Contribution of stent underexpansion to recurrence after sirolimus-eluting stent implantation for in-stent restenosis

A case report of high cervical spinal infarction after stenting with severe stenosis at the beginning of left vertebral artery

BACKGROUND

Spinal cord infarction is an uncommon nervous system disorder. We present a case of high cervical cord infarction caused by stenting of the origin of the left vertebral artery (VA). The incidence of spinal cord infarction is minimal, and it must be distinguished from a number of other disorders. The diagnosis is primarily based on imaging, clinical symptoms, and history. Currently, there is no focused treatment for spinal cord infarction. Thrombolysis, high-dose glucocorticoid shocks, tube dilatation to promote circulation, and nutritional neurotropic medicines given early in the course of the disease can all help to slow the disease's progression. There is no agreement on the etiology, diagnosis, or therapy options for these people.

CASE PRESENTATION

On October 7, 2023, an 81-year-old man was admitted to the hospital primarily for recurrent chest tightness and pain that had persisted for more than 2 years and 1 month. Cerebral angiography upon admission revealed significant blockage of the right VA and stenosis of the left vertebral arterial origin. Six days following admission, a drug-eluting stenting procedure was carried out under local anesthesia to open the left VA origin via the femoral artery. Following the procedure, the patient experienced a progressive loss of muscle strength in all 4 limbs and paraplegia below the cervical 3 spinal cord. One week following the procedure, the patient was released from the hospital. After the procedure, the patient was released 1 week later. After the procedure, the patient's symptoms persisted for a month.

CONCLUSION

High awareness for high cervical cord infarction is required when neck discomfort and limb weakness with progressive progression arises after surgery. Complications of high cervical cord infarction following stenting for stenosis of VA origin are uncommon in clinical settings. Patients' prognoses can be improved by prompt diagnosis and care.

The Usefulness of Intravascular Ultrasound and Optical Coherence Tomography in Patients Treated with Rotational Atherectomy: An Analysis Based on a Large National Registry

BACKGROUND

Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have been shown to improve the clinical outcomes of percutaneous coronary interventions (PCIs) in selected subsets of patients.

AIM

The aim was to investigate whether the use of OCT or IVUS during a PCI with rotational atherectomy (RA-PCI) will increase the odds for successful revascularization, defined as thrombolysis in myocardial infarction (TIMI) 3 flow.

METHODS

Data were obtained from the national registry of PCIs (ORPKI) maintained by the Association of Cardiovascular Interventions (AISN) of the Polish Cardiac Society. The dataset includes PCIs spanning from January 2014 to December 2021.

RESULTS

A total of 6522 RA-PCIs were analyzed, out of which 708 (10.9%) were guided by IVUS and 86 (1.3%) by OCT. The postprocedural TIMI 3 flow was achieved significantly more often in RA-PCIs guided by intravascular imaging (98.7% vs. 96.6%, p < 0.0001). Multivariable analysis revealed that using IVUS and OCT was independently associated with an increased chance of achieving postprocedural TIMI 3 flow by 67% (odds ratio (OR), 1.67; 95% confidence interval (CI): 1.40-1.99; p < 0.0001) and 66% (OR, 1.66; 95% CI: 1.09-2.54; p = 0.02), respectively. Other factors associated with successful revascularization were as follows: previous PCI (OR, 1.72; p < 0.0001) and coronary artery bypass grafting (OR, 1.09; p = 0.002), hypertension (OR, 1.14; p < 0.0001), fractional flow reserve assessment during angiogram (OR, 1.47; p < 0.0001), bifurcation PCI (OR, 3.06; p < 0.0001), and stent implantation (OR, 19.6, p < 0.0001).

CONCLUSIONS

PCIs with rotational atherectomy guided by intravascular imaging modalities (IVUS or OCT) are associated with a higher procedural success rate compared to angio-guided procedures.

Intravascular Imaging in the Diagnosis and Management of Patients With Suspected Intracoronary Pathologies: A CJC White Paper

Intravascular imaging has become an integral part of the diagnostic and management strategies for intracoronary pathologies. In this White Paper we summarize current evidence and its implications on the use of intravascular imaging in interventional cardiology practice. The areas addressed are planning and optimization of percutaneous coronary intervention, management of stent failure, and evaluation of ambiguous coronary lesions and myocardial infarction with nonobstructive coronary disease. The findings presented followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system in an expert consensus process that involved a diverse writing group vetted by a review group. Expert consensus was achieved around 9 statements. Use of intravascular imaging in guiding percutaneous revascularization is supported by high-quality evidence, particularly for lesions with increased risk of recurrent events or stent failure. Specific considerations for intravascular imaging guidance of intervention in left main lesions, chronic occlusion lesions, and in patients at high risk of contrast nephropathy are explored. Use of intravascular imaging to identify pathologies associated with stent failure and guide repeat intervention, resolve ambiguities in lesion assessment, and establish diagnoses in patients who present with myocardial infarction with nonobstructive coronary disease is supported by moderate- to low-quality evidence. Each topic is accompanied by clinical pointers to aid the practicing interventional cardiologist in implementation of the White Paper findings. The findings presented in this White Paper will help to guide the use of intravascular imaging toward situations in which the balance of efficacy, safety, and cost are most optimal.

TRIM27 Promotes Endothelial Progenitor Cell Apoptosis in Patients with In-Stent Restenosis by Ubiquitinating TBK1

Approximately 2-10% in-stent restenosis (ISR) may occur following percutaneous coronary intervention (PCI) despite the use of modern drug-eluting stents (DES); thus, our study aimed to explore the effects of tripartite motif-containing (TRIM) 27 on ISR and the underlying mechanism. For this purpose, a total of 42 patients undergoing coronary angiography who had prior coronary angiography with DES implantation were recruited. Endothelial progenitor cells (EPCs) markers (defined as CD34 and vascular endothelial growth factoreceptor-2 (VEGFR-2)) in peripheral blood were measured to asses the circulating EPC level. The TRIM family-related gene expressions were detected by reverse transcription-quantitative polymerase chain reaction. Results suggested that ISR patients had reduced CD34+VEGFR-2+ and increased apoptosis rate of EPCs, along with upregulated TRIM27 and TRIM37 and downregulated TRIM28. TRIM27 promoted and TBK1 inhibited the apoptosis rate of EPCs. Mechanically, TRIM27 interacted with TBK1 to ubiquitinate TBK1 in in vitro study. In summary, TRIM27 promoted the progression of ISR in patients after PCI by ubiquitinating TBK1, which might provide novel ideas for the clinical treatment of ISR.

Off-Label Use of Peripheral Paclitaxel Drug-Coated Balloons in Management of Recurrent Coronary In-Stent Restenosis

Background

While not available for clinical use in the United States, dedicated drug-coated balloons (DCB) are currently under investigation for the management of coronary in-stent restenosis (ISR). Peripheral drug-coated balloons (P-DCB) have been used off-label for coronary ISR. Further data regarding this practice are needed. We aimed to describe outcomes in patients who underwent off-label P-DCB angioplasty for coronary ISR.

