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

Unravelling the progress and potential of drug-eluting stents and drug-coated balloons in cardiological insurgencies

AIM

Coronary artery disease (CAD) is the leading cause of mortality. Though percutaneous transluminal angioplasty followed by stenting is still the default treatment of choice for revascularization of obstructive CAD, the high rate of restenosis compromises the outcomes of endovascular procedures. To overcome restenosis, drug-eluting stents (DES) and drug-coated balloons (DCB) are designed that release antiproliferative drugs like sirolimus, paclitaxel, everolimus, etc., over time to inhibit cell growth and proliferation. Our review aims to summarize the challenges and progress of DES/DCBs in clinical settings.

MATERIAL AND METHODS

The comprehensive review, search and selection encompasses in relevant articles through Google Scholar, Springer online, Cochrane library and PubMed that includes research articles, reviews, letters and communications, various viewpoints, meta-analyses, randomized trials and quasi-randomized trials. Several preclinical and clinical data have been included from National Institutes of Health and clinicaltrials.gov websites.

KEY FINDINGS

Challenges like delayed endothelialization, stent thrombosis (ST), and inflammation was prominent in first-generation DES. Second-generation DES with improved designs and drug coatings enhanced biocompatibility with fewer complications. Gradual absorption of bioresorbable DES over time mitigated long-term issues associated with permanent implants. Polymer-free DES addressed the inflammation concerns but still, they leave behind metallic stents in the vasculature. As an alternative therapeutic strategy, DCB were developed to minimize inflammation in the vessel. Although both DES and DCBs have shown considerable progress, challenges persist.

SIGNIFICANCE

This review illustrates the advancements in the designs, preparation technologies, biodegradable materials, and drugs used as well as challenges associated with DES and DCBs in clinical settings.

BOOM: A novel bifurcation stent technique using optical coherence tomography co-registration

BACKGROUND/PURPOSE

Bifurcation lesions comprise 20 % of percutaneous coronary interventions (PCI) and are associated with worse long-term outcomes. With an increasing percentage of patients presenting with complex anatomy, including bifurcation disease, there is a need for treatment strategies to optimize PCI outcomes.

METHODS/MATERIALS

We retrospectively analyzed 48 patients undergoing OCT guided bifurcation PCI using the 'Bifurcation and Ostial OCT Mapping' (BOOM) technique. The primary efficacy variable studied was stent precision following deployment, defined as the distance of the most proximal stent strut from the true ostium of the target vessel. Additionally, targeted follow-up occurred by phone at 6- and 12-months post procedure, where the frequency of myocardial infarction, target lesion revascularization, target vessel and non-target vessel revascularization, and mortality were collected.

RESULTS

A total of 40 (83.3 %) had an ostial lesion that required treatment while the remaining patients had true bifurcation disease. Most target lesions were in either the LAD or its branches (29 lesions (60.3 %)). With respect to stent positioning, the median absolute geographic miss, (i.e., stent protrusion into the main branch or lack of complete ostial stent coverage), was 0.75 mm. At 6 months, one patient required target lesion revascularization with no additional patients at 12 months.

CONCLUSIONS

BOOM is a safe and simple strategy that can be a useful technique to optimize precise stent placement for ostial and bifurcation lesions.

Use of Artificial Intelligence Including Multimodal Systems to Improve the Management of Cardiovascular Disease

The rising prevalence of cardiovascular disease presents an escalating challenge for current health services, which are grappling with increasing demands. Innovative changes are imperative to sustain the delivery of high-quality patient care. Recent technologic advances have resulted in the emergence of artificial intelligence as a viable solution. Advanced algorithms are now capable of performing complex analysis of large volumes of data rapidly and with exceptional accuracy. Multimodality artificial intelligence systems handle a diverse range of data including images, text, video, and audio. Compared with single-modality systems, multimodal artificial intelligence systems appear to hold promise for enhancing overall performance and enabling smoother integration into existing workflows. Such systems can empower physicians with clinical decision support and enhanced efficiency. Owing to the complexity of the field, however, truly multimodal artificial intelligence is still scarce in the management of cardiovascular disease. This article aims to cover current research, emerging trends, and the future utilisation of artificial intelligence in the management of cardiovascular disease, with a focus on multimodality systems.

