Delayed arterial healing and increased late stent thrombosis at culprit sites after drug-eluting stent placement for acute myocardial infarction patients: an autopsy study

Late stent strut apposition and coverage after drug-eluting stent implantation by optical coherence tomography in patients with acute myocardial infarction

BACKGROUND

Although drug-eluting stents (DES) are effective, stent thrombosis (ST) remains a major concern in patients with acute myocardial infarction (AMI) who undergo DES implantation. We aimed to evaluate the incidence of late stent malapposition (SM) and uncovered struts 12 months after implantation of a bioabsorbable polymer everolimus-eluting stent (BP-EES) or a durable polymer zotarolimus-eluting stent (DP-ZES) in patients with AMI using optical coherence tomography (OCT).

METHODS

Sixty-nine patients with AMI were randomly assigned 2:1 to the BP-EES (46 patients) or DP-ZES (23 patients) groups. The coprimary endpoints were the incidences of late SM and uncovered stent struts in OCT strut-level analysis at 12 months postimplantation.

RESULTS

The 51 patients who completed the 12-month follow-up OCT (BP-EES, 36 patients, 39 lesions; DP-ZES, 15 patients, 18 lesions) showed no intergroup differences in the incidence of acute SM (BP-EES vs. DP-ZES; 12.25 ± 14.27% vs. 12.35 ± 10.55%, P = 0.981) at the index procedure. The incidence of late SM (0.12 ± 0.42% vs. 0.14 ± 0.25%, P = 0.873) and uncovered struts (1.69 ± 3.44% vs. 2.45 ± 3.23%, P = 0.532) also did not differ between the two DES groups at 12-month postimplantation.

CONCLUSION

Twelve-month OCT measurements showed no significant differences in late SM and uncovered struts between the BP-EES and DP-ZES stents. Thus, contemporary second-generation DES show a very low rate of late SM and uncovered struts after 12 months in AMI, regardless of stent polymer type.

TRIAL REGISTRATION

Late stent strut apposition and coverage after drug-eluting stent implantation by OCT in patients with AMI (APPOSITION AMI-II) (NCT02770651).

Comparison of very early-phase vascular response to the CD34 antibody‑covered sirolimus‑eluting stent versus durable polymer-coated everolimus-eluting stent

The COMBO stent is a unique biodegradable polymer sirolimus-eluting stent with an anti-CD34 antibody coating that captures endothelial progenitor cells and potentially promotes vessel healing. There are limited data regarding strut tissue coverage at the very short-term period after COMBO stent implantation compared to other types of drug-eluting stents in the same patient. This prospective study enrolled patients who had COMBO Plus stent and durable polymer-coated everolimus-eluting stent (XIENCE stent) implanted simultaneously in the same vessel for long coronary lesions. Strut tissue coverage within 1 month after implantation was compared using optical coherence tomography. Struts fully covered with tissue were defined as covered, and healthy tissue coverage was defined as tissue thickness with ≥ 40 μm. A total of 21 patients, 11 (52%) of whom presented with acute coronary syndrome, were enrolled. A total of 4798 struts from 21 COMBO Plus stents and 4608 struts from 21 XIENCE stents were analyzed at an average of 19.8 ± 6.5 days after implantation. In the lesion-level analysis, covered struts were more frequently observed (83.7 ± 7.4% vs. 76.9 ± 11.0%, P < 0.01), and the rate of healthy tissue coverage tended to be higher (49.9 ± 17.7% vs. 42.1 ± 20.5%, P = 0.07) in the COMBO Plus stent compared to the XIENCE stent. Strut tissue coverage was more advanced in the COMBO Plus stent compared to the XIENCE stent at the very short-term period after implantation.

Artificial Intelligence-Based Algorithm for Stent Coverage Assessments

Background: Neointimal formation after stent implantation is an important prognostic factor since delayed healing may lead to stent thrombosis. In vivo, optical coherence tomography (OCT) can most precisely assess stent strut coverage. Since analyzing neointimal coverage is time-consuming, artificial intelligence (AI) may offer valuable assistance. This study presents the preliminary results of the AI-based tool's performance in detecting and categorizing struts as covered and uncovered. Methods: The algorithm was developed using the YOLO11 (You Only Look Once) neural networks. The first step was preprocessing, then data augmentation techniques were implemented, and the model was trained. Twenty OCT pullbacks were used during model training, and two OCT pullbacks were used in the final validation. Results: The presented tool's performance was validated against two analysts' consensus. Both analysts showed moderate intraobserver agreement (κ = 0.57 for analyst 1 and κ = 0.533 for analyst 2) and fair agreement with each other (κ = 0.389). The algorithm's detection of struts was satisfactory (a 92% positive predictive value (PPV) and a 90% true positive rate (TPR)) and was more accurate in recognizing covered struts (an 81% PPV and an 85% TPR) than uncovered struts (a 73% PPV and a 60% TPR). The agreement was κ = 0.444. Conclusions: The initial results demonstrated a good detection of struts with a more challenging uncovered strut classification. Further clinical studies with a larger sample size are needed to improve the proposed tool.

Serial Change and Clinical Impact of Irregular Protrusion in Lesions With Chronic Coronary Syndrome

BACKGROUND

The changes over time and effects on long-term clinical outcomes beyond 1 year of irregular protrusion (IP) in chronic coronary syndrome (CCS) remains unclear.

AIMS

This study aimed to assess the time-dependent change and long-term clinical impact of IP in CCS lesions.

METHODS

This study was a post hoc analysis of COLLABORATION study, which was a multicenter, prospective, observational study conducted from July 2018 to February 2020, assessing 1- and 12-month serial vessel responses after stent implantation using OCT and coronary angioscopy. Time-dependent change in the presence of IP was evaluated using the serial OCT examinations. The cumulative 3-year incidence of TLR was compared between the lesions with and without IP, as well as between those with and without residual IP at 1 month.

RESULTS

Among 107 lesions, IP was detected in post-OCT pullbacks in 38 (35.5%) lesions. Out of the 38 lesions, IP remained in 9 (23.7%) lesions at 1 month and existed in 2 (5.3%) lesions at 12 months. The cumulative 3-year incidence of TLR was significantly higher in IP group than in non-IP group (13.6% vs. 3.0%, p = 0.04). Similarly, it was significantly higher in lesions with residual IP at 1 month than those without (33.3% vs. 4.3%, p < 0.01). All residual IP at 1 month were composed of angioscopic yellow plaques and red thrombi.

CONCLUSIONS

The presence of IP decreased over time, but approximately one-fourth of IP remained at 1 month. IP and residual IP at 1 month were important post-stent OCT findings leading to long-term TLR in patients with CCS.

Titanium-nitride-oxide-coated vs. drug-eluting stents in acute coronary syndromes: an individual patient data meta-analysis

BACKGROUND AND AIMS

In acute coronary syndromes (ACS), vascular healing at the site of implantation of drug-eluting stents (DES) can be delayed. Titanium-nitride-oxide-coated stents (TiNOS) demonstrate faster strut coverage without the excessive intimal hyperplasia observed with bare metal stents. The 5-year outcomes of patients presenting with ACS, randomized to receive either TiNOS or DES, were compared.

METHODS

A systematic review and individual participant data meta-analysis of trials comparing TiNOS with DES for the treatment of ACS was conducted (PROSPERO: CRD42024514342). The primary endpoint was major adverse cardiac events (MACE) at 5 years, a composite of cardiac death (CD), myocardial infarction (MI), and ischaemia-driven target lesion revascularization (TLR). Pre-specified secondary endpoints included CD, MI, TLR, and stent thrombosis. Data were pooled using a mixed-effects Cox regression model with random slope and stratified baseline hazards.

RESULTS

Patient-level data (n = 2743) were obtained from three randomized controlled trials (TiNOS: n = 1620 vs. DES: n = 1123). After a median follow-up of 4.93 years, there was no significant difference in the primary endpoint between TiNOS and DES (12.6% vs. 16.2%; hazard ratio [HR] .82, 95% confidence interval [CI] .67-1.00, P = .051), mainly due to a similar rate of TLR (8.0% vs. 8.1%; HR 1.05, 95% CI .80-1.38, P = .733). However, TiNOS was associated with significantly lower rates of CD (1.5% vs. 3.7%; HR .46, 95% CI .26-.81, P = .007), MI (5.2% vs. 9.6%; HR .56, 95% CI .42-.75, P < .001), and stent thrombosis (1.1% vs. 3.8%; HR .30, 95% CI .17-.53, P < .001).

CONCLUSIONS

In ACS patients, TiNOS was associated with similar rates of MACE and TLR as compared with DES but significantly lower rates of CD, MI, and stent thrombosis.

Biodegradable Stents in the Treatment of Arterial Stenosis

Arterial diseases (ADs) are a significant health problem, with high mortality and morbidity rates. Endovascular interventions, such as balloon angioplasty (BA), bare-metal stents (BMSs), drug-eluting stents (DESs) and drug-coated balloons (DCBs), have made significant progress in their treatments. However, the issue has not been fully resolved, with restenosis remaining a major concern. In this context, bioresorbable vascular stents (BVSs) have emerged as a promising area of investigation. This manuscript includes articles that assess the use of BVSs. Studies have identified ongoing challenges, such as negative vascular remodeling and elastic recoil post-angioplasty, stent-related injury, and in-stent restenosis following BMS placement. While DESs have mitigated these issues to a considerable extent, their durable structures are unable to prevent late stent thrombosis and delay arterial recovery. BVSs, with their lower support strength and tendency towards thicker scaffolds, increase the risk of scaffold thrombosis. Despite inconsistent study results, the superiority of BVSs over DESs has not been demonstrated in randomized trials, and DES devices continue to be the preferred choice for most cases of arterial disease. Esprit BTK (Abbott Vascular) received approval from the US FDA for below-knee lesions in 2024, offering hope for the use of BVSs in other vascular conditions. Enhancing the design and thickness of BVS scaffolds may open up new possibilities. Large-scale and longer-term comparative studies are still required. This article aims to provide an overview of the use of biodegradable stents in the endovascular treatment of vascular stenosis.

