Rationale and design of a randomized study comparing the agent drug coated balloon to plain old balloon angioplasty in patients with In-stent restenosis.

BACKGROUND: Drug-coated balloon (DCB) technology was developed as an alternative treatment for obstructive coronary artery disease (CAD) and in-stent restenosis (ISR). Management of coronary ISR is clinically challenging and frequently encountered in practice. The Agent DCB uses an inactive excipient to effectively deliver a targeted, therapeutic dose of paclitaxel to the vessel wall. STUDY DESIGN: AGENT IDE is a prospective, multicenter, randomized controlled trial to evaluate superiority of the Agent DCB to balloon angioplasty in treating patients with ISR. A total of 480 patients with ISR of a previously treated lesion length <26 mm and reference vessel diameter >2.0 mm to ≤4.0 mm will be initially randomized. Subjects presenting with recent myocardial infarction (MI), complex lesions, or thrombus in the target vessel will be excluded. An adaptive group sequential design with one formal interim analysis for sample size re-estimation will be conducted, and the sample size may be increased to a maximum of 600 subjects. The primary endpoint is the rate of 12-month target lesion failure (TLF; composite of any ischemia-driven revascularization of the target lesion (TLR), target vessel related MI, or cardiac death) and will be tested for superiority in the test arm against the control. Functional status and general health-related quality of life will be measured by changes in the EQ-5D scores. Subjects will be followed for 5 years following the index procedure. CONCLUSION: This study will prospectively evaluate the safety and efficacy of Agent DCB in patients treated for coronary ISR.

Differences in clinical outcomes between pre- and post-marketing clinical study following paclitaxel-coated balloon catheter treatment for coronary in-stent restenosis: from the Japanese regulatory viewpoint.

In 2013, a drug-coated balloon catheter (DCB) (SeQuent Please) for the treatment of coronary in-stent restenosis (ISR) was approved in Japan. The pre-marketing Japan domestic NP001 study demonstrated better outcomes of the DCB (n = 138) compared to plain balloon angioplasty (n = 72). After the introduction to marketing, a post-marketing surveillance (PMS) (n = 396) was conducted to evaluate the safety and efficacy of the DCB in Japanese routine clinical practice. The aim of this paper was to assess differences between the pre-marketing NP001 study and the PMS. Compared to the NP001 study, more complex lesions were treated in the PMS (type B2/C: 69.0% vs 20.4%, total occlusion: 11.2% vs 0%, p < 0.001, respectively) and target lesion was more frequently ISR related to drug-eluting stent (DES) (79.5% vs 39.4%, p < 0.001). Regarding clinical outcomes, the rate of target lesion revascularization (TLR) was higher in the PMS than in the NP001 study (TLR: 12.9% at 7 months and 17.6% at 12 months vs 2.8% at 6 months, p = 0.001, p < 0.001, respectively). Multivariable logistic regression analysis revealed that DES-ISR was a risk factor of TLR after DCB treatment for ISR (odds ratio: 5.77, 95% CI 1.75-18.95, p = 0.004). Among representative published trials using DCB for ISR, clinical outcomes are often worse in DES-ISR trials than those in bare metal stent-ISR trials. The rates of TLR in previous DES-ISR trials are similar to that in the current PMS (TLR at 12 months: 22.1% for ISAR-DESIRE 3, 15.3% for PEPCAD-DES, and 13.0% for RIBS IV). The effectiveness and safety of DCB for coronary ISR have been confirmed in the Japanese real-world survey. PMS would be useful to evaluate the safety and effectiveness of medical products throughout their total life cycles.

One-Year Clinical Outcome of Inspiron Stent in All-Comers Population (Analysis from 790 Consecutive Patients).