Atherosclerotic plaque stabilization and regression: a review of clinical evidence

Atherosclerotic plaque results from a complex interplay between lipid deposition, inflammatory changes, cell migration and arterial wall injury. Over the past two decades, clinical trials utilizing invasive arterial imaging modalities, such as intravascular ultrasonography, have shown that reducing levels of atherogenic lipoproteins, mainly serum LDL-cholesterol (LDL-C), to very low levels can safely reduce overall atherosclerotic plaque burden and favourably modify plaque composition. Classically, this outcome has been achieved with intensive statin therapy. Since 2016, newer and potent lipid-lowering strategies, such as proprotein convertase subtilisin-kexin type 9 inhibition, have shown incremental effects on plaque regression and risk of clinical events. Despite maximal reduction in plasma LDL-C levels, considerable residual cardiovascular risk remains in some patients. Therefore, there is a need to study therapeutic approaches that address residual risk beyond LDL-C reduction to promote plaque stabilization or regression. Contemporary imaging modalities, such as coronary computed tomography angiography, enable non-invasive assessment of the overall atherosclerotic plaque burden as well as of certain local plaque characteristics. This technology could allow further study of plaque stabilization and regression using novel therapeutic approaches. Non-invasive plaque assessment might also offer the potential to guide personalized management strategies if validated for this purpose.

Long-term clinical outcomes of image-guided percutaneous coronary intervention in acute myocardial infarction from the Korea Acute Myocardial Infarction Registry

Imaging modalities for percutaneous coronary intervention (PCI), such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT), have increased in the current PCI era. However, their clinical benefits in acute myocardial infarction (AMI) have not been fully elucidated. This study investigated the long-term outcomes of image-guided PCI in patients with AMI using data from the Korean Acute Myocardial Infarction Registry. A total of 9,271 patients with AMI, who underwent PCI with second-generation drug-eluting stents between November 2011 and December 2015, were retrospectively examined, and target lesion failure (TLF) at 3 years (defined as the composite of cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization) was evaluated. From the registry, 2,134 patients (23.0%) underwent image-guided PCI (IVUS-guided: n = 1,919 [20.6%]; OCT-guided: n = 215 patients [2.3%]). Based on propensity score matching, image-guided PCI was associated with a significant reduction in TLF (hazard ratio: 0.76; 95% confidence interval: 0.59-0.98, p = 0.035). In addition, the TLF incidence in the OCT-guided PCI group was comparable to that in the IVUS-guided PCI group (5.3% vs 4.7%, p = 0.903). Image-guided PCI, including IVUS and OCT, is associated with favorable clinical outcomes in patients with AMI at 3 years post-intervention. Additionally, OCT-guided PCI is not inferior to IVUS-guided PCI in patients with AMI.

Racial/Ethnic, Sex, and Economic Disparities in the Utilization and Outcomes of Intracoronary Imaging

Background

Intracoronary imaging-guided percutaneous coronary intervention (PCI) is associated with improved outcomes compared with angiography-guided PCI. Data on racial/ethnic, sex, and economic disparities in the utilization and outcomes of intracoronary imaging in the United States are scarce.

Methods

We analyzed the National Inpatient Sample (2016-2020) to examine racial/ethnic, sex, and economic differences in the utilization of intracoronary imaging among patients who underwent PCI. Trends, in-hospital mortality, and safety of intracoronary imaging were also assessed.

Results

Among 2,212,595 weighted hospitalizations for PCI, 204,735 (9.2%) included intracoronary imaging. The utilization rate of intracoronary imaging was similar in Black and Hispanic patients compared with White patients (9.8% vs 10.2% vs 10.0%; P = .68) and lower for women compared with men (10.0% vs 10.3%; P = .01) and for patients with low and medium income compared with high income (9.2% vs 10.0% vs 12.5%; P < .01). In multivariable regression analysis, low and medium income were independently associated with lower intracoronary imaging use compared with high income (both P < .01). From 2016 through 2020, the use of intracoronary imaging in PCI increased significantly in all racial/ethnic, sex, and economic groups (all P trend < .01). Among patients who underwent PCI with intracoronary imaging, Black race was associated with higher odds of acute kidney injury compared with White race (adjusted odds ratio, 1.40; 95% CI, 1.25-1.57). In-hospital mortality was similar between different racial/ethnic, sex, and economic groups.

Conclusions

Low and medium income are independently associated with lower intracoronary imaging use in PCI compared with high income. Further studies are needed to identify effective strategies to mitigate economic disparities in intracoronary imaging use.

Invasive electrochemical impedance spectroscopy with phase delay for experimental atherosclerosis phenotyping