Polymer free biolimus coated stents to treat acute ST-elevation myocardial infarction in Asian patients

BACKGROUND

Patients undergoing primary percutaneous coronary intervention (PPCI) for ST-segment-elevation myocardial infarction (STEMI) have a high thrombotic burden and often have a high bleeding risk (HBR). Asian patients have different patterns of thrombotic and bleeding risk from other populations which may be particularly relevant in the setting of PPCI for STEMI.

OBJECTIVES

To assess the safety and efficacy of the polymer free biolimus coated coronary stent (PF-BCS, BioFreedomTM, Biosensors International) in Asian STEMI patients.

METHODS

Patients with acute STEMI who received at least one PF-BCS were invited to participate after their index procedure. Follow-up was performed at 1, 4, and 12 months. The primary endpoint was the rate of target lesion failure (TLF) at 1 year. A performance goal was derived from the biolimus eluting stent arm of the COMFORTABLE AMI study which was the only prior dedicated study of biolimus eluting stents in patients with STEMI.

RESULTS

A total of 914 patients with STEMI were enrolled. Mean patient age was 60 ± 13 years, diabetes was present in 23.2% and 43% were active smokers. According to the ARC definition, 12.4% of the patients were HBR. TLF rate was 2.54% [95% CI: 1.52-3.56], p-value for non-inferiority <0.0001, p-value for superiority = 0.0004). The rate of definite/probable stent thrombosis was 0.44% [95% CI: 0.16-1.16]. There was a trend toward more BARC 3 to 5 bleeding in ARC-HBR patients (3.69% vs 1.46%, HR = 2.74, [95% CI: 0.87-8.62], p = 0.07).

CONCLUSIONS

In Asian patients undergoing PPCI for STEMI and treated with variable durations of DAPT, the use of a PF-BCS was associated with low rates of TLF and stent thrombosis (NCT03609346).

Comparison of Efficacy and Safety Between Drug-Coated Balloons Versus Drug-Eluting Stents in the Treatment of De Novo Coronary Lesions in Large Vessels: A Study-Level Meta-Analysis of Randomized Control Trials

BACKGROUND

Drug-coated balloons (DCB) can be used as an alternative to drug-eluting stents (DES) in patients with de novo small vessel coronary artery disease. This study aims to assess the efficacy and safety of solely using DCB versus DES in percutaneous coronary intervention (PCI) for de novo coronary lesions in large vessels.

METHOD

A database search was conducted using PubMed, EMBASE, Cochrane Library, and http://Clinicaltrials.gov for trials comparing DCB only with DES in treating de novo coronary lesions in large vessels. Efficacy outcomes included coronary angiography (CAG), follow-up minimal lumen diameter (MLD), and late luminal loss (LLL). Safety outcomes included target lesion failure [TLF: cardiac death, myocardial infarction (MI), target lesion revascularization (TLR)] and their individual components.

RESULTS

We included seven randomized control trials (RCTs) with 816 patients, of which 422 and 394 patients were in the DCB and DES groups, respectively. MLD measured during the 6-12 months follow-up in the DCB group was statistically significantly smaller than in the DES group (MD -0.21, 95% CI -0.34 to -0.07, P = 0.003, I2 = 52%). LLL measured at 6-12 months follow-up was statistically significantly lower in the DCB group than in the DES group (MD -0.13, 95% CI -0.22 to -0.05, P = 0.003, I2 = 60%). TLF, cardiac death, MI, and TLR, were not statistically significantly different between the two groups.

CONCLUSION

Use of DCB was associated with less LLL at 6-12 months than DES and was not associated with any increase in adverse clinical events. This data suggests DCB are as effective in treating de novo coronary lesions in large vessels as DES.

The influence between plaque rupture and non-plaque rupture on clinical outcomes in patients with ST-segment elevation myocardial infarction after primary percutaneous coronary intervention: a prospective cohort study

BACKGROUND

Coronary atherosclerosis can lead to acute clinical events upon atherosclerotic plaque rupture (PR) or erosion and arterial thrombus formation. Identifying the effect of distinct plaque characteristics on clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) is critical for clinical therapy. Our goal was to ascertain the correlation between clinical outcome, long-term prognosis, and morphological plaque characteristics in STEMI.

METHODS

The data used in this prospective cohort research came from a prior multicenter prospective cohort study (ChiCTR1800019923). One hundred and thirteen consecutive STEMI patients were involved in our cohort study. Patients with STEMI who received primary percutaneous coronary intervention (pPCI) within 24 hours of symptom onset were included in the study and divided into two groups according to plaque characteristics derived from intravascular ultrasound (IVUS): a PR group and a non-PR group. The primary outcome was the incidence of no reflow or slow flow, the secondary outcome was major adverse cardiac events (MACEs) at 1-year follow-up.

RESULTS

This study enrolled 113 consecutive patients with STEMI [mean age 56 (range, 49-65.5) years; males 90.27%]. Of the 113 patients, PR was found in 93 (82.3%), while non-PR was found in 20 (17.7%). The PR group had a higher rates of plaque eccentricity index (64.28%±22.69% vs. 60.08%±15.54%; P=0.045), higher rates of lipid pool-like images (62.37% vs. 30.00%; P=0.008), and higher rates of tissue prolapse (22.95% vs. 13.33%; P=0.01). Compared with that in the non-PR group, the incidence of no reflow or slow flow was higher in the PR group after pPCI (26.88% vs. 5.00%; P=0.04). Multivariable logistic regression showed that PR [odds ratio (OR) =8.188; 95% confidence interval (CI): 1.020-65.734; P=0.048] was an independent predictor of no reflow or slow flow. Survival analysis revealed no significant differences in MACE incidence between the two groups at 1-year follow-up (7.61% vs. 10.00%; P=0.66). Furthermore, 29 patients with PR were treated without stenting, most of them were free of MACEs (27/29). MACE between subgroups of stenting and non-stenting had no significant differences (7.94% vs. 6.90%; P=0.86) in the PR group.

CONCLUSIONS

In comparison to patients with non-PR, PR were not associated with the risk of recurrent myocardial infarction (MI), revascularization, heart failure, or cardiac death at 1-year follow-up, while associated with an increased incidence of no reflow or slow flow during pPCI. This observation would be considered while risk stratification and dealing with patients who have STEMI. Most patients with PR who were treated without stenting were MACE free. Further research should be conducted to determine whether interventional treatment without stenting is feasible for patients with STEMI and PR.

Pathological evaluation of predictors for delayed endothelial coverage after currently available drug-eluting stent implantation in coronary arteries: Impact of lesions with acute and chronic coronary syndromes

BACKGROUND

The optimal duration of dual antiplatelet therapy after currently available drug-eluting stent (DES) implantation to prevent stent thrombosis (ST) remains controversial. Delayed healing is frequently identified as a leading cause of ST in the early phase. However, a thorough pathological investigation into strut coverage after currently available DES implantation is lacking-a gap addressed in the current study.

METHODS

From our autopsy registry of 199 stented lesions, 4,713 struts from 66 currently available DES-stented lesions with an implant duration ≤370 days were histologically evaluated. Endothelial coverage was defined as the presence of luminal endothelial cells overlying struts and an underlying smooth muscle cell layer. The stented lesions were classified into acute coronary syndrome (ACS) (n = 40) and chronic coronary syndrome (CCS) (n = 26) groups and were compared. Endothelial coverage predictors were identified through logistic analysis.

RESULTS

Although ACS and CCS lesions presented comparable clinical characteristics, including age, sex, and cause of death, the latter exhibited a significantly higher prevalence of chronic kidney disease and hemodialysis than the former (33.3% vs. 65.2%; P = .02, 7.7% vs. 30.4%; P = .02). The poststent implant median duration was significantly shorter in ACS lesions than in CCS lesions (13 [IQR 5-26 days] vs. 40 [IQR 16-233 days]; P < .01). The endothelial coverage percentage was 3.5% at 30 days and 27.7% at 90 days after currently available DES implantation. Multivariable logistic regression analysis implicated implant duration of ≤90 days (odds ratio [OR], 0.009; 95% confidence interval [CI], 0.006-0.012; P < .01), superficial calcification (OR, 0.11; 95% CI, 0.07-0.17; P < .01), ACS culprit site (OR, 0.29; 95% CI, 0.09-0.94; P = .039), and circumferentially durable polymer-coated DES (OR, 0.32; 95% CI, 0.24-0.41; P < .01) as delayed endothelial coverage predictors.

CONCLUSIONS

Endothelial coverage was limited at 90 days after currently available DES implantation, and the ACS culprit site and circumferentially durable polymer-coated DES were identified as independent predictors of delayed endothelial coverage. Our findings suggest the importance of underlying plaque morphology and stent technology for vessel healing after such implantation.

Synthetic Flavonoid 3,7-Dihydroxy-Isoflav-3-Ene (DHIF) Reduces In-Stent Restenosis in an Atherosclerotic Watanabe Heritable Hyperlipidemic Rabbit Stent Model

Inflammation is a major component of the pathogenesis of atherosclerosis and the formation of in-stent restenosis (ISR). A novel flavonoid, DHIF, attenuates reactive oxygen species and nf-κB signaling and has potential to limit ISR via antioxidant action. While current drug eluting stents (DESs) perform well in clinical practice, new therapies to prevent ISR without dependance on cytotoxic drugs are warranted. Our objective was to test whether DHIF reduces ISR in a hyperlipidemic rabbit aorta model of ISR via attenuated inflammatory responses. WHHL rabbit aortas (n = 24) were denuded. Six weeks after injury, stents were implanted into the denuded aortas. DHIF was dissolved in carboxymethyl cellulose (CMC) and administered orally with two doses. CMC served as a control. The animals were sacrificed six weeks after stenting. ISR was evaluated from stent histomorphometry and immunohistology was used to assess the inflammatory and antiproliferative effects of the treatment. ISR was reduced from 20.9 ± 3.0% in controls to 15.2 ± 2.4% (p = 0.0009) and 16.4 ± 2.1% (p = 0.004) in the low- and high-dose groups, respectively. The neointimal area covered by macrophages was 32 ± 9.3% in the controls, 17.2 ± 5.9% (p = 0.005) in the low-dose group and 19.4 ± 7.9% (p = 0.008) in the high-dose group. DHIF significantly reduces ISR and local inflammation in stented arterial regions and could be used to reduce ISR when bare metal stents are used. Targeting local inflammation in the arterial wall may provide a way to reduce ISR in a clinical setting and further studies are warranted.

