Stent Apposition Research Articles

Importance of optimal rewiring guided by 3-dimensional optical frequency domain imaging during double-kissing culotte stenting demonstrated through a novel bench model

The usefulness of optical frequency domain imaging (OFDI) guidance on two-stenting at left main bifurcation has not been evaluated. Here, we used a novel bench model to investigate whether pre-defined optimal rewiring with OFDI-guidance decreases acute incomplete stent apposition (ISA) at the left main bifurcation segment. A novel bench simulation system was developed to simulate the foreshortening and overlapping of daughter vessels as well as left main bifurcation motion under fluoroscopy. Double-kissing (DK) culotte stenting was performed using the novel bench model under fluoroscopy with or without OFDI-guidance. In the OFDI-guidance group, if the guidewire did not pass through the pre-defined optimal cell according to the 3-dimensional OFDI, additional attempts of rewiring into the jailed side branch were performed. The success rate of optimal jailed side branch rewiring after implantation of the first and second stent under OFDI-guidance was significantly higher than that under only angio-guidance. After completion of the DK-culotte stenting, the incidence and volume of ISA at the bifurcation segment in the OFDI-guidance group was significantly lower than that in the angio-guidance group. Online 3-dimensional OFDI-guided DK-culotte stenting according to a pre-defined optimal rewiring point might be superior to only angio-guided rewiring for reducing ISA at the bifurcation.

Three-dimensional reconstruction imaging by C-arm computed tomography accurately visualizes in-stent neointimal formation in patients with stent-assisted coil embolization.

Stent apposition to the vessel wall and in-stent neointimal formation after stent-assisted coil embolization for intracranial aneurysm are important factors associated with postoperative thromboembolic complications. No assessment methods have been established to depict 3-dimensional (3D) all-round in-stent neointimal formation. To demonstrate the superiority of Dyna-3D imaging assessment as a modality for all-round ISNF in comparison with conventional two-dimensional digital subtraction angiography (2D-DSA). Consecutive patients who underwent braided stent-assisted coil embolization for unruptured aneurysm between November 2016 and September 2021 were enrolled. Radiological assessments for stent apposition to the parent vessel after stent deployment and in-stent neointimal formation after 3 months were obtained. Dyna-3D was reconstructed by overlapping a plain image showing stent struts with a rotational DSA image showing the vessel lumen. Reconstructed Dyna-3D images can be rotated to any angle on the screen to evaluate to stent apposition around the vessel and in-stent neointimal formation in 3D, for comparison with 2D-DSA evaluations. Among the 73 patients enrolled, 70 patients (96%) showed complete stent wall apposition on Dyna-3D. Higher intra-rater agreement was confirmed on assessment of in-stent neointimal formation with Dyna-3D (Cohen's κ = 0.811) than with conventional 2D-DSA (Cohen's κ = 0.517). in-stent neointimal formation could not be confirmed on conventional imaging in 9 cases (16%) and on Dyna-3D in 2 cases (3%). The number of in-stent neointimal formations rated as stent wire completely outside the endothelial line was significantly higher with Dyna-3D than with 2D-DSA (p = 0.0001). All-round 3D evaluation by Dyna-3D imaging appears useful for confirming in-stent neointimal formation after braided stent deployment in patients after stent-assisted coil embolization.

Incidence, risk factors, and clinical sequelae of incomplete stent apposition after sirolimus-eluting stent.

Incomplete stent apposition has been documented after sirolimus-eluting stent implantation. However, its clinical sequelae remain controversial. To identify the incidence and its clinical consequences of ISA, IVUS was performed on 78 patients. In spite of well apposition immediately after the deployment, late stent malapposition occurred after 6-months follow-up. A total of 7 patients who received SES showed ISA. There were no significant differences in IVUS measurements between patients with or without ISA. However, there was an increase in external elastic membrane area in ISA group than non-ISA group (19.69 ± 3.50 vs. 15.05 ± 2.56 mm2, P<0.05). There were positive clinical events for ISA cases at 6-months clinical follow-up. Univariate and multivariable analyses indicated that hs-CRP, miR-21, and MMP-2 were risk factor for ISA. ISA was observed in 9% of patients after SES implantation, which was related to vessel positive remodeling. The incidence of MACEs in patients with ISA was higher than those without ISA. However, careful long-term follow-up remains to be clarified.