Distinguishing quiescent from rupture-prone atherosclerotic lesions has significant translational and clinical implications. Electrochemical impedance spectroscopy (EIS) characterizes biological tissues by assessing impedance and phase delay responses to alternating current at multiple frequencies. We evaluated invasive 6-point stretchable EIS sensors over a spectrum of experimental atherosclerosis and compared results with intravascular ultrasound (IVUS), molecular positron emission tomography (PET) imaging, and histology. Male New Zealand White rabbits (n = 16) were placed on a high-fat diet, with or without endothelial denudation via balloon injury of the infrarenal abdominal aorta. Rabbits underwent in vivo micro-PET imaging of the abdominal aorta with 68Ga-DOTATATE, 18F-NaF, and 18F-FDG, followed by invasive interrogation via IVUS and EIS. Background signal-corrected values of impedance and phase delay were determined. Abdominal aortic samples were collected for histology. Analyses were performed blindly. EIS impedance was associated with markers of plaque activity including macrophage infiltration (r = .813, p = .008) and macrophage/smooth muscle cell (SMC) ratio (r = .813, p = .026). Moreover, EIS phase delay correlated with anatomic markers of plaque burden, namely intima/media ratio (r = .883, p = .004) and %stenosis (r = .901, p = .002), similar to IVUS. 68Ga-DOTATATE correlated with intimal macrophage infiltration (r = .861, p = .003) and macrophage/SMC ratio (r = .831, p = .021), 18F-NaF with SMC infiltration (r = -.842, p = .018), and 18F-FDG correlated with macrophage/SMC ratio (r = .787, p = .036). EIS with phase delay integrates key atherosclerosis features that otherwise require multiple complementary invasive and non-invasive imaging approaches to capture. These findings indicate the potential of invasive EIS to comprehensively evaluate human coronary artery disease.

Optical coherence tomography-guided vs. intravascular ultrasound-guided percutaneous coronary intervention: a systematic review and meta-analysis of randomized controlled trials

Background

Optical coherence tomography (OCT) and intravascular ultrasound (IVUS) are superior to coronary angiography for guiding percutaneous coronary intervention (PCI). However, whether one technique is superior to the other is inconclusive.

Methods

We searched PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception to November 2023 for randomized controlled trials (RCTs) comparing OCT and IVUS in patients undergoing PCI. RevMan 5.4 was used to pool outcomes with risk ratio (RR) as the effect measure.

Results

Six RCTs (4,402 patients) were included in this meta-analysis. There was no significant difference between the OCT- and IVUS-guided PCI groups in the risk of major adverse cardiovascular events (RR 0.87, 95% CI: 0.65, 1.16; I2 = 0%) and cardiac mortality (RR 0.73, 95% CI: 0.24, 2.21; I2 = 0%). The results were consistent across the subgroups of the presence or absence of left main disease (P interaction >0.1). There were no significant differences between OCT and IVUS in the risk of target lesion revascularization (RR 0.78, 95% CI: 0.47, 1.30; I2 = 0%), target vessel revascularization (RR 1.06, 95% CI: 0.69, 1.62; I2 = 0%), target-vessel myocardial infarction (RR 0.79, 95% CI: 0.40, 1.53; I2 = 0%), stent thrombosis (RR 0.59, 95% CI: 0.12, 2.97; I2 = 0%), and all-cause mortality (RR 1.01, 95% CI: 0.53, 1.90; I2 = 0%).

Conclusions

Our meta-analysis demonstrated similar clinical outcomes in OCT- and IVUS-guided PCI. New large-scale multicenter RCTs with long-term follow-up are required to confirm or refute our findings and provide more reliable results.

Systematic Review Registration

PROSPERO, identifier, CRD42023486933.

One-Month Dual Antiplatelet Therapy Followed by P2Y12 Inhibitor Monotherapy After Biodegradable Polymer Drug-Eluting Stent Implantation - The REIWA Region-Wide Registry

BACKGROUND

The safety and feasibility of using 1-month dual antiplatelet therapy (DAPT) followed by P2Y12inhibitor monotherapy for patients after percutaneous coronary intervention (PCI) with thin-strut biodegradable polymer drug-eluting stents (BP-DES) in daily clinical practice remain uncertain.

METHODS AND RESULTS

The REIWA region-wide registry is a prospective study conducted in 1 PCI center and 9 local hospitals in northern Japan. A total of 1,202 patients who successfully underwent final PCI using BP-DES (Synergy: n=400; Ultimaster: n=401; Orsiro: n=401), were enrolled in the registry, and received 1-month DAPT followed by P2Y12inhibitor (prasugrel 3.75 mg/day or clopidogrel 75 mg/day) monotherapy. The primary endpoint was a composite of cardiovascular and bleeding events at 12 months, including cardiovascular death, myocardial infarction (MI), definite stent thrombosis (ST), ischemic or hemorrhagic stroke, and Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding. Based on the results of a previous study, we set the performance goal at 5.0%. Over the 1-year follow-up, the primary endpoint occurred in 3.08% of patients, which was lower than the predefined performance goal (Pnon-inferiority<0.0001). Notably, definite ST occurred in only 1 patient (0.08%) within 1 year (at 258 days). No differences were observed in the primary endpoint between stent types.

CONCLUSIONS

The REIWA region-wide registry suggests that 1-month DAPT followed by P2Y12inhibitor monotherapy is safe and feasible for Japanese patients with BP-DES.