Early vascular healing after neXt-generation drug-eluting stent implantation in Patients with non-ST elevation acute Coronary syndrome: a randomized optical coherence Tomography imaging study (EXPECT)

Early vascular healing after drug-eluting stent (DES) implantation is associated with better outcomes and lower incidence of in-stent thrombosis. To examine vascular healing response in patients with non-ST elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI) guided by optical coherence tomography (OCT) versus angiography alone. Sixty patients were randomized 1:1:1 to OCT-guided PCI with 3-month OCT follow-up (O3 group, n = 20), angiography-guided PCI with 3-month OCT follow-up (A3 group, n = 20), or angiography-guided PCI with 6-month OCT follow-up (A6 group, n = 20). The primary endpoint was the proportion of covered struts at 3- or 6-month follow-up. The proportion of covered struts in the O3 group was significantly higher than in the A3 group (95.2% vs. 92.3%, p < 0.001), but lower than in the A6 group (95.2% vs. 97.4%, p < 0.001). The O3 group had a lower proportion of incomplete strut apposition (ISA) than the A3 group (0.46% vs. 0.76%, p = 0.006), and higher than the A6 group (0.46% vs. 0.27%, p = 0.018) at follow-up. The optimal cut-off value of ISA after implantation of DES for predicting stent coverage at 3 and 6-month follow-up was 200 μm and 308 μm, respectively. Only one patient experienced target lesion revascularization in the A3 group during a 3-year clinical follow-up. In patients with NSTE-ACS undergoing PCI with DES, OCT guidance achieved higher strut coverage compared with angiography guidance at 3-month follow-up. However, the difference in the strut coverage between the OCT-guided group and the angiography-guided group at 6 months indicates that the degree of endothelialization may be more time-dependent instead of invasive device guidance.

Randomized Trial of COBRA PzF Stenting to Reduce the Duration of Triple Therapy: The COBRA-REDUCE Trial

BACKGROUND

Patients with an indication for oral anticoagulation who undergo percutaneous coronary intervention require a combination of oral anticoagulation and antiplatelet therapy. The use of a coronary stent with a thromboresistant and pro-healing coating may allow an abbreviated duration of dual antiplatelet therapy (DAPT) without an increase in the risk of thromboembolic events.

METHODS

Patients with an indication for oral anticoagulation undergoing percutaneous coronary intervention were randomized to treatment with the COBRA polyzene F (PzF) stent followed by 14 days of DAPT or a Food and Drug Administration-approved new-generation drug-eluting stent followed by 3 or 6 months of DAPT. The bleeding coprimary end point was Bleeding Academic Research Consortium type ≥2 beyond 14 days (or after hospital discharge) until 6 months. The thromboembolic coprimary end point was the composite of all-cause death, myocardial infarction, definite or probable stent thrombosis, or ischemic stroke at 6 months. The trial hypothesis was that the COBRA PzF stent strategy would be superior with respect to bleeding events and noninferior with respect to thromboembolic events.

RESULTS

A total of 996 patients underwent randomization. The bleeding end point occurred in 37 of 475 patients (7.8%) in the COBRA PzF group and 47 of 482 patients (9.8%) in the control group (difference, -2.0 [95% CI, -5.6 to 1.6]; P=0.14). The thromboembolic end point occurred in 37 of 492 patients (7.5%) in the COBRA PzF group and 24 of 490 patients (4.9%) in the control group (difference, 2.6%; prespecified noninferiority margin 5%, upper limit of 1-sided 95% CI of the difference, 5.2%; Pnoninferiority=0.07).

CONCLUSIONS

In patients with an indication for oral anticoagulation undergoing percutaneous coronary intervention, treatment with the COBRA PzF stent plus 14 days of DAPT was not superior with respect to bleeding events and was not noninferior with respect to thromboembolic events at 6 months compared with treatment with standard Food and Drug Administration-approved drug-eluting stent plus 3 to 6 months of DAPT.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02594501.

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) in 2024

Primary Percutaneous Coronary Intervention (PCI) has significantly contributed to reducing the mortality of patients with ST-segment elevation myocardial infarction (STEMI) even in cardiogenic shock and is now the standard of care in most of Japanese institutions. The Task Force on Primary PCI of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) proposed an expert consensus document for the management of acute myocardial infarction (AMI) focusing on procedural aspects of primary PCI in 2018 and updated in 2022. Recently, the European Society of Cardiology (ESC) published the guidelines for the management of acute coronary syndrome in 2023. Major new updates in the 2023 ESC guideline include: (1) intravascular imaging should be considered to guide PCI (Class IIa); (2) timing of complete revascularization; (3) antiplatelet therapy in patient with high-bleeding risk. Reflecting rapid advances in the field, the Task Force on Primary PCI of the CVIT group has now proposed an updated expert consensus document for the management of ACS focusing on procedural aspects of primary PCI in 2024 version.

Impact of baseline yellow plaque assessed by coronary angioscopy on vascular response after stent implantation

BACKGROUND

The relationship between baseline yellow plaque (YP) and vascular response after stent implantation has not been fully investigated.

METHODS

This was a sub-analysis of the Collaboration-1 study (multicenter, retrospective, observational study). A total of 88 lesions from 80 patients with chronic coronary syndrome who underwent percutaneous coronary intervention were analyzed. Optical coherence tomography (OCT) and coronary angioscopy (CAS) were serially performed immediately and 11 months after stent implantation. YP was defined as the stented segment with yellow or intensive yellow color assessed by CAS. Neoatherosclerosis was defined as a lipid or calcified neointima assessed by OCT. OCT and CAS findings at 11 months were compared between lesions with baseline YP (YP group) and lesions without baseline YP (Non-YP group).

RESULTS

Baseline YP was detected in 37 lesions (42 %). OCT findings at 11 months showed that the incidence of neoatherosclerosis was significantly higher in the YP group (11 % versus 0 %, p = 0.028) and mean neointimal thickness tended to be lower (104 ± 43 μm versus 120 ± 48 μm, p = 0.098). CAS findings at 11 months demonstrated that the dominant and minimum neointimal coverage grades were significantly lower (p = 0.049 and P = 0.026) and maximum yellow color grade was significantly higher (p < 0.001) in the YP group.

CONCLUSIONS

Baseline YP affected the incidence of neoatherosclerosis as well as poor neointimal coverage at 11 months after stent implantation.

Clinical outcomes with biodegradable versus durable polymer drug-eluting stents in patients with ST-elevation myocardial infarction

BACKGROUND

Coronary drug-eluting stents (DES) built with either durable (DP) or biodegradable (BP) polymeric coatings have been largely tested and are extensively available for routine use. However, their comparative performance remains an open question, particularly in more complex subsets of patients.

AIMS

We evaluated the outcomes of patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI) using DP-DES versus BP-DES in a large multicenter real-world registry.

METHODS

The population comprised patients with STEMI treated with pPCI within 12 h of symptoms onset. Those treated with more than one DES who received different polymer types were excluded. The final cohort for analysis was selected after propensity score matching (PSM), computed to generate similar groups of DP DES versus BP DES. Primary endpoint was the incidence of major adverse cardiac events (MACE), defined as the composite of total death, myocardial infarction and target lesion revascularization at 2 years.

RESULTS

From January 2017 to April 2022, a total of 1527 STEMI patients underwent pPCI with a single DES type (587 DP-DES; 940 BP-DES). After PSM, 836 patients (418 patients in the DP-DES and 418 patients in the BP-DES groups), comprised the final study population. Both study groups had a similar baseline profile. Patients treated with BP-DES group had similar rates of MACE (15.3 % vs. 19.4 %, HR 0.69, 95 % CI 0.50-0.94, p = 0.022). Rates of target lesion revascularization was lower in BP DES group (0.7 % vs. 3.8 %, HR 0.17, 95 % CI 0.05-0.51, p = 0.006).

CONCLUSION

In a cohort of STEMI patients submitted to pPCI, BP and DP DES had similar rates of the primary outcome. Patients treated with BP DES, however, had a decreased incidence of TLR at after 2-year follow-up.

In-silico analysis of hemodynamic indicators in idealized stented coronary arteries for varying stent indentation

In this work, we investigate the effects of stent indentation on hemodynamic indicators in stented coronary arteries. Our aim is to assess in-silico risk factors for in-stent restenosis (ISR) and thrombosis after stent implantation. The proposed model is applied to an idealized artery with Xience V stent for four indentation percentages and three mesh refinements. We analyze the patterns of hemodynamic indicators arising from different stent indentations and propose an analysis of time-averaged WSS (TAWSS), topological shear variation index (TSVI), oscillatory shear index (OSI), and relative residence time (RRT). We observe that higher indentations display higher frequency of critically low TAWSS, high TSVI, and non-physiological OSI and RRT. Furthermore, an appropriate mesh refinement is needed for accurate representation of hemodynamics in the stent vicinity. The results suggest that disturbed hemodynamics could play a role in the correlation between high indentation and ISR.

Comparative effectiveness of ultrathin vs. standard strut drug-eluting stents: insights from a large-scale meta-analysis with extended follow-up

BACKGROUND

Newer generation ultrathin strut stents are associated with less incidence of target lesion failure (TLF) in patients undergoing percutaneous coronary intervention (PCI) in the short term. However, its long-term effect on different cardiovascular outcomes remains unknown.

OBJECTIVES

We aim to identify the effects of newer-generation ultrathin-strut stents vs. standard thickness second-generation drug-eluting stents (DES) on long-term outcomes of revascularization in coronary artery disease.