Drug-Coated Balloon in Primary Percutaneous Coronary Intervention.

According to the latest coronary interventional guidelines, a drug-eluting stent is the recommended reperfusion therapy in primary percutaneous coronary intervention (pPCI). However, deficiencies and defects, such as in-stent restenosis (ISR), incomplete stent apposition, stent thrombosis, reinfarction after stent implantation, long-term dual antiplatelet drug use, and adverse reactions of metal implants, plague clinicians and patients. Drug-coated balloon (DCB), which delivers antiproliferative agents into the vessel wall without stent implantation and leaves no implants behind after the procedure, is a novel option for percutaneous coronary intervention and has proven to be a promising strategy in cases of ISR, small vessel coronary artery disease, and bifurcation lesions. However, most of the available experience has been gained in elective percutaneous coronary intervention, and experience in pPCI is lacking. The current evidence for the use of DCB-only in pPCI was discussed and analyzed in this review.

P39 MANAGEMENT OF A CASE OF LAST REMAINING PATENT VESSEL

Abstract A 72–year–old hypertensive, dyslipidemic and smoker (20 cig/day) gentleman was admitted to the emergency department for pulmonary edema. Past medical history included COPD, anterior MI treated with PCI and stenting of proximal LAD 5 years back, recent TIA. He was admitted to cardiac intensive care unit and treated with CPAP, IV furosemide and norepinephrine. Echocardiogram showed severe ventricular dysfunction (LVEF 20%) and severe functional mitral regurgitation; lab tests pointed out mild troponin elevation (50 ng/L) and high levels of BNP (1300 pg/mL). After stabilization, he underwent coronary angiography: in–stent CTO of LAD, critical stenosis of distal LM and ostio–proximal LCX (last remaining patent vessel, LRPV); hypoplastic RCA. At the end of angiography, new episode of pulmonary edema that required treatment with inotropes, CPAP and diuretics. Considering hemodynamic instability and high surgical risk (combined STS 37%), the Heart Team decided to proceed to PCI with mechanical circulatory support with Impella CP. From left radial access we achieved advancement of JR4 guiding catheter with guide extension in right common iliac artery. We performed angiography and then put a coronary guidewire in superficial femoral artery to facilitate right femoral access (angio–guided). From this femoral access we implanted Impella CP device. From left radial access we performed PCI: cannulation with JL 3 guiding catheter, wiring with Sion Blue ES guidewire, pre–dilatation with NC balloons until 3.0 mm diameter, stenting of LM–LCX with 1 DES 4.0/32 mm, post–dilatation with NC balloons (4.5 and 5.0 mm diameter). Good angiographic result; IVUS examination revealed good expansion and apposition of stent. Femoral access was closed with 2 Perclose Proglide. Patient was then monitored in cardiac intensive care unit, with clinical improvement and without complications. 10 days after PCI the patient, asymptomatic, was discharged. The echocardiogram displayed betterment of contractile function (LVEF 28%) and of mitral regurgitation (now moderate). At 4–month follow–up visit, patient is paucisymptomatic (NYHA class II), without angina episodes, with good quality of life in guideline–directed optimal medical therapy. Critical disease of LRPV is a severe condition, with unpredictable evolution and poor prognosis. PCI of LRPV in HFrEF patients is an high–risk PCI scenario in which mechanical circulatory support with Impella can prove to be essential.

The Degree of Stent Apposition Measured by Stent Enhancement at the Level of the Side Branch as a Novel Predictor of Procedural Success in Left Main PCI.