AIMS: The goal of this study was to evaluate the performance of the InspironTM coronary stent (Scitech Medical™, Goiás, Brazil). The InspironTM sirolimus-eluting stent uses an ultrathin L-605 cobalt-chromium alloy with a 75 µm strut thickness platform coated with an abluminal biodegradable polymer. The polymer is eliminated from the body through the tricarboxylic acid cycle in 6-9 months, releasing 80% of the drug within 30 days after its deployment. METHODS: It was a prospective, single-center registry. To represent clinical practice, all patients undergoing percutaneous coronary intervention were included in this registry. There were no exclusion criteria. Clinical follow-ups were performed at twelve months. The endpoints were the occurrence of all-cause death, definite stent thrombosis, and new revascularization. RESULTS: Between November 2017 and May 2019, 790 patients were included (1067 lesions). The mean age was 60.42 ± 14.94 years, and 74.7% presented with acute coronary syndrome. Diabetes mellitus was present in 43.9% of patients, and previous myocardial infarction and previous percutaneous coronary intervention were present in 17.9% and 11.3%, respectively. Angiographic success was achieved in 99.1%. The incidence of all-cause death was 11.5% (6.2% in-hospital and 5.3% in the follow-up) and definitive stent thrombosis was 0.2%. New revascularization was performed in only 5.8% (target lesion revascularization: 2.2%; progression of disease in another lesion: 3.6%). Based on the multivariate regression analysis, only chronic renal failure was an independent predictor of adverse events (OR: 3.3; 95% CI: 1.22-8.92). CONCLUSION: The result of this single-center registry demonstrates the safety and excellent performance of the InspironTM stent in daily clinical practice with a low rate of adverse cardiac events.

Histopathologic response after hydrophilic polyethylene glycol-coating stent and hydrophobic octadecylthiol-coating stent implantations in porcine coronary restenosis model.

Device-related problems of drug-eluting stents, including stent thrombosis related to antiproliferative drugs and polymers, can cause adverse events such as inflammation and neointimal hyperplasia. Stent surface modification, wherein the drug and polymer are not required, may overcome these problems. We developed hydrophilic polyethylene glycol (PEG)-coating and hydrophobic octadecylthiol (ODT)-coating stents without a drug and polymer and evaluated their histopathologic response in a porcine coronary restenosis model. PEG-coating stents (n = 12), bare-metal stents (BMS) (n = 12), and ODT-coating stents (n = 10) were implanted with oversizing in 34 porcine coronary arteries. Four weeks later, the histopathologic response, arterial injury, inflammation, and fibrin scores were analyzed. A p value < 0.05 was considered statistically significant. There were significant differences in the internal elastic lamina area, lumen area, neointimal area, percent area of stenosis, arterial injury score, inflammation score, and fibrin score among the groups. Compared to the BMS or ODT-coating stent group, the PEG-coating stent group had significantly increased internal elastic lamina and lumen area (all p < 0.001) and decreased neointimal area and percent area of stenosis (BMS: p = 0.03 and p < 0.001, respectively; ODT-coating: p = 0.013 and p < 0.001, respectively). Similarly, the PEG-coating group showed significantly lower inflammation and fibrin scores than the BMS or ODT-coating groups (BMS: p = 0.013 and p = 0.007, respectively; ODT-coating: p = 0.014 and p = 0.008, respectively). In conclusion, hydrophilic PEG-coating stent implantation was associated with lower inflammatory response, decreased fibrin deposition, and reduced neointimal hyperplasia than BMS or hydrophobic ODT-coating stent implantation in the porcine coronary restenosis model.

Effect of drug-coated balloon angioplasty on in-stent restenotic coronary lesions analyzed with optical coherence tomography and serial coronary artery angioscopy.

Drug-coated balloon angioplasty (DCBA) has been recognized for its utility in preventing in-stent re-restenosis (ISR); however, imaging of the neointima immediately after treatment and during follow-up has only been described in a few case reports. This study aimed to determine the efficacy and mechanism of the DCBA using imaging studies both immediately after the DCBA and during the follow-up period. We enrolled 15 consecutive patients who underwent DCBA for in-stent restenosis (ISR). The in-stent neointimal volume was evaluated using optical coherence tomography (OCT), and the in-stent yellow grade was assessed using coronary angioscopy (CAS) immediately after DCBA and during the median follow-up period of 9 (8-15) months. The neointimal volume was significantly reduced from 77.1 ± 36.2 mm3 at baseline to 60.2 ± 23.9 mm3 immediately after DCBA (p = 0.0012 vs. baseline) and to 46.7 ± 21.9 mm3 during the follow-up (p = 0.0002 vs. post DCBA). The yellow grade of the residual plaques at the ISR lesion, which indicated plaque vulnerability, was significantly decreased in the follow-up CAG (from baseline: 1.79 ± 1.03, during the follow-up: 0.76 ± 0.82; p < 0.0001). These data suggest that DCBA may inhibit neointimal formation and provide angioscopic intimal stabilization for ISR lesions.