Intravascular imaging-guided percutaneous coronary intervention in patients with acute myocardial infarction and cardiogenic shock

INTRODUCTION AND OBJECTIVES

There are no clinical data on the efficacy of intravascular imaging-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI in patients with acute myocardial infarction (AMI) and cardiogenic shock. The current study sought to evaluate the impact of intravascular imaging-guided PCI in patients with AMI and cardiogenic shock.

METHODS

Among a total of 28 732 patients from the nationwide pooled registry of KAMIR-NIH (November, 2011 to December, 2015) and KAMIR-V (January, 2016 to June, 2020), we selected a total of 1833 patients (6.4%) with AMI and cardiogenic shock who underwent PCI of the culprit vessel. The primary endpoint was major adverse cardiovascular events (MACE) at 1 year, a composite of cardiac death, myocardial infarction, repeat revascularization, and definite or probable stent thrombosis.

RESULTS

Among the study population, 375 patients (20.5%) underwent intravascular imaging-guided PCI and 1458 patients (79.5%) underwent angiography-guided PCI. Intravascular imaging-guided PCI was associated with a significantly lower risk of 1-year MACE than angiography-guided PCI (19.5% vs 28.2%; HR, 0.59; 95%CI, 0.45-0.77; P<.001), mainly driven by a lower risk of cardiac death (13.7% vs 24.0%; adjusted HR, 0.53; 95%CI, 0.39-0.72; P<.001). These results were consistent in propensity score matching (HR, 0.68; 95%CI, 0.46-0.99), inverse probability weighting (HR, 0.61; 95%CI, 0.45-0.83), and Bayesian analysis (Odds ratio, 0.66, 95% credible interval, 0.49-0.88).

CONCLUSIONS

In AMI patients with cardiogenic shock, intravascular imaging-guided PCI was associated with a lower risk of MACE at 1-year than angiography-guided PCI, mainly driven by the lower risk of cardiac death.

Practice differences and knowledge gaps in complex and high-risk interventions between Japan and the USA: A case-based discussion

Advances in percutaneous coronary intervention (PCI) devices and techniques have expanded the pool of eligible patients for revascularization, including those with comorbidities, reduced left ventricular function, or anatomical complexity (defined as CHIP: complex and high-risk interventions in indicated patients). CHIP interventions are typically performed by selected operators who specialize in complex PCI. This review presents two cases performed in the USA, to discuss the similarities and differences in practice patterns between CHIP operators in Japan and the USA. The first case involves a 58-year-old male presenting with myocardial infarction and cardiogenic shock, and the second case involves a 51-year-old female with a history of coronary artery bypass grafting presenting with a chronic total occlusion and PCI complicated by vessel perforation. The discussion focuses on appropriate patient selection, the role of the heart team approach for decision-making, the use of hemodynamic support devices, and other relevant factors. By comparing practices in Japan and the USA, this review highlights opportunities for knowledge exchange and potential areas for improving patient outcomes.

Diagnostic performance of ultrasonic flow ratio versus quantitative flow ratio for assessment of coronary stenosis

BACKGROUND

Ultrasonic flow ratio (UFR) is a novel intravascular ultrasound (IVUS)-derived modality for fast computation of fractional flow reserve (FFR) without pressure wires and adenosine.

AIMS

This study was sought to compare the diagnostic performance of UFR and quantitative flow ratio (QFR), using FFR as the reference standard.

METHODS

This is a retrospective study enrolling consecutive patients with intermediate coronary artery lesions (diameter stenosis of 30%-90% by visual estimation) for IVUS and FFR measurement. UFR and QFR were performed offline in a core-lab by independent analysts blinded to FFR.

RESULTS

From December 2022 to May 2023, a total of 78 eligible patients were enrolled. IVUS and FFR measurements were successfully conducted in 104 vessels, finally 98 vessels with both FFR, UFR and QFR evaluation were analyzed. Mean FFR was 0.79 ± 0.12. UFR showed a strong correlation with FFR similar to QFR (r = 0.83 vs. 0.82, p = 0.795). Diagnostic accuracy of UFR was non-inferior to QFR (94% [89%-97%] versus 90% [84%-94%], p = 0.113). Sensitivity and specificity in identifying hemodynamically significant stenosis were comparable between UFR and QFR (sensitivity: 89% [79%-96%] versus 85% [74%-92%], p = 0.453; specificity: 97% [91%-99%] versus 95% [88%-99%], p = 0.625). The area under curve for UFR was 0.95 [0.90-0.98], non-inferior to QFR (difference = 0.021, p = 0.293), and significantly higher than minimum lumen area (MLA; difference = 0.13, p < 0.001). Diagnostic accuracy of UFR and QFR was not statically different in bifurcation nor non-bifurcation lesions.

CONCLUSIONS

UFR showed excellent concordance with FFR, non-inferior to QFR, superior to MLA. UFR provides a potentiality for the integration of physiological assessment and intravascular imaging in clinical practice.

