Minimum Stent Research Articles

Stent Underexpansion Is an Underestimated Cause of Intrastent Restenosis: Insights From RESTO Registry.

Despite improvement in devices, in-stent restenosis remains a frequent and challenging complication of percutaneous coronary interventions. The RESTO (Morphological Parameters of In-Stent Restenosis Assessed and Identified by OCT [Optical Coherence Tomography]; study NCT04268875) was a prospective multicenter registry including patients presenting with coronary syndromes related to in-stent restenosis. All patients underwent preintervention OCT analysis, which led to analysis of in-stent restenosis phenotype, number of strut layers, and presence of stent underexpansion. The primary end point was the in-stent restenosis type according to the OCT morphological classification. The 1-year incidence of target vessel failure (a composite of death from cardiac causes, target-vessel myocardial infarction, or ischemia-driven target-vessel revascularization) was assessed. The study included 297 patients. The culprit stent was a drug-eluting stent in 74.2% of cases. OCT analysis revealed the presence of neoatherosclerosis in 57% (52% calcified), neointimal hyperplasia in 43% (58% homogeneous), stent underexpansion (minimal stent area <4.5 mm2) in 43%, and multiple stent layers in 30%. The prepercutaneous coronary intervention OCT analysis modified the operator's strategy for management in 30% of cases. Treatment involved drug-eluting stent implantation in 61.6% and drug-eluting balloon angioplasty in 36.1% of cases with only 63.2% optimal results. The 1-year target vessel failure incidence was 11% (95% CI, 9%-13%). Residual postpercutaneous coronary intervention stent underexpansion was associated with significantly higher target vessel failure incidence (19% [95% CI, 14%-24%] versus 7% [95% CI, 5-9], P=0.01). OCT identified neoatherosclerosis and neointimal hyperplasia in comparable proportions. Stent underexpansion was frequent and favored subsequent adverse clinical outcomes.

Optical frequency domain imaging-guided versus intravascular ultrasound-guided percutaneous coronary intervention for acute coronary syndromes: the OPINION ACS randomised trial.

The clinical benefits of optical frequency domain imaging (OFDI)-guided percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) remain unclear. We sought to compare intravascular ultrasound (IVUS)- and OFDI-guided PCI in patients with ACS. OPINION ACS is a multicentre, prospective, randomised, non-inferiority trial that compared OFDI-guided PCI with IVUS-guided PCI using current-generation drug-eluting stents in ACS patients (n=158). The primary endpoint was in-stent minimum lumen area (MLA), assessed using 8-month follow-up OFDI. Patients presented with ST-segment elevation myocardial infarction (55%), non-ST-segment elevation myocardial infarction (29%), or unstable angina pectoris (16%). PCI procedural success was achieved in all patients, with comparably low periprocedural complications rates in both groups. Immediately after PCI, the minimum stent area (p=0.096) tended to be smaller for OFDI versus IVUS guidance. Proximal stent edge dissection (p=0.012) and irregular protrusion (p=0.03) were significantly less frequent in OFDI-guided procedures than in IVUS-guided procedures. Post-PCI coronary flow, assessed using corrected Thrombolysis in Myocardial Infarction frame counts, was significantly better in the OFDI-guided group than in the IVUS-guided group (p<0.001). The least squares mean (95% confidence interval [CI]) in-stent MLA at 8 months was 4.91 (95% CI: 4.53-5.30) mm2 and 4.76 (95% CI: 4.35-5.17) mm2 in the OFDI- and IVUS-guided groups, respectively, demonstrating the non-inferiority of OFDI guidance (pnon-inferiority<0.001). The average neointima area tended to be smaller in the OFDI-guided group. The frequency of major adverse cardiac events was similar. Among ACS patients, OFDI-guided PCI and IVUS-guided PCI were equally safe and feasible, with comparable in-stent MLA at 8 months. OFDI guidance may be a potential option in ACS patients. This study was registered in the Japan Registry of Clinical Trials (jrct.niph.go.jp: jRCTs052190093).

Optical coherence tomography predictors of clinical outcomes after stent implantation: the ILUMIEN IV trial.