Late lumen enlargement induced by drug coated balloon in the patient with PTFE-covered stent restenosis.

We report a case of percutaneous coronary intervention with drug coated balloon (DCB) for the in-stent restenosis of polytetrafluoroethylene-covered stent. One year follow-up angiography was excellent and in-stent lumen enlargement compared with the postprocedure and 6-months follow-up was demonstrated by optical coherent tomography. This case suggested the utility of DCB as a therapeutic option for covered-stent restenosis.

Can you score with balloons to enhance outcomes after drug coated balloon angioplasty? Insights from the Paris DCB Registry for in-stent restenosis.

OBJECTIVES: The objective of this study was to assess the 12-month clinical outcomes in patients with drug-eluting stent in-stent restenosis (DES-ISR) who were either pre-dilated with non-compliant balloons (NCBA) and with additional scoring balloons (NCBA + SBA) prior to drug coated balloon (DCB) angioplasty. METHODS: This monocentric, retrospective study included patients with DES-ISR who were routinely treated over a 2-year time span. Patients with stable angina and documented ischemia or selected forms of unstable angina due to a culprit DES-ISR lesion were analyzed. The primary endpoint was the clinically driven target-lesion revascularization (TLR) rate at 12 months. Secondary endpoints included post-interventional lumen gain and late lumen loss (LLL) at 6 months. RESULTS: The 12-month TLR rates in 124 patients who underwent either NCBA + SBA or NCBA only group were not different (17.3%, 9/52 vs 11.6%, 8/69, P = 0.371) and low as compared to other comparable studies. The use of SBA led to equally high post minimal lumen diameters (MLD) in both treatment arms (NCBA 2.21 ± 0.33 vs NCBA + SBA 2.18 ± 0.41, P = 0.868). We did not find a significant difference in late lumen loss (LLL) between both groups (0.50 ± 0.62 mm vs 0.40 ± 0.46 mm, P = 0.468). CONCLUSIONS: Scoring Balloon Angioplasty can safely and effectively prepare DES-ISR lesions to render them suitable for DCB angioplasty with acceptable TLR and MACE rates.

Analysis of the effect of paclitaxel-eluting stents and paclitaxel-eluting balloon in the treatment of in-stent restenosis.

To compare and analyze the effect and the safety of the paclitaxel-eluting stents and paclitaxel-eluting balloon in the treatment for in-stent rest enosis. 120 cases, who had been undergone percutaneous coronary intervention (PCI) in the Department of Cardiology of Henan Provincial People's Hospital from January 2012 to January 2014 were selected. All the patients were randomly treated with paclitaxel-eluting balloon or paclitaxel-eluting stents. The former were divided into different groups that named group A and the later group B. All the selected patients signed the informed consent on interventional therapy and be given anti-platelet drugs before operating. At the same time, they had routine examination, like chest X-ray, ultrasound, biochemical detection, Myocardial injury markers. (1) The two groups had no significant difference in the general information (P>0.05); (2) The success rate in the two groups reached 100% and (3) All the patients were visited in the 9th, 12th and 24th month to see if any of them was dead. The reexamination results in the 9th month showed that both drug-eluting balloon and drug-eluting stents were safe and effective in treating coronary artery in-stent restenosis. In addition, drug-eluting balloon was more effective than drug-eluting stents to prevent from the in-stent restenosis.

Comparing the efficacy and safety of two different drug-coated balloons in in-stent restenosis: Two-year clinical outcomes of the RESTORE ISR China randomized trial.