Stent enhancement techniques allow adequate visualization of stent deformation or incomplete stent expansion at the ostium of the side branch. Measuring the stent enhancement side branch length (SESBL) could reflect procedural success in terms of optimal stent expansion and apposition with better long-term outcomes. A longer SESBL may reflect a better stent apposition at the polygon of confluence and at the side branch (SB) ostium. We evaluated 162 patients receiving the left main (LM) provisional one-stent technique and measured the SESBL, dividing them into two groups: SESBL≤ 2.0 mm and SESBL > 2.0 mm. The mean SESBL was 2.0 ± 1.2 mm. More than half of the bifurcations had both main and side branch lesions (Medina 1-1-1) (84 patients, 51.9%) and the length of the SB disease was 5.2 ±1.8 mm. Kissing balloon inflation (KBI) was performed in 49 patients (30.2%). During follow-up (12 months), there was a significantly higher rate of cardiac death in the SESBL ≤ 2.0 mm group (p = 0.02) but no significant difference in all major adverse cardiovascular events (MACEs) (p = 0.7). KBI did not influence the outcomes (p = 0.3). Suboptimal SESBL is positively correlated with worse outcomes and SB compromise. This novel sign could aid the LM operator to assess the level of stent expansion at the ostium of the SB in the absence of intracoronary imaging.

Stent expansion evaluated by optical coherence tomography and subsequent outcomes

Regarding stent expansion indices, previous optical coherence tomography (OCT) studies have shown minimal stent area (MSA) to be most predictive of adverse events. We sought to evaluate the impact of various stent expansion and apposition indices by post-stent OCT on clinical outcomes and find OCT-defined optimal stent implantation criteria. A total of 1071 patients with 1123 native coronary artery lesions treated with new-generation drug-eluting stents with OCT guidance and final post-stent OCT analysis were included. Several stent expansion indices (MSA, MSA/average reference lumen area, MSA/distal reference lumen area, mean stent expansion, and stent expansion by linear model [stent volume/adaptive reference lumen volume]) were evaluated for their association with device-oriented clinical endpoints (DoCE) including cardiac death, target vessel-related myocardial infarction (MI) or stent thrombosis, and target lesion revascularization. MSA was negatively correlated with the risk of DoCE (hazard ratio [HR] 0.80 [0.68‒0.94]). However, stent expansion by linear model representing the overall volumetric stent expansion was associated with greater risk of DoCE (HR 1.02 [1.00‒1.04]). As categorical criteria, MSA < 5.0 mm2 (HR 3.90 [1.99‒7.65]), MSA/distal reference lumen area < 90% (HR 2.16 [1.12‒4.19]), and stent expansion by linear model ≥ 65.0% (HR 1.95 [1.03‒3.89]) were independently associated with DoCE. This OCT study highlights the importance of sufficient stent expansion to achieve adequate, absolute, and relative MSA criteria for improving clinical outcome. It also emphasises that overall volumetric excessive stent expansion may have detrimental effects.

Abstract Number ‐ 130: Comparison of the Stents Length by Virtual Stent Simulation with the Actual Stent Length

Introduction The selection of the size of a braided stent, such as the flow diverter stent, currently depends on the surgeon’s experience. However, the suitable selection is difficult even for experienced surgeons due to shortening during the deployment. The unsuitable choice of the stent size may result in poor stent apposition or dislodgement of the stent, which may lead to inadequate treatment and increase the risk of complications. To overcome the selection problem, we developed a virtual stent simulation that virtually reproduces the stent geometry preoperatively. However, the lengths of the deployed stents in the virtual stent simulation have not been compared with those in the actual stents. In this study, we evaluated the error between the length of the virtual stent and the actual stent to investigate the clinical usefulness of the virtual stent simulation. Methods We identified 48 internal carotid artery cerebral aneurysms treated with a single flow diverter stent (PipelineTM) between October 2016 and March 2022. The vessel geometries were reconstructed from the preoperative angiographic images, and the virtual stent geometries were reproduced using virtual stent simulation with our in‐house code. The actual stent geometries were reconstructed from the postoperative angiographic images and overlaid on the preoperative vessel geometries using affine transformation. The lengths of the virtual and actual stents were measured, respectively. The differences between the lengths of the virtual and actual stents were calculated by subtracting the actual stent length from the virtual stent length. The errors between the virtual and actual stents were estimated to validate the virtual stent simulation. Results The average maximum diameter in the 48 aneurysms was 16.4±5.91 mm. The average difference in length between the virtual stents and the actual stents was +1.70 ± 4.01 mm, with the average error based on virtual stent length of +3.24 ± 11.3%. The virtual stents of 16 aneurysms were shorter than the actual stents, and the average difference in length was ‐2.97 ± 1.82 mm. On the other hand, the virtual stents of the other 32 aneurysms were longer than the actual stents, with the average difference in length of +4.04 ± 2.47 mm. One possible cause of these differences is that the actual stent may slightly change the geometry of the parent vessel due to the restoring force of the stent. Another reason is that the actual length of the stent may change slightly as the surgeon pushes and pulls the catheter during the procedure. Conclusions Comparing the lengths of virtual and actual stents, it was confirmed that there was some error between the stent length reproduced by the virtual stent simulation and the actual stent length. In particular, the virtual stents tend to be slightly longer than the actual stents. Although our virtual stent may be useful for identifying the appropriate size, it is necessary to investigate the causes of such errors and to realize virtual stent simulations with fewer errors.

