosis: A single-center, retrospective study

OBJECTIVES

We evaluated the procedural and 1-year clinical outcomes of orbital atherectomy (OA) for treatment of coronary in-stent restenosis (ISR).

BACKGROUND

The optimal treatment for ISR remains uncertain. While rotational and laser atherectomy have been used as neointimal debulking techniques for ISR, there have been few reports on OA for ISR.

METHODS

This is a retrospective observational study of consecutive patients who underwent percutaneous coronary intervention (PCI) for ISR with OA in Mount Sinai catheterization laboratory between November 2013 and January 2018. Procedural success was defined as angiographic success without in-hospital major adverse cardiac events (MACE; the composite of all-cause death, myocardial infarction [MI], or target vessel revascularization). Clinical outcomes were assessed at 1 month and 12 months postprocedure.

RESULTS

A total of 87 patients were included in the study. All 87 patients were treated with OA, after which 49 (56.3%) patients also received new drug-eluting stents. Angiographic success was achieved in 87 (100%) patients and procedural success was achieved in 79 (90.8%) patients. In-hospital MACE occurred in 8 (9.2%) patients, all due to periprocedural non-Q-wave MI. Acute lumen gain was 1.19 ± 0.57 mm after OA plus balloon angioplasty and 1.75 ± 0.50 mm after stent placement. MACE within 1 year occurred in 17 (19.5%) patients.

CONCLUSIONS

OA for ISR was performed with favorable procedural and 1-year clinical outcomes. Randomized trials are warranted to determine whether OA improves the poor prognosis of patients with ISR treated without debulking.

Risk prediction of in-stent restenosis among patients with coronary drug-eluting stents: current clinical approaches and challenges

Introduction: In-stent restenosis (ISR) has been one of the biggest limitations to the success of percutaneous coronary intervention for the treatment of coronary artery disease (CAD). The introduction of drug-eluting stent (DES) was a revolution in the treatment of CAD because these devices drastically reduced ISR to very low levels (<5%). Subsequently, newer generation DES treatments have overcome the drawbacks of first-generation DES, i.e. delayed endothelialization, and late stent thrombosis. However, the issue of late ISR, including neoatherosclerosis after DES implantation especially in high-risk patients and complex lesions, still exists as a challenge to be overcome.Areas covered: We discuss the mechanisms of ISR development including neoatherosclerosis, past and current clinical status of ISR, and methods to predict and overcome this issue from pathological and clinical points of view.Expert opinion: The initial drawbacks of first-generation DES, such as delayed endothelial healing and subsequent risk of late stent thrombosis, have been improved upon by the current generation DES. To achieve better long-term clinical outcomes, further titration of drug-release and polymer degradation profile, strut thickness as well as material innovation are needed.

Outcome of endovascular recanalization for intracranial in-stent restenosis

BACKGROUND AND PURPOSE

In-stent restenosis (ISR) is one of the long-term adverse outcomes of endovascular angioplasty and stenting for symptomatic intracranial arterial stenosis. In this study, we try to evaluate the safety and efficacy of endovascular treatment for intracranial ISR.

METHODS

We retrospectively collected patients with intracranial ISR who underwent endovascular treatment from June 2012 to August 2019 at a high-volume stroke center. Successful recanalization was defined as ≤30% residual stenosis. Stroke, myocardial infarction, and death after stenting within 30 days were used to evaluate periprocedural safety. Recurrent stroke in the territory of the culprit vessel and re-ISR in patients with clinical and vascular imaging follow-up data were used to evaluate the long-term outcome.

RESULTS

32 patients (59.6±7.2 years old) with ISR were recruited, including 22 patients (68.8%) treated with balloon dilatation, 8 patients (25%) with stenting, and 2 patients (6.3%) with failed procedures. Successful recanalization was achieved in 71.9% (23/32) of patients. There was no stroke, myocardial infarction or death within 30 days after the procedure. Recurrent stroke was found in 10.7% (3/28) of the patients, and re-ISR was found in 42.1% (8/19) of the patients. The re-ISR rate was lower in patients with stenting than in those with balloon dilatation (0% vs 57.1%, p=0.090), and in patients with successful recanalization than in those with unsuccessful recanalization (33.3% vs 75.0%, p=0.352), but with no statistically significant difference.

CONCLUSIONS

The periprocedural safety of endovascular treatment for intracranial ISR may be acceptable, but the long-term rates of recurrent stroke and re-ISR remain at high levels.