BACKGROUND: This head-to-head, multicenter, randomized trial investigated the safety and efficacy of Restore (Cardionovum, Bonn, Germany) drug-coated balloon (DCB) angioplasty in an Asian patient population with coronary drug-eluting stent in-stent restenosis (DES-ISR). METHODS: A total of 240 patients with coronary DES-ISR were treated with Restore DCB or with SeQuent® Please (Braun, Melsungen, Germany) DCB. This trial used nine-month in-segment late lumen loss (LL) as the primary endpoint. Secondary endpoints included two-year clinical event rates. RESULTS: Patient, lesion, and procedural characteristics in both treatment groups were similar. Nine-month in-segment LL was 0.38 ±â€¯0.50 mm with Restore vs. 0.35 ±â€¯0.47 mm with SeQuent® Please (p for non-inferiority = 0.02). The two-year follow-up rates were 95.8 % (115/120) in the Restore group and 94.2 % (113/120) in the SeQuent® Please group. Both groups had similar one- and two-year target lesion failure (TLF) rates (13.3 % vs. 12.6 %; p = 0.87 at one year, 14.8 % vs. 15.0 %; p = 1.0 at two years). Moreover, the all-cause mortality and myocardial infarction rates were 0 and 3.5 % (4/120) in the Restore group and 0.9 % (1/120) and 3.5 % (4/120) in the SeQuent® Please group, respectively. Additional analyzing of vessel quantitative flow ratio (QFR) did also show noninferior outcomes for one explicit treatment bunch. CONCLUSIONS: The two-year follow-up indicated sustained long-term clinical safety and efficacy for both devices on the basis of QFR value.

Long-term outcomes following drug-eluting balloons vs. thin-strut drug-eluting stents for treatment of recurrent restenosis in drug-eluting stents.

BACKGROUND: There is limited data on the optimal revascularization strategy in patients with recurrent in-stent restenosis (R-ISR). AIMS: To compare the long-term outcomes of patients treated with either a thin-strut drug-eluting stent (thin-DES) or a drug-eluting balloon (DEB) for R-ISR in a drug-eluting stent (DES). METHODS: A multicenter DEB-DRAGON registry was used to retrospectively identify patients with R-ISR who received either a thin-DES or a DEB. Propensity score matching was applied to adjust for baseline differences. The primary outcome was target lesion revascularization (TLR). RESULTS: Out of 311 patients (mean age, 67 years; 63% male) with R-ISR, 86 (27.7%) were treated with a thin-DES and 225 (72.3%) with a DEB. Median follow-up was 2.6 years. TLR occurred in 18 (20.9%) patients who received thin-DES and 61 (27.1%) patients treated with DEB (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.33-0.98; log-rank P = 0.04). The difference remained significant in a propensity score-matched cohort of 57 patients treated with thin-DES and 57 patients treated with a DEB (17.5 vs. 33.3%, respectively; HR, 0.38; 95% CI, 0.17-0.86; P = 0.01). The risks of device-oriented adverse cardiac events and all-cause mortality were similar after thin-DES or DEB in both unadjusted and propensity score-matched cohorts. In a multivariable Cox proportional hazard model, the treatment with a thin-DES was an independent predictor of a TLR-free survival (HR, 0.33; 95% CI 0.13-0.84; P = 0.02). CONCLUSIONS: In patients with R-ISR implantation of a thin-DES is associated with a lower risk of repeated revascularization compared with angioplasty with a DEB.

A multicentre, randomised controlled clinical study of drug-coated balloons for the treatment of coronary in-stent restenosis.

