Clinical Utility of Intravascular Imaging and Physiology in Coronary Artery Disease

Intravascular imaging and physiology techniques and technologies are moving beyond the framework of research to inform clinical decision making. Currently available technologies and techniques include fractional flow reserve; grayscale intravascular ultrasound (IVUS); IVUS radiofrequency tissue characterization; optical coherence tomography, the light analogue of IVUS; and near-infrared spectroscopy that detects lipid within the vessel wall and that has recently been combined with grayscale IVUS in a single catheter as the first combined imaging device. These tools can be used to answer questions that occur during daily practice, including: Is this stenosis significant? Where is the culprit lesion? Is this a vulnerable plaque? What is the likelihood of distal embolization or periprocedural myocardial infarction during stent implantation? How do I optimize acute stent results? Why did thrombosis or restenosis occur in this stent? One of the legacies of coronary angiography is to presume that one technique will answer all of these questions; however, that often has been proved inaccurate in contemporary practice.     

Stent Expansion Indexes to Predict Clinical Outcomes: An IVUS Substudy From ADAPT-DES

ObjectivesThe aim of this study was to evaluate various stent expansion indexes to determine the best predictor of clinical outcomes.BackgroundNumerous intravascular ultrasound (IVUS) studies have shown minimum stent area (MSA) to be the most powerful predictor of future events.MethodsADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) was a prospective, multicenter registry of 8,582 patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents. Native coronary artery lesions treated with IVUS-guided PCI with final analyzable IVUS were included. Ten stent expansion indexes (MSA, MSA/vessel area at MSA site, conventional stent expansion [MSA/average of proximal and distal reference luminal area], minimum stent expansion using Huo-Kassab or linear model accounting for vessel tapering, stent asymmetry [minimum/maximum stent diameter within the entire stent], stent eccentricity [smallest minimum/maximum stent diameter at a single slice within the stent], IVUS-XPL [Impact of intravascular Ultrasound Guidance on Outcomes of Xience Prime Stents in Long Lesions] criteria, ULTIMATE [Intravascular Ultrasound Guided Drug Eluting Stents Implantation in “All-Comers” Coronary Lesions] criteria, and ILUMIEN IV criteria) were evaluated for their associations with lesion-specific 2-year clinically driven target lesion revascularization (TLR) or definite stent thrombosis.ResultsOverall, 2,140 lesions in 1,831 patients were included; final MSA measured 6.2 ± 2.4 mm². Among the 10 stent expansion indexes, only MSA/vessel area at the MSA site was independently associated with 2-year clinically driven TLR or definite stent thrombosis (hazard ratio: 0.77; 95% confidence interval: 0.59-0.99; P = 0.04) after adjusting for morphologic and procedural parameters.ConclusionsIn this IVUS-guided PCI cohort with excellent final MSA overall, stent/vessel area at the MSA site, an index of relative stent expansion, was superior to absolute MSA and other expansion indexes in predicting 2-year clinically driven TLR or definite stent thrombosis.     

Intravascular Imaging During Percutaneous Coronary Intervention: JACC State-of-the-Art Review

Coronary angiography has historically served as the gold standard for diagnosis of coronary artery disease and guidance of percutaneous coronary intervention (PCI). Adjunctive use of contemporary intravascular imaging (IVI) technologies has emerged as a complement to conventional angiography—to further characterize plaque morphology and optimize the performance of PCI. IVI has utility for preintervention lesion and vessel assessment, periprocedural guidance of lesion preparation and stent deployment, and postintervention assessment of optimal endpoints and exclusion of complications. The role of IVI in reducing major adverse cardiac events in complex lesion subsets is emerging, and further studies evaluating broader use are underway or in development. This paper provides an overview of currently available IVI technologies, reviews data supporting their utilization for PCI guidance and optimization across a variety of lesion subsets, proposes best practices, and advocates for broader use of these technologies as a part of contemporary practice.     

Prediction of Coronary Stent Underexpansion by Pre-Procedural Intravascular Ultrasound–Based Deep Learning