Methods

We analyzed data on P-DCB angioplasty for coronary ISR at a single high-volume center between April 1, 2015, and December 30, 2017. Demographic and procedural details were collected, with systematic follow-up as clinically indicated.

Results

Data from 31 patients treated with P-DCB angioplasty (mean age 68.0 ± 10.7 years) with coronary ISR (17 recurrent and 14 first time) were analyzed. Most patients presented with high-grade angina (81%) or myocardial infarction (13%). Treated ISR lesions were in native coronary arteries (68%), saphenous vein grafts (SVG, 23%), and the left internal mammary artery (10%). Diffuse intrastent ISR was common (69%) with a mean lesion length of 21.7 ± 12.4 mm. No postprocedural myocardial infarction occurred and 1 nonprocedural mortality occurred during index admission. At follow-up (median: 283, interquartile range [IQR]: 354 days), repeat angiography was performed in 19 patients (median: 212, IQR: 188 days), and 11 patients had target lesion recurrent ISR (Kaplan-Meier event-free survival estimate: 44.7%, 95% CI, 26.1%-76.5%).

Conclusions

In the absence of availability of dedicated coronary DCB, treatment of coronary ISR using P-DCB angioplasty was feasible, although follow-up demonstrated continued risk for recurrent ISR in this high-risk population.

Value of stent boost imaging in decision making after coronary stenting

BACKGROUND

Several studies reported the comparability of digital stent enhancement techniques (including stent boost imaging) in detecting suboptimal results of coronary stenting with Intra Vascular Ultrasound and optical coherence tomography.

AIMS

to assess results of stent deployment and determine the incidence of suboptimal results requiring changing final decision using stent boost imaging.

METHODS

This cross-sectional study included 120 patients eligible for PCI were recruited during a period of one year (January 2021 to 2022) using DES.

RESULTS

Suboptimal results were found in 38% of the PCI cases with stents (angiography guided). Importantly it was found that improper lesion preparation in our practice could not help improving stent optimization. Also, angiography guided PCI has significant incidence of suboptimal results. Digital stent enhancement techniques like stent boost have significant and important value in better decision making. After adjusting for age and sex, six factors were identified as independent predictors for final decision change (stent length, LAD/RCA affection, proximal segment affection, calcification, and optical coherence tomography.

CONCLUSION

This study has confirmed the utility of stent boost for the optimization of PCI in daily practice. Stent Boost is a simple and costless technique that provides an accurate assessment of a deployed stent without extending the procedure time and without more risk. It appears to be useful for the immediate evaluation of stent expansion and optimization of PCI by additional post-dilatation, when appropriate. Future studies are needed to determine whether Stent Boost data will correlate with adverse long-term clinical outcomes in patients undergoing PCI.

Clinical and procedural outcomes of percutaneous coronary intervention for de novo lesions involving the ostial left circumflex coronary artery

BACKGROUND

Percutaneous treatment for ostial left circumflex artery (LCx) lesions is known to be associated with suboptimal results.

AIMS

The present study aims to assess the procedural and long-term clinical outcomes of percutaneous coronary intervention (PCI) for de novo ostial LCx lesions overall and according to the coronary revascularization strategy.

METHODS

Consecutive patients undergoing PCI with second generation drug eluting stents or drug coated balloons for de novo ostial LCx lesions in three high-volume Italian centers between 2012 and 2021 were retrospectively evaluated. The primary endpoint was target-vessel revascularization (TVR) at 2 years. Secondary endpoints included major adverse cardiovascular and cerebrovascular events (MACCE), target lesion revascularization, myocardial infarction, stroke, all-cause death, and repeat revascularization.

RESULTS

A total of 366 patients were included in the analysis with a median follow-up of 901 (IQR: 450-1728) days. 79.5% of the patients were male, 33.6% were diabetic, 49.7% had a previous PCI, and 23.1% a prior surgical revascularization. Very ostial LCx stenting was performed in 34.1%, crossover from left main to LCx in 17.3%, and a two-stent strategy in 48.6% of cases, respectively. In the overall population, the incidence of TVR at 2 years was 19.0% while MACCE rate was 25.7%. No major differences in clinical outcomes were found according to the stenting strategy. Use of intracoronary imaging was associated with fewer MACCE (HR: 0.47, 95% CI: 0.25-1.13, p = 0.01), while the diameter of the stent implanted in the ostial LCx was associated with less TVR (HR: 0.43, 95% CI: 0.25-0.75, p = 0.002).

CONCLUSIONS

Percutaneous revascularization of the ostial LCx is associated with a high rate of TVR, regardless of the stenting strategy. Intracoronary imaging and proper stent sizing may reduce the failure rates.

Prognostic Impact of Atrial Fibrillation in Patients with Heavily Calcified Coronary Artery Disease Receiving Rotational Atherectomy

Background and Objectives: Although both rotational atherectomy (RA) and atrial fibrillation (AF) have a high thrombotic risk, there have been no previous studies on the prognostic impact of AF in patients who undergo percutaneous coronary intervention (PCI) using RA. Thus, the aim of the present study was to determine the prognostic impact of AF in patients undergoing PCI using RA. Materials and Methods: A total of 540 patients who received PCI using RA were enrolled between January 2010 and October 2019. Patients were divided into AF and sinus rhythm groups according to the presence of AF. The primary endpoint was net adverse clinical events (NACEs) defined as a composite outcome of all-cause death, myocardial infarction, target vessel revascularization, cerebrovascular accident, or total bleeding. Results: Although in-hospital adverse events showed no difference between those with AF and those without AF (in-hospital events, 54 (11.0%) vs. 6 (12.2%), p = 0.791), AF was strongly associated with an increased risk of NACE at 3 years (NACE: hazard ratio, 1.880; 95% confidence interval, 1.096-3.227; p = 0.022). Conclusions: AF in patients who underwent PCI using RA was strongly associated with poor clinical outcomes. Thus, more attention should be paid to thrombotic and bleeding risks.

State-of-art review: intravascular imaging in percutaneous coronary interventions

The history of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) reflects the relentless pursuit of innovation in interventional cardiology. These intravascular imaging technologies have played a pivotal role in our understanding of coronary atherosclerosis, vascular pathology, and the interaction of coronary stents with the vessel wall. Two decades of clinical investigations demonstrating the clinical efficacy and safety of intravascular imaging modalities have established these technologies as staples in the contemporary cardiac catheterization lab's toolbox and earning their place in revascularization clinical practice guidelines. In this comprehensive review, we will delve into the historical evolution, mechanisms, and technical aspects of IVUS and OCT. We will discuss the expanding evidence supporting their use in complex percutaneous coronary interventions, emphasizing their crucial roles in optimizing patient outcomes and ensuring procedural success. Furthermore, we will explore the substantial advances that have propelled these imaging modalities to the forefront of contemporary interventional cardiology. Finally, we will survey the latest developments in the field and explore the promising future directions that have the potential to further revolutionize coronary interventions.

In-vivo assessment of vascular injury for the prediction of in-stent restenosis

BACKGROUND

Despite optimizations of coronary stenting technology, a residual risk of in-stent restenosis (ISR) remains. Vessel wall injury has important impact on the development of ISR. While injury can be assessed in histology, there is no injury score available to be used in clinical practice.