AIMS: Treatment of in-stent restenosis of coronary stents is challenging. The use of drug-coated balloons (DCB) is a promising technique to treat in-stent restenosis without adding another metal layer. The aim of the AGENT ISR randomised trial is to evaluate angiographic and clinical outcomes in patients with ISR of a previously treated lesion who were treated with either a DCB with a new coating formulation (Agent) or a standard DCB (SeQuent Please). METHODS AND RESULTS: AGENT ISR is a multicentre, randomised, open-label, non-inferiority study comparing the Agent and SeQuent Please DCB. A total of 125 patients (mean age ~68 years, 18% female) with in-stent restenosis of a previously treated lesion <28 mm in length were randomised at 11 sites in Europe to Agent (n=65) or SeQuent Please (n=60). The primary endpoint, six-month in-stent late lumen loss, in the Agent group (0.397±0.43 mm [n=51]) was non-inferior to that of the SeQuent Please group (0.393±0.536 mm [n=49]), as the two-sided upper 95% confidence boundary for the difference between groups was less than the pre-specified non-inferiority margin of 0.20 (difference 0.004, 95% CI [-0.189, 0.196]; pnon-inferiority=0.046). At one year, mortality was 3.1% in Agent and 1.7% in SeQuent Please patients (p>0.99), target lesion revascularisation 7.7% versus 10.0% (p=0.89), and stent thrombosis 0% versus 3.3% (p=0.44). Similar improvements in quality of life were seen in the two groups. CONCLUSIONS: In this head-to-head comparison of two DCB, Agent proved to be non-inferior to SeQuent Please for in-stent late lumen loss at six months. CLINICAL TRIALS REGISTRATION: NCT02151812 (http://clinicaltrials.gov/).

The short-term effect on restenosis and thrombosis of a cobalt-chromium stent eluting two drugs in a porcine coronary artery model.

The aim of this article was to study the effect of dual drug-eluting stent (DES) on both restenosis and thrombosis in a porcine coronary artery model. This study reports on the use of two drugs coated on the stent to simultaneously minimize both restenosis and thrombosis. The DES was prepared by spray coating a bare metal stent with a biodegradable polymer loaded with sirolimus and triflusal, to treat against restenosis and thrombosis, respectively. The two-layered dual drug-coated stent was characterized in vitro for surface properties before and after expansion, as well as for possible delamination by cross-sectioning the stent in vitro. In vivo animal studies (in a pig model) were then performed for acute thrombosis, inflammation, and restenosis. The results show a significant reduction in restenosis with a stent coated with both drugs compared with the controls (a bare metal stent, a sirolimus-coated, and a pure polymer-coated stent). The reduction in restenosis with a sirolimus/triflusal-eluting stent is associated with an inhibition of inflammation and thrombus formation, suggesting that such dual DES have a role to play for the treatment of coronary artery diseases.

Long-Term Follow-Up After Treatment of Drug-Eluting Stent Restenosis and De Novo Lesions Using SeQuent Please Paclitaxel-Coated Balloons.

Managing patients with in-stent restenosis (ISR) remains an important clinical challenge. In particular, large, randomized trials assessing the effect of drug-eluting balloons (DEB) in patients with de novo lesions are warranted. We investigated the effect of DEB on procedural complications, target lesion revascularization (TLR), and major adverse cardiac and cerebrovascular events in patients with drug-eluting stent ISR and de novo lesions. The clinical profiles of 238 consecutive patients treated for coronary ISR (n = 174) and de novo lesions (n = 64) using SeQuent Please paclitaxel-coated balloon were analyzed. Study end points were major adverse cardiac events (MACEs). At 1-year follow-up, TLR and MACEs occurred with acceptably low rates (5.0% and 6.3%, respectively). At 2.00 (0.74) years of follow-up, there was a significant difference in the rates of TLR between the ISR and the de novo lesions groups (14.4% [ISR] vs 3.1% [de novo], P = .028), and the occurrence of MACEs distinctly increased in the ISR group compared to the de novo lesions group (21.8% vs 6.2%, P = .009). The long-term outcomes of the ISR group were inferior to those of the de novo group (TLR, log-rank P = .019; MACEs, log-rank P = .010). Drug-eluting balloon for ISR and de novo lesions of small coronary vessels is effective and safe.