Observational registries have suggested that optical coherence tomography (OCT) imaging-derived parameters may predict adverse events after drug-eluting stent (DES) implantation. The present analysis sought to determine the OCT predictors of clinical outcomes from the large-scale ILUMIEN IV trial. ILUMIEN IV was a prospective, single-blind trial of 2487 patients with diabetes or high-risk lesions randomized to OCT-guided versus angiography-guided DES implantation. All patients underwent final OCT imaging (blinded in the angiography-guided arm). From more than 20 candidates, the independent OCT predictors of 2-year target lesion failure (TLF; the primary endpoint), cardiac death or target-vessel myocardial infarction (TV-MI), ischaemia-driven target lesion revascularization (ID-TLR), and stent thrombosis were analysed by multivariable Cox proportional hazard regression in single treated lesions. A total of 2128 patients had a single treated lesion with core laboratory-analysed final OCT. The 2-year Kaplan-Meier rates of TLF, cardiac death or TV-MI, ID-TLR, and stent thrombosis were 6.3% (n = 130), 3.3% (n = 68), 4.3% (n = 87), and 0.9% (n = 18), respectively. The independent predictors of 2-year TLF were a smaller minimal stent area (per 1 mm2 increase: hazard ratio 0.76, 95% confidence interval 0.68-0.89, P < .0001) and proximal edge dissection (hazard ratio 1.77, 95% confidence interval 1.20-2.62, P = .004). The independent predictors of cardiac death or TV-MI were smaller minimal stent area and longer stent length; of ID-TLR were smaller intra-stent flow area and proximal edge dissection; and of stent thrombosis was smaller minimal stent expansion. In the ILUMIEN IV trial, the most important OCT-derived post-DES predictors of both safety and effectiveness outcomes were parameters related to stent area, expansion and flow, proximal edge dissection, and stent length.

Double Kissing Mini-Culotte Stenting in Unprotected Distal Left Main Bifurcation Under Optical Coherence Tomography Guidance: Immediate and Short-Term Outcomes

IntroductionCulotte stenting is an effective strategy for left main coronary bifurcation lesions. Increased side branch ostial restenosis is the main drawback of Culotte stenting. This is due to a napkin ring or potential gap produced at the ostium of the side branch. A bench study by Toth et al. has shown that additional sequential kissing balloon dilation before main vessel stenting can prevent this deformity. AimWe report immediate and short-term results of Double Kissing (DK) mini-Culotte stenting with a one-year angiographic follow-up. MethodsForty-five patients of distal left main (LM) disease underwent DK mini-Culotte stenting at our center between March 2020 and December 2022 under Optical Coherence Tomography (OCT) guidance. ResultsOut of 45 patients [male:35(77.77%); mean age:63.67±4.94years], chronic coronary syndrome was present in 26(57.8%) and unstable angina in rest. All lesions were Medina (1,1,1), (0,1,1), or (1,0,1) with a median Syntax score of 28 (IQR=23-29). All procedures were technically successful with no adverse clinical events (death, myocardial infarction, or stent thrombosis). Under OCT guidance, adequate minimal stent area (MSA) of 13.28 ± 0.77mm2, 8.25 ± 0.29 mm2, and 7.54 ± 0.45mm2 was achieved in LM, left anterior descending (LAD) and left circumflex (LCx) respectively. Adequate stent expansion of >80% was achieved in all cases. At the end of 1 year, the incidence of major adverse cardiovascular events (MACE) was 2.2%. Further, one (2.2%) patient developed restenosis of the side branch which was managed conservatively. ConclusionDK mini-Culotte stenting in the distal left main bifurcation has shown promising results and is effective in preventing side branch stent deformation and its sequelae of in-stent restenosis.

A risk score for predicting in-stent restenosis in patients with premature acute myocardial infarction undergoing percutaneous coronary intervention with drug-eluting stent

BackgroundThis study aimed at developing and validating a risk score to predict in-stent restenosis (ISR) in patients with premature acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) with drug-eluting stent (DES). MethodsThis was a two-center retrospective study. A total of 2185 patients firstly diagnosed with premature AMI (age ≥18 years and <55 years in men, <65 years in women) from Xinjiang cohort were retrospectively analyzed. After filtering by exclusion criteria, patients were randomly divided into training cohort (n = 434) and internal validation cohort (n = 186) at a 7:3 ratio. Several candidate variables associated with ISR in the training cohort were assessed by the least absolute shrinkage and selection operator and logistic regression analysis. The ISR risk nomogram score based on the superior predictors was finally developed, and then validated in the internal validation cohort and in an independent Chengdu external validation cohort (n = 192). The higher total nomogram score, the greater the ISR risk. ResultsThe eight variables in the final risk nomogram score, cardiovascular-kidney-metabolic (CKM) score included age, diabetes mellitus (DM), body mass index (BMI), systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDLC), estimated glomerular filtration rate (eGFR), stent in left anterior descending coronary artery, minimum stent diameter <3 mm. The areas under the curve (AUC) and C-statistics [training cohort: 0.834 (95%CI: 0.787 to 0.882); internal validation cohort: 0.852 (95%CI: 0.784 to 0.921); Chengdu external validation cohort: 0.787 (95%CI: 0.692 to 0.882), respectively)] demonstrated the good discrimination of the CKM score. The Hosmer-Lemeshow test (χ2 = 7.86, P = 0.448; χ2 = 5.17, P = 0.740; χ2 = 6.35, P = 0.608, respectively) and the calibration curve confirmed the good calibration of the CKM score. Decision curve analysis (DCA) testified the clinical net benefit of the CKM score in the training and validation cohort. ConclusionThis study provided a well-developed and validated risk nomogram score, the CKM score to predict ISR in patients with premature AMI undergoing PCI with DES. Given that these variables are readily available and practical, the CKM score should be widely adopted for individualized assessment and management of premature AMI.