ObjectivesThe aim of this study was to develop pre-procedural intravascular ultrasound (IVUS)–based models for predicting the occurrence of stent underexpansion.BackgroundAlthough post-stenting IVUS has been used to optimize percutaneous coronary intervention, there are no pre-procedural guidelines to estimate the degree of stent expansion and provide preemptive management before stent deployment.MethodsA total of 618 coronary lesions in 618 patients undergoing percutaneous coronary intervention were randomized into training and test sets in a 5:1 ratio. Following the coregistration of pre- and post-stenting IVUS images, the pre-procedural images and clinical information (stent diameter, length, and inflation pressure; balloon diameter; and maximal balloon pressure) were used to develop a regression model using a convolutional neural network to predict post-stenting stent area. To separate the frames with from those without the occurrence of underexpansion (stent area <5.5 mm²), binary classification models (XGBoost) were developed.ResultsOverall, the frequency of stent underexpansion was 15% (5,209 of 34,736 frames). At the frame level, stent areas predicted by the pre-procedural IVUS-based regression model significantly correlated with those measured on post-stenting IVUS (r = 0.802). To predict stent underexpansion, maximal accuracy of 94% (area under the curve = 0.94) was achieved when the convolutional neural network– and mask image–derived features were used for the classification model. At the lesion level, there were significant correlations between predicted and measured minimal stent area (r = 0.832) and between predicted and measured total stent volume (r = 0.958).ConclusionsDeep-learning algorithms accurately predicted incomplete stent expansion. A data-driven approach may assist clinicians in making treatment decisions to avoid stent underexpansion as a preventable cause of stent failure.     

Effect of Intravascular Ultrasound–Guided Drug-Eluting Stent Implantation: 5-Year Follow-Up of the IVUS-XPL Randomized Trial

ObjectivesThe goal of this study was to evaluate whether the beneficial effect of use of intravascular ultrasound (IVUS) is sustained for long-term follow-up.BackgroundThe use of IVUS promoted favorable 1-year clinical outcome in the IVUS-XPL (Impact of Intravascular Ultrasound Guidance on the Outcomes of Xience Prime Stents in Long Lesions) trial. It is not known, however, whether this effect is sustained for long-term follow-up.MethodsThe IVUS-XPL trial randomized 1,400 patients with long coronary lesions (implanted stent length ≥28 mm) to receive IVUS-guided (n = 700) or angiography-guided (n = 700) everolimus-eluting stent implantation. Five-year clinical outcomes were investigated in patients who completed the original trial. The primary outcome was the composite of major adverse cardiac events, including cardiac death, target lesion–related myocardial infarction, or ischemia-driven target lesion revascularization at 5 years, analyzed by intention-to-treat.ResultsFive-year follow-up was completed in 1,183 patients (85%). Major adverse cardiac events at 5 years occurred in 36 patients (5.6%) receiving IVUS guidance and in 70 patients (10.7%) receiving angiographic guidance (hazard ratio: 0.50; 95% confidence interval: 0.34 to 0.75; p = 0.001). The difference was driven mainly by a lower risk for target lesion revascularization (31 [4.8%] vs. 55 [8.4%]; hazard ratio: 0.54; 95% confidence interval: 0.33 to 0.89; p = 0.007). By landmark analysis, major adverse cardiac events between 1 and 5 years occurred in 17 patients (2.8%) receiving IVUS guidance and in 31 patients (5.2%) receiving angiographic guidance (hazard ratio: 0.53; 95% confidence interval: 0.29 to 0.95; p = 0.031).ConclusionsCompared with angiography-guided stent implantation, IVUS-guided stent implantation resulted in a significantly lower rate of major adverse cardiac events up to 5 years. Sustained 5-year clinical benefits resulted from both within 1 year and from 1 to 5 years post-implantation. (Impact of Intravascular Ultrasound Guidance on the Outcomes of Xience Prime Stents in Long Lesions [IVUS-XPL Study]: Retrospective and Prospective Follow-Up Study; NCT03866486)     

The Impact of Intravascular Ultrasound on Femoropopliteal Artery Endovascular Interventions: A Randomized Controlled Trial

ObjectivesThe aim of this study was to investigate whether the addition of intravascular ultrasound (IVUS) guidance during femoropopliteal artery interventions reduced the rate of binary restenosis within 12 months compared with angiographic guidance alone.BackgroundIVUS is more accurate than angiography for assessment of vessel size and disease severity. Low-level studies suggest that the use of IVUS in femoropopliteal endovascular interventions improves outcomes, but currently, no level 1 evidence exists.MethodsThis was a prospective single-center trial of 150 patients undergoing femoropopliteal endovascular intervention, randomized (1:1) to guidance by angiography or angiography and IVUS. The primary outcome measure was freedom from binary restenosis, on duplex ultrasound, within 12 months. Secondary outcomes included clinically driven target lesion revascularization, disagreements in imaging findings between modalities, and changes in treatment caused by IVUS.ResultsFreedom from binary restenosis at 12 months was significantly higher in the IVUS group (72.4% vs 55.4%; P = 0.008). There was no significant difference between groups for clinically directed target lesion revascularization (84.2% and 82.4%; P = 0.776). Mean vessel diameter was significantly larger with IVUS (5.60 mm vs 5.10 mm; P < 0.001). A change in treatment occurred caused by IVUS in 79% of cases. Binary restenosis was lower in the IVUS group for cases treated with drug-coated balloons (9.1% vs 37.5%; P = 0.001).ConclusionsThe use of IVUS resulted in a significant reduction in the rate of restenosis after endovascular intervention. This is the first randomized controlled trial to demonstrate that IVUS improves outcomes in femoropopliteal interventions. This benefit may primarily relate to cases treated with drug-coated balloons. (Does the use of intravascular ultrasound improve outcomes of endovascular interventional procedures for peripheral vascular disease of the superficial femoral artery or popliteal artery?; ACTRN12614000006640)     