Predictive value of the geriatric nutritional risk index in percutaneous coronary intervention with rotational atherectomy

The prognostic value of the geriatric nutritional risk index (GNRI) in patients undergoing percutaneous coronary intervention (PCI) with rotational atherectomy (RA) remains unknown. Therefore, we aimed to clarify whether the GNRI could predict major adverse cardiac events (MACE) in patients undergoing PCI with RA. A total of 206 patients who underwent PCI with RA from January 2009 to December 2017 were retrospectively tracked. The patients were divided into 2 groups based on the GNRI value on admission. MACE comprised all-cause death, target lesion revascularization (TLR), target vessel revascularization (TVR), and myocardial infarction. One year of follow up was completed in 95.6% of patients. During this period, 50 cases of MACE were observed (all-cause death, 32 cases; TLR, 21 cases; and TVR, 2 cases). Patients with a low GNRI (< 98) had a significantly higher incidence of MACE than did patients with a high GNRI (≥ 98) (37.9% vs. 15.5%, log-rank p < 0.05). The GNRI was an independent predictor of MACE (hazard ratio, 0.94; 95% confidence interval [CI], 0.92-0.97). Furthermore, the GNRI had better predictive power than did its components alone (i.e. body mass index and serum albumin level) (net-reclassification improvement, 0.39; 95% CI, 0.07-0.71; p = 0.01; integrated discrimination improvement, 0.02; 95% CI, - 0.01-0.04; p = 0.07). The GNRI on admission is a predictor of MACE after PCI with RA. Further studies are required to determine whether intensive medical therapy could improve clinical events, particularly cardiovascular death and revascularization, in this population.

Halfway rotational atherectomy for calcified lesions: Comparison with conventional rotational atherectomy in a propensity-score matched analysis

Background

The incidence of severe complications such as burr entrapment or perforation is considerable with rotational atherectomy (RA). Halfway RA is a novel strategy, in which an operator does not advance the burr to the end of a continuous calcified lesion, and performs balloon dilatation to treat the remaining part of the calcified lesion. The purpose of this study was to compare complications after halfway and conventional RA.

Methods

We included 307 consecutive lesions that were divided into a conventional RA group (n = 244) and halfway RA group (n = 63). In analysis 1, the incidence of complications was compared between the conventional RA and halfway RA groups. Propensity-score matching was used to match the intentional halfway RA and conventional RA. In analysis 2, the incidence of complications was compared between the matched conventional RA and intentional halfway RA groups.

Results

Burr entrapment (0.4%) and major perforation (0.8%) were observed in the conventional RA group, whereas there was no burr entrapment or perforation in the halfway RA group. The success rate of halfway RA was 90.5%, which required switching from halfway RA to conventional RA. The incidences of slow flow and periprocedural myocardial infarction with slow flow were similar between the intentional halfway RA and matched conventional RA groups.

Conclusions

There was no burr entrapment or vessel perforation following halfway RA. The incidences of slow flow and periprocedural myocardial infarction were similar between the intentional halfway RA and the matched conventional RA, indicating the safety of halfway RA.

Treatment of In-Stent Restenosis by Excimer Laser Coronary Atherectomy and Drug-Coated Balloon: Serial Assessment with Optical Coherence Tomography

Objectives

We aimed to compare the results of neointimal modification before drug-coated balloon (DCB) treatment with excimer laser coronary atherectomy (ELCA) plus scoring balloon predilation versus scoring balloon alone in patients presenting with in-stent restenosis (ISR).

Background

Treatment of ISR with ELCA typically results in superior acute gain by neointima debulking. However, the efficacy of combination therapy of ELCA and DCB remains unknown.

Methods

A total of 42 patients (44 ISR lesions) undergoing DCB treatment with ELCA plus scoring balloon (ELCA group, n = 18) or scoring balloon alone (non-ELCA group, n = 24) were evaluated via serial assessment by optical coherence tomography (OCT) performed before, after intervention, and at 6 months.

Results

Although there was significantly greater frequency of diffuse restenosis and percent diameter stenosis (%DS) after intervention in the ELCA group, comparable result was shown in %DS, late lumen loss, and binary angiographic restenosis at follow-up. On OCT analysis, a decreased tendency in the minimum lumen area and a significant decrease in the minimum stent area were observed in the ELCA group between 6-month follow-up and after intervention (-0.89 ± 1.36 mm² vs. -0.09 ± 1.25 mm², p = 0.05, -0.49 ± 1.48 mm² vs. 0.28 ± 0.78 mm², p = 0.03, respectively). The changes in the neointimal area were similar between the groups, and target lesion revascularization showed comparable rates at 1 year (11.1% vs. 11.4%, p = 0.85).

Conclusions

Despite greater %DS after intervention, ELCA before DCB had possible benefit for late angiographic and clinical outcome.

Contemporary Management of Stent Failure: Part One

The occurrence of in-stent restenosis (ISR) still remains a daunting challenge in the current era, despite advancements in coronary intervention technology. The authors explore the underlying pathophysiology and mechanisms behind ISR, and describe how the use of different diagnostic tools helps to best elucidate these. They propose a simplistic algorithm to manage ISR, including a focus on how treatment strategies should be selected and a description of the contemporary technologies available. This article aims to provide a comprehensive outline of ISR that can be translated into evidence-based routine clinical practice, with the aim of providing the best outcomes for patients.