Cost-Effectiveness of Intravascular Imaging-Guided Complex PCI: Prespecified Analysis of RENOVATE-COMPLEX-PCI Trial

BACKGROUND

Although clinical benefits of intravascular imaging-guided percutaneous coronary intervention (PCI) in patients with complex coronary artery lesions have been observed in previous trials, the cost-effectiveness of this strategy is uncertain.

METHODS

RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance vs Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) was conducted in Korea between May 2018 and May 2021. This prespecified cost-effectiveness substudy was conducted using Markov model that simulated 3 states: (1) post-PCI, (2) spontaneous myocardial infarction, and (3) death. A simulated cohort was derived from the intention-to-treat population, and input parameters were extracted from either the trial data or previous publications. Cost-effectiveness was evaluated using time horizon of 3 years (within trial) and lifetime. The primary outcome was incremental cost-effectiveness ratio (ICER), an indicator of incremental cost on additional quality-adjusted life years (QALYs) gained, in intravascular imaging-guided PCI compared with angiography-guided PCI. The current analysis was performed using the Korean health care sector perspective with reporting the results in US dollar (1200 Korean Won, ₩=1 dollar, $). Willingness to pay threshold was $35 000 per QALY gained.

RESULTS

A total of 1639 patients were included in the trial. During 3-year follow-up, medical costs ($8661 versus $7236; incremental cost, $1426) and QALY (2.34 versus 2.31; incremental QALY, 0.025) were both higher in intravascular imaging-guided PCI than angiography-guided PCI, resulting incremental cost-effectiveness ratio of $57 040 per QALY gained within trial data. Conversely, lifetime simulation showed total cumulative medical cost was reversed between the 2 groups ($40 455 versus $49 519; incremental cost, -$9063) with consistently higher QALY (8.24 versus 7.89; incremental QALY, 0.910) in intravascular imaging-guided PCI than angiography-guided PCI, resulting in a dominant incremental cost-effectiveness ratio. Consistently, 70% of probabilistic iterations showed cost-effectiveness of intravascular imaging-guided PCI in probabilistic sensitivity analysis.

CONCLUSIONS

The current cost-effectiveness analysis suggests that imaging-guided PCI is more cost-effective than angiography-guided PCI by reducing medical cost and increasing quality-of-life in complex coronary artery lesions in long-term follow-up.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Non-ablative Erbium (YAG) and Neodymium (YAG) Laser Treatment for Anal Incontinence and Vaginal Atrophy: A Case Study

In this case study, a 68-year-old woman with anal incontinence (AI) and vaginal atrophy (VVA), who did not respond to traditional treatments such as pelvic floor exercises or hormone therapy, underwent three sessions of laser treatment using RenovaLase (SP Dynamis; Fotona d.o.o., Ljubljana, Slovenia), which employs non-ablative Erbium:YAG and Neodymium:YAG lasers. Significant improvements were observed in the VVA symptoms, with AI being resolved. The Vaginal Health Index Score increased from 7 points at the initial assessment to 18 points at 12 months after treatment. Similarly, the Cleveland Clinic Florida Fecal Incontinence Score and St. Mark's Incontinence Score, initially at 4 points each, improved to 0 points, indicating resolution of incontinence symptoms. MRI results demonstrated vascular enhancement and growth in the anal sphincter, with the thickness of the internal anal sphincter slightly increasing from initial measurements to a maximum of 0.36 cm, and improvements in resting and squeeze pressures from 42 mmHg to 110 mmHg, respectively. These findings underscore the effectiveness of RenovaLase® laser treatment for VVA and AI symptoms, offering a novel option for pelvic floor health management in postmenopausal women, especially those resistant to the use of artificial devices for anal improvement. In the environment of hormonal decline after menopause, the atrophy of pelvic vessels leads to reduced blood flow. This situation, where a noticeable lack of blood flow occurs during pretreatment of the pelvic vessels, is addressed by laser treatment. This phenomenon has been named "re-canalization." This case suggests the potential of this therapy as an alternative for patients resistant to conventional methods involving the insertion of devices into the anus to improve fecal incontinence. Further research is needed to explore its potential benefits.

Segmentation of anatomical layers and imaging artifacts in intravascular polarization sensitive optical coherence tomography using attending physician and boundary cardinality losses

Intravascular ultrasound and optical coherence tomography are widely available for assessing coronary stenoses and provide critical information to optimize percutaneous coronary intervention. Intravascular polarization-sensitive optical coherence tomography (PS-OCT) measures the polarization state of the light scattered by the vessel wall in addition to conventional cross-sectional images of subsurface microstructure. This affords reconstruction of tissue polarization properties and reveals improved contrast between the layers of the vessel wall along with insight into collagen and smooth muscle content. Here, we propose a convolutional neural network model, optimized using two new loss terms (Boundary Cardinality and Attending Physician), that takes advantage of the additional polarization contrast and classifies the lumen, intima, and media layers in addition to guidewire and plaque shadows. Our model segments the media boundaries through fibrotic plaques and continues to estimate the outer media boundary behind shadows of lipid-rich plaques. We demonstrate that our multi-class classification model outperforms existing methods that exclusively use conventional OCT data, predominantly segment the lumen, and consider subsurface layers at most in regions of minimal disease. Segmentation of all anatomical layers throughout diseased vessels may facilitate stent sizing and will enable automated characterization of plaque polarization properties for investigation of the natural history and significance of coronary atheromas.