Ultrathin,Biodegradable-Polymer Sirolimus-Eluting Stent vs Thin,Durable-Polymer Everolimus-Eluting Stent

BackgroundPrevious trials suggested the superiority of ultrathin- over thin-strut drug-eluting stents (DES) concerning target lesion failure (TLF) at 1 year after index percutaneous coronary intervention.ObjectivesThe aim of this randomized comparison study of ultrathin-strut and thin-strut DES (CASTLE [Randomized Comparison All-Comer Study of Ultrathin Strut and Thin Strut Drug-Eluting Stent]; jRCTs032180084) was to examine the impact of differences in strut thickness of DES on clinical outcomes when implanted with angiography and intravascular ultrasound or optical coherence tomographic guidance.MethodsCASTLE was a multicenter, prospective, noninferiority study conducted at 65 institutions in Japan. Percutaneous coronary intervention patients were assigned (1:1) to an ultrathin, biodegradable-polymer sirolimus-eluting stent (BP-SES) or a thin, durable-polymer everolimus-eluting stent (DP-EES). The primary endpoint was TLF, defined as a composite of cardiac death, target vessel–related myocardial infarction, and clinically driven target lesion revascularization at 1-year follow-up.ResultsBetween May 2019 and March 2020, 1,440 patients were randomly assigned to BP-SES (n = 722) or DP-EES (n = 718). TLF occurred in 6.0% and 5.7% of patients, respectively. Noninferiority (P = 0.040) was met because the upper limit (2.67%) of the 1-sided 95% CI between the groups was lower than the prespecified noninferiority margin (3.3%). No significant interactions were observed in the relative rates of TLF between prespecified subgroups.ConclusionsThe BP-SES was noninferior to the DP-EES regarding 1-year TLF. This demonstrates that strut thickness differences among DES have little impact on clinical outcomes when implanted with intravascular imaging guidance.     

Impact of Nonobstructive Left Main Coronary Artery Atherosclerosis on Long-Term Mortality

BackgroundAlthough the presence of severe stenosis in the left main coronary artery (LMCA) is a well-established predictor of mortality, whether this extends to nonobstructive atherosclerosis in the LMCA is unknown.ObjectivesThe aim of this study was to evaluate the association between LMCA disease by intravascular ultrasound (IVUS) and long-term mortality.MethodsBetween 2005 and 2013, 3,239 patients with LMCA IVUS imaging without LMCA revascularization (either before angiography or scheduled based on index angiography or IVUS) were included. The primary and secondary endpoints were all-cause and cardiac mortality at a minimum of 5 years obtained from the National Death Index.ResultsThe IVUS-measured LMCA minimum lumen area (MLA) and plaque burden were 13.1 ± 5.0 mm² and 41.7% ± 15.6%, respectively. The median follow-up was 8.2 years. The Kaplan-Meier estimated 12-year all-cause and cardiac death rates were 37.5% and 17.0%, respectively. Greater plaque burden (unadjusted HR per 10%: 1.17; 95% CI: 1.12-1.22; P < 0.0001) and smaller IVUS MLA (unadjusted HR per 1 mm²: 0.98; 95% CI: 0.96-0.99; P = 0.0008) were associated with all-cause death. After adjusting for clinical, angiographic, and IVUS factors, plaque burden (adjusted HR per 10%: 1.12; 95% CI: 1.04-1.21; P = 0.003) but not MLA (adjusted HR per 1 mm²: 1.02; 95% CI: 0.99-1.04; P = 0.18) was associated with long-term all-cause death. These findings were also consistent for long-term cardiac mortality.ConclusionsIn the present large-scale study with a 12-year follow-up, increasing LMCA plaque burden was associated with long-term all-cause and cardiac mortality in patients not undergoing LMCA revascularization, even when the lumen area was preserved.     