METHODS

Seven rats underwent abdominal aorta stent implantation. At 4 weeks after implantation, animals were euthanized, and strut indentation, defined as the impression of the strut into the vessel wall, as well as neointimal growth were assessed. Established histological injury scores were assessed to confirm associations between indentation and vessel wall injury. In addition, stent strut indentation was assessed by optical coherence tomography (OCT) in an exemplary clinical case.

RESULTS

Stent strut indentation was associated with vessel wall injury in histology. Furthermore, indentation was positively correlated with neointimal thickness, both in the per-strut analysis (r = 0.5579) and in the per-section analysis (r = 0.8620; both p ≤ 0.001). In a clinical case, indentation quantification in OCT was feasible, enabling assessment of injury in vivo.

CONCLUSION

Assessing stent strut indentation enables periprocedural assessment of stent-induced damage in vivo and therefore allows for optimization of stent implantation. The assessment of stent strut indentation might become a valuable tool in clinical practice.

Safety and Efficacy of Post-Dilation in Percutaneous Coronary Intervention Using Polymer-Free Ultrathin Strut Sirolimus-Probucol Coated Drug-Eluting Stents

Background and Objectives: Polymer-free ultrathin strut sirolimus- and probucol-eluting stents (PF-SES) are recognized as safe and effective in diverse patient populations, although the implications of post-dilation during stent implantation remain underexamined. Materials and Methods: In this study, patients implanted with PF-SES at Gachon University Gil Medical Center between December 2014 and February 2018 were evaluated. Major adverse cardiovascular events (MACE), encompassing nonfatal myocardial infarction (MI), nonfatal stroke, and cardiovascular death were identified as primary outcomes, with secondary outcomes including target vessel revascularization (TVR), target lesion revascularization (TLR), and in-stent restenosis (ISR). Results: Of the 384 initial patients, 299 were considered eligible for analysis. The groups, delineated by those undergoing post-dilation (143 patients) and those not (156 patients), exhibited comparable rates of primary outcomes [hazard ratio (HR), 2.17; 95% confidence interval (CI), 0.40 to 11.87; p = 0.37]. The outcomes remained consistent irrespective of the post-dilation status and were similarly unaffected in multivariate analyses (HR, 2.90; 95% CI, 0.52 to 16.34; p = 0.227). Conclusions: These results suggest that the clinical outcomes of patients with post-dilation were similar to that of those without post-dilation in those with the polymer-free sirolimus- and probucol-eluting stents.

Pathogenesis, Evaluation, and Management of Pulmonary Vein Stenosis: JACC Review Topic of the Week

Pulmonary vein stenosis (PVS) can arise from several etiologies, including congenital, acquired, and iatrogenic sources. PVS presents insidiously, leading to significant delays in diagnosis. A high index of suspicion and dedicated noninvasive evaluation are key to diagnosis. Once diagnosed, both noninvasive and invasive evaluation may afford further insights into the relative contribution of PVS to symptoms. Treatment of underlying reversible pathologies coupled with transcatheter balloon angioplasty and stenting for persistent severe stenoses are established approaches. Ongoing refinements in diagnostic modalities, interventional approaches, postintervention monitoring, and medical therapies hold promise to further improve patient outcomes.

Drug-coated balloon therapy is more effective in treating late drug-eluting stent in-stent restenosis than the early occurring one-a systematic review and meta-analysis

Drug-eluting stent in-stent restenosis (DES-ISR) remains one of the important assignments to be resolved in interventional cardiology, as it is present in 5%-10% of total percutaneous coronary intervention cases. Drug-coated balloon (DCB) utilization is promising, as it comes with long-term protection from recurrent restenosis in optimal conditions without the hazard of higher risk for stent thrombosis and in-stent restenosis. We aim to reduce the need for recurrent revascularization in DES-ISR, specifying the population in which the DCB therapy should be used. In this meta-analysis, the results of studies containing data on the time frame between drug-eluting stent implantation and the clinical presentation of in-stent restenosis and concomitant drug-coated balloon treatment were summarized. A systematic search was performed in Medline, Central, Web of Science, Scopus and Embase databases on November 11th, 2021. The QUIPS tool was used to assess the risk of bias in the included studies. The occurrence of a major cardiac adverse events (MACE) composite endpoint, containing target lesion revascularization (TLR), myocardial infarction, and cardiac death, and each of these separately, was assessed at 12 months after the balloon treatment. Random effects meta-analysis models were used for statistical analysis. Data of 882 patients from four studies were analyzed. Across the included studies, a 1.68 OR (CI 1.57-1.80, p < 0.01) for MACE and a 1.69 OR (CI 1.18-2.42 p < 0.01) for TLR were observed, both in favor of late DES-ISR. The main limitation of the study is the relatively low patient number. Nevertheless, this analysis shows the first statistically significant results for the effect of DCB treatment in the early or late presentation of DES-ISR. As to date, intravascular imaging (IVI) remains limitedly accessible, other landmarks as the time frame of in-stent restenosis development are to be pursued to advance therapeutic outcomes. In consideration of other biological, technical and mechanical factors, time frame of occurrence as a prognostic factor could reduce the burden of recurrent revascularization in patients at an already high risk. Systematic Review Registration: identifier [CRD42021286262].

Sirolimus-Coated Balloon With a Microsphere-Based Technology for the Treatment of De Novo or Restenotic Coronary Lesions

BACKGROUND

Non stent-based local drug delivery with drug-coated balloon (DCB) is an alternative to drug-eluting stent with favorable clinical applicability in the treatment of selected coronary lesions. Our purpose was to report the initial performance, safety and efficacy evaluations of a novel sirolimus-coated balloon in the treatment of coronary lesions.

METHODS

This was a phase I (first-in-man), prospective, multicenter, single-arm trial evaluating the novel SELUTION SLR™ DCB (M.A. Med Alliance SA, Nyon, Switzerland), which incorporates a polymeric microsphere-based technology for controlled and continuous release of sirolimus, in the treatment of de novo or restenotic lesions.

RESULTS

A total of 56 patients/lesions were enrolled between November/2018 and March/2019. Diabetes was found in 46.6 %, and de novo lesions represented 79.6 % of cases. Device and procedural/clinical success were 100 % and 96.4 %, respectively. There was only one major adverse cardiac event (target lesion revascularization) reported at late follow-up. By quantitative coronary angiography analysis, mean % diameter stenosis was 30.5 ± 16.7 %, late lumen loss was 0.26 ± 0.45 mm and angiographic binary restenosis occurred in 4 of 45 cases at 6-month angiographic follow-up.

CONCLUSION

The novel SELUTION sirolimus-coated balloon demonstrated safety and efficacy in the treatment of diseased coronary vessels, including absence of mortality and relatively low late lumen loss at late follow-up.

Network Meta-analysis of Trials Comparing Intravascular Ultrasound, Optical Coherence Tomography, and Angiography-Guided Technique for Drug-Eluting Stent Implantation

Background

The current advances in coronary imaging with the introduction of intravascular ultrasound (IVUS), and more recently, optical coherence tomography (OCT) have overcome the limitations of coronary angiography.