A non-interventional cardiologist's guide to coronary chronic total occlusions

Coronary chronic total occlusions (CTO) are present in up to one-third of patients with coronary artery disease (CAD). It is thus essential for all clinical cardiologists to possess a basic awareness and understanding of CTOs, including optimal evaluation and management. While percutaneous coronary intervention (PCI) for CTO lesions has many similarities to non-CTO PCI, there are important considerations pertaining to pre-procedural evaluation, interventional techniques, procedural complications, and post-procedure management and follow-up unique to patients undergoing this highly specialized intervention. Distinct from other existing topical reviews, the current manuscript focuses on key knowledge relevant to non-interventional cardiologists.

Intravascular ultrasound-guided versus angiography-guided percutaneous coronary intervention in unprotected left main coronary artery disease: A systematic review

BACKGROUND

Significant unprotected left main coronary artery (ULMCA) disease is encountered in approximately 5 % of patients undergoing diagnostic coronary angiography. Intravascular ultrasound (IVUS) overcomes many of the known limitations of angiography and improves outcomes of patients undergoing percutaneous coronary interventions (PCI) in stable or complex coronary artery disease. The aim of this systematic review is to evaluate the evidence on IVUS-guidance versus angiography-guidance in ULMCA PCI, highlighting the chronological frequencies of event rates in line with the maturation of PCI technique and devices over time.

METHODS

A comprehensive systematic search in Medline was performed to identify all studies that had assessed the effect of IVUS-guided versus angiography-guided ULMCA PCI on various primary and secondary endpoints.

RESULTS

Seventeen studies (2 randomized, 10 non-randomized and 5 meta-analyses) were included in this systematic review.

CONCLUSIONS

This systematic review on IVUS-guided versus angiography-guided PCI in patients with significant ULMCA disease strongly supports the hypothesis that IVUS-guided PCI is associated with a significant reduction in major adverse cardiac events composites, all-cause death, cardiac death, myocardial infarction and stent thrombosis. Ongoing, adequately powered trials will contribute significantly to the level of evidence.

Guiding Intervention for Complex Coronary Lesions by Optical Coherence Tomography or Intravascular Ultrasound

BACKGROUND

Optical coherence tomography (OCT) and intravascular ultrasound (IVUS) have shown comparable outcomes in guiding percutaneous coronary intervention (PCI). However, their comparative effectiveness in complex coronary artery lesions remains unclear.

OBJECTIVES

This study compared the effectiveness and safety of OCT-guided vs IVUS-guided PCI for complex coronary artery lesions.

METHODS

This was a prespecified, main subgroup analysis of complex coronary artery lesions in the OCTIVUS (Optical Coherence Tomography Versus Intravascular Ultrasound Guided Percutaneous Coronary Intervention) trial, which included unprotected left main disease, bifurcation disease, an aorto-ostial lesion, a chronic total occlusion, a severely calcified lesion, an in-stent restenotic lesion, a diffuse long lesion, or multivessel PCI. The primary endpoint was a composite of death from cardiac causes, target vessel-related myocardial infarction, or ischemia-driven target vessel revascularization.

RESULTS

In 2,008 randomized patients, 1,475 (73.5%) underwent imaging-guided PCI for complex coronary artery lesions; 719 (48.7%) received OCT-guided and 756 (51.3%) IVUS-guided PCI. At a median follow-up of 2.0 years, primary endpoint event had occurred in 47 patients (6.5%) in the OCT-guided group and in 56 patients (7.4%) in the IVUS-guided group (HR: 0.87; 95% CI: 0.59-1.29; P = 0.50). These findings were consistent in adjusted analyses. The incidence of contrast-induced nephropathy was similar between the 2 groups (1.9% vs 1.5%; P = 0.46). The incidence of major procedural complications was lower in the OCT-guided group than in the IVUS-guided group (1.7% vs 3.4%; P = 0.03).

CONCLUSIONS

Among patients with complex coronary artery lesions, OCT-guided PCI showed a similar risk of primary composite event of death from cardiac causes, target vessel-related myocardial infarction, or target vessel revascularization as compared with IVUS-guided PCI. (Optical Coherence Tomography Versus Intravascular Ultrasound Guided Percutaneous Coronary Intervention [OCTIVUS]; NCT03394079).