Complex, high-risk, and indicated percutaneous coronary angioplasty in essentially calcified stented coronary lesions using excimer laser coronary atherectomy with contrast mix injection.

Complex, coronary stenosis remains a technical challenge that may be responsible for in-stent restenosis and vessel thrombosis. Here we investigated the efficacy and safety of excimer laser coronary atherectomy (ELCA) with contrast mix injection for improving vessel wall stent apposition in undilatable, mostly calcified lesions. To assess ELCA with contrast mix injection in complex, stented, calcified coronary lesions. This prospective single-center observational study enrolled 52 consecutive patients (73 lesions), with suboptimal stents implanted in de novo lesions and lesions requiring in-stent restenosis (ISR) due to stent underexpansion using all available means to achieve an optimal result. Patients presenting with ST-segment elevation myocardial infarction were excluded. All patients underwent coronary angiography 6 months after ELCA with intravascular ultrasound or optical coherence tomography study. We used contrast media mixed with saline (25-75%) to supply maximum laser energy output when a standard approach was unsuccessful. Procedural success was defined as relative stent expansion of > 80% minimal stent area (MSA) divided by average reference lumen area. Procedural success was achieved in all cases. The cross-sectional area measured in treated segment improved significantly from 2.9 (0.72) mm2 to 7.3 (0.79) mm2 after ELCA. The in-hospital device-oriented major adverse cardiac event (DOCE) rate was 9.6%. No vessel perforation occurred during ELCA. After 6 months, the DOCE rate was 13.4%, while the rate of target lesion revascularization (TLR) was 8.2%. This registry confirms the efficacy and safety of ELCA with contrast mix injection as a possible approach for stent expansion/ISR in failed PCI.

A novel hybrid strategy of drug coated balloon and stent for coronary bifurcation lesions

Background. Provisional side branch (SB) stenting strategy is the default approach for the majority of bifurcation lesions, but outcomes of SB is suboptimal. Though drug coated balloon (DCB) improving SB outcomes attracts an increasing attention, sequence of DCB hasn’t yet been determined. We presented a novel hybrid strategy of DCB and stent for bifurcation lesions. Methods. With lesion preparation, DCB was persistently inflated in SB kissing with main branch (MB) stent deployment and balloon post-dilation of the bifurcation core. Proximal optimization technique was performed strictly not exceeding the bifurcation. Procedural and clinical adverse events were evaluated. Canadian Cardiovascular Society (CCS) angina classification was assessed at baseline and clinical follow-up. Results. Fourteen patients undergoing the hybrid technique from August 2020 to July 2021 were enrolled. The technique was successfully performed in all patients without rewiring or SB compromise. Minimal lumen diameter of SB increased from 0.60 ± 0.40 mm to 2.1 ± 0.2 mm while the percent stenosis decreased from 72.4 ± 17.9% to 19.6 ± 4.7%. In addition, intravascular ultrasound indicated comparable stent symmetry index and incomplete stent apposition between proximal and distal segments of stent. No further intervention was performed, and mean fractional flow reserve of SB (n = 12) was 0.88 ± 0.05. No major adverse cardiac events was noted in hospital and 12-month follow up. The mean CCS angina score was reduced by 84% (2.2 vs 0.4, p < .001). Conclusion. The hybrid strategy facilitates treatment of DCB and stent for bifurcation lesions, which appears to be feasible and acceptable in a short-term follow-up.