METHODS

We searched PubMed, Web of Science, Cochrane Library databases, and Scopus for randomized controlled trials (RCTs) and registries that compare newer-generation ultrathin-strut (< 70 mm) with thicker strut (> 70 mm) DES to evaluate cardioprotective effects over a period of up to 5 years. Primary outcome was TLF, a composite of cardiac death, target vessel myocardial infarction (TVMI) or target lesion revascularization (TLR). Secondary outcomes included the components of TLF, stent thrombosis (ST), and all-cause death were pooled as the standardized mean difference between the two groups from baseline to endpoint.

RESULTS

We included 19 RCTs and two prospective registries (103,101 patients) in this analysis. The overall effect on the primary outcome was in favor of second-generation ultrathin struts stents in terms of TLF at ≥ 1 year, ≥ 2 years, and ≥ 3 years (P value = 0.01, 95% CI [0.75, 0.96]), P value = 0.003, 95% CI [0.77, 0.95]), P value = 0.007, 95% CI [0.76, 0.96]), respectively. However, there was no reported benefit in terms of TLF when we compared the two groups at ≥ 5 years (P value = 0.21), 95% CI [0.85, 1.04]). Some of the reported components of the primary and secondary outcomes, such as TLR, target vessel revascularization (TVR), and TVMI, showed the same pattern as the TLF outcome.

CONCLUSION

Ultrathin-strut DES showed a beneficial effect over thicker strut stents for up to 3 years. However, at the 5-year follow-up, the ultrathin strut did not differ in terms of TLF, TLR, TVR, and TVMI compared with standard-thickness DES, with similar risks of patient-oriented composite endpoint (POCE), MI, ST, cardiac death, and all-cause mortality.

One-Year Outcomes of Biodegradable Polymer-Coated Sirolimus-Eluting Coronary Stent in Acute Coronary Syndrome: A Patient-Level Pooled Analysis from Two Indian Registries

INTRODUCTION

This pooled analysis was conducted to assess the clinical safety and performance of the Supra family (Sahajanand Medical Technologies Ltd., Surat, India) of sirolimus-eluting stents (SES) in patients with acute coronary syndromes (ACSs) including ST-segment elevation myocardial infarction (STEMI) from two real-world all-comers Indian registries at 1 year.

METHODS

We evaluated 1,824 patients with ACS who underwent percutaneous coronary intervention with the Supra family of SES from two real-world Indian registries (891 patients from T-Flex registry and 933 patients from Tetriflex real-world registry). The primary endpoint was the incidence of target lesion failure (TLF) defined as a composite of cardiac death, target-vessel myocardial infarction (TV-MI), and target lesion revascularization (TLR) at 1-year follow-up. The safety endpoint was stent thrombosis at 1-year follow-up.

RESULTS

Among a total of 1,824 patients with ACS, 689 (37.8%) patients presented with STEMI. In ACS and STEMI groups, 47.6% and 41.8% patients had multivessel disease, respectively. Of 2,128 lesions in ACS group, 76.7% lesions were type B2/C and 16.2% lesions were totally occluded. In the STEMI group, out of 784 treated lesions, 76.7% were type B2/C lesions and 21.9% were totally occluded. At 1-year follow-up, incidence of TLF was 5.3% (cardiac death: 0.9%, TV-MI: 2.5%, TLR: 1.9%) in patients with ACS and 6.2% (cardiac death: 1.4%, TV-MI: 2.1%, TLR: 2.7%) in patients with STEMI. The 1-year rate of definite/probable stent thrombosis was 0.3% and 0.7% in patients with ACS and STEMI, respectively.

CONCLUSION

This patient-level pooled analysis provides evidence for the safe and effective use of the Supra family of SES in complex patient populations such as ACS and even in STEMI with favorable rates of TLF and stent thrombosis at 1-year follow-up.

Comparison Among Ultra-Thin Coronary Stents: A Network Meta-Analysis

Ultrathin-strut drug-eluting stents (DES) have been related to potential improvement in stent-related outcomes compared with thicker-struts DES. However, comparisons among different ultrathin devices are lacking. All randomized controlled trials comparing ultrathin (struts thickness <70 µm) and thicker-struts DESs in an all-comers population were included. Target lesion failure (TLF), as defined by included trials, at 1-year follow-up was the primary end point. Overall mortality, myocardial infarction, target lesion revascularization (TLR), and stent thrombosis were the secondary end points. Arms of included trials were compared using network meta-analysis. Nine studies encompassing 20,081 patients were included, of which 9,509 patients had an ultrathin DES: Orsiro (evaluated in 7 arms with 8,086 patients), MiStent (1 arm with 703 patients), or Supraflex (1 arm with 720 patients). At 1-year follow-up, no significant differences were noted for TLF among these ultrathin DES. In particular, Orsiro was associated with a similar risk of TLF compared with Supraflex (risk rate 1.07, 95% confidence interval 0.59 to 1.78) and showed the highest probability of performing best in terms of TLF, myocardial infarction, and TLR. Ultrathin DES are all associated with a comparable risk of TLF compared with thicker-strut DES. In terms of TLR and TLF risk, Orsiro was the one with the highest probability of best performances, either compared with other ultrathin DES or to devices with thicker struts.

Efficacy and safety of durable versus biodegradable polymer drug-eluting stents in patients with acute myocardial infarction complicated by cardiogenic shock

The clinical impact of different polymer technologies in newer-generation drug-eluting stents (DESs) for patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) remains poorly understood. We investigated the efficacy and safety of durable polymer DESs (DP-DESs) compared with biodegradable polymer DESs (BP-DESs). A total of 620 patients who underwent percutaneous coronary intervention with newer-generation DESs for AMI complicated by CS was divided into two groups based on polymer technology: the DP-DES group (n = 374) and the BP-DES group (n = 246). The primary outcome was target vessel failure (TVF) during a 12-month follow-up, defined as a composite of cardiac death, myocardial infarction, or target vessel revascularization. Both the DP-DES and BP-DES groups exhibited low stent thrombosis rates (1.3% vs. 1.6%, p = 0.660). The risk of TVF did not significantly differ between the two groups (34.2% vs. 28.5%, hazard ratio [HR] 0.94, 95% confidence interval [CI] 0.69-1.29, p = 0.721). This finding remained consistent after adjustment with inverse probability of treatment weighting (28.1% vs. 25.1%, HR 0.98, 95% CI 0.77-1.27, p = 0.899). In AMI patients complicated by CS, the risk of a composite of cardiac death, myocardial infarction, or target vessel revascularization was not significantly different between those treated with DP-DESs and those treated with BP-DESs.Trial registration: RESCUE registry, https://clinicaltrials.gov/ct2/show/NCT02985008 , NCT02985008.

Nanotechnology in development of next generation of stent and related medical devices: Current and future aspects

Coronary stents have saved millions of lives in the last three decades by treating atherosclerosis especially, by preventing plaque protrusion and subsequent aneurysms. They attenuate the vascular SMC proliferation and promote reconstruction of the endothelial bed to ensure superior revascularization. With the evolution of modern stent types, nanotechnology has become an integral part of stent technology. Nanocoating and nanosurface fabrication on metallic and polymeric stents have improved their drug loading capacity as well as other mechanical, physico-chemical, and biological properties. Nanofeatures can mimic the natural nanofeatures of vascular tissue and control drug-delivery. This review will highlight the role of nanotechnology in addressing the challenges of coronary stents and the recent advancements in the field of related medical devices. Different generations of stents carrying nanoparticle-based formulations like liposomes, lipid-polymer hybrid NPs, polymeric micelles, and dendrimers are discussed highlighting their roles in local drug delivery and anti-restenotic properties. Drug nanoparticles like Paclitaxel embedded in metal stents are discussed as a feature of first-generation drug-eluting stents. Customized precision stents ensure safe delivery of nanoparticle-mediated genes or concerted transfer of gene, drug, and/or bioactive molecules like antibodies, gene mimics via nanofabricated stents. Nanotechnology can aid such therapies for drug delivery successfully due to its easy scale-up possibilities. However, limitations of this technology such as their potential cytotoxic effects associated with nanoparticle delivery that can trigger hypersensitivity reactions have also been discussed in this review. This article is categorized under: Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Nanomedicine for Cardiovascular Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Novel Stentless Strategy With Perfusion and Drug-Coated Balloons for Treating Acute Coronary Syndrome

Background

The challenge with the stentless strategy is that the method of optimal predilatation, and predictors of success remain unknown. Studies involving the stentless strategy prior to predilatation are limited. This study aimed to evaluate the long-term efficacy and safety of a new stentless strategy for treating acute coronary syndrome (ACS) using gradual, prolonged predilation with a perfusion balloon combined with a drug-coated balloon (DCB).

Methods

This was a single-center, prospective, single-arm study. A total of 30 patients with ACS underwent gradual, prolonged predilation using a perfusion balloon for 10 minutes, followed by additional dilation using a DCB. The primary end point was target vessel failure at 24 months. Secondary end points were a composite of acute end points, including stentless strategy success rate, procedural complications, final grade of coronary dissection, acute coronary occlusion, in-hospital major adverse cardiac events, and a chronic end point of target vessel failure at 24 months.

Results

A successful stentless strategy was achieved in 24 patients (80%), and 2 (8.3%) patients required ischemic-driven target lesion revascularization in the chronic phase. Six (20%) patients required stent placement due to type C dissection or acute recoil. No acute occlusion and in-hospital major adverse cardiac events were reported.

Conclusions

A novel stentless strategy using predilation with a perfusion balloon and DCB may be helpful for the revascularization of patients with ACS.

Long-term safety of ultrathin bioabsorbable-polymer sirolimus-eluting stents versus thin durable-polymer drug-eluting stents in acute coronary syndrome: A systematic review and meta-analysis

BACKGROUND

Because of the advancement of bioabsorbable polymers and thinner struts, bioabsorbable-polymer sirolimus-eluting stents (BP-SES) with ultrathin struts may be related to superior performance when compared to durable-polymer drug-eluting stents (DP-DES) with thin struts. Nonetheless, the long-term safety of ultrathin BP-SES in acute coronary syndrome (ACS) remains unknown.