Influence of Anatomical and Clinical Characteristics on Long-Term Prognosis of FFR-Guided Deferred Coronary Lesions

ObjectivesThe aim of this study was to evaluate the clinical and anatomical features to predict the long-term outcomes in patients with fractional flow reserve (FFR)–guided deferred lesions, verified by intravascular ultrasound (IVUS).BackgroundDeferral of nonsignificant lesion by FFR is associated with a low risk of clinical events. However, the impact of combined information on clinical and anatomical factors is not well known.MethodsThe study included 459 patients with 552 intermediate lesions who had deferred revascularization on the basis of a nonischemic FFR (>0.80). Grayscale IVUS was examined simultaneously. The primary endpoint was patient-oriented composite outcome (POCO) (a composite of all-cause death, myocardial infarction, and any revascularization) during 5-year follow-up.ResultsThe rate of 5-year POCO was 9.8%. Diabetes mellitus (hazard ratio: 3.50; 95% confidence interval [CI]: 1.86 to 6.57; p < 0.001), left ventricular ejection fraction ≤40% (hazard ratio: 4.80; 95% CI: 1.57 to 14.63; p = 0.006), and positive remodeling (hazard ratio: 2.04; 95% CI: 1.03 to 4.03; p = 0.041) were independent predictors for POCO. When the lesions were classified according to the presence of the adverse clinical characteristics (diabetes, left ventricular ejection fraction ≤40%) or adverse plaque characteristics (positive remodeling, plaque burden ≥70%), the risk of POCO was incrementally increased (4.3%, 13.6%, and 21.3%, respectively; p < 0.001).ConclusionsIn patients with FFR-guided deferred lesions, 5-year clinical outcomes were excellent. Lesion-related anatomical factors from intravascular imaging as well as patient-related clinical factors could provide incremental information about future clinical risks.     

Association between abdominal fat distribution and coronary plaque instability in patients with acute coronary syndrome

Background and aimsThis study aimed to assess possible association of detailed abdominal fat profiles with coronary plaque characteristics in patients with acute coronary syndrome (ACS).Methods and resultsIn 60 patients with ACS, culprit arteries were evaluated at 1-mm intervals (length analyzed: 66 ± 28 mm) by grayscale and integrated backscatter intravascular ultrasound (IB-IVUS) before percutaneous coronary intervention. Standard IVUS indexes (as a volume index: volume/length), plaque components (as percent tissue volume) and fibrous cap thickness (FCT) were assessed by IB-IVUS. Plain abdominal computed tomography was performed to evaluate subcutaneous adipose tissue (SAT) area, visceral adipose tissue (VAT) area, and VAT/SAT ratio. While SAT area only correlated with vessel volume (r = 0.27, p = 0.04), VAT area correlated positively with vessel (r = 0.30, p = 0.02) and plaque (r = 0.33, p = 0.01) volumes and negatively with FCT (r = −0.26, p = 0.049), but not with percent plaque volume and plaque tissue components. In contrast, higher VAT/SAT ratio significantly correlated with higher percent lipid (r = 0.34, p = 0.008) and lower percent fibrous (r = −0.34, p = 0.007) volumes with a trend toward larger percent plaque volume (r = 0.19, p = 0.15), as well as thinner FCT (r = −0.53, p < 0.0001). In the multiple regression analysis, higher VAT/SAT ratio was independently associated with higher percent lipid with lower percent fibrous volumes (p = 0.03 for both) and thinner fibrous cap thickness (p = 0.0001).ConclusionCoronary plaque vulnerability, defined as increased lipid content with thinner fibrous cap thickness, appears to be more related to abnormal abdominal fat distribution, or so-called hidden obesity, compared with visceral or subcutaneous fat amount alone in patients with ACS.     

NIRS-IVUS for Differentiating Coronary Plaque Rupture,Erosion, and Calcified Nodule in Acute Myocardial Infarction