Bicuspid valve CT registry of balloon-expandable TAVR: BETTER TAVR registry.

The anatomic substrate of bicuspid valves may lead to suboptimal TAVR stent expansion and geometry. We evaluated determinants of stent geometry in bicuspid valves treated with Sapien transcatheter aortic valve replacement (TAVR) valves. A multicenter retrospective registry of patients (February 2019 to August 2022) who underwent post-TAVR computed tomography to determine stent area (vs. nominal valve area) and stent ellipticity (maximum diameter/minimum diameter). Predictors of relative stent expansion (minimum area/average of inflow + outflow area) and stent ellipticity were evaluated in a multivariable regression model, including valve calcium volume (indexed by annular area), presence of raphe calcium, sinus diameters indexed by area-derived annular diameter, and performance of pre-dilation and post-dilation. The registry enrolled 101 patients from four centers. The minimum stent area (vs. nominal area) was 88.1%, and the maximum ellipticity was 1.10, with both observed near the midframe of the valve in all cases. Relative stent expansion ≥90% was observed in 64/101 patients. The only significant predictor of relative stent expansion ≥90% was the performance of post-dilation (OR: 4.79, p = 0.018). Relative stent expansion ≥90% was seen in 86% of patients with post-dilation compared to 57% without (p < 0.001). The stent ellipticity ≥1.1 was observed in 47/101 patients. The significant predictors of stent ellipticity ≥1.1 were the indexed maximum sinus diameter (OR: 0.582, p = 0.021) and indexed intercommisural diameter at 4 mm (OR: 2.42, p = 0.001). Stent expansion has a weak negative correlation with post-TAVR mean gradient (r = -0.324, p < 0.001). Relative stent expansion ≥90% was associated with the performance of post-dilation, and stent ellipticity ≥1.1 was associated with indexed intercommisural diameter and indexed maximum sinus diameter. Further studies to determine optimal deployment strategies in bicuspid valves are needed.

OCT-Guided vs Angiography-Guided Coronary Stent Implantation in Complex Lesions: An ILUMIEN IV Substudy

BackgroundILUMIEN IV was the first large-scale, multicenter, randomized trial comparing optical coherence tomography (OCT)-guided vs angiography-guided stent implantation in patients with high-risk clinical characteristics and/or complex angiographic lesions. ObjectivesThe authors aimed to specifically examine outcomes in the complex angiographic lesions subgroup. MethodsFrom the original trial population (N = 2,487), high-risk patients without complex angiographic lesions were excluded (n = 514). Complex angiographic lesion characteristics included: 1) long or multiple lesions with intended total stent length ≥28 mm; 2) bifurcation lesion with intended 2-stent strategy; 3) severely calcified lesion; 4) chronic total occlusion; or 5) in-stent restenosis. The study endpoints were: 1) final minimal stent area (MSA); 2) 2-year composite of serious major adverse cardiovascular events (MACEs) (cardiac death, target-vessel myocardial infarction [MI], or stent thrombosis); and 3) 2-year effectiveness, defined as target-vessel failure (TVF), a composite of cardiac death, target-vessel MI, or ischemia-driven target-vessel revascularization. ResultsThe postpercutaneous coronary intervention (PCI) MSA was larger in the OCT-guided (n = 992) vs angiography-guided (n = 981) group (5.56 ± 1.95 mm2 vs 5.26 ± 1.81 mm2; difference, 0.30; 95% CI: 0.14-0.47; P < 0.001). Compared with angiography-guided PCI, OCT-guided PCI resulted in a lower risk of serious MACE (3.1% vs 4.9%; HR: 0.63; 95% CI: 0.40-0.99; P = 0.04). TVF was not significantly different between groups (7.3% vs 8.8%; HR: 0.82; 95% CI: 0.59-1.12; P = 0.20). ConclusionsIn complex angiographic lesions, OCT-guided PCI led to a larger MSA and reduced the serious MACE, the composite of cardiac death, target-vessel MI, or stent thrombosis, compared with angiography-guided PCI at 2 years, but did not significantly improve TVF. (Optical Coherence Tomography Guided Coronary Stent Implantation Compared to Angiography: A Multicenter Randomized Trial in PCI; NCT03507777)

Fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation (FLASH): Study protocol for a randomized controlled noninferiority trial