METHODS

We sought to assess the long-term safety of ultrathin BP-SES in ACS patients, conducting a thorough meta-analysis of all relevant trials drawing a comparison between ultrathin BP-SES and contemporary thin DP-DES. Target lesion failure (TLF), which includes cardiac death (CD), target-vessel myocardial infarction (TV-MI), and clinically driven target lesion revascularization (CD-TLR) was considered the primary endpoint. Multiple databases comprising Embase, MEDLINE, Cochrane Library, and Pubmed were all thoroughly searched.

RESULTS

There were seven randomized controlled trials included in our study with 7522 randomized patients with ACS (BP-SES = 3888, DP-DES = 3634). TLF occurred in 371 (9.5% in BP-SES) and 393 (10.8% in DP-DES) patients, respectively, across a 40.7-month weighted mean follow-up, with no statistically significant group differences (risk ratio [RR]: 0.87; 95% confidence interval [CI]: 0.73-1.04; p = .12). Furthermore, no significant differences in cardiac death (RR: 0.96; 95% CI: 0.68-1.35; p = .81), TV-MI (RR: 0.63; 95% CI: 0.36-1.10; p = .10) and CD-TLR (RR: 0.77; 95% CI: 0.46-1.29; p = .32) were detected between two groups.

CONCLUSION

During a follow-up of 40.7 months, ultrathin BP-SES and thin DP-DES had a comparable risk of TLF and its individual components (CD, TV-MI, and CD-TLR), indicating that ultrathin BP-SES held at least the same safety and efficiency as thin DP-DES presented in patients with ACS.

Long-term outcomes with biodegradable polymer sirolimus-eluting stents versus durable polymer everolimus-eluting stents in ST-segment elevation myocardial infarction: 5-year follow-up of the BIOSTEMI randomised superiority trial

BACKGROUND

Biodegradable polymer sirolimus-eluting stents improve early stent-related clinical outcomes compared to durable polymer everolimus-eluting stents in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. The long-term advantages of biodegradable polymer sirolimus-eluting stents after complete degradation of its polymer coating in patients with STEMI remains however uncertain.

METHODS

BIOSTEMI Extended Survival (BIOSTEMI ES) was an investigator-initiated, follow-up extension study of the BIOSTEMI prospective, multicentre, single-blind, randomised superiority trial that compared biodegradable polymer sirolimus-eluting stents with durable polymer everolimus-eluting stents in patients with STEMI undergoing primary percutaneous coronary intervention at ten hospitals in Switzerland. All individuals who had provided written informed consent for participation in the BIOSTEMI trial were eligible for this follow-up study. The primary endpoint was target lesion failure, defined as a composite of cardiac death, target vessel myocardial re-infarction, or clinically indicated target lesion revascularisation, at 5 years. Superiority of biodegradable polymer sirolimus-eluting stents over durable polymer everolimus-eluting stents was declared if the Bayesian posterior probability for a rate ratio (RR) of less than 1 was greater than 0·975. Analyses were performed according to the intention-to-treat principle. The study was registered with ClinicalTrials.gov, NCT05484310.

FINDINGS

Between April 26, 2016, and March 9, 2018, 1300 patients with STEMI (1622 lesions) were randomly allocated in a 1:1 ratio to treatment with biodegradable polymer sirolimus-eluting stents (649 patients, 816 lesions) or durable polymer everolimus-eluting stents (651 patients, 806 lesions). At 5 years, the primary composite endpoint of target lesion failure occurred in 50 (8%) patients treated with biodegradable polymer sirolimus-eluting stents and in 72 (11%) patients treated with durable polymer everolimus-eluting stents (difference of -3%; RR 0·70, 95% Bayesian credible interval 0·51-0·95; Bayesian posterior probability for superiority 0·988).

INTERPRETATION

In patients undergoing primary percutaneous coronary intervention for STEMI, biodegradable polymer sirolimus-eluting stents were superior to durable polymer everolimus-eluting stents with respect to target lesion failure at 5 years of follow-up. The difference was driven by a numerically lower risk for ischaemia-driven target lesion revascularisation.

FUNDING

Biotronik.

Coronary arterial repair in patients with stable angina pectoris or acute coronary syndrome after ultrathin biodegradable polymer sirolimus-eluting stent implantation at 1-year follow-up by coronary angioscopy

BACKGROUND

Imaging modality-based evidence is limited that compares the extent of coronary arterial repair after percutaneous coronary intervention between patients with stable angina pectoris (SAP) and those with acute coronary syndrome (ACS).

METHODS

Between December 2018 and November 2021, a single-center, nonrandomized, observational study was conducted in 92 patients with SAP (n = 42) or ACS (n = 50), who were implanted with Orsiro sirolimus-eluting stent (O-SES) providing a hybrid (active and passive) coating and underwent 1-year follow-up by coronary angioscopy (CAS) after implantation. CAS assessed neointimal coverage (NIC), maximum yellow plaque (YP), and mural thrombus (MT).

RESULTS

Baseline clinical characteristics were comparable between the SAP and ACS groups. The follow-up periods were comparable between the two groups (390.1 ± 69.9 vs. 390.6 ± 65.7 days, p = 0.99). The incidences of MT at 1 year after implantation were comparable between the two groups (11.4% vs. 11.1%, p = 0.92). The proportions of "Grade 1" in dominant NIC grades were highest in both groups, and the proportions of maximum YP grades and MT were comparable between the two groups.

CONCLUSION

O-SES-induced coronary arterial repair at the site of stent implantation, irrespective of the types of coronary artery disease.

Very short-term tissue coverage of the CD34 antibody-covered sirolimus-eluting stent: an optical coherence tomography study

It is well known that patients with acute myocardial infarction (AMI) have delayed vessel healing despite accelerated endothelial progenitor cells (EPC) mobilization. The COMBO stent is a unique biodegradable-polymer sirolimus-eluting stent with an anti-CD34 antibody coating which captures EPC and potentially promotes vessel healing. However, there are limited data about strut tissue coverage at the very short-term period after COMBO stent implantation. This was a prospective study to investigate strut tissue coverage within 1 month after COMBO stent implantation using optical coherence tomography (OCT). Struts fully covered with tissue were defined as covered, and struts with distance from lumen surface longer than strut plus polymer thickness were defined as malapposed. Mean tissue thickness was measured only in apposed struts. A total of 8173 struts of 33 lesions in 32 patients were analyzed at an average of 19.8 ± 4.6 days after COMBO stent implantation. In lesion-level analysis, the rate of covered struts was 89.6 ± 7.2%, the rate of malapposed struts was 0.9 ± 2.0% and mean tissue thickness was 46.8 ± 14.3 µm. In comparison between AMI (n = 12) and non-AMI (n = 21) patients, there were no significant differences in the rate of covered struts (88.4 ± 8.4% vs. 90.2 ± 6.6%, p = 0.48) and mean tissue thickness (46.8 ± 13.7 µm vs. 46.9 ± 15.0 µm, p = 0.98). Multivariable analysis demonstrated that time from implantation to OCT imaging was significantly associated with mean tissue thickness. The COMBO stent had substantial tissue coverage at the very short-term period after implantation even in AMI patients, and follow-up time had an impact on vessel healing.

Titanium-Nitride-Oxide-Coated vs Everolimus-Eluting Stents in Acute Coronary Syndrome: 5-Year Clinical Outcomes of the TIDES-ACS Randomized Clinical Trial

Importance

Titanium-nitride-oxide (TiNO)-coated stents show faster strut coverage compared with drug-eluting stents without excessive intimal-hyperplasia observed in bare metal stents. It is important to study long-term clinical outcomes after treatment of patients with an acute coronary syndrome (ACS) by TiNO-coated stents, which are neither drug-eluting stents nor bare metal stents.

Objective

To compare the rate of main composite outcome of cardiac death, myocardial infarction (MI), or ischemia-driven target lesion revascularization at 5 years in patients with ACS randomized to receive either a TiNO-coated stent or a third-generation everolimus-eluting stent (EES).

Design, Setting, and Participants

This multicenter, randomized, controlled, open-label trial was conducted in 12 clinical sites in 5 European countries and enrolled patients from January 2014 to August 2016. Patients presenting with ACS (ST-segment elevation MI, non-ST-segment elevation MI, and unstable angina) with at least 1 de novo lesion were randomized to receive either a TiNO-coated stent or an EES. The present report analyzes the long-term follow-up for the main composite outcome and its individual components. Analysis took place between November 2022 to March 2023.

Main outcome

The primary end point was a composite of cardiac death, MI, or target lesion revascularization at 12-month follow-up.

Results

A total of 1491 patients with ACS were randomly assigned to receive either TiNO-coated stents (989 [66.3%]) or EES (502 [33.7%]). The mean (SD) age was 62.7 (10.8) years, and 363 (24.3%) were female. At 5 years, the main composite outcome events occurred in 111 patients (11.2%) in the TiNO group vs 60 patients (12%) in the EES group (hazard ratio [HR], 0.94; 95% CI, 0.69-1.28; P = .69). The rate of cardiac death was 0.9% (9 of 989) vs 3.0% (15 of 502) (HR, 0.30; 95% CI, 0.13-0.69; P = .005), the rate of MI was 4.6% (45 of 989) vs 7.0% (35 of 502) (HR, 0.64; 95% CI, 0.41-0.99; P = .049), the rate of stent thrombosis was 1.2% (12 of 989) vs 2.8% (14 of 502) (HR, 0.43; 95% CI, 0.20-0.93; P = .034), and the rate of target lesion revascularization was 7.4% (73 of 989) vs 6.4% (32 of 502) (HR, 1.16; 95% CI, 0.77-1.76; P = .47) in the TiNO-coated stent arm and in the EES arm, respectively.

Conclusion and relevance

In this study, patients with ACS had a main composite outcome that was not different 5 years after TiNO-coated stent or EES.

Trial Registration

ClinicalTrials.gov Identifier: NCT02049229.