ObjectivesThis study sought to investigate the ability of combined near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) to differentiate plaque rupture (PR), plaque erosion (PE), or calcified nodule (CN) in acute myocardial infarction (AMI).BackgroundMost acute coronary syndromes occur from coronary thrombosis based on PR, PE, or CN. In vivo differentiation among PR, PE, and CN is a major challenge for intravascular imaging.MethodsThe study enrolled 244 patients with AMI who had a de novo culprit lesion in a native coronary artery. The culprit lesions were assessed by both NIRS-IVUS and optical coherence tomography (OCT). Maximum lipid core burden index in 4 mm (maxLCBI_4mm) was measured by NIRS. Plaque cavity and convex calcium was detected by IVUS. The OCT diagnosis of PR (n = 175), PE (n = 44), and CN (n = 25) was used as a reference standard.ResultsIn the development cohort, IVUS-detected plaque cavity showed a high specificity (100%) and intermediate sensitivity (62%) for identifying OCT-PR. IVUS-detected convex calcium showed a high sensitivity (93%) and specificity (100%) for identifying OCT-CN. NIRS-measured maxLCBI_4mm was largest in OCT-PR (705 [interquartile range (IQR): 545 to 854]), followed by OCT-CN (355 [IQR: 303 to 478]) and OCT-PE (300 [IQR: 126 to 357]) (p < 0.001). The optimal cutoff value of maxLCBI_4mm was 426 for differentiating between OCT-PR and -PE; 328 for differentiating between OCT-PE and -CN; and 579 for differentiating between OCT-PR and -CN. In the validation cohort, the NIRS-IVUS classification algorithm using plaque cavity, convex calcium, and maxLCBI_4mm showed a sensitivity and specificity of 97% and 96% for identifying OCT-PR, 93% and 99% for OCT-PE, and 100% and 99% for OCT-CN, respectively.ConclusionsBy evaluating plaque cavity, convex calcium, and maxLCBI_4mm, NIRS-IVUS can accurately differentiate PR, PE, and CN.     

Optimal Stenting Technique for Complex Coronary Lesions: Intracoronary Imaging-Guided Pre-Dilation,Stent Sizing,and Post-Dilation

ObjectivesThis study compared the 3-year outcomes of intracoronary imaging–guided pre-dilation, stent sizing, and post-dilation (iPSP) for patients with complex coronary artery lesions.BackgroundThe long-term effects of the optimal drug-eluting stent implantation technique in complex coronary artery disease have not been evaluated.MethodsFrom the IRIS-DES (Interventional Cardiology Research In-cooperation Society-Drug-Eluting Stents) registry, the study evaluated 9,525 patients who underwent percutaneous coronary intervention for left main, bifurcation, long or diffuse (>30 mm), or angiographically severely calcified lesions. The primary outcome was a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization. The inverse probability of treatment weighting method was used to adjust for confounding factors.ResultsAt the index procedure, intravascular ultrasound assessment PSP were performed in 8,522 (89.5%) patients, 5,141 (54.0%) patients, and 5,531 (58.1%) patients, respectively; overall, 3,374 (35.4%) patients underwent stent implantation using all 3 parts of the iPSP strategy and were defined as the iPSP group. At 3 years, the adjusted rate of the primary outcome was significantly lower in iPSP group (5.6% vs 7.9%; adjusted hazard ratio: 0.71; 95% confidence interval: 0.63 to 0.81; p < 0.001).ConclusionsAmong patients undergoing drug-eluting stent implantation in complex coronary artery stenosis, iPSP was associated with a lower risk of cardiac events at 3 years. Therefore, physicians should apply iPSP more actively for the treatment of complex coronary artery stenoses, even in the current era. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133)     

Tip Detection Method Using the New IVUS Facilitates the 3-Dimensional Wiring Technique for CTO Intervention

ObjectivesThis study assessed the efficacy of the tip detection method during intravascular ultrasound (IVUS)–based 3-dimensional (3D) wiring with a new chronic total occlusion (CTO)–specific IVUS system (AnteOwl IVUS [AO-IVUS]) for CTO percutaneous coronary intervention (PCI).BackgroundThe study developed angiography-based 3D wiring for CTO-PCI. Previously, the authors produced a short-tip CTO-specific IVUS system (Navifocus WR IVUS [Navi-IVUS]), which has been upgraded into the AO-IVUS system by adding a pullback transducer system for IVUS-based 3D wiring.MethodsA CTO lesion 20 mm in length composed of 2.5% agar was experimentally inserted into the coronary artery of a beating heart model. The target (a microcatheter with a 0.6-mm lumen) was placed in the distal part of the CTO lesion. IVUS-guided wiring was performed to insert the guidewire into the target using the Navi-IVUS and then using the AO-IVUS 8 times each. In wiring with AO-IVUS, the IVUS-based 3D wiring using the tip detection method was performed. The crossing time and the number of punctures to the target were calculated.ResultsThe crossing time was significantly shortened and the number of punctures was significantly reduced in AO-IVUS–based wiring compared with Navi-IVUS–based wiring (median crossing time 80.5 s [interquartile range: 44.0 to 112.3 s] vs. 333.0 s [interquartile range: 88.8 to 790.0 s]; p = 0.036; median 1.0 puncture [interquartile range: 1.0 to 2.0 punctures] vs. 24.0 punctures [interquartile range: 5.8 to 52.5 punctures]; p = 0.001).ConclusionsThe tip detection method enables the authors to easily perform the IVUS-based 3D wiring, and the new CTO IVUS system will facilitate this method in clinical practice.     