Enterprise 2 Stent-Assisted Embolization of Paraclinoid Aneurysms: A Single Center Preliminary Study.

Enterprise stent has been widely used for assisted embolization in wide-necked aneurysms while delayed ischemia or thromboembolic complications for its incomplete stent apposition. The purpose of this study was to summarize and analyze the clinical experience of using Enterprise 2 (EP2) stent-assisted embolization in the treatment of paraclinoid aneurysms. From January 2019 to December 2020, the clinical and imaging data of 98 patients with paraclinoid aneurysms treated with EP2 stent-assisted embolization were enrolled retrospectively. Preliminary experience and follow-up outcomes of EP2 stent-assisted embolization of paraclinoid aneurysms were assessed by using the Raymond grade and modified Rankin Scale. Of the 98 aneurysms, all stents were released satisfactorily. The immediate postprocedural angiography revealed a complete occlusion of the aneurysms with 77.55% of the (76/98) patients, and the last follow-up angiograms showed complete occlusion with 83.67% of the (82/98) patients. The average aneurysm size was (4.11 ± 1.25) mm, the aneurysm diameter was (4.41 ± 1.37) mm, the vessel radius was (3.87 ± 0.32) mm, the diameter at the distal of stent was (3.23 ± 0.21) mm, and the proximal was (4.18 ± 0.23) mm. Among the 98 aneurysms, 13 cases had incomplete stent apposition, 3 cases had intraoperative knotting, and the stents were improved post adjusted; 2 cases had vasospasm and 1 case had stenosis during operation, the symptoms were improved after symptomatic treatment. The result demonstrated that stent length and inner bending radius of parent artery were the pivotal factors affecting incomplete stent apposition (P < 0.01). The EP2 stent for the treatment of paraclinoid aneurysms is safe and effective, however, the length of the stent and the inner bending radius of parent artery are important factors affecting incomplete stent apposition.

Impact of intravascular ultrasound-incomplete stent apposition on stent failure.

This study aimed to investigate the relationship between immediate incomplete stent apposition (ISA) detected by intravascular ultrasound (IVUS) and midterm stent failure. Stent failure is one of serious clinical events related to percutaneous coronary intervention (PCI). The previous studies using optical coherence tomography showed that ISA could be associated with stent thrombosis. However, the association between immediate ISA detected by IVUS and stent failure has not been fully investigated. We included 396 lesions that underwent elective PCI, and divided those into the appropriate stent apposition (ASA) group (n = 290) and the ISA group (n = 106). The primary endpoint was stent failure, which was defined as a composite of ischemia-driven target lesion revascularization and stent thrombosis. We compared clinical and lesion characteristics between the two groups, and performed a multivariate COX hazard analysis to investigate the association between immediate ISA and stent failure. The median follow-up duration was 1296 days. The Kaplan-Meier curves revealed the higher incidence of stent failure in the ISA group than in the ASA group (p < 0.001). The multivariate stepwise COX hazard analysis showed that immediate ISA (hazard ratio 4.97, 95% confidence interval 1.31-18.82, p = 0.018) was significantly associated with stent failure. When we set the cut-off value of the immediate ISA distance as 0.25 mm, the distance ≥ 0.25 mm had 68.8% sensitivity and 85.0% specificity to predict stent failure. Immediate ISA detected by IVUS was associated with midterm stent failure. We should pay attention to reduce immediate ISA for improving the midterm outcomes.

Evaluation of the apposition in unruptured aneurysms treated with flow diverters by optical coherence tomography: Preliminary clinical experience.