Drug-Coated Balloon for de-novo Coronary Artery Lesions Exceeding 2.5 mm in Diameter: Optical Coherence Tomography Analysis and Clinical Follow-Up

Objective

To investigate the precise changes in the lumen and lesions, and clinical outcomes after DCB treatment for de-novo coronary lesions exceeding 2.5 mm in diameter through a detailed analysis of OCT.

Methods

This is a prospective study including 53 consecutive patients with 55 de-novo coronary lesions, who underwent DCB angioplasty-only between January 2021 and April 2022. Quantitative coronary angiography (QCA) and OCT were performed before percutaneous coronary interventions (PCI), immediately after PCI, and at 6-9 months follow-up after PCI. Target lesion failure (TLF) was the primary endpoint of the present study. Multivariate logistic regression analysis was performed to identify the predictors or risks for late lumen enlargement (LLE).

Results

A total of 52 patients were successfully treated with DCB. The median follow-up was 7 months, and the incidence of TLF was 7.5%. After the DCB procedure, 43 patients had their scheduled angiographic and OCT examination. QCA demonstrated that the late lumen loss was -0.79 ± 0.28 mm. OCT demonstrated LLE in 79.1% and dissection healing in 65.1% of lesions. After multivariable logistic analysis, type B dissection (odds ratio [OR] 2.92, 95% confidence interval [CI] 1.34-7.41, p = 0.037) was found to be a predictor of LLE, but lipid plaque (OR 0.09, 95% CI 0.01-0.63, p = 0.015) was a risk of LLE.

Conclusion

This is the first and largest prospective study to assess the outcomes of DCB treatment for de-novo coronary lesions exceeding 2.5 mm in diameter and the detection of significant vessel enlargement and dissection healing guide by OCT. DCB could be a novel, safe and effective treatment for de-novo coronary lesions exceeding 2.5 mm in diameter through a detailed analysis of OCT.

Intravascular Imaging-Guided Percutaneous Coronary Intervention Before and After Standardized Optimization Protocols

BACKGROUND

Although benefits of intravascular imaging (IVI) in percutaneous coronary intervention (PCI) have been observed in previous studies, it is not known whether changes in contemporary practice, especially with application of standardized optimization protocols, have improved clinical outcomes.

OBJECTIVES

The authors sought to investigate whether clinical outcomes of IVI-guided PCI are different before and after the application of standardized optimization protocols in using IVI.

METHODS

2,972 patients from an institutional registry (2008-2015, before application of standardized optimization protocols, the past group) and 1,639 patients from a recently published trial (2018-2021 after application of standardized optimization protocols, the present group) were divided into 2 groups according to use of IVI. The primary outcome was 3-year target vessel failure (TVF), a composite of cardiac death, target vessel myocardial infarction, or target vessel revascularization.

RESULTS

Significant reduction of TVF was observed in the IVI-guided PCI group compared with the angiography-guided PCI group (10.0% vs 6.7%; HR: 0.77; 95% CI: 0.61-0.97; P = 0.027), mainly driven by reduced cardiac death or myocardial infarction in both past and present IVI-guided PCI groups. When comparing past IVI and present IVI groups, TVF was significantly lower in the present IVI group (8.5% vs 5.1%; HR: 0.63; 95% CI: 0.42-0.94; P = 0.025), with the difference being driven by reduced target vessel revascularization in the present IVI group. Consistent results were observed in inverse-probability-weighting adjusted analysis.

CONCLUSIONS

IVI-guided PCI improved clinical outcomes more than angiography-guided PCI. In addition, application of standardized optimization protocols when using IVI further improved clinical outcomes after PCI. (Intravascular Imaging- Versus Angiography-Guided Percutaneous Coronary Intervention For Complex Coronary Artery Disease [RENOVATE-COMPLEX-PCI]; NCT03381872; and the institutional cardiovascular catheterization database of Samsung Medical Center: Long-Term Outcomes and Prognostic Factors in Patient Undergoing CABG or PCI; NCT03870815).

Acute left anterior descending artery occlusion after IVUS leading to urgent percutaneous coronary intervention complicated with coronary perforation: Case report

Background

Intravascular ultrasonography (IVUS) has become an important complementary tool in interventional cardiology, both for preprocedural planning and for optimizing the performance of percutaneous coronary intervention (PCI). However, this tool is not free of potential complications, because of that it is essential to be aware of them and their management. Over time, new uses of IVUS have emerged, and it is currently a potential tool for predicting the risk of coronary perforation.

Case report

We present the clinical case of a 51-year-old male patient who was admitted in the context of post-infarction angina. During coronary angiography, the patient presented with two acute complications, one of them associated with IVUS and the other associated with severe coronary calcification that predisposed to coronary perforation. Both complications were successfully treated.