Plaque Rupture,Compared With Plaque Erosion,Is Associated With a Higher Level of Pancoronary Inflammation

ObjectivesThe aim of this study was to compare the level of coronary inflammation between plaque rupture and plaque erosion using pericoronary adipose tissue (PCAT) attenuation.BackgroundVascular inflammation plays a key role in plaque rupture, while the role of inflammation in plaque erosion remains less well defined. PCAT attenuation determined using computed tomography has emerged as a marker specific for coronary artery inflammation.MethodsPatients with non–ST-segment elevation acute coronary syndromes who underwent preintervention coronary computed tomographic angiography and optical coherence tomographic culprit lesion imaging were enrolled. PCAT attenuation was measured around the culprit lesion and in the proximal 40 mm of all coronary arteries.ResultsAmong 198 patients, plaque rupture was the underlying mechanism in 107 (54.0%) and plaque erosion in 91 (46.0%). Plaque rupture had higher PCAT attenuation than plaque erosion both at the culprit plaque level (?65.8 ± 7.5 HU vs ?69.5 ± 11.4 HU; P = 0.010) and at the culprit vessel level (?67.1 ± 7.1 HU vs ?69.6 ± 8.2 HU; P = 0.024). The mean PCAT attenuation of all 3 coronary arteries was also significantly higher in patients with plaque rupture than in plaque erosion, indicating a higher level of inflammation (?67.9 ± 5.7 HU vs ?69.9 ± 6.8 HU; P = 0.030). In multivariable analysis, plaque rupture was significantly associated with high PCAT attenuation.ConclusionsPCAT attenuation in culprit plaque, culprit vessel, and all 3 coronary arteries was higher in plaque rupture than in plaque erosion. The results suggest that pancoronary inflammation plays a more significant role in plaque rupture than in plaque erosion. (Massachusetts General Hospital and Tsuchiura Kyodo General Hospital Coronary Imaging Collaboration; NCT04523194)     

Rotational Atherectomy or Balloon-Based Techniques to Prepare Severely Calcified Coronary Lesions

BackgroundThe comparative efficacy of percutaneous techniques for the preparation of calcified lesions before stenting remains poorly studied.ObjectivesThis study sought to compare the performance of up-front rotational atherectomy (RA) or balloon-based techniques before drug-eluting stent implantation in severely calcified coronary lesions as assessed by angiography and optical coherence tomography (OCT).MethodsPatient-level data from the PREPARE-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) and ISAR-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) randomized trials were pooled. The primary endpoint was stent expansion as assessed by OCT imaging. The secondary endpoints included stent eccentricity, stent asymmetry, angiographic acute lumen gain, strategy success and in-hospital occurrence of cardiac death, target vessel myocardial infarction, and repeat revascularization.ResultsAmong 274 patients originally randomized, 200 participants with available OCT data after lesion preparation with RA (n = 63), a modified balloon (MB, n = 103), or a super high-pressure balloon (n = 34) before stenting were analyzed. The use of RA versus MB or a super high-pressure balloon led to comparable stent expansion (73.2% ± 11.6% vs 70.8% ± 13.6% vs 71.8% ± 12.2%, P = 0.49) and stent asymmetry (P = 0.83). Compared with RA or MB, a super high-pressure balloon was associated with less stent eccentricity (P = 0.03) with a numerically higher acute lumen gain, albeit not significantly different (P = 0.08). Strategy success was more frequent with RA versus MB (P = 0.002) and numerically more frequent with RA versus a super high-pressure balloon (P = 0.06). Clinical outcomes did not differ between groups.ConclusionsIn patients with severely calcified lesions undergoing drug-eluting stent implantation, lesion preparation with RA, MB, or a super high-pressure balloon was associated with comparable stent expansion. A super high-pressure balloon is associated with less stent eccentricity, whereas strategy success is more frequent with RA.     

Clinical Impact of Intravascular Ultrasound–Guided Fluoropolymer-Based Drug-Eluting Stent Implantation for Femoropopliteal Lesions