The risk of perioperative stroke and the rate of occlusion of long-term aneurysms in the treatment of unruptured aneurysms with flow diverters (FDs) are affected by stent apposition. Optical coherence tomography (OCT) may be an optional technique in evaluating apposition. To explore the feasibility of the OCT imaging technique in evaluating stent apposition in the clinical application of the FD for unruptured aneurysms. OCT and Vaso CT were used in patients with indications for surgery to treat unruptured aneurysms with the FDs, to evaluate the apposition of the FDs after fully released, and to analyze OCT images for FDs apposition and compare with corresponding Vaso CT images. A total of four patients were enrolled, and OCT found malapposition after FDs placement in all four patients, and the maximum gap between the stent and vascular wall ranged from 0.68 to 1.95 mm and the length of malapposition ranged from 1.80 to 7.40 mm. However, Vaso CT found malapposition only in two of the four patients and missed malapposition near aneurysm in all three patients treated by the FD combined with coiling and could not accurately evaluate the maximum gap and the length of the malapposition. The optical coherence tomography technique is a possible approach to evaluate apposition after the treatment of unruptured aneurysms by the FDs.

Effects of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms

BackgroundThis study analyzed the safety and efficacy of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms by examining stent-vessel apposition, operative complications, embolization outcomes, and clinical outcomes.MethodsWe retrospectively reviewed the medical records of patients with wide-necked intracranial aneurysms who underwent Enterprise 2 stent-assisted coiling in our hospital from November 2018 to October 2019. Intraoperative VasoCT was performed immediately after stent release in a continuous cohort of patients to observe stent-vessel apposition. Patient demographic, clinical, and imaging data were recorded and analyzed.ResultsA total of 106 wide-necked aneurysms in 106 patients were treated. Stent release was successful in all patients. Twenty-one patients were enrolled consecutively for VasoCT scanning, and incomplete stent apposition was observed in 5 (23.8%). Perioperative complications occurred in 10 patients (9.4%): cerebral infarction in 6, intraoperative coil prolapse in 1, puncture site pseudoaneurysm in 1, deep vein thrombosis at multiple sites in 1, and transient brainstem mass effect in 1. Among the 95 aneurysms with angiographic follow-up, embolization was satisfactory (Raymond–Roy classifications I and II) in 89 (93.7%). Hyperlipidemia was an independent risk factor for incomplete aneurysm occlusion. At the last clinical follow-up, seven patients had a poor clinical outcome (modified Rankin Scale score ≥ 3). Independent risk factors for poor outcomes were preoperative subarachnoid hemorrhage at presentation and cerebral infarction.ConclusionEnterprise 2 stent-assisted coiling for treatment of wide-necked intracranial aneurysms showed good safety and efficacy; however, incomplete stent apposition can still occur in vessels with a large curvature. Preoperative subarachnoid hemorrhage at presentation and cerebral infarction are the main reasons for poor clinical outcomes after stent-assisted coil embolization.

Impact of Reference Mismatch on Procedure Outcomes of Percutaneous Coronary Intervention.

A significant mismatch between proximal and distal reference lumen diameters of the target lesion may pose challenges during percutaneous coronary intervention (PCI) and therefore influence the outcomes. We investigated total 1706 lesions underwent IVUS guided percutaneous coronary intervention, that were divided into 2 groups, including 411 lesions in Mismatch group and 1295 lesions in Non-Mismatch group. After propensity score matching, 397 lesions in each group were selected for final data set. The analysis showed that Mismatch group PCI required more frequently use of post-stenting optimization (79.6% vs 53.9%, P < .001) using higher max pressure (19.5 ± 3.9 vs 16.7 ± 3.7atm, P < .001). Besides, Mismatch group also encountered more PCI major complications (7.8% vs 4.0%, P = .024) and lower procedure success rate (91.4% vs 95.5%, P = .022). On final angiogram, Mismatch group had smaller minimum lumen diameter (2.62 ± .45 vs 2.90 ± .57mm, P < .001) and lower angiographic success rate (93.2% vs 96.7%, P = .023). On final IVUS, Mismatch group had higher rate of incomplete stent apposition and stent edge dissection (6.3% vs 3.0%, P = .029 and 2.5% vs .5%, P = .021, respectively). In conclusion, reference mismatch posed significant challenging during PCI that led to unfavorable procedural outcomes. These impacts may translate into long-term clinical implications that need to be addressed in future studies.

Clinical Outcomes of Different Calcified Culprit Plaques in Patients with Acute Coronary Syndrome.