Objective

This study aimed to conduct a comprehensive network meta-analysis of randomized clinical trials to report clinical outcomes among patients undergoing drug-eluting stent (DES) implantation either by IVUS- or OCT-guided technique or angiography alone.

Methods

PubMed/MEDLINE and EMBASE databases were searched systematically for all relevant published randomized clinical trials from the inception of the respective database to October 15th, 2021. The outcomes of interest assessed in this meta-analysis were major adverse cardiac events, myocardial infarction, target vessel revascularization, all-cause mortality, and cardiovascular mortality. All the endpoints were expressed as odds ratio (OR) with 95% CI. The network diagrams were computed using the OR as an effective measure. All statistical analyses were carried out in R statistical software version 4.0.3.

Results

A total of 14 randomized clinical trials were included in our meta-analysis. In patient undergoing DES implantation, angiography alone was associated with higher odds of major adverse cardiac events (OR, 1.62; 95% CI, 1.17-2.24), target vessel revascularization (OR, 1.60; 95% CI, 1.21-2.13) and cardiovascular mortality (OR, 1.97; 95% CI, 1.25-3.11). However, OCT demonstrated similar odds of major adverse cardiac events, cardiovascular mortality, and target vessel revascularization compared with IVUS. The odds of myocardial infarction and all-cause mortality were similar among all the 3 groups.

Conclusions

Although angiography alone was associated with worse outcomes than IVUS in a patient undergoing DES implantation, no difference in outcome was noted between patients undergoing DES implantation with OCT compared with IVUS. Advanced intracoronary imaging use should be encouraged to prevent excess mortality and morbidity.

Improving efficiency and operator proficiency during percutaneous coronary interventions utilizing a standardized optical coherence tomography workflow

OBJECTIVES

This study was designed to compare efficiency and quality metrics between percutaneous coronary intervention (PCI) procedures using optical coherence tomography (OCT) guided by a variable workflow versus a standardized workflow in a real-world population.

BACKGROUND

The LightLab (LL) Initiative was designed to evaluate the impact of a standardized OCT workflow during PCI to address barriers to adoption.

METHODS

The LL Initiative was a multicenter, prospective, observational study. PCI efficiency data were collected from 1/21/19 to 1/8/21 from 45 physicians at 17 US centers. OCT-guided PCIs were compared between baseline phase (variable workflow; N = 383) and the LL workflow utilization phase (N = 447). The LL workflow uses OCT to assess lesion Morphology, Length and Diameter, and then optimize outcomes by correcting for Medial dissection, stent mal-Apposition, and under-eXpansion (MLD MAX). Matching based on propensity scores was used to control for differences between PCIs.

RESULTS

After propensity matching, 291 paired procedures were included. Integration of the LL versus variable workflow resulted in no difference in procedure time (51 min vs. 51 min, p = 0.93). There was a reduction in radiation exposure (1124 mGy vs. 1493 mGy, p < 0.0001) and contrast volume (160 cc vs. 172 cc, p < 0.001). The LL workflow decreased the proportion of underexpanded lesions (34% vs. 54%, p < 0.0001) and improved minimum stent expansion (85% vs. 79%, p < 0.0001). Number of noncompliant balloons used was reduced with the LL workflow. (2.0 vs. 1.7, p < 0.01).

CONCLUSIONS

These data suggest that standardizing imaging with the LL workflow may overcome barriers to imaging and improve PCI outcomes without prolonging procedures.

Experience with Optical Coherence Tomography Enhanced by a Novel Software (Ultreon™ 1.0 Software)-The First One Hundred Cases

Introduction: Optical coherence tomography (OCT) intravascular imaging including the latest version Ultreon™ 1.0 Software (Abbott Vascular, Santa Clara, CA, USA), not only improve patients prognosis, but also facilitates improved percutaneous coronary intervention (PCI). Objectives: The aim of the study was to compare procedure related decision making, procedural indices, clinical outcomes according to the extent of stent expansion and assess risk factors of underexpansion in patients treated with PCI using OCT. Methods: The study comprised 100 patients, which were divided in groups according to the extent of stent expansion: <90 (29 patients) and ≥90% (71 patients). Comparison of OCT parameters, selected clinical and procedural characteristics was performed between groups. We assessed clinical outcomes during the follow-up: major adverse cardiovascular events and risk factors of stent underexpansion. Results: Patients from the stent underexpansion group were treated more often in the past with percutaneous peripheral interventions (p=0.02), no other significant differences being noted in general characteristics, procedural characteristics or clinical outcomes comparing both groups. Significant predictors of stent underexpansion assessed by simple linear univariable analysis included: hypercholesterolemia, obstructive bronchial diseases and treatment with inhalators, family history of cardiovascular disease, PCI of other than the left main coronary artery, stent and drug-eluting stent implantation, PCI without drug-eluting balloon, paclitaxel antimitotic agent, greater maximal stent diameter and lower mean Euroscore II value. Univariable logistic regression analysis revealed a correlation between stent underexpansion and greater creatinine serum concentration before [OR: 0.97, 95%CI: 0.95-0.99, p=0.01] and after PCI [OR: 0.98, 95%CI: 0.96-0.99, p=0.02]. Conclusions: Based on the presented analysis, the degree of stent expansion is not related to the selected procedural, OCT imaging indices and clinical outcomes. Logistic regression analysis confirmed such a relationship for creatinine level.

Incidence and Predictors of Outcome in the Treatment of In-Stent Restenosis with Drug-Eluting Balloons, a Real-Life Single-Centre Study

Objectives

To determine the one-year and five-year occurrence and prognosticators of major adverse cardiac events (MACE: composition of all-cause death, myocardial infarction, target vessel revascularization, and vessel thrombosis), mortality, and target lesion revascularization (TLR) in patients with in-stent restenosis (ISR) treated with drug-eluting balloons (DEBs).

Background

DEBs have become an emerging therapeutic option for ISR. We report the results of a single-center retrospective study on the treatment of ISR with DEB.

Methods

94 consecutive patients with ISR treated with the paclitaxel-eluting balloon were retrospectively studied between August 2011 and December 2019.

Results

The one-year MACE rate was 11.8%, and the five-year MACE rate was 39.8%. The one-year mortality was 5.3%, and the five-year mortality rate was 21.5%. The one-year TLR rate was 4.3%, and the five-year rate was 18.7%. The univariable-Cox proportional hazard models for TLR showed lesion length, and the number of DEBs per vessel is associated with adverse outcomes with H.R. of 1.038 (1.007–1.069) and 4.7 (1.6–13.8), respectively.

Conclusion

Our data indicate that at one year, DEBs provide an effective alternative to stenting for in-stent restenosis. Our five-year data, representing one of the longest-term follow-ups of DEB use, demonstrate high rates of MACE. The high five-year MACE reflects all-cause mortality in a high-risk population. This is offset by a reasonable five-year rate of TLR, indicating that DEB provides both short-term and long-term benefits in ISR.