The Supreme Biodegradable Polymer DES in Acute and Chronic Coronary Syndromes: A PIONEER III Substudy

Background

The PIONEER III trial demonstrated noninferiority of 12-month target lesion failure (TLF) with the Supreme DES (Sinomed), a thin-strut cobalt-chromium, biodegradable polymer, sirolimus-eluting stent, compared with a durable polymer, everolimus-eluting (XIENCE/PROMUS) stent (DP-EES). The relative safety and effectiveness of the Supreme DES in patients with acute coronary syndromes (ACS) and those with chronic coronary syndromes (CCS) is not known.

Methods

PIONEER III was a prospective, multicenter, international, 2:1 randomized trial stratified by clinical presentation. The primary end point was TLF at 12 months (a composite of cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization).

Results

A total of 1628 patients were enrolled, including 41% of patients with ACS (unstable angina and non-ST-elevation myocardial infarction) randomized to Supreme DES (n = 441) versus DP-EES (n = 232) and 59% of patients with CCS randomized to Supreme DES (n = 645) versus DP-EES (n = 310). Patients with ACS were younger, fewer presented with less diabetes, hypertension, and previous revascularization, but more were current smokers. The primary end point of TLF (6.4% vs 4.4%; P = .1), major adverse cardiac events (8.5% vs 6.5%; P = .16), and stent thrombosis (0.4% vs 0.9%; P = .25) at 12 months were similar in the ACS and CCS groups. There was no difference in TLF at 12 months between Supreme DES and DP-EES among patients with ACS (6.6% vs 6.0%; P = .89) and those with CCS (4.5% vs 4.3%; P = .83); interaction P = .51 for TLF by clinical presentation.

Conclusions

Compared with the DP-EES, the Supreme DES seemed safe and effective with a similar TLF at 12 months in both patients with ACS and those with CCS.

Early healing after treatment of coronary lesions by thin strut everolimus, or thicker strut biolimus eluting bioabsorbable polymer stents: The SORT-OUT VIII OCT study

AIMS

Early healing after drug-eluting stent (DES) implantation may reduce the risk of stent thrombosis. The aim of this study was to compare patterns of early healing after implantation of the thin strut everolimus-eluting Synergy DES (Boston Scientific) or the biolimus-eluting Biomatix Neoflex DES (Biosensors).

METHODS AND RESULTS

A total of 160 patients with the chronic or acute coronary syndrome were randomized 1:1 to Synergy or Biomatrix DES. Optical coherence tomography (OCT) was performed at baseline and at either 1- or 3-month follow-up. The primary endpoint was a coronary stent healing index (CSHI), a weighted index of strut coverage, neointimal hyperplasia, malapposition, and extrastent lumen. A total of 133 cases had OCT follow-up and 119 qualified for matched OCT analysis. The median CSHI score did neither differ significantly between the groups at 1 month: Synergy 8.0 (interquartile range [IQR]: 3.0; 14.0) versus Biomatrix 8.5 (IQR: 4.0; 15.0) (p = 0.47) nor at 3 months: Synergy 6.5 (IQR: 2.0; 13.0) versus Biomatrix 6.0 (IQR: 4.0; 11.0) (p = 0.83). Strut coverage was 84.6% (IQR: 72.0; 97.9) for Synergy versus 77.6% (IQR: 70.1; 90.3) for Biomatrix (p = 0.15) at 1 month and 90.3% (IQR 79.0; 98.8) (Synergy) versus 83.9% (IQR: 77.5; 92.6) (Biomatrix) (p = 0.068) at 3 months. Pooled 1- and 3-month coverage was 88.6% (IQR: 74.4; 98.4) for Synergy compared with 80.7% (IQR: 73.2; 90.8) for Biomatrix (p = 0.02).

CONCLUSIONS

The early healing response after treatment with the Synergy or Biomatrix DES did not differ significantly as determined by a healing index. The Synergy DES showed overall better early stent strut coverage.

The Ranger drug-coated balloon: advances in drug-coated technology for treatment of femoropopliteal segment arterial disease

Paclitaxel drug-coated balloons (DCBs) have been shown to improve patency and lower revascularization rates compared with plain old balloon angioplasty. DCBs continue to evolve by improving balloon-coating techniques that minimize the quantity of particles washed off into the bloodstream while maximizing drug retention and vascular-healing profile. Against this backdrop, it is clear that the future of antiproliferatives for the superficial femoral artery will focus on enhancements in device coating materials that will improve the efficiency of drug delivery. The Ranger DCB system recently gained US FDA approval for use. This review discusses the background of DCBs and how the Ranger DCB builds on these previous platforms based on experimental and clinical data.

Complex primary percutaneous coronary intervention with ultrathin-strut biodegradable versus thin-strut durable polymer drug-eluting stents in patients with ST-segment elevation myocardial infarction: A subgroup analysis from the BIOSTEMI randomized trial

BACKGROUND

Ultrathin-strut biodegradable polymer sirolimus-eluting stents (BP-SES) are superior to thin-strut durable polymer everolimus-eluting stents (DP-EES) with respect to target lesion failure (TLF) at 2 years among patients with ST-segment elevation myocardial infarction (STEMI). We sought to determine the impact of primary percutaneous coronary intervention (pPCI) complexity on long-term clinical outcomes with BP-SES versus DP-EES in STEMI patients.

METHODS

We performed a post hoc subgroup analysis from the BIOSTEMI (NCT02579031) randomized trial, which included individual data from 407 STEMI patients enrolled in the BIOSCIENCE trial (NCT01443104). STEMI patients were randomly assigned to treatment with ultrathin-strut BP-SES or thin-strut DP-EES, and further categorized into those undergoing complex versus noncomplex pPCI. Complex pPCI was defined by the presence of ≥1 of the following criteria: 3 vessel treatment, ≥3 stents implanted, ≥3 lesions treated, bifurcation lesion with ≥2 stents implanted, total stent length ≥60 mm, and/or chronic total occlusion treatment. The primary endpoint was TLF, a composite of cardiac death, target-vessel myocardial reinfarction, or clinically indicated target lesion revascularization, within 2 years.

RESULTS

Among a total of 1707 STEMI patients, 421 (24.7%) underwent complex pPCI. Baseline characteristics were similar between groups. At 2 years, TLF occurred in 14 patients (7.1%) treated with BP-SES and 25 patients (11.6%) treated with DP-EES (hazard ratio [HR]: 0.62; 95% confidence interval [CI]: 0.32-1.19; p = 0.15) in the complex pPCI group, and in 28 patients (4.4%) treated with BP-SES and 49 patients (8.2%) treated with DP-EES (HR: 0.54; 95% CI: 0.34-0.86; p = 0.008; p for interaction = 0.74) in the noncomplex pPCI group. Individual TLF components and stent thrombosis rates did not significantly differ between groups.

CONCLUSION

In a post hoc subgroup analysis from the BIOSTEMI randomized trial, ultrathin-strut BP-SES were superior to thin-strut DP-EES with respect to TLF at 2 years among STEMI patients undergoing both complex and noncomplex pPCI.

Angioscopic findings 1 year after percutaneous coronary intervention for chronic total occlusion

BACKGROUND

Chronic total occlusion (CTO) is a high-risk factor for stent thrombosis, but little is known about the difference in neointimal healing between CTO and non-CTO lesions regarding implanted stents. We investigated factors affecting neointimal healing after stent implantation for CTO and non-CTO lesions using angioscopy.

METHODS

We retrospectively evaluated 106 stents in 85 consecutive patients between March 2016 and July 2020. Their average age was 68 ± 11 years, and participants (73 male and 12 female) underwent follow-up angiography and angioscopy 1 year after percutaneous coronary intervention (PCI). The stents (n = 106) were divided into three groups according to the lesion status at the previous PCI: CTO (n = 17), acute coronary syndrome (ACS) (n = 35), and stable coronary artery disease without CTO or non-CTO (n = 54).

RESULTS

The neointimal stent coverage grade was significantly lower in the CTO and ACS groups than in the non-CTO group (0.4 ± 0.5, 0.9 ± 0.8, and 1.4 ± 0.8, respectively, p < 0.001). Thrombi were significantly more frequent in CTO and ACS than in non-CTO (71 %, 51 %, and 15 %, respectively, p < 0.001). The yellow grade in CTO was comparable to that in ACS but significantly higher in CTO than in non-CTO (CTO vs. ACS vs. non-CTO 1.5 ± 0.7, 1.4 ± 0.6, and 0.9 ± 0.7, respectively, p = 0.007).

CONCLUSIONS

Delayed healing occurs in stents implanted for CTO lesions. Longer dual-antithrombotic therapy may be beneficial.

Everolimus-eluting bioresorbable scaffold versus everolimus-eluting metallic stent in primary percutaneous coronary intervention of ST-segment elevation myocardial infarction: a randomized controlled trial

BACKGROUND

Primary percutaneous coronary intervention with implantation of a metallic drug-eluting stent (DES) is the standard treatment for patients presenting with ST-elevation myocardial infarction (STEMI). Implantation of a bioresorbable scaffold (BRS) during STEMI represents a novel strategy without intravascular metal.

OBJECTIVE

The aim of the study was to investigate 12-month healing response in an STEMI population after implantation of either the Absorb BRS or Xience DES (Abbott Vascular, USA).

METHODS

The present trial was a prospective, randomized, controlled, nonblinded, noninferiority study with planned inclusion of 120 patients with STEMI. Patients were randomly assigned 1:1 to treatment with Absorb BRS or Xience DES. Implantation result and healing response were evaluated by angiography and optical coherence tomography (OCT) at baseline and 12-month follow-up. The primary endpoint was minimum flow area (MFA) assessed at 12 months. Coronary stent healing index (CSHI) was calculated from OCT images.

RESULTS

Out of 66 included patients, 58 had follow-up OCT after 12 months, and 49 entered matched analysis. One death occurred in each group; none were stent-related. MFA was 5.13 ± 1.70 mm2 (95% CI, 4.44-5.82) in the BRS group compared with 6.30 ± 2.49 mm2 (95% CI, 5.22-7.37) (P = 0.06) in the DES group. Noninferiority could not be evaluated. CSHI for both groups had a median score of 3.

CONCLUSION

The DES group performed numerically better in primary and secondary endpoints, but the CSHI showed good stent healing in both groups.