Background: Previous studies have found that coronary artery calcification is closely associated with the occurrence of major adverse cardiac events (MACE). This study aimed to investigate the characteristics and clinical outcomes of different calcified plaques in patients with acute coronary syndrome (ACS) by using optical coherence tomography (OCT). Methods: 258 ACS patients with calcified culprit plaques who underwent OCT-guided stent implantation were enrolled. They were divided into three subtypes based on the calcified plaque morphology, including eruptive calcified nodules, calcified protrusion, and superficial calcific sheet. Results: Compared with superficial calcific sheet and calcified protrusion, eruptive calcified nodules had the greatest calcium burden and a higher rate of stent edge dissection (p < 0.001) and incomplete stent apposition (p < 0.001). In a median follow-up period of 2 years, 39 (15.1%) patients experienced MACE (a composite event of cardiac death, target-vessel myocardial infarction, ischemia-driven revascularization), with a significantly higher incidence in the eruptive calcified nodules group (32.1% vs. 10.1% vs. 13.0%, p = 0.001). A multivariate Cox analysis demonstrated that the eruptive calcified nodules (hazard ratio 3.14; 95% confidence interval, 1.64–6.02; p = 0.001) were an independent predictor of MACE. Conclusions: MACE occurred more frequently in ACS patients with eruptive calcified nodules, and the eruptive calcified nodules were an independent predictor of MACE.

Evaluation of Stent Apposition in the LVIS Blue Stent-Assisted Coiling of Distal Internal Carotid Artery Aneurysms : Correlation with Clinical and Angiographic Outcomes.

To evaluate the stent apposition of a low-profile visualized intraluminal support (LVIS) device in distal internal carotid artery (ICA) aneurysms, examine its correlation with clinical and angiographic outcomes, and determine the predictive factors of ischemic adverse events (IAEs) related to stent-assisted coiling. We retrospectively analyzed a prospectively maintained database of 183 patients between January 2017 and February 2020. The carotid siphon from the cavernous ICA to the ICA terminus was divided into posterior, anterior, and superior bends. The anterior bends were categorized into angled (V) and non-angled (C, U, and S) types depending on the morphology and measured angles. Complete stent apposition (CSA) and incomplete stent apposition (ISA) were evaluated using unsubtracted angiography and flat-panel detector computed tomography. Dual antiplatelet therapy with aspirin 200 mg and clopidogrel 75 mg was administered. Clopidogrel resistance was defined as fewer responders (≥10%, <40%) and non-responders (<10%) based on the percent inhibition (%INH) of the VerifyNow system. These were counteracted by a dose escalation to 150 mg for fewer responders or substitution with cilostazol 200 mg for non-responders. IAEs included intraoperative in-stent thrombosis, transient ischemic attack, cerebral infarction, and delayed in-stent stenosis. A multivariate logistic regression analysis was used to determine the predictive factors for ISA and IAEs. There were 33 ISAs (18.0%) and 27 IAEs (14.8%). The anterior bend angle was narrower in ISA (-4.16°±25.18°) than in CSA (23.52°±23.13°) (p<0.001). The V- and S-types were independently correlated with the ISA (p<0.001). However, treatment outcomes, including IAEs (15.3% vs. 12.1%), aneurysmal complete occlusion (91.3% vs. 88.6%), and recanalization (none of them), did not differ between CSA and ISA (p>0.05). The %INH of 27 IAEs (13.78%±14.78%) was significantly lower than that of 156 non-IAEs (26.82%±20.23%) (p<0.001). Non-responders to clopidogrel were the only significant predictive factor for IAEs (p=0.001). The angled and tortuous anatomical peculiarity of the carotid siphon caused ISA of the LVIS device; however, it did not affect clinical and angiographic outcomes, while the non-responders to clopidogrel affected the IAEs related to stent-assisted coiling.