Intravascular imaging in coronary stent restenosis: Prevention, characterization, and management

Despite the introduction of drug-eluting stents to combat the neointimal hyperplasia that occurred after BMS implantation, in-stent restenosis is still encountered in a significant number of patients, particularly as increasingly complex lesions are tackled by percutaneous coronary intervention. Many biological and mechanical factors interplay to produce restenosis, some of which are avoidable. Intravascular imaging provided unique insights into various forms of stent-related mechanical issues that contribute to this phenomenon. From a practical perspective, intravascular imaging can therefore help to optimize the stenting procedure to avert these issues. Moreover, once the problem of restenosis eventuates, imaging can guide the management by tackling the underlying identified mechanism. Finally, it can be used to evaluate the re-intervention results. Nevertheless, with the emergence of different treatment options, more evidence is needed to define patient/lesion-specific characteristics that may help to tailor treatment selection in a way that improves clinical outcomes.

Procedure-Related Differences and Clinical Outcomes in Patients Treated with Percutaneous Coronary Intervention Assisted by Optical Coherence Tomography between New and Earlier Generation Software (Ultreon™ 1.0 Software vs. AptiVue™ Software)

(1) Introduction: Optical coherence tomography (OCT) intravascular imaging facilitates percutaneous coronary intervention (PCI). Software for OCT is being constantly improved, including the latest version Ultreon™ 1.0 Software (U) (Abbott Vascular, Santa Clara, CA, USA). In the current analysis, we aim to compare processing results, procedural indices as well as clinical outcomes in patients treated via PCI. This was conducted using earlier generation OCT imaging software versions (non-U) and the newest available one on the market (U). (2) Methods: The study comprised 95 subsequent and not selected patients (55 processed with U and 40 non-U). The non-U processings were transferred for evaluation by U software, while the comparison of OCT parameters, selected clinical and procedural indices was performed between groups. We further assessed clinical outcomes during the follow-up period, i.e., major adverse cardiovascular events (MACE) and predictors of stent expansion. (3) Results: We did not detect any differences in general features between either of the assessed groups at baseline. Non-U software was more often used for bare-metal stenting (p = 0.004), while PCIs in the U group demanded a greater number of stents (p = 0.03). The distal reference of external elastic lamina (EEL) diameter was greater in the non-U group (p = 0.02) with no concurrent differences in minimal (p = 0.27) and maximal (p = 0.31) stent diameter. It was also observed that MACE was more frequently observed in the non-U group (p = 0.01). Neither univariable (estimate: 0.407, 95%CI: (−3.182) − 3.998, p = 0.82) nor multivariable (estimate: 2.29, 95%CI: (−4.207) − 8.788, p = 0.5) analyses demonstrated a relationship between the type of software and stent expansion. (4) Conclusions: Improvement in the software for image acquisition and processing of OCT is not related to stent expansion. The EEL diameter is preferably used to select the distal stent diameter in newer software.

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.

Outcomes and prognostic factors of patients treated for in-stent restenosis: a retrospective single-center experience

BACKGROUND

The incidence of in-stent restenosis (ISR) remains relatively common despite the use of drug-eluting stents. Outcomes and prognostic factors following ISR revascularization are still being investigated. We aimed to describe the outcomes following different ISR treatment strategies in order to identify prognostic factors associated with worse outcomes.

RESULTS

In a retrospective cohort study, we included patients who were admitted to our department and treated for ISR, from January 2017 to December 2018. All patients were followed up for a median period of 24 months. Major cardiac adverse event (MACE) was a composite outcome of the following events: myocardial infarction, target vessel revascularization, target lesion revascularization or cardiovascular death. MACEs were collected during follow-up. Our population consisted of 116 patients. Mean age was 60 years old with a sex ratio of 2.8. During follow-up, 44 patients (37.9%) had at least one MACE. Independent factors identified by multivariate logistic regression were ISR of the proximal left anterior descending artery [Odds ratio (OR) = 1.29; 95% confidence interval (95% CI) 1.16-1.81; p = 0.05], diffuse ISR [OR = 2.16; 95% CI 1.1-3.47; p = 0.022], double or triple vessel disease [OR = 2.97; 95% CI 1.2-6.8; p = 0.008], two or more stents per lesion [OR = 1.82; 95% CI 1.14-2.21, p = 0.031] and absence of post-dilatation in the initial angioplasty [OR = 1.32; 95% CI 1-1.35; p = 0.04].

CONCLUSIONS

Our study suggested that ISR is related to poor outcomes. Identifying prognostic factors would play a key role in the refinement of interventional techniques.

Novel predictors of stent under-expansion regarding calcified coronary lesions assessed by optical coherence tomography

A previous calcium scoring system using circumferential angle, thickness, and length of coronary calcium by OCT could assist in predicting stent under-expansion. However, this scoring system only reflects the calcification distribution within a single cross-section and fails to consider the lumen's original size. The current study aims to investigate whether novel parameters to quantify calcium lesions, including calcium burden, area, and volume assessed by optical coherence tomography (OCT), could predict stent under-expansion related to calcium lesions. Consecutive patients admitted between March 10th to October 19th 2021 with calcified coronary lesions undergoing percutaneous coronary intervention (PCI) with OCT guidance were screened for inclusion. The calcium burden, area, and volume of the target lesions were measured using OCT at pre-PCI. After successful stent implantation, stent expansion at the corresponding lesions was also measured by OCT. A total of 125 patients who underwent OCT-guided PCI were included in this study. While the calcium grades by angiography failed to show a significant correlation with stent expansion, maximum and average calcium burden, maximum calcium area, and calcium volume exhibited a moderate correlation with stent expansion. According to the receiver operating characteristic curves, the optimal cutoffs of calcium volume and area for predicting stent under-expansion were 4.37 mm³ and 2.48 mm² , respectively. Calcium burden, area, and volume by OCT are more favorable predictors of stent under-expansion given its better performance than calcium grades by angiography. Using cutoffs of calcium area and volume could identify high-risk patients of under-expansion and might guide future clinical practice.

Intravascular Lithotripsy in Calcified Coronary Lesions: A Single-Center Experience in “Real-World” Patients

Objectives

This study aims to describe the outcome of intravascular lithotripsy (IVL) when used with different indications and to assess the short- and long-term outcomes of IVL-facilitated percutaneous coronary intervention (PCI).

Background

Intravascular lithotripsy can improve the results of PCI of calcified coronary lesions with a low rate of periprocedural complications.

Methods

A total of 105 consecutive patients with 110 calcified lesions underwent IVL. A total of 87 de novo lesions were treated by IVL with the following indications: 25 before attempting other balloon-based devices (primary IVL), 51 after the failure of non-compliant balloon dilatation (secondary IVL), and 11 after stent implantation because of stent under expansion (bailout IVL). In 23 lesions, IVL was used for the treatment of in-stent restenosis (ISR). Effectiveness (angiographic success) and safety [major adverse cardiovascular events (MACEs) and IVL-related procedural complications] endpoints were assessed.