Pathologic characteristics of human venous in-stent stenosis and stent occlusion

OBJECTIVE

The objective of this study was to determine the pathologic features of venous in-stent stenosis over time occurring in bare metal stents.

METHODS

Endovascular biopsy samples were obtained prospectively from venous bare metal stents implanted in 2009 through 2018. All samples were formalin-fixed, paraffin-embedded and stained with hematoxylin and eosin. Samples were examined by a cardiovascular pathologist to estimate the amount of its constituent components, which included fresh thrombus, organizing thrombus, old thrombus, or diffuse intimal thickening (DIT), and pathologic features including calcification, neovascularization, and hemosiderin deposition. This pathologic characterization was correlated with time following stent implantation to discern time-dependence of pathologic evolution of in-stent stenosis using both descriptive statistics and binary logistic regression.

RESULTS

A total of 254 post-stent venograms with biopsies of in-stent contents from 148 unique patients were studied. Fresh thrombus and organizing thrombus were both present across all studied time intervals. Old thrombus was seen beginning at approximately 2 weeks and DIT at approximately 4 weeks. Calcification was a rare finding encountered at later time intervals. The prevalence of each component varied with time: the probability of encountering fresh thrombus (P = .010) and organizing thrombus (P = .008) decreased over time. By contrast, the probability of finding DIT (P = .002) and calcifications (P < .001) increased over time. The presence of old thrombus, neovascularization, or hemosiderin did not demonstrate time dependence. Diffuse intimal thickening was frequently seen along with organizing thrombus as well as independently, and in many instances, these two features were directly merged.

CONCLUSIONS

The evolution of human venous in-stent restenosis appears to follow a time-dependent course, suggesting a possible progressive evolution from fresh and organizing thrombus to DIT. Contrasted with the literature on arterial in-stent restenosis, vein in-stent restenosis may have an increased thrombus prevalence (both organizing and old thrombus). DIT is a primary feature of late in-stent stenosis and may explain in part why many of these lesions may not respond to thrombolytic or anticoagulant treatment alone.

Determinants and long-term outcomes of largely uncovered struts in thin-struts drug-eluting stents assessed by optical coherence tomography

BACKGROUND

Uncovered struts are a determinant of stent failure. The impact of plaque composition and procedural factors on the occurrence, evolution, and outcomes of uncovered struts in a high-risk setting has not been investigated.

OBJECTIVE

To investigate the determinants and long-term clinical impact of largely uncovered struts (LUS) in thin-struts drug-eluting stents (DES) implanted in complex lesions by intracoronary optical coherence tomography (OCT).

METHODS

Ninety patients with multivessel disease undergoing staged complete revascularization were randomly assigned to bioabsorbable or durable polymer DES. OCT were serially performed during the index procedure, at 3- and 18-month follow-up, and analyzed by an independent core lab. Struts were defined uncovered by OCT if no tissue was visible above the struts. LUS were defined as ≥30% of uncovered struts at 3-month follow-up. Clinical outcomes were the occurrence of target vessel failure (TVF) and major adverse cardiac and cerebrovascular events (MACCE) at 5-year follow-up.

RESULTS

LUS occurred in 31 patients (34.4%) regardless of stent platform. At 5 years, no differences were observed in the rate of TVF (12.7% vs. 13.4%; p = 0.91) and MACCE (23.9% vs. 24.9%; p = 0.88) between the two groups. At multivariate logistic regression, plaque rupture, mean lumen diameter, proximal reference vessel area, and maximum stent deployment pressure were independent predictors of LUS.

CONCLUSIONS

LUS are a frequent finding in complex coronary lesions treated with thin-struts DES, especially in the presence of plaque rupture. However, in this study, no significant safety signal related to LUS emerged in long-term follow-up.

Efficacy and safety of dual antiplatelet therapy after percutaneous coronary drug-eluting stenting: A network meta-analysis

BACKGROUND

To evaluate the efficacy and safety of dual antiplatelet regimens after coronary drug-eluting stenting by network meta-analysis (NMA).

METHODS

PubMed, The Cochrane Library, Embase, and Web of Science databases were electronically searched to collect randomized controlled trials (RCTs) of the comparison of different dual antiplatelet regimens after coronary drug-eluting stenting from inception to September 1st, 2021. Two reviewers independently screened literature, extracted data, and assessed the risk bias of included studies. Stata 16.0 software was used for NMA.

RESULTS

A total of 27 RCTs involving 79,880 patients were included. The results of NMA: in terms of myocardial infarction (MI), other 3 interventions were higher than the long-term dual antiplatelet therapy (L-DAPT) (the standard dual antiplatelet therapy [Std-DAPT] [odds ratio [OR] = 1.82, 95%confidence interval [CI]: 1.49-2.21), the aspirin monotherapy after short-term dual antiplatelet therapy (S-DAPT + As) (OR = 2.06, 95%CI: 1.57-2.70), the P2Y12 inhibitor monotherapy after short-term dual antiplatelet therapy (S-DAPT + P2Y12) (OR = 1.71, 95%CI: 1.29-2.28)]. In terms of stent thrombosis, other 3 interventions were higher than L-DAPT [Std-DAPT (OR = 2.18, 95%CI: 1.45-3.28), S-DAPT + As (OR = 2.32, 95%CI: 1.52-3.54), S-DAPT + P2Y12 (OR = 2.31, 95%CI: 1.22-4.36)]. There was no statistically significant difference among the 4 interventions in prevention of stroke and all-cause mortality (P > .05). In terms of cardiovascular and cerebrovascular adverse events, other 3 interventions were higher than L-DAPT (Std-DAPT [OR = 1.28, 95%CI: 1.12-1.45], S-DAPT + As [OR = 1.27, 95%CI: 1.09-1.48], S-DAPT + P2Y12 [OR = 1.24, 95%CI: 1.01-1.52]). In terms of safety, bleeding rate of other 3 interventions were lower than L-DAPT (Std-DAPT [OR = 0.67, 95%CI: 0.52-0.85], S-DAPT + As [OR = 0.51, 95%CI: 0.39-0.66], S-DAPT + P2Y12 [OR = 0.36, 95%CI: 0.26-0.49]). Two interventions were lower than L-DAPT (S-DAPT + As [OR = 0.77, 95%CI: 0.65-0.90], S-DAPT + P2Y12 [OR = 0.54, 95%CI: 0.44-0.66]). S-DAPT + As was higher than L-DAPT (OR = 1.42, 95%CI: 1.10-1.83).

CONCLUSIONS

S-DAPT + P2Y12 has the lowest bleeding risk, while L-DAPT has the highest bleeding risk. In the outcome of MI, stent thrombosis, and cardiovascular and cerebrovascular adverse events, L-DAPT has the best efficacy. In the outcome of stroke and all-cause mortality, the 4 interventions were equally effective.

The Residual Lipid-Rich Coronary Atheroma Behind the Implanted Newer-Generation Drug-Eluting Stent and Future Stent-Related Event Risks

BACKGROUND

Lipid-rich plaque is an important substrate that causes future coronary events. However, the clinical implications of underlying plaque characteristics in coronary lesions after newer-generation drug-eluting stent (DES) implantation remain unknown.

METHODS

The current study analyzed 445 target lesions after newer-generation DES implantation in 416 patients with coronary artery disease (CAD) (chronic coronary syndrome/acute coronary syndrome = 264/181) from the REASSURE-NIRS multicentre registry. Near-infrared spectroscopy (NIRS) imaging was used to evaluate maximum lipid core burden index after stent implantation in target lesions (residual maxLCBI4mm). The primary and secondary outcomes were 3-year lesion-oriented clinical outcomes (LOCO): cardiac death, nonfatal target-lesion-related myocardial infarction (MI), or ischemia-driven target-lesion revascularization (ID-TLR) and patient-oriented clinical outcomes (POCO): all-cause death, nonfatal MI, or ID unplanned revascularization. Outcomes were compared by residual maxLCBI4mm tertile.

RESULTS

Median residual maxLCBI4mm was 183; 16% of lesions had residual maxLCBI4mm > 400. Higher residual maxLCBI4mm was not associated with a greater likelihood of LOCO or POCO during the observational period (LOCO, log-rank P = 0.76; POCO, log-rank P = 0.84). Mixed-effects logistic regression demonstrated that residual maxLCBI4mm does not predict LOCO (odds ratio [OR], 1.000; 95% confidence interval [CI], 0.997-1.003; P = 0.95). There was no significant relationship between residual maxLCBI4mm and POCO (OR, 1.001; 95% CI, 0.999-1.002; P = 0.30).

CONCLUSIONS

Residual maxLCBI4mm is not associated with LOCO or POCO in patients with CAD after newer-generation DES implantation. Our findings suggest that NIRS-derived underlying lipid-rich plaque is not associated with the risk of stent-related events and patient-based outcomes in patients with CAD who have received newer-generation DESs.

Safety and Efficacy of Ultra Short-Duration Dual Antiplatelet Therapy After Percutaneous Coronary Interventions: A Meta analysis of Randomized Controlled Trials

INTRODUCTION

Dual antiplatelet therapy (DAPT) is required after percutaneous coronary intervention (PCI) to reduce stent thrombosis, but DAPT increases bleeding risks. The optimal duration of DAPT that provides the maximum protective ischemic effect along with the minimum bleeding risk is unclear. This is the first meta-analysis comparing outcomes for 1-month versus longer DAPT strategies following PCI.

METHODS

We searched PubMed, Cochrane, and ClinicalTrials.gov databases (from inception to October 2021) for randomized controlled trials (RCTs) that compared 1-month duration versus > 1-month duration of DAPT following PCI. We used a random-effects model to calculate risk ratio (RR) with 95% confidence interval (CI). The co-primary outcomes for study selection were all-cause mortality, major bleeding, and stent thrombosis. Secondary outcomes included myocardial infarction (MI), cardiovascular mortality, ischemic stroke and target vessel revascularization.