Challenges With Severe Coronary Artery Calcification in Percutaneous Coronary Intervention: A Narrative Review of Therapeutic Options

Coronary calcification often complicates atherosclerosis. With an aging population, coinciding with lower thresholds for coronary angiography and percutaneous coronary intervention (PCI), severe calcific coronary stenoses remain a challenge for interventional cardiologists. Although advances in coronary guidewires, percutaneous balloons, and adjunctive procedural devices have improved success of PCI, recalcitrant calcified lesions not amenable to the conventional technique frequently occur. Coronary atherectomy with plaque modification provides a therapeutic alternative. As such, various modalities such as rotational, orbital or laser atherectomy, and more recently shockwave lithoplasty have become therapeutic options for PCI. We provide a summary of the principles, technique, and contemporary evidence for these currently approved devices designed to treat severe coronary calcific lesions.

Linear Micro-patterned Drug Eluting Balloon (LMDEB) for Enhanced Endovascular Drug Delivery

In-stent restenosis (ISR) often occurs after applying drug eluting stents to the blood vessels suffering from atherosclerosis or thrombosis. For treatment of ISR, drug eluting balloons (DEB) have been developed to deliver anti-proliferative drugs to the lesions with ISR. However, there are still limitations of DEB such as low drug delivery efficiency and drug loss to blood flow. Although most researches have focused on alteration of drug formulation for more efficient drug delivery, there are few studies that have attempted to understand and utilize the contact modality of DEB drug delivery. Here, we developed a linear micro-patterned DEB (LMDEB) that applied higher contact pressure to enhance drug stamping to vascular tissue. Ex vivo and in vivo studies confirmed that higher contact pressure from micro-patterns increased the amount of drug delivered to the deeper regions of vessel. Finite element method simulation also showed significant increase of contact pressure between endothelium and micro-patterns. Quantitative analysis by high performance liquid chromatography indicated that LMDEBs delivered 2.3 times higher amount of drug to vascular tissue in vivo than conventional DEBs. Finally, efficacy studies using both atherosclerotic and ISR models demonstrated superior patency of diseased vessels treated with LMDEB compared to those treated with DEB.

Therapeutic Options for In-Stent Restenosis

PURPOSE OF REVIEW

In-stent restenosis (ISR) is a complex disease process that became apparent shortly after the introduction of stents into clinical practice. This review seeks to define in-stent restenosis (ISR) as well as to summarize the major treatment options that have been developed and studied over the past two decades.

RECENT FINDINGS

Recent developments in drug-coated balloons and bioresorbable vascular scaffolds have added new potential treatments for ISR. Two recent network meta-analyses performed a head-to-head comparison of all the various treatment modalities in order to identify the best approach to management of ISR. Current data suggests that repeat stenting with second-generation drug-eluting stents is most likely to lead to the best angiographic and clinical outcomes. In situations where repeat stenting is not preferable, drug-coated balloon therapy seems to be a reasonably effective alternative.

Computational Fluid Dynamics Modeling of the Burr Orbital Motion in Rotational Atherectomy with Particle Image Velocimetry Validation

Rotational atherectomy (RA) uses a high-speed rotating burr introduced via a catheter through the artery to remove hardened atherosclerotic plaque. Current clinical RA technique lacks consensus on burr size and rotational speed. The rotating burr orbits inside the artery due to the fluid force of the blood. Different from a common RA technique of upsizing burrs for larger luminal gain, a small burr can orbit to treat a large lumen. A 3D computational fluid dynamics (CFD) model was developed to simulate the burr motion and study the fluid flow and force in RA. A particle image velocimetry experiment was conducted to measure and validate the flow field including the radial and axial velocities and a pair of counter-rotating vortices near the burr equator in CFD. The hydraulic force on the burr and the contact force between the burr and the arterial wall were estimated by CFD. The contact force can be reduced by using smaller burr and lower rotational speed. Utilizing the small burr orbital motion has the potential to be an improved RA technique.

Current Management of In-Stent Restenosis

Despite the advent of the drug-eluting stents (DES) and improved stent design, in-stent restenosis (ISR) remains a challenging problem. The currently available options for treatment of ISR include angioplasty alone, repeat stenting with DES or drug-coated balloons. Several recent studies have compared the available options for treating ISR in an attempt to identify the preferred therapeutic strategy. In this review, we will discuss the currently available therapeutic strategies for the management of patients with ISR and the evidence supporting their use.

Restenosis of the Coronary Arteries: Past, Present, Future Directions

Restenosis is a pathologic response to vascular injury, characterized by neointimal hyperplasia and progressive narrowing of a stented vessel segment. Although advances in stent design have led to a dramatic reduction in the incidence of restenosis, it continues to represent the most common cause of target lesion failure following percutaneous coronary intervention. Efforts to maximize restenosis prevention, through careful consideration of modifiable risk factors and an individualized approach, are critical, as restenosis, once established, can be particularly difficult to treat. Novel approaches are on the horizon that have the potential to alter the natural history of this stubborn disease.