Results

Angiographic success was achieved in 84.6% of lesions. Early MACEs were periprocedural MI only, ranging from 6.7 to 20% depending on MI definition. The flow-limiting dissections rate was 2.7%. A total of five (4.5%) IVL balloons ruptured during treatment with subsequent vessel perforation in 1 case. MACEs at 12 months were 13.3%, with TLR occurring in 8 lesions (12% primary IVL, 0% secondary IVL, 0% bailout IVL, and 21.7% IVL for ISR, p = 0.002).

Conclusion

Treatment of calcified coronary lesions with IVL in a “real-world” setting can be performed with high success, low rate of procedural complications, and an acceptable MACEs rate. Target lesion failure may be more frequent when IVL is performed for the treatment of ISR due to calcium-mediated stent under expansion.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

Intravascular lithotripsy in calcified subclavian and innominate peripheral artery disease: A single centre experience

BACKGROUND

Intravascular lithotripsy (IVL) is a novel tool for the treatment of calcified vascular stenosis. Recently, IVL has been successfully used for modification of calcified plaque in coronary and lower extremity peripheral arteries with promising results. However, experience in subclavian and innominate peripheral arterial disease is limited. This study aims to report our initial experience of IVL use in calcified subclavian and innominate vasculature.

METHODS

This was a retrospective review of all the cases of IVL performed in subclavian and innominate arteries at the Miriam Hospital, Providence, between January 2019 and May 2020. Data on the baseline and procedural characteristics were collected. The primary endpoint was procedural success defined as residual stenosis of <20% after stenting. Other endpoints of interest were; 1) procedural complications, including dissections, perforations, abrupt closure, slow or no-reflow, thrombosis, and distal embolization; 2) in-hospital major adverse cardiac events (MACE) defined as a composite of death, myocardial infarction, or stroke/transient ischemic attack.

RESULTS

A total of 7 patients with 13 lesions undergoing IVL were included. Of these, 5 (71%) were women, the mean age was 74.6 ± 12.9, and the mean BMI was 25.1 ± 6.7. IVL was successfully delivered to all the target lesions with a mean 252.9 ± 54.4 pulses delivered per patient. Procedural success was achieved in 100% of the treated lesions. No procedure-related complications or in-hospital MACE occurred in any of the patients.

CONCLUSIONS

In this single-center retrospective analysis, IVL facilitated acute procedural success without any procedural complications in severely calcified stenoses of the subclavian and innominate vasculature. Larger studies with an active comparator and longer follow-up are needed to establish the relative efficacy and safety of IVL use in this vascular bed.

Stent visualization methods to guide percutaneous coronary interventions and assess long-term patency

Evaluation of acute percutaneous coronary intervention (PCI) results and long-term follow-up remains challenging with ongoing stent designs. Several imaging tools have been developed to assess native vessel atherosclerosis and stent expansion, improving overall PCI results and reducing adverse cardiac events. Quantitative coronary analysis has played a crucial role in quantifying the extent of coronary artery disease and stent results. Digital stent enhancement methods have been well validated and improved stent strut visualization. Intravascular imaging remains the gold standard in PCI guidance but adds costs and time to the procedure. With a recent shift towards non-invasive imaging assessment and coronary computed tomography angiography imaging have shown promising results. We hereby review novel stent visualization techniques used to guide PCI and assess stent patency in the modern PCI era.

One-Year Outcomes After Treatment of Ostial In-Stent Restenosis in Left Circumflex Versus Left Anterior Descending or Right Coronary Artery

The prognosis of left circumflex (LC) versus non-LC in-stent restenosis (ISR) ostial lesions following treatment has not been assessed. We aimed to assess this prognosis. Anecdotally, treatment of ostial LC ISR has been associated with high recurrence rates. We performed a retrospective analysis of patients from our institution who underwent coronary intervention of an ostial ISR lesion between 2003 and 2018. The primary endpoint was target lesion revascularization (TLR) and major adverse cardiovascular events (MACE). Overall, 563 patients underwent ostial ISR lesion intervention, 144 for an ostial LC ISR lesion. Compared to patients with ostial ISR in non-LC lesions, patients with ostial LC ISR were older, had higher rates of diabetes mellitus and previous coronary bypass surgery. At 1-year follow-up, TLR-MACE rates were 26.6% in the LC group versus 18.4% in the non-LC group (p = 0.036). The TLR rate was also higher in the LC group compared to the non-LC group (p = 0.0498). Univariate and multivariate analyses demonstrated a higher TLR-MACE rate for LC versus non-LC ostial ISR lesions. In conclusion, our study shows increased event rates after treatment of LC versus non-LC ISR lesions. Further studies should be done to assess the optimal treatment approach for ostial LC ISR.

Comparison of optical coherence tomography-guided and intravascular ultrasound-guided rotational atherectomy for calcified coronary lesions

Background

To compare the effect and outcomes of optical coherence tomography (OCT)-guided rotational atherectomy (RA) with intravascular ultrasound (IVUS)-guided RA in the treatment of calcified coronary lesions.

Methods

Data of calcified coronary lesions treated with RA that underwent OCT-guided or IVUS-guided from January 2016 to December 2019 at a single-center registry were retrospectively analyzed. The effect and outcomes between underwent OCT-guided RA and IVUS-guided RA were compared.

Results

A total of 33 lesions in 32 patients received OCT-guided RA and 51 lesions in 47 patients received IVUS-guided RA. There was no significant difference between OCT-guided RA group and IVUS-guided RA group in clinical baselines characteristics. Comparing the procedural and lesions characteristics of the two groups, the contrast volume was larger [(348.8 ± 110.6) ml vs. (275.2 ± 76.8) ml, P = 0.002] and the scoring balloon was more frequently performed (33.3% vs. 3.9%, P = 0.001) after RA and before stenting in the OCT-guided RA group. Comparing the intravascular imaging findings of the two groups, stent expansion was significantly larger in the OCT-guided RA group ([82 ± 8]% vs. [75 ± 9]%, P = 0.001). Both groups achieved procedural success immediately. There were no significantly differences in the incidence of complications. Although there was no statistical difference in the occurrence of MACE at 1 year between OCT-guided RA group and IVUS-guided RA group (3.1% vs. 6.4%, P = 0.517), no cardiovascular death, TVR and stent thrombosis occurred in OCT-guided RA group.

Conclusions

OCT-guided RA compared to IVUS-guided RA for treating calcified coronary lesions resulted in better stent expansion and may have improved prognosis.