BackgroundTreatment with a fluoropolymer-based drug-eluting stent (FP-DES has been widely applied to the contemporary femoropopliteal practice with durable outcomes. Nevertheless, the impact of intravascular ultrasound (IVUS) utilization on clinical outcomes after FP-DES implantation has not been determined.ObjectivesThis study aimed to investigate the impact of IVUS on 1-year clinical outcomes after FP-DES) implantation for femoropopliteal lesions in patients with symptomatic peripheral artery disease.MethodsAs a subanalysis of the CAPSICUM (contemporary outcomes after paclitaxel-eluting peripheral stent implantation for symptomatic lower limb ischemia with superficial femoral or proximal popliteal lesion) study, the present investigation analyzed 1,091 patients with symptomatic peripheral artery disease who underwent endovascular therapy with FP-DES for femoropopliteal lesions. One-year clinical outcomes were compared between patients treated with IVUS and those treated without IVUS after propensity score matching. The primary outcome measure was 1-year restenosis. The incidence of aneurysmal degeneration was also assessed.ResultsA total of 843 (77.2%) patients underwent IVUS-guided FP-DES implantation. After propensity score matching, the 1-year restenosis was not significantly different between the groups (11.5% [95% CI: 9.1%-14.0%] vs 15.5% [95% CI: 10.9%-20.1%]; P = 0.22). The frequency of aneurysmal degeneration at 1 year was significantly higher in the IVUS group than in the non-IVUS group (19.8% [95% CI: 16.3%-23.4%] vs 7.1% [95% CI: 3.3%-11.0%]; P < 0.001). IVUS use was associated with a lower restenosis risk in patients with chronic total occlusion but not in those without (P for interaction = 0.044).ConclusionsThe present study revealed that 1-year restenosis risk was not significantly different between the 2 groups, whereas the incidence of aneurysmal degeneration was significantly higher in the IVUS group.     

Impact of Intravascular Ultrasound on Long-Term Clinical Outcomes in Patients With Acute Myocardial Infarction

ObjectivesThe aim of this study was to examine the impact of intravascular ultrasound (IVUS)–guided percutaneous coronary intervention (PCI) on long-term clinical outcomes in patients with acute myocardial infarction (AMI).BackgroundIVUS-guided PCI has been associated with improved cardiovascular outcomes. However, the beneficial effect of IVUS-guided PCI in patients with AMI in the drug-eluting stent era remains unclear.MethodsPatients who underwent PCI with drug-eluting stents were selected from 10,719 patients enrolled in a multicenter AMI registry. The included patients were classified into 2 groups according to the use or nonuse of IVUS. The primary outcome was a composite of major adverse cardiovascular events (MACE), including cardiovascular death, myocardial infarction, and target lesion revascularization, during long-term follow-up.ResultsA total of 9,846 patients were treated with IVUS-guided PCI (n = 2,032) or angiography-guided PCI (n = 7,814). IVUS-guided PCI was associated with reduced MACE (HR: 0.779; 95% CI: 0.689-0.880; P < 0.001). The results were consistent after multivariable regression and propensity score matching. One-year landmark analysis showed a lower risk for MACE within 1 year (HR: 0.766; 95% CI: 0650-0.903; P = 0.002) and beyond 1 year (HR: 0.796; 95% CI: 0663-0.956; P = 0.014) after index PCI.ConclusionsThe use of IVUS was associated with better long-term cardiovascular outcomes. The clinical benefit of IVUS was maintained both within and beyond 1 year after index PCI. The use of IVUS in PCI should be considered for patients with AMI.     

Intravascular Lithotripsy for Treatment of Calcified Coronary Lesions: Patient-Level Pooled Analysis of the Disrupt CAD Studies

ObjectivesThe aim of this pooled analysis was to assess the cumulative safety and effectiveness of coronary intravascular lithotripsy (IVL).BackgroundThe clinical outcomes of IVL to optimize target lesion preparation in severely calcified de novo coronary stenoses have been examined in 4 prospective studies (Disrupt CAD I [NCT02650128], Disrupt CAD II [NCT03328949], Disrupt CAD III [NCT03595176], and Disrupt CAD IV [NCT04151628]).MethodsPatient data were pooled from the Disrupt CAD studies, which shared uniform study criteria, endpoint definitions and adjudication, and procedural follow-up. The primary safety endpoint was freedom from major adverse cardiovascular events (composite of cardiac death, all myocardial infarction, or target vessel revascularization) at 30 days. The primary effectiveness endpoint was procedural success, defined as stent delivery with a residual stenosis ≤30% by quantitative coronary angiography without in-hospital major adverse cardiovascular events. Secondary outcomes included serious angiographic complications, target lesion failure, cardiac death, and stent thrombosis at 30 days.ResultsBetween December 2015 and April 2020, 628 patients were enrolled at 72 sites from 12 countries. Presence of severe calcification was confirmed in 97.0% of target lesions with an average calcified segment length of 41.5 ± 20.0 mm. The primary safety and effectiveness endpoints were achieved in 92.7% and 92.4% of patients, respectively. At 30 days, the rates of target lesion failure, cardiac death, and stent thrombosis were 7.2%, 0.5%, and 0.8%. Rates of post-IVL and final serious angiographic complications were 2.1% and 0.3%, with no IVL-associated perforations, abrupt closure, or episodes of no reflow.ConclusionsIn the largest cohort of patients treated with coronary IVL assessed to date, coronary IVL safely facilitated successful stent implantation in severely calcified coronary lesions with a high rate of procedural success.     