BackgroundArtificial intelligence-based quantitative coronary angiography (AI-QCA) has been developed to provide a more objective and reproducible data about the severity of coronary artery stenosis and the dimensions of the vessel for intervention in real-time, overcoming the limitations of significant inter- and intraobserver variability, and time-consuming nature of on-site QCA, without requiring extra time and effort. Compared with the subjective nature of visually estimated conventional CAG guidance, AI-QCA guidance provides a more practical and standardized angiography-based approach. Although the advantage of intravascular imaging-guided PCI is increasingly recognized, their broader adoption is limited by clinical and economic barriers in many catheterization laboratories. MethodsThe FLASH (fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation) trial is a randomized, investigator-initiated, multicenter, open-label, noninferiority trial comparing the AI-QCA-assisted PCI strategy with optical coherence tomography-guided PCI strategy in patients with significant coronary artery disease. All operators will utilize a novel, standardized AI-QCA software and PCI protocol in the AI-QCA-assisted group. A total of 400 patients will be randomized to either group at a 1:1 ratio. The primary endpoint is the minimal stent area (mm2), determined by the final OCT run after completion of PCI. Clinical follow-up and cost-effectiveness evaluations are planned at 1 month and 6 months for all patients enrolled in the study. ResultsEnrollment of a total of 400 patients from the 13 participating centers in South Korea will be completed in February 2024. Follow-up of the last enrolled patients will be completed in August 2024, and primary results will be available by late 2024. ConclusionThe FLASH is the first clinical trial to evaluate the feasibility of AI-QCA-assisted PCI, and will provide the clinical evidence on AI-QCA assistance in the field of coronary intervention. Clinical trial registrationURL: https://www.clinicaltrials.gov. Unique identifier: NCT05388357.

Impact of coronary calcium morphology on intravascular lithotripsy.

Coronary calcification negatively impacts optimal stenting. Intravascular lithotripsy (IVL) is a new calcium modification technique. We aimed to assess the impact of different calcium morphologies on IVL efficacy. This was a prospective, multicentre study (13 tertiary referral centres). Optical coherence tomography (OCT) was performed before and after IVL, and after stenting. OCT-defined calcium morphologies were concentric (mean calcium arc >180°) and eccentric (mean calcium arc ≤180°). The primary outcomes were angiographic success (residual stenosis <20%) and the presence of fracture by OCT in concentric versus eccentric lesions. Ninety patients were included with a total of 95 lesions: 47 concentric and 48 eccentric. The median number of pulses was 60 (p=1.00). Following IVL, the presence of fracture was not statistically different between groups (79.0% vs 66.0% for concentric vs eccentric; p=0.165). The number of fractures/lesion (4.2±4.4 vs 2.3±2.8; p=0.018) and ≥3 fractures/lesion (57.1% vs 34.0%; p=0.029) were more common in concentric lesions. Angiographic success was numerically but not statistically higher in the concentric group (87.0% vs 76.6%; p=0.196). By OCT, no differences were noted in final minimum lumen area (5.9±2.2 mm2 vs 6.2±2.1 mm2; p=0.570), minimum stent area (5.9±2.2 mm² vs 6.25±2.4 mm2; p=0.483), minimum stent expansion (80.9±16.7% vs 78.2±19.8%), or stent expansion at the maximum calcium site (100.6±24.2% vs 95.8±27.3%) (p>0.05 for all comparisons of concentric vs eccentric, respectively). Calcified nodules were found in 29.5% of lesions; these were predominantly non-eruptive (57%). At the nodule site, dissection was more common than fracture with stent expansion of 103.6±27.2%. In this prospective, multicentre study, the effectiveness of IVL followed by stenting was not significantly affected by coronary calcium morphology.

Coronary laser with simultaneous contrast injection for the treatment of stent underexpansion.

Stent underexpansion is a challenge in interventional cardiology. Some off-label treatments, such as rotational atherectomy, intravascular lithotripsy (IVL) and coronary lasing, have been used to overcome the problem. The purpose of this study is to evaluate the safety and efficacy of coronary laser atherectomy with simultaneous contrast injection and subsequent balloon dilation to optimize stent expansion. Coronary laser atherectomy with simultaneous contrast injection was used. After lasing, non-compliant balloon dilation at high pressure was performed to overcome the underexpanded point. The average increase in the minimum stent area (MSA) was measured by intravascular ultrasound (IVUS), and any complication related to the technique was evaluated. Additionally, major adverse cardiovascular events (MACE), consisting of death from any cause, new myocardial infarction (MI) and target lesion revascularization (TLR), were scrutinized in a long-term follow-up. Sixteen underexpanded stents were treated with laser between August 2017 and November 2022. In all cases but one, IVUS was used to evaluate the MSA before and after lasing. The MSA showed an average increase of 2.34 ± 1.57 mm² (95% confidence interval [CI]: 1.47-3.21; p < 0.001) after laser application and balloon inflation. No complication related to the technique was detected. During a follow-up period of a median (interquartile range) of 457 (50-973) days, the combined MACE assessed by Kaplan-Meier estimator showed an event-free rate of 0.82 (95% CI: 0.59-1). Coronary laser with simultaneous contrast injection is a safe method to optimize a stent underexpansion, with an acceptable event-free rate in long-term follow-up.