Treatment of Drug-Eluting Stent In-Stent Restenosis With Drug-Eluting Balloons: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the efficacy of drug-coated balloon (DEB) for the treatment of drug-eluting stent (DES) in-stent restenosis (ISR). METHODS: A comprehensive literature search was performed. The primary outcome was the composite of death, myocardial infarction (MI), and target-lesion revascularization (TLR) at longest available follow-up (range, 12-36 months). Outcomes for DEB vs balloon angioplasty (BA) and DEB vs DES were analyzed separately using a random-effect Mantel-Haenszel model, as per an a priori protocol. RESULTS: The study cohort comprised 1526 patients (746 DEB, 537 DES, 243 BA). DEB was associated with lower composite outcome compared with BA alone (19% vs 47%; risk ratio [RR], 0.31; 95% confidence interval [CI], 0.11-0.84; P=.02), driven primarily by lower TLR (17% vs 34%; RR, 0.66; 95% CI, 0.46-0.95; P=.03), with no difference in death or MI. There was no difference in the composite outcome between DEB and DES (20% vs 17%; RR, 1.2; 95% CI, 0.82-1.74; P=.35); DEB was associated with higher TLR (17.4% vs 11.3%; RR, 1.48; 95% CI, 1.08-2.03; P=.01), but lower all-cause mortality (2.2% vs 5.7%; RR, 0.43; 95% CI, 0.22-0.82; P=.01), with no difference in MI or stent thrombosis. CONCLUSIONS: DEB was associated with a lower TLR rate than BA alone, but associated with a higher TLR rate than implantation of another DES. However, additional DES use was associated with an increase in mortality, a finding that requires further investigation.

A Randomized Comparison of Paclitaxel-Eluting Balloon Versus Everolimus-Eluting Stent for the Treatment of Any In-Stent Restenosis: The DARE Trial.

OBJECTIVES: The authors sought to evaluate the relative performance of a drug-eluting balloon (DEB) and a drug-eluting stent (DES) in patients with any (bare-metal or drug-eluting stent) in-stent restenosis (ISR). BACKGROUND: The treatment of ISR remains challenging in contemporary clinical practice. METHODS: In a multicenter randomized noninferiority trial, patients with any ISR were randomly allocated in a 1:1 fashion to treatment with a DEB (SeQuent Please paclitaxel-eluting balloon, B. Braun Melsungen, Melsungen, Germany), or a DES (XIENCE everolimus-eluting stent, Abbott Vascular, Santa Clara, California). The primary endpoint was noninferiority in terms of in-segment minimal lumen diameter (MLD) at 6-month angiographic follow-up. Secondary endpoints included angiographic parameters at 6 months and clinical follow-up up to 12 months. RESULTS: A total of 278 patients, of whom 56% had DES-ISR, were randomized at 8 sites to treatment with DEB (n = 141) or DES (n = 137). As compared with DEB, DES was associated with larger MLD and lower % stenosis immediately post-procedure (1.84 ± 0.46 vs. 1.72 ± 0.35; p = 0.018; and 26 ± 10% vs. 30 ± 10%; p = 0.03). Angiographic follow up was completed at 196 ± 53 days in 79% of patients. With respect to the primary endpoint of in-segment MLD at 6 months, DEB was noninferior to DES (DEB 1.71 ± 0.51 mm vs. DES 1.74 ± 0.61 mm; p for noninferiority <0.0001). Target vessel revascularization at 12-month follow-up was similar in both groups (DES 7.1% vs. DEB 8.8%; p = 0.65). CONCLUSIONS: In patients with ISR, treatment with DEB was noninferior compared with DES in terms of 6-month MLD. There were no differences in clinical endpoints, including target vessel revascularization up to 12 months. Therefore, use of a DEB is an attractive treatment option for in-stent restenosis, withholding the need for additional stent implantation.

Preclinical evaluation of a paclitaxel-incorporated nanoparticle-coated balloon in rabbit and porcine models.