Improved 3-Year Cardiac Survival After IVUS–Guided Long DES Implantation: A Patient-Level Analysis From 2 Randomized Trials

ObjectivesThe present study aimed to evaluate long-term cardiac survival benefit for intravascular ultrasound (IVUS)- versus angiography-guided long drug-eluting stent (DES) implantation.BackgroundAlthough the long-term benefit of IVUS guidance for DES implantation has been reported from recent randomized trials, this benefit was primarily driven by the reduction in repeat revascularization. Thus, it remains uncertain whether IVUS guidance improved survival during long-term follow-up.MethodsWe pooled the data of 2 randomized trials (IVUS-XPL [Impact of Intravascular Ultrasound Guidance on the Outcomes of Xience Prime Stents in Long Lesions] and ULTIMATE [Intravascular Ultrasound Guided Drug Eluting Stents Implantation in All-Comers Coronary Lesions]) and compared IVUS guidance versus angiography guidance in 2,577 patients with long lesions treated with an implanted stent length ≥28 mm. The primary end point was cardiac death at 3 years.ResultsA 3-year clinical follow-up was completed in 96%. The primary end point of cardiac death occurred in 12 patients (1.0%) in the IVUS-guided group vs 28 patients (2.2%) in the angiography-guided group (HR: 0.43; 95% CI: 0.22-0.84; P = 0.011). In addition, target lesion–related myocardial infarction occurred in 3 patients (0.2%) in the IVUS-guided group and in 9 patients (0.7%) in the angiography-guided group (HR: 0.33; 95% CI: 0.09-1.22; P = 0.081), stent thrombosis developed in 3 patients (0.2%) in the IVUS-guided group and 9 patients (0.7%) in the angiography-guided group (HR: 0.33; 95% CI: 0.09-1.23; P = 0.082), and ischemia-driven target lesion revascularization was observed in 47 patients (3.8%) in the IVUS-guided group and 80 patients (6.5%) in the angiography-guided group (HR: 0.57; 95% CI: 0.40-0.82; P = 0.002).ConclusionsIn this post hoc pooled patient-level analysis, the use of IVUS-guided long DES implantation compared with angiography-guided stent implantation improved long-term patient cardiac survival.     

Shear Stress Estimated by Quantitative Coronary Angiography Predicts Plaques Prone to Progress and Cause Events

ObjectivesThis study examined the value of endothelial shear stress (ESS) estimated in 3-dimensional quantitative coronary angiography (3D-QCA) models in detecting plaques that are likely to progress and cause events.BackgroundCumulative evidence has shown that plaque characteristics and ESS derived from intravascular ultrasound (IVUS)−based reconstructions enable prediction of lesions that will cause cardiovascular events. However, the prognostic value of ESS estimated by 3D-QCA in nonflow limiting lesions is yet unclear.MethodsThis study analyzed baseline virtual histology (VH)-IVUS and angiographic data from 28 lipid-rich lesions (i.e., fibroatheromas) that caused major adverse cardiovascular events or required revascularization (MACE-R) at 5-year follow-up and 119 lipid-rich plaques from a control group that remained quiescent. The segments studied by VH-IVUS at baseline were reconstructed using 3D-QCA software. In the obtained geometries, blood flow simulation was performed, and the pressure gradient across the lipid-rich plaque and the mean ESS values in 3-mm segments were estimated. The additive value of these hemodynamic indexes in predicting MACE-R beyond plaque characteristics was examined.ResultsMACE-R lesions were longer, had smaller minimum lumen area, increased plaque burden (PB), were exposed to higher ESS, and exhibited a higher pressure gradient. In multivariable analysis, PB (hazard ratio: 1.08; p = 0.004) and the maximum 3-mm ESS value (hazard ratio: 1.11; p = 0.001) were independent predictors of MACE-R. Lesions exposed to high ESS (>4.95 Pa) with a high-risk anatomy (minimal lumen area <4 mm² and PB >70%) had a higher MACE-R rate (53.8%) than those with a low-risk anatomy exposed to high ESS (31.6%) or those exposed to low ESS who had high- (20.0%) or low-risk anatomy (7.1%; p < 0.001).ConclusionsIn the present study, 3D-QCA-derived local hemodynamic variables provided useful prognostic information, and, in combination with lesion anatomy, enabled more accurate identification of MACE-R lesions.