Coronary intravascular lithotripsy in contemporary practice: challenges and opportunities in coronary intervention.

Percutaneous coronary intervention (PCI) of calcified coronary arteries is associated with poor outcomes. Poorly modified calcified lesion hinders the stent delivery, disrupts drug-carrying polymer, impairs drug elution kinetics and results in under-expanded stent (UES). UES is the most common cause of acute stent thrombosis and in-stent restenosis after PCI of calcified lesions. Angiography has poor sensitivity for recognition and quantification of coronary calcium, thereby mandating the use of intravascular imaging. Intravascular imaging, like intravascular ultrasound and optical coherence tomography, has the potential to accurately identify and quantify the coronary calcium and to guide appropriate modification device before stent placement. Available options for the modification of calcified plaque include modified balloons (cutting balloon, scoring balloon and high-pressure balloon), atherectomy devices (rotational atherectomy and orbital atherectomy) and laser atherectomy. Coronary intravascular lithotripsy (IVL) is the newest addition to the tool box for calcified plaque modification. It produces the acoustic shockwaves, which interact with the coronary calcium to cause multiplanar fractures. These calcium fractures increase the vessel compliance and result in desirable minimum stent areas. Coronary IVL has established its safety and efficacy for calcified lesion in series of Disrupt CAD trials. Its advantages over atherectomy devices include ease of use on workhorse wire, ability to modify deep calcium, no debris embolization causing slow flow or no-flow and minimal thermal injury. It is showing promising results in modification of difficult calcified lesion subsets such as calcified nodule, calcified left main bifurcation lesions and chronic total occlusion. In this review, authors will summarize the mechanism of action for IVL, its role in contemporary practice, evidence available for its use, its advantages over atherectomy devices and its imaging insight in different calcified lesion scenarios.

Optimal Minimal Stent Area and Impact of Stent Underexpansion in Left Main Up-Front 2-Stent Strategy.

We previously reported the use of minimal stent area to predict angiographic in-stent restenosis after drug-eluting stent implantation for unprotected left main (LM) disease. We aimed to evaluate the optimal minimal stent area criteria for up-front LM 2-stenting based on long-term clinical outcomes. We identified 292 consecutive patients with LM bifurcation stenosis who were treated using the crush technique. The final minimal stent area was measured in the ostial left anterior descending artery (LAD), ostial left circumflex artery (LCX), and distal LM. The primary outcome was 5-year major adverse cardiac events, including all-cause death, myocardial infarction, and target lesion revascularization. The minimal stent area cutoff values that best predicted the 5-year major adverse cardiac events were 11.8 mm2 for distal LM (area under the curve, 0.57; P=0.15), 8.3 mm2 for LAD ostium (area under the curve, 0.62; P=0.02), and 5.7 mm2 for LCX ostium (area under the curve, 0.64; P=0.01). Using these criteria, the risk of 5-year major adverse cardiac events was significantly associated with stent underexpansion in the LAD ostium (hazard ratio, 3.14; [95% CI, 1.23-8.06]; P=0.02) and LCX ostium (hazard ratio, 2.60 [95% CI, 1.11-6.07]; P=0.03) but not in the distal LM (hazard ratio, 0.81 [95% CI, 0.34-1.91]; P=0.63). Patients with stent underexpansion in both ostial LAD and LCX had a significantly higher rate of 5-year major adverse cardiac events than those with no or 1 underexpanded stent of either ostium (P<0.01). Stent underexpansion in the LAD and LCX ostium was significantly associated with long-term outcomes in patients who underwent up-front 2-stenting for LM bifurcation stenosis.

Retrospective Multicenter Analysis of Intravascular Lithotripsy Use During Calcified Left Main Coronary Artery Percutaneous Coronary Interventions

BackgroundIntravascular lithotripsy (IVL) safely and effectively modifies calcified coronary lesions during percutaneous coronary interventions (PCI). Data regarding its utility in modifying calcified left main coronary artery (LMCA) disease are limited. This study aimed to evaluate short-term outcomes of IVL-assisted LMCA PCI. MethodsThis retrospective multicenter all-comers study analyzed patients who underwent intravascular imaging-guided, IVL-assisted PCI for calcified LMCA disease. Clinical and procedural characteristics were obtained, including intravascular imaging measurements. Technical success was defined as successful stent deployment with <30% residual diameter stenosis. Major adverse cardiac events (MACE) was a composite of all-cause death, myocardial infarction, and target vessel revascularization evaluated immediately postprocedure and at 30-day follow-up. ResultsAmong 184 patients treated at 7 centers from 2019-2023, IVL-assisted LMCA PCI achieved 99.4% technical success. Calcium fracture was identified in 136/165 cases (82.4%) on post-IVL imaging. Pretreatment minimal luminal area increased significantly compared to post-PCI minimal stent area (MSA) (4.1 ± 1.3 to 9.3 ± 2.5 mm2, respectively; P < .001). There was a direct correlation between IVL balloon size and the final MSA (P = .002). In-hospital MACE was 4.4% and 30-day MACE was 8.8%. In multivariate logistic regression, presentation with troponin-positive myocardial infarction was the sole predictor of 30-day MACE. ConclusionsIVL-assisted PCI for calcified LMCA lesions was safe and resulted in high technical success rates, confirming its utility as an effective treatment in this challenging lesion subset.