Mechanical performances of balloon post-dilation for improving stent expansion in calcified coronary artery: Computational and experimental investigations

Stent deployment in a calcified coronary artery is often associated with suboptimal outcomes such as stent underexpansion and malapposition. Post-dilation after stent deployment is commonly used for optimal stent implantation. There is no guideline for choosing the post-dilation balloon diameter and inflation pressure. In this work, ex-vivo/in-silico experiments were performed to investigate the efficacy of post-dilation balloon diameter and inflation pressure in improving the stent expansion in a calcified lesion. Post-dilations with three balloon diameters (3 mm, 3.5 mm, and 4 mm) were performed. For each balloon diameter, three inflation pressures (10 atm, 20 atm, and 30 atm) were sequentially applied. In ex-vivo experiments, optical coherence tomography images were acquired during the stenting procedure, i.e., pre- and post-deployment of 3 mm diameter stent, as well as after each post-dilation. The results from in-silico experiments were compared with ex-vivo experiments in terms of lumen area. In addition, stretch ratio analysis was developed to predict the stent-induced lumen area, along with the strain analysis and the in-silico experiments. Results have shown that target lumen area could be achieved with an oversized nominal balloon diameter of +0.5 mm (i.e., 0.5 mm greater than reference lumen diameter) at an inflation pressure of 20 atm. After each post-dilation, fibrotic tissue demonstrated a larger strain, contributing to improved lumen gain. However, minimal changes were observed in calcification. Moreover, a strong correlation (R² = 0.95) between the stretch ratio of fibrotic tissue and lumen area after each post-dilation was observed. This indicated that the morphology of the fibrotic tissue could be a potential marker to predict the lumen gain. The detailed mechanistic quantifications of a single lesion cannot be generalized to all clinical cases. However, this work could be used to provide a fundamental understanding of the post-dilations, to develop experimental protocols for producing generalized guidelines, and to exploit their potential for optimal pre- and post-stent strategies.

Is coronary artery tortuosity a predisposing factor for drug-eluting stent restenosis?

BACKGROUND

Coronary artery tortuosity (CAT) is a relatively common finding on coronary angiography and may be associated with impaired left ventricular relaxation and coronary ischemia However, the significance of CAT remains unknown. This study aimed to investigate whether the severity of tortuosity in the targeted coronary segment is a predictor of stent restenosis.

METHODS

The study included a total of 637 patients undergoing drug-eluting stent implantation due to stable or unstable angina and who had no native coronary artery stenosis on their last coronary angiogram. The patients were separated into two groups: 312 patients with in-stent restenosis and 325 patients without in-stent restenosis. All patients underwent computed tomography (CT) coronary angiography after invasive angiography and CAT was calculated using the computer software.

RESULTS

Patients with in-stent restenosis had higher CAT than those without restenosis (1.25 ± 0.11 vs. 1.11 + 0.07, p < 0.001). Multivariate Cox regression analysis showed that the tortuosity index (hazard ratio [HR]: 1.246 95% confidence interval [CI]: 1.127-1.376 p < 0.001) and the circumflex lesion (HR: 1.437 95% CI: 1.062-1.942 p = 0.019) were independently associated with in-stent restenosis. With the threshold value of severe tortuosity set at 1.15, the prediction of could be made with 81% sensitivity and 80% specificity.

CONCLUSION

The severity of tortuosity is proportional to coronary in-stent stenosis in patients with stable and unstable angina pectoris undergoing drug-eluting stent implantation for a severe single coronary artery.

Association between coronary artery calcium score and stent expansion in percutaneous coronary intervention

BACKGROUND

Measurement of the coronary artery calcification score using multidetector computed tomography (MDCT) is a useful noninvasive test for the diagnosis of coronary artery disease. However, whether pre-intervention assessment of the target vessel coronary artery calcification (TV-CAC) score is associated with stent expansion failure and future target lesion revascularization (TLR), remains unknown. This study aimed to determine the association between the TV-CAC score measured by MDCT and stent expansion rate in patients who underwent IVUS-guided PCI for stable angina.

METHODS

We conducted a retrospective observational study including 135 consecutive patients (186 target lesions) who underwent MDCT and were scheduled for the first PCI. The patients were divided into 2 groups based on the median value of the TV-CAC score. The primary outcome was the stent expansion rate measured by IVUS after stent implantation. The secondary outcome was TLR within 1 year.

RESULTS

Stent expansion rate was associated with the TV-CAC score (p < 0.001). According to the ROC curve analysis, the TV-CAC score had the largest area under the curve (AUC) for the stent expansion area of 0.90 (AUC = 0.893, p < 0.001). The TV-CAC score was a positive predictor for stent expansion rate of <90% (odds ratio: 7.54, p < 0.001). Mediation analysis showed that stent under-expansion was a mediator of the association between high TV-CAC and TLR.

CONCLUSIONS

Our study demonstrates that pre-intervention assessment of TV-CAC using MDCT is a predictor of stent expansion. The TV-CAC score might predict the complexity and help in the PCI operative strategy.

The Clinical and Angiographic Outcomes of Postdilation after Percutaneous Coronary Intervention in Patients with Acute Coronary Syndrome: A Systematic Review and Meta-Analysis

OBJECTIVE

The effect of postdilation in patients with acute coronary syndrome is still controversial. This meta-analysis aims to analyze the clinical and angiographic outcomes of postdilation after percutaneous coronary intervention in patients with acute coronary syndrome.

METHODS

PubMed, Embase, the Cochrane Library, Web of Science, CNKI, and Wangfang databases were searched from inception to August 30, 2020. Eligible studies from acute coronary syndrome patients treated with postdilation were included. The primary clinical outcome was major adverse cardiovascular events (MACE), the secondary clinical outcomes comprised all-cause death, stent thrombosis, myocardial infarction, and target vessel revascularization, and the angiographic outcomes were no reflow and slow reflow.

RESULTS

11 studies met inclusion criteria. In clinical outcomes, our pooled analysis demonstrated that the postdilation had a tendency of decreasing MACE (OR = 0.67, 95% CI 0.45-1.00; P = 0.05) but significantly increased all-cause death (OR = 1.49, 95% CI 1.05-2.12; P = 0.03). No significant difference existed in stent thrombosis (OR = 0.71, 95% CI 0.40-1.26; P = 0.24), myocardial infarction (OR = 1.40, 95% CI 0.51-3.83; P = 0.51), and target vessel revascularization (OR = 0.61, 95% CI 0.21-1.80; P = 0.37) between postdilation and non-postdilation groups. In angiographic outcomes, there were no significant differences in no reflow (OR = 1.19, 95% CI 0.54-2.65; P = 0.66) and slow reflow (OR = 1.12, 95% CI 0.93-1.35; P = 0.24) between two groups.

CONCLUSIONS

The postdilation tends to reduce the risk of MACE but significantly increases all-cause death, without significantly affecting stent thrombosis, myocardial infarction, target vessel revascularization, and coronary TIMI flow grade. However, more randomized controlled trials are required for investigating the effect of postdilation for patients with acute coronary syndrome (registered by PROSPERO, CRD42020160748).

The Prognostic Value of a Validated and Automated Intravascular Ultrasound-Derived Calcium Score

Background

Coronary calcification has been linked to cardiovascular events. We developed and validated an algorithm to automatically quantify coronary calcifications on intravascular ultrasound (IVUS). We aimed to assess the prognostic value of an IVUS-calcium score (ICS) on patient-oriented composite endpoint (POCE).

Methods

We included patients that underwent coronary angiography plus pre-procedural IVUS imaging. The ICS was calculated per patient. The primary endpoint was a composite of all-cause mortality, stroke, myocardial infarction, and revascularization (POCE).

Results

In a cohort of 408 patients, median ICS was 85. Both an ICS ≥ 85 and a 100 unit increase in ICS increased the risk of POCE at 6-year follow-up (adjusted hazard ratio (aHR) 1.51, 95%CI 1.05–2.17, p value = 0.026, and aHR 1.21, 95%CI 1.04–1.41, p value = 0.014, respectively).