Efficacy of shockwave C2 coronary intravascular lithotripsy for management of severely calcified left anterior descending stenosis

Severely calcified coronary lesions remain a formidable hurdle for percutaneous coronary intervention as it averts the stent delivery and complete stent apposition. To overcome this Achilles heel of an interventional cardiology, a current US FDA approved method named shockwave intravascular lithotripsy (S-IVL; Shockwave Medical, Inc) is used for its treatment. Herein, we report a case of a 53-year-old dyslipidemic male with severely calcified left anterior descending artery (LAD) lesion that was successfully treated with S-IVL and drug-eluting stent implantation. At first, the patient was presented with complaints of chest pain and breathlessness. His coronary angiogram revealed heavily calcified stenosis in diffuse mid LAD—completely totally occluded mid-diagonal (D) 1 that was checked through retrograde filling via collateral and calcified stenosis in ostial D2, mild stenosis in ostial left circumflex and mild stenosis at distal before crux 50% stenosis in dominant right coronary artery. Following this, it was decided to proceed with primary percutaneous coronary intervention with S-IVL to LAD. After successful delivery of S-IVL to LAD, a Tetriflex sirolimus eluting stent (Sahajanand Medical Technologies Ltd., Surat, India) was successfully implanted at LAD. Finally, the patient’s condition was stabilized and discharged after two days of index procedure.

Optical Coherence Tomography: An Eye Into the Coronary Artery.

Optical coherence tomography (OCT) is slowly but surely gaining a foothold in the hands of interventional cardiologists. Intraluminal and transmural contents of the coronary arteries are no longer elusive to the cardiologist's probing eye. Although the graduation of an interventionalist in imaging techniques right from naked eye angiographies to ultrasound-based coronary sonographies to the modern light-based OCT has been slow, with the increasing regularity of complex coronary cases in practice, such a transition is inevitable. Although intravascular ultrasound (IVUS) due to its robust clinical data has been the preferred imaging modality in recent years, OCT provides a distinct upgrade over it in many imaging and procedural aspects. Better image resolution, accurate estimation of the calcified lesion, and better evaluation of acute and chronic stent failure are the distinct advantages of OCT over IVUS. Despite the obvious imaging advantages of OCT, its clinical impact remains subdued. However, upcoming newer trials and data have been encouraging for expanding the use of OCT to wider indications in clinical utility. During percutaneous coronary intervention (PCI), OCT provides the detailed information (dissection, tissue prolapse, thrombi, and incomplete stent apposition) required for optimal stent deployment, which is the key to successfully reducing the major adverse cardiovascular event (MACE) and stent-related morbidities. The increasing use of OCT in complex bifurcation stenting involving the left main (LM) is being studied. Also, the traditional pitfalls of OCT, such as additional contrast load for image acquisition and stenting involving the ostial and proximal LM, have also been overcome recently. In this review, we discuss the interpretation of OCT images and its clinical impact on the outcome of procedures along with current barriers to its use and newer paradigms in which OCT is starting to become a promising tool for the interventionalist and what can be expected for the immediate future in the imaging world.

Oversizing of self-expanding Nitinol vascular stents – A biomechanical investigation in the superficial femoral artery

Despite being commonly employed to treat peripheral artery disease, self-expanding Nitinol stents are still associated with relatively high incidence of failure in the mid- and long-term due to in-stent restenosis or fatigue fracture. The practice of stent oversizing is necessary to obtain suitable lumen gain and apposition to the vessel wall, though it is regarded as a potential cause of negative clinical outcomes when mis-sizing occurs. The objective of this study was to develop a computational model to provide a better understanding of the structural effects of stent sizing in a patient-specific scenario, considering oversizing ratio OS, defined as the stent nominal diameter to the average vessel diameter, between 1.0 and 1.8. It was found that OS < 1.2 resulted in problematic short-term outcomes, with poor lumen gain and significant strut malapposition. Oversizing ratios that were in the range 1.2 ≤ OS ≤ 1.4 provided the optimum biomechanical performance following implantation, with improved lumen gain, reduced incomplete stent apposition and favourable predicted long-term fatigue performance. Excessive oversizing, OS > 1.4, did not provide any further benefit in outcomes, showing limited increases in lumen gain and unfavourable long-term performance, with higher mean strain values predicted from the fatigue analysis. Therefore, our findings predict that the optimal oversizing ratio for self-expanding Nitinol stents is in the range of 1.2 ≤ OS ≤ 1.4, which is similar to clinical observations, with this study providing detailed insight into the biomechanical basis for this.