Minimum stent area, stent expansion and ultrasonic flow ratio post pci: insights from multivessel talent trial

Abstract Background Ultrasonic flow ratio (UFR) is a novel method for fast computation of fractional flow reserve (FFR) from intravascular ultrasound. Recently studies have shown the feasibility of morphofunctional computational methods to reliably estimate coronary physiology from intravascular ultrasound images. Purpose To assess minimum stent area and stent expansion and its relation to ultrasonic flow ratio post percutaneous coronary intervention. Methods The study population consisted of 150 consecutive patients (280 vessels) who underwent intravascular ultrasound for optimization of PCI for three vessel disease as mandated in the ongoing MULTIVESSEL TALENT trial (NCT04390672). The UFR analysis was performed at the CORRIB Core Lab by an analyst who was blinded to the clinical data using a prototype software package (IvusPlus prototype, Pulse Medical Imaging Technology, Shanghai, China). The stent expansion and minimum stent area was automatically detected by the software. Results The median and mean UFR of 280 vessels post-PCI was 0.94 (0.91-0.97).and 0.93±0.04, respectively. Twenty three percent (n=115) of the 280 vessels had a UFR less than 0.91.The average minimum stent area (MSA) among the population was 5.82 ± 1.95 mm2. The mean stent expansion among the population was 97% ± 22%. We compared the site reported MSA with the software derived MSA which showed strong correlation (r=0.859; P&amp;lt;0.001). There was no correlation between MSA and UFR (r= -0.13, P=0.81). The stent expansion among patients who had UFR &amp;lt;0.91 when compared to ≥0.91 was significantly lower (82% vs 98%, P&amp;lt;0.001). The delta UFR within the stent was significantly higher in patients who had a UFR&amp;lt;0.94 vs ≥0.94 (0.06 vs 0.02; P&amp;lt;0.01). Delta UFR within the stent was higher when the stent expansion was &amp;lt;80% and &amp;lt;90% when compared to &amp;gt;80% and &amp;gt;90% (0.07 vs 0.03; P&amp;lt;0.01) and (0.06 vs 0.02; P&amp;lt;0.01) respectively. Conclusion Combination of IVUS and FFR enables the operator to conform to highest standards in PCI. This study demonstrates that UFR is not related to the minimum stent area, and patients who have UFR &amp;lt;0.94 have sub-optimal stent expansion.MSA and UFRUFR and Stent expansion

Abstract 17708: Cardiac Nut-Cracker: Paroxysmal Left Main Coronary Compression by Inducible Pulmonary Trunk Dilatation in Pulmonary Hypertension

Case Presentation: A 56yo woman with a 12-year history of idiopathic pHTN and severe RV dysfunction presented with worsening exertional angina (CCS III). Perfusion imaging demonstrated a large apical-septal defect, corresponding to an 80% eccentric stenosis of the LMCA on angiography ( Fig 1AB ) due to compression on ostium and shaft by a severely dilated pulmonary trunk ( Fig 1C ). Right heart catheterization revealed pulmonary artery pressures (PAPs) of 90/40/68mmHg. Operative risk for CABG was deemed prohibitive, thus the patient underwent high-risk PCI of the LMCA under IV conscious sedation. Initial angiography confirmed a patent LMCA with minimal longitudinal compression. Opening PAPs (102/37/64mmHg) with supplemental oxygen (FiO 2 /PaO 2 0.76/168mmHg) were similar to preop findings ( Fig 1D ). To replicate her symptomatology, supplemental oxygen was discontinued, resulting in rapid worsening of LMCA compression with severe reduction in LMCA cross-sectional area at room air conditions (FiO 2 /PaO 2 0.21/70mmHg), with corresponding suprasystemic PAP (122/44/73mmHg) ( Fig 1E) . Under IVUS guidance, a preselected stent was deployed producing complete LMCA patency without evidence of dynamic compression; minimal stent areas were unchanged at supraphysiologic and physiologic conditions: 19 vs 20mm 2 , FiO 2 0.73 vs 0.21 ( Fig 1F ). Discussion: LMCA stenosis from extrinsic compression of the vessel by an enlarged pulmonary artery is a rare etiology of acute coronary syndromes. Treatment options include PCI, CABG, reimplantation, or PA reduction plasty. While preop imaging clearly demonstrated LMCA compression by a dilated PA, during PCI true and dynamic severity of LMCA compression was revealed only under “normoxic conditions” (FiO 2 0.21). This paroxysmal “nut-cracker” phenomenon from inadvertent reversal of dynamic LMCA compression highlights the importance of normoxia in making the diagnosis of such anomalies in susceptible individuals with pHTN.