RESULTS

A total of five RCTs were included [n=29,355; 1-month DAPT(n=14,662) vs > 1-month DAPT (n=14,693)]. There was no statistically significant difference between the two groups in terms of all-cause mortality (RR 0.89; 95% CI 0.78-1.03; p = 0.12) and stent thrombosis (RR 1.07; 95% CI 0.80-1.43; p = 0.65). Similarly, there were no significant differences in MI, cardiovascular mortality, ischemic stroke, and target vessel revascularization. The rate of major bleeding was significantly lower in the group treated with DAPT for 1-month (RR 0.74; 95% CI 0.56-0.99, p = 0.04).

CONCLUSION

There is no difference in all-cause mortality, cardiovascular mortality, MI, stent thrombosis, ischemic stroke and target vessel revascularization with 1-month of DAPT following PCI with contemporary drug eluting stents compared to longer DAPT duration.

3D Printed Bioreactor Enabling the Pulsatile Culture of Native and Angioplastied Large Arteries

Routine interventions such as balloon angioplasty, result in vascular activation and remodeling, often requiring re-intervention. 2D in vitro models and small animal experiments have enabled the discovery of important mechanisms involved in this process, however the clinical translation is often underwhelming. There is a critical need for an ex vivo model representative of the human vascular physiology and encompassing the complexity of the vascular wall and the physical forces regulating its function. Vascular bioreactors for ex vivo culture of large vessels are viable alternatives, but their custom-made design and insufficient characterization often hinders the reproducibility of the experiments. The objective of the study was to design and validate a novel 3D printed cost-efficient and versatile perfusion system, capable of sustaining the viability and functionality of large porcine arteries for 7 days and enabling early post-injury evaluations. MultiJet Fusion 3D printing was used to engineer the EasyFlow insert, converting a conventional 50 ml centrifuge tube into a mini bioreactor. Porcine carotid arteries either left untreated or injured with an angioplasty balloon, were cultured under pulsatile flow for up to 7 days. Pressure, heart rate, medium viscosity and shear conditions were adjusted to resemble arterial in vivo hemodynamics. Tissue viability, cell activation and matrix remodeling were analyzed by immunohistochemistry, and vascular function was monitored by duplex ultrasound. Culture conditions in the EasyFlow bioreactor preserved endothelial coverage and smooth muscle organization and extracellular matrix structure in the vessel wall, as compared to static culture. Injured arteries presented hallmarks of early remodeling, such as intimal denudation, smooth muscle cell disarray and media/adventitia activation in flow culture. Duplex ultrasound confirmed continuous pulsatile blood flow conditions, dose-dependent vasodilator response to nitroglycerin in untreated vessels and impaired dilator response in angioplastied vessels. The scope of this work is to validate a low-cost, robust and reproducible system to explore the culture of native and injured large arteries under pulsatile flow. While the study of vascular pathology is beyond the scope of the present paper, our system enables future investigations and provides a platform to test novel therapies and devices ex vivo, in a patient relevant system.

A Randomized Comparison of the Healing Response Between the Firehawk Stent and the Xience Stent in Patients With ST-Segment Elevation Myocardial Infarction at 6 Months of Follow-Up (TARGET STEMI OCT China Trial): An Optical Coherence Tomography Study

Background

The healing response of the Firehawk stent in patients with ST-segment elevation myocardial infarction (STEMI) remains unclear.

Aim

We compared the vascular healing of a biodegradable polymer sirolimus-eluting stent (Firehawk) vs. a durable polymer everolimus-eluting stent (Xience) at 6 months after percutaneous coronary intervention (PCI) in patients with STEMI.

Methods

In this prospective, multicenter, randomized, non-inferiority study, patients within 12 h of STEMI onset were randomized in a ratio of 1:1 to receive Firehawk or Xience stents. Optical coherence tomography (OCT) follow-up was performed 6 months after the index procedure and assessed frame by frame. The primary endpoint was the neointimal thickness (NIT) at 6 months evaluated by OCT. The safety endpoint was target lesion failure (TLF) at 12 months.

Results

The Firehawk stent was non-inferior to the Xience stent in terms of the neointimal thickness (73.03 ± 33.30 μm vs. 78.96 ± 33.29 μm; absolute difference: −5.94 [one-sided 95% lower confidence bound: −23.09]; P_{non−inferiority} < 0.001). No significant difference was observed between the Firehawk and Xience groups regarding the percentage of uncovered struts (0.55 [0.08, 1.32]% vs. 0.40 [0.21, 1.19]%, P = 0.804), the percentage of malapposed struts (0.17 [0.00, 1.52]% vs. 0.17 [0.00, 0.69]%, P = 0.662), and the healing score (1.56 [0.23, 5.74] vs. 2.12 [0.91, 3.81], P = 0.647). At 12 months, one patient in the Firehawk group experienced a clinically indicated target lesion revascularization. No other TLF events occurred in both groups. Independent risk factors of the NIT included body mass index, hyperlipidemia, B2/C lesions, thrombus G3–G5, thrombus aspiration, and postdilation pressure.

Conclusion

In patients with STEMI, Firehawk was non-inferior to Xience in vascular healing at 6 months. Both stents exhibited nearly complete strut coverage, moderate neointimal formation, and minimal strut malapposition.

Clinical Trial Number

NCT04150016.

Early vascular healing of ultra-thin strut polymer-free sirolimus-eluting stents in acute coronary syndrome: USUI-ACS study

Ultra-thin strut polymer-free sirolimus-eluting stent (UPF-SES) have two novel characteristics, ultra-thin strut and polymer-free coating, which have the potential to achieve early re-endotherialization. However, a little is known whether early vascular healing of UPF-SES can be achieved in patients with acute coronary syndrome (ACS). The aim of this study was to evaluate the vascular healing after an implantation of UPF-SES in patients with ACS using optical coherence tomography (OCT) at 3 months after the stent implantation. From September 2020 and January 2021, a total of 31 consecutive patients presenting with ACS who underwent OCT-guided percutaneous coronary intervention (PCI) and 3 month follow-up OCT examination were enrolled in the USUI-ACS study. The endpoints of this study were neointimal strut coverage, malapposition, and mean neointimal hyperplasia (NIH) thickness at 3 month follow-up. Over a mean follow-up of 91 days after the initial PCI, the follow-up OCT was examined. The median percentage of covered struts was 98.4% and malapposed struts 0%, and the mean NIH thickness was 80 μm. UPF-SES exhibited an excellent early vascular healing at 3 months in patients with ACS.

New Ultrasound-Controlled Paclitaxel Releasing Balloon vs. Asymmetric Drug-Eluting Stent in Primary ST-Segment Elevation Myocardial Infarction - A Prospective Randomized Trial

BACKGROUND

Application of drug-coated balloons (DCBs) is popular for the treatment of percutaneous coronary intervention (PCI). A new DCB has been designed as ultrasound-controlled paclitaxel releasing. This study was conducted to determine whether a DCB-only strategy has a similar safety profile and equal angiographic and clinical outcomes to DES implantation in primary ST-elevation myocardial infarction (STEMI) patients, as well as determine the efficiency and safety of this new DCB.

METHODS AND RESULTS

Overall, 184 pretreated STEMI patients were randomized into DCB and DES groups with a 1:1 allocation. The main study end-point was late lumen loss (LLL) during the 9 months after PCI. Late lumen loss was reported to be 0.24±0.39 mm in the DCB group and 0.31±0.38 mm in the DES group (P=0.215). Diameter stenosis was 28.27±15.35% in the DCB group and 25.73±15.41% in the DES group (P=0.312). Major adverse cardiovascular events (MACEs) were reported in 3 patients (3.4%) in the DCB group and 4 patients (4.7%) in the DES group (P=0.718). TLR and TVR in the DCB group was 2.3%, 3.4% and 2.4%, 3.5% in the DES group (P=1.000), respectively. No cardiac death and stent thrombosis (ST) was found in the DCB group at 12 months clinical follow up.

CONCLUSIONS

The DCB-only strategy showed good angiographic and clinical outcomes in the 9- and 12-month follow-up periods, respectively. The VasoguardTM DCB is safe and feasible to treat STEMI patients.

Early vascular healing after implantation of the polymer-free biolimus-eluting stent or the ultrathin strut biodegradable polymer sirolimus-eluting stent in patients with ST-segment elevation myocardial infarction

OBJECTIVE

To evaluate the difference in early vascular healing between the ultrathin-strut biodegradable-polymer sirolimus-eluting Orsiro stent (O-SES) and the polymer-free biolimus-A9-eluting BioFreedom stent (BF-BES), assessed with optical coherence tomography (OCT) after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarctions (STEMIs).

METHODS

Eighty patients with STEMI who underwent primary PCI were randomly allocated 1:1 to treatment with BF-BES or O-SES. OCT was acquired after PCI and at 1-month follow-up. The primary endpoint was 1-month OCT-assessed vascular healing index based on the presence of uncovered and malapposed stent struts and intraluminal filling defects where low vascular healing index indicated favorable vascular healing.

RESULTS

At 1-month, the vascular healing index was similar in O-SES 11.5 [interquartile range (IQR) 9.5-17.5], compared to BF-BES 11.5 (IQR 7.1-12.5; P = 0.14). Percentage of uncovered struts [O-SES 31.5% (IQR 20.7-41.9), P = 0.43] vs. BF-BES 27.8% (IQR 19.4-41.9; P = 0.44), and median volume of neointimal hyperplasia [O-SES 4.9 mm3 (IQR 1.4-13.1) vs. BF-BES 7.1 mm3 (IQR 2.8-17.0), P = 0.18] did not differ significantly between the two stent groups. Complete coverage was not observed in any of the stents. The percentages of stents with malapposition did not differ significantly (O-SES 87.1% vs. BF-BES 71.4%, P = 0.14) whereas percentage of malapposed struts [O-SES 3.5% (IQR 0.8-5.5) vs. BF-BES 0.8% (IQR 0.0-1.8), P = 0.003] was lower in the BF-BES group.

CONCLUSION

In patients with STEMI, the drug-coated BF-BES and the thin strut O-SES had similar vascular healing index at 1-month. However, the thin O-SES struts were more often malapposed.