Conclusions

The ICS, calculated by a validated automated algorithm derived from routine IVUS pullbacks, was strongly associated with the long-term risk of POCE.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s12265-021-10103-1.

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.

Imaging-guided PCI for event suppression in Japanese acute coronary syndrome patients: community-based observational cohort registry

Although there is accumulating evidence for the usefulness of imaging-guided percutaneous coronary intervention (PCI), there are few studies for acute coronary syndrome (ACS), and the impact of the frequency of use has not been well addressed. From the Kumamoto Intervention Conference Study; a Japanese registry comprising 17 institutions, consecutive patients undergoing successful PCI from April 2008 through March 2014 were enrolled. Subjects were divided into two groups: imaging-guided PCI and angiography-guided PCI. Clinical outcome was a composite of cardiac death, non-fatal myocardial infarction, and stent thrombosis within 1 year. A total of 6025 ACS patients were enrolled: 3613 and 2412 patients with imaging- and angiography-guided PCI, respectively. Adverse cardiac events were significantly lower in the imaging-guided PCI group (long-rank P < 0.001). Even after propensity-score matching, the event rates still showed significant differences between the two groups (log-rank P = 0.004). To assess the effects of frequency of imaging usage, we divided the 17 institutions into six low-, six moderate-, and five high-frequency groups. The event rates decreased depending on the frequency, seemingly driven by stepwise event suppression in angiography-guided PCI. In Japanese ACS patients, the incidence of adverse clinical events in patients treated with imaging-guided PCI were significantly lower than that in patients with angiography-guided PCI. Better clinical result was found in the institutions using intravascular imaging more frequently. University Hospital Medical Information Network (UMIN)-CTR ( http://www.umin.ac.jp/ctr/ ). Identifier: KICS (UMIN000015397).

Mechanisms of drug-eluting stent restenosis

Drug-eluting stents (DES) were developed to overcome in-stent restenosis (ISR), which has long been considered the main complication limiting the long-term efficacy of coronary stenting. New-generation DES which composed of advanced stent design with and without specific biocompatible polymer contributes a reduction of the incidence of ISR to rate ranging from 5 to 10%. The precise reasons of DES restenosis are still controversial and not fully understood. Angiographic and coronary images at the index procedure, systemic status of patients, medications, and intracoronary imaging at ISR site are all considered to find the possible mechanisms of DES restenosis. Multiple biological, genetic, mechanical, and technical factors might intricately contribute to DES restenosis. Biological and genetic factors of ISR are not able to be sufficiently modified by the current medical approaches. Tailored treatments avoiding mechanical and technical factors of ISR are required to reduce DES restenosis. Elucidation of DES restenosis leads to further improvement in the current DES system and finds the optimal approach to treat DES restenosis. The possible mechanisms of DES restenosis are discussed in this review.

Simulation-Driven Machine Learning for Predicting Stent Expansion in Calcified Coronary Artery

In this work, we integrated finite element (FE) method and machine learning (ML) method to predict the stent expansion in a calcified coronary artery. The stenting procedure was captured in a patient-specific artery model, reconstructed based on optical coherence tomography images. Following FE simulation, eight geometrical features in each of 120 cross sections in the pre-stenting artery model, as well as the corresponding post-stenting lumen area, were extracted for training and testing the ML models. A linear regression model and a support vector regression (SVR) model with three different kernels (linear, polynomial, and radial basis function kernels) were adopted in this work. Two subgroups of the eight features, i.e., stretch features and calcification features, were further assessed for the prediction capacity. The influence of the neighboring cross sections on the prediction accuracy was also investigated by averaging each feature over eight neighboring cross sections. Results showed that the SVR models provided better predictions than the linear regression model in terms of bias. In addition, the inclusion of stretch features based on mechanistic understanding could provide a better prediction, compared with the calcification features only. However, there were no statistically significant differences between neighboring cross sections and individual ones in terms of the prediction bias and range of error. The simulation-driven machine learning framework in this work could enhance the mechanistic understanding of stenting in calcified coronary artery lesions, and also pave the way toward precise prediction of stent expansion.

Additional postdilatation using noncompliant balloons after everolimus-eluting stent implantation: Results of the PRESS trial

Background

There are limited data on the clinical value of routine postdilatation using noncompliant balloons after contemporary drug‐eluting stent implantation.

Hypothesis

Additional postdilatation using noncompliant balloons after everolimus‐eluting stent implantation could provide better clinical outcomes.

Methods

We randomly assigned 1774 patients with coronary artery disease to undergo additional high‐pressure postdilatation using noncompliant balloons and moderate‐pressure dilatation using stent balloons after everolimus‐eluting stent implantation. The primary endpoint was a composite of death, myocardial infarction (MI), stent thrombosis, and target vessel revascularization (TVR) 2 years after randomization.

Results

The study was discontinued early owing to slow enrollment. In total, 810 patients (406 patients in the high pressure group and 404 in the moderate pressure group) were finally enrolled. At 2 years, the primary endpoint occurred in 3.6% of patients in the high pressure group and in 4.4% of those in the moderate pressure group (P = .537). In addition, no significant differences were observed between the two groups in the occurrence of an individual end point of death (0.8% in the high pressure group vs 1.5% in the moderate group, P = .304), MI (0.2% vs 0.5%, P = .554), stent thrombosis (0% vs 0.2%, P = .316), or TVR (2.8% vs 2.6%, P = .880).

Conclusions

The strategy of routine postdilatation using noncompliant balloons after everolimus‐eluting stent implantation did not provide incremental clinical benefits.

Impact of the Balloon Inflation Time and Pattern on the Coronary Stent Expansion

Objectives

To assess the expansion pattern of coronary stents by using different balloon inflation times and pressures.

Background

The selection of coronary stent size and its proper deployment is crucial in coronary artery interventions, having an impact on the success of the procedure and further therapy.

Methods

Ten pairs of different stents were deployed under nominal pressure using sequential (5, 5, 10, and 10 seconds of repeated inflations, thus 30 seconds of summarized time) and continuous (30 seconds) deployment pattern. After each given time-point, intraluminal stent measurements were performed by optical coherence tomography (OCT) and intravascular ultrasound (IVUS).

Results

Both in-stent diameters and cross-section areas (CSA) of paired stents measured by OCT at all sequential time-points were significantly smaller compared to given manufacturers charts' values (90% to 94% for diameters and 81% to 88% for CSA, p<0.05). Significant increase of in-stent diameter and CSA was observed across the step-by-step deployment pattern. In-stent lumen measurements were significantly larger when sequential deployment pattern was applied compared to continuous deployment. Additional measurements were also done for overlapping segments of stents, showing smaller in-stent measurements of the latter compared to nonoverlapping segments. Validation of OCT and IVUS measurements using a phantom metallic tube showed perfect reproducibility with OCT and overestimation with IVUS (8% for diameters and 16% for CSA).

Conclusions

Stent diameter after deployment is time-dependent and not only pressure-dependent. Different stent expansion behavior, depending on the applied deployment pattern (sequential and nonsequential), was observed.