Modified balloons to prepare severely calcified coronary lesions before stent implantation: a systematic review and meta-analysis of randomized trials

BackgroundThe performance of modified balloons (namely cutting or scoring balloons) to prepare severely calcified lesions in patients undergoing percutaneous coronary intervention (PCI) remains controversial. We investigated the clinical and imaging outcomes of patients undergoing PCI assigned to modified balloon therapy to prepare severely calcified coronary lesions before stent implantation.MethodsIn this meta-analysis, we aggregated the study-level data from trials enrolling invasively treated patients who were randomly assigned to modified balloon or control therapy to prepare severely calcified lesions before stenting. The primary outcome was major adverse cardiac events (MACE), including death, myocardial infarction (MI), and repeat revascularization. The secondary outcomes included the individual components of the primary outcome, coronary perforation and final minimal stent area (MSA) as measured by intracoronary imaging.ResultsA total of 648 participants in six trials were allocated to modified balloon therapy (n = 335) or control therapy (semi-compliant, non-compliant, or super high-pressure balloon, n = 313). The median follow-up was 11 months. Overall, MACE occurred in 8.96% of patients assigned to a modified balloon and 12.78% of patients assigned to control therapy [risk ratio = 0.70, 95% confidence interval (CI) 0.35–1.39; P = 0.24]. There was a significant treatment effect-by-modified balloon type interaction for the outcome MACE in patients assigned to cutting balloon compared with control therapy [RR = 0.40 (0.28–0.56), P for interaction (Pint) < 0.001]. Patients treated with a modified balloon compared with control therapy showed neither a significant difference for the other clinical outcomes nor for final MSA [standardized mean difference = 0.67 (− 0.71, 2.06); P = 0.26].ConclusionsIn patients treated with PCI for severely calcific coronary artery disease a strategy of lesion preparation with a modified balloon before stenting does not improve clinical or imaging outcomes compared with control therapy. The different performance of cutting and scoring balloons warrants further investigation.Graphical

ISR vs De Novo Lesion Treatment During OCT-Guided PCI: Insights From the LightLab Initiative.

Long-term outcomes after percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) are poor, yet limited granular procedural data exist evaluating lesion assessment, vessel treatment, and acute procedural outcomes. The LightLab Initiative was a multicenter, prospective, observational study with contemporaneous procedural data collection during PCI procedures. Data were collected during PCIs performed by 48 interventional cardiologists at 17 US hospitals (2019-2021). Optical coherence tomography (OCT) was performed pre-PCI for lesion assessment and post-PCI for stent optimization, and results were compared between ISR and de novo lesion PCI. In total, 2592 OCT-guided PCIs involving 2944 lesions were included, of which 458 procedures (17.7%) were ISR PCI. Compared with de novo lesion PCI, ISR lesions were more commonly type C (64.8% vs 52.9%) and performed via femoral artery access (46.4% vs 37.7%). Use of OCT changed operator assessment and treatment decisions more frequently in ISR PCI (94.2% vs 85.2%; P = .002). Scoring balloons (21.8% vs 2.5%), cutting balloons (16.4% vs 3.4%), and atherectomy (26.3% vs 9.9%) were used more commonly in ISR PCI (all P < .0001), and ISR PCI procedures were longer (62 vs 51 min). Moreover, the final achieved minimum stent area and percent expansion (4.4 vs 5.1 mm2 and 80% vs 83%, respectively; both P < .0001) were lower in ISR PCI. In this real-world cohort of patients who underwent OCT-guided PCI, ISR procedures were longer and final minimum stent area and percent expansion were lower despite greater use of advanced lesion modification. OCT frequently altered physician decision making, emphasizing its utility in potentially reducing recurrent stent failure in this high-risk population.