BACKGROUND: The main drawback of current available drug coated balloons (DCB) is that a certain percentage of the coated drug is lost in the bloodstream during its delivery to the target lesion. We integrated the nanoparticle-mediated drug delivery technology and polydimethylsiloxane (PDMS) as a new excipient to facilitate an efficient drug delivery and uptake by endothelial cells. The present study aimed to evaluate the efficacy of the new DCB. METHOD AND RESULTS: The novel DCB were coated with 5.6mg of paclitaxel-incorporated nanoparticles using PDMS. The efficacy of the new DCB was examined in rabbit iliac stent model (n=12) and in the swine in-stent restenosis model (n=8) by quantitative coronary angiography (QCA) and optical coherence tomography (OCT). At 28days follow-up in the swine in-stent restenosis model, the area stenosis was significantly lower in DCB group as compared with that of the control group in OCT analysis (0.31±0.05 vs 0.49±0.06, p=0.04) though there was no significant differences observed in the rabbit iliac stent model in QCA and OCT analysis. CONCLUSION: The study results indicated that the paclitaxel-incorporated nanoparticle-coated balloon using PDMS has an inhibitory effect for the proliferation of smooth muscle cell in a swine coronary in-stent restenosis model.

Very late in-stent restenosis in a bare metal stent.

Restenosis after coronary artery stenting is a common phenomenon and represents a topic of great interest. Although a great volume of research is referring to restenosis, still many issues are not fully understood by the cardiological community. Here we present a case of very late restenosis, after a bare metal stent implantation.

Coronary artery aneurysm formation following implantation of a bioresorbable vascular scaffold for in-stent restenosis.

Coronary artery aneurysm (CAA) formation is a rare complication of coronary intervention that may develop after implantation of bare-metal or drug-eluting stents. The etiology of this entity appears to be multifactorial and its prognosis is poorly understood, but it has been associated with an increased risk of stent thrombosis. To date few cases of CAAs related to bioresorbable vascular scaffold (BVS) implantation have been reported, and the development of CAA after BVS implantation for the treatment of in-stent restenosis (ISR) has not been previously described. Here we present two cases of CAA formation after BVS, which represent the first demonstration of CAA formation after the use of BVS for ISR.

Comparable vascular response of a new generation sirolimus eluting stents when compared to fluoropolymer everolimus eluting stents in the porcine coronary restenosis model.

BACKGROUND: Novel sirolimus eluting stents (SES) have shown non-inferior clinical outcomes when compared to everolimus eluting stents (EES), however only limited preclinical data have been published. Therefore, we evaluate vascular response of a new generation biodegradable polymer SES (BP-SES: Alex Plus, Balton) and fluoropolymer EES (EES: Xience Pro, Abbott) in the porcine coronary restenosis model. METHODS: A total of 40 stents were implanted with 120% overstretch in coronaries of 17 domestic swine: 16 BP-SES, 16 EES and 8 bare metal controls (BMS). Following 28 and 90 days, coronary angiography and optical coherence tomography (OCT) was performed, animals sacrificed and stented segments harvested for pathological evaluation. RESULTS: At 28 days neointimal thickness in OCT was lowest in the BP-SES when compared to EES and BMS (0.18 ± 0.1 vs. 0.39 ± 0.1 vs. 0.34 ± 0.2 mm, respectively; p = 0.04). There was no difference in the proportion of malapposed or uncovered struts, although protruding covered struts were more common in BP-SES (14.8 ± 10% vs. 4.1 ± 4% vs. 3.7 ± 6%; p = 0.03). In pathology, the lowest neointimal thickness was confirmed in BP-SES (p < 0.05). The inflammation score was significantly lower in BP-SES and EES when compared to BMS (0.24 ± 0.1 vs. 0.4 ± 0.1 vs. 0.77 ± 0.4; p < 0.01) whilst EES and BP-SES had higher fibrin scores than BMS (1.2 ± 0.4 vs. 1.3 ± 0.3 vs. 0.17 ± 0.2; p < 0.01). At 90 days neointimal coverage and thickness in OCT was comparable between groups and healing in histopathology was complete. CONCLUSIONS: New generation, BP-SES show similar vascular healing and biocompatibility profile with marginally higher degree of restenosis inhibition, when compared to fluoropolymer EES in the porcine coronary restenosis model.