Impact of Procedural Techniques on Midterm Patency of Fluoropolymer-Based Drug-Eluting Stent Placed in the Femoropopliteal Artery

PurposeTo investigate the impact of compliance with recommended procedural techniques on the midterm patency of a fluoropolymer-based drug-eluting stent (FP-DES) in the femoropopliteal artery. Materials and MethodsThis retrospective study included 200 femoropopliteal lesions (chronic limb-threatening ischemia, 59%; chronic total occlusion, 41%) in 173 patients (male, 66%; diabetes mellitus, 62%; hemodialysis, 40%) with lower extremity arterial disease who underwent intravascular ultrasound (IVUS)-guided endovascular therapy with FP-DES between January 2016 and July 2021. The primary outcome measure was restenosis, defined as a peak systolic velocity ratio of >2.4 based on the duplex US findings. The association between procedural techniques and incidence of restenosis was investigated using Cox proportional hazards regression models. ResultsThe 2-year cumulative incidence of restenosis was 19.5% (SD ± 3.3). Multivariate analysis revealed that noncompliance with recommended procedural techniques, such as plaque burden at the stent edge of <50%, a minimum stent area (MSA) of >12 mm2, and stent placement within the P1 segment, was independently associated with an increased risk of restenosis (hazard ratios [HRs], 3.22, 4.71, and 4.67 and P = .004, P < .001, and P < .001, respectively). The 2-year restenosis risk for procedures performed in compliance with all 3-technical criteria was 8.4% (SD ± 3.4), whereas the risks for those in compliance with 2-technical criteria or 0- or 1-technical criteria were 25.0% (SD ± 6.2) and 48.6% (SD ± 10.4), respectively. HRs relative to 3-technical criteria compliance were 3.79 (P = .007) and 11.85 (P < .001), respectively. ConclusionsNoncompliance with recommended procedural techniques, including plaque burden at the stent edge of <50%, MSA of >12 mm2, and stent placement within the P1 segment, was significantly associated with an increased risk of 2-year restenosis after FP-DES implantation in the femoropopliteal artery.

Angiography and optical coherence tomography derived shear stress: are they equivalent in my opinion?

Advances in image reconstruction using either single or multimodality imaging data provide increasingly accurate three-dimensional (3D) patient's arterial models for shear stress evaluation using computational fluid dynamics (CFD). We aim to evaluate the impacts on endothelial shear stress (ESS) derived from a simple image reconstruction using 3D-quantitative coronary angiography (3D-QCA) versus a multimodality reconstruction method using optical coherence tomography (OCT) in patients' vessels treated with bioresorbable scaffolds. Seven vessels at baseline and five-year follow-up of seven patients from a previous CFD investigation were retrospectively selected for a head-to-head comparison of angiography-derived versus OCT-derived ESS. 3D-QCA significantly underestimated the minimum stent area [MSA] (-2.38mm2) and the stent length (-1.46mm) compared to OCT-fusion method reconstructions. After carefully co-registering the region of interest for all cases with a sophisticated statistical method, the difference in MSA measurements as well as the inability of angiography to visualise the strut footprint in the lumen surface have translated to higher angiography-derived ESS than OCT-derived ESS (1.76Pa or 1.52 times for the overlapping segment). The difference in ESS widened with a more restricted region of interest (1.97Pa or 1.63 times within the scaffold segment). Angiography and OCT offer two distinctive methods of ESS calculation. Angiography-derived ESS tends to overestimate the ESS compared to OCT-derived ESS. Further investigations into ESS analysis resolution play a vital role in adopting OCT-derived ESS.

Direct Comparison of Rotational vs Orbital Atherectomy for Calcified Lesions Guided by Optical Coherence Tomography

BackgroundThere are several retrospective studies comparing rotational atherectomy (RA) and orbital atherectomy (OA), but all percutaneous coronary interventions (PCIs) in those studies were not performed under intracoronary imaging guidance. ObjectivesThis study sought to compare the efficacy and safety of optical coherence tomography (OCT)-guided PCI with RA vs OA. MethodsThe DIRO (To directly compare RA and OA for calcified lesions, a prospective randomized trial) trial was conducted. We enrolled patients with de novo calcified lesions (arc >180°) assessed by OCT or angiographically moderate or severe calcifications if the OCT catheter could not cross the lesion before any intervention. Eligible patients were randomly 1:1 allocated to lesion preparation with RA vs OA. Stent expansion was defined as the minimum stent area divided by the distal reference area multiplied by 100. Tissue modification was assessed using preatherectomy and postatherectomy OCT images. Procedural outcomes including periprocedural myocardial infarctions were evaluated. Furthermore, clinical events and vascular healing evaluated by OCT at 8 months postprocedure were assessed. ResultsThe stent expansion was significantly greater in the RA group vs the OA group (99.5% vs 90.6%; P = 0.02). The maximum atherectomy area was significantly larger in the RA group than in the OA group (1.34 [IQR: 1.02-1.89] mm2 vs 0.83 [IQR: 0.59-1.11] mm2; P = 0.004). The procedural outcomes and clinical events at 8 months did not differ between the groups. The vascular healing was sufficient in both groups. ConclusionsThe prospective randomized DIRO trial revealed that RA could produce a more favorable tissue modification, which may lead to a larger stent expansion than OA in heavily calcified lesions.