Conclusion

IVUS, although a very useful imaging tool before and during PCI, is not without risk. The overall rate of complications with certain or possible relation to IVUS is 3.9%. Vascular spasm is the most frequent complication and acute vascular occlusion, with the need for emergency coronary artery by-pass grafting, the least frequent. On the other hand, IVUS can predict the risk of developing other complications, such as coronary perforation, by means of the C-CAT sign. Knowledge of the possible complications during PCI and the rapid procedure of the hemodynamic team allows adequate management of these potentially fatal complications.

Enhancing Coronary Intervention Outcomes Using Intravascular Ultrasound: Analysis of Long-Term Benefits in a Japanese Multicenter Registry

Background

Although the use of intravascular ultrasound (IVUS) during percutaneous coronary intervention (PCI) has been shown to improve clinical outcomes, its utilization remains inconsistent. We aimed to assess the association between IVUS-guided PCI and long-term outcomes in Japan, where a high proportion of patients undergo IVUS.

Methods

We analyzed 8721 consecutive patients in a multicenter PCI registry. The primary outcome was a composite of death, acute coronary syndrome, and heart failure requiring admission and coronary artery bypass grafting at 2 years after discharge. The secondary outcome was each component of the primary outcome. We used inverse probability-weighted analysis for adjustment. Subgroup analysis was conducted on patients with complex coronary anatomy (eg, those with bifurcation, chronic total occlusion, type C lesion, left main and those who underwent rotational atherectomy).

Results

Overall, 83.8% of patients underwent IVUS-guided PCI (mean age, 68.3 ± 11.3 years). After adjustments, the IVUS group had significantly lower rates of death and coronary bypass compared to no IVUS group (hazard ratio [HR], 0.73; 95% CI, 0.55-0.96; and HR, 0.62; 95% CI, 0.39-0.98) at 2-year follow-up, although the primary outcome showed only marginal differences (HR, 0.85; 95% CI, 0.71-1.01). In the subgroup analysis of complex coronary anatomy, the use of IVUS was significantly associated with a reduced risk of the primary outcome (HR, 0.72; 95% CI, 0.55-0.93) as well as death, coronary bypass, and heart failure.

Conclusions

IVUS was frequently utilized in our registry and demonstrated potential benefit in reducing mortality and need for coronary bypass surgery, particularly in patients with complex coronary anatomy.

Efficacy of Intravascular Imaging-Guided Drug-Eluting Stent Implantation: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Intravascular imaging (IVI) namely intravascular ultrasound (IVUS) and optical coherence tomography (OCT), presents as a promising imaging modality for drug-eluting stent (DES) implantation compared to the gold-standard conventional two-dimensional angiography. IVI provides detailed information on vessel lumen, lesion length, and degree of calcification. For this purpose, we conducted a meta-analysis by pooling recently conducted randomized control trials (RCTs) to compare IVI with angiography for DES implantation. Scopus and MEDLINE were searched till May 2023 for RCTs comparing IVI with traditional angiography-guided stent implantation in coronary artery disease patients undergoing percutaneous coronary intervention. The primary outcome of interest was target-lesion revascularization (TLR). Secondary outcomes included target vessel revascularization (TVR), all-cause mortality, and major adverse cardiovascular events (MACE). A random-effects meta-analysis with metaregression was performed to derive risk ratios with corresponding 95% CIs from dichotomous data. Fourteen RCTs with a total of 8946 CAD patients (IVI 4751 vs angiography 4195; mean age 61.7 years) and a median follow-up of 15 months (12-24.3) were included. IVI was associated with significantly reduced TLR (RR 0.63 [0.49, 0.79]) vs conventional angiography. Similarly, TVR incidence (RR 0.66 [0.53, 0.83]), and MACE (RR 0.69 [0.58, 0.78]) were also significantly decreased with IVI vs conventional angiography for PCI. However, no significant difference was observed in all-cause mortality between the 2 imaging modalities (RR 0.85 [0.63, 1.15]). Metaregression analysis showed no significant impact of follow-up duration, baseline comorbidities such as hypertension, smoking status, previous MI, and stent length on TLR incidence. IVI was associated with improved clinical outcomes in terms of reduced TLR, TVR, and MACE incidence when compared with traditional angiography in CAD patients for stent implantation.

Prognostic Impact of a Routine Six-Month Exercise Stress Test after Complex Left Main Bifurcation Percutaneous Intervention

The prognostic value of exercise stress test after complex left main (LM) coronary artery bifurcation (LM) stenting has been poorly investigated. To partially fill this gap in knowledge, we retrospectively analyzed the procedural and medical data of consecutive patients referred to our center for complex LM bifurcation disease between January 2008 and May 2018 who were treated using either single- or dual-stenting techniques. The prognostic impact of an exercise stress test, performed 6 months after the coronary intervention, was evaluated in 502 patients (316 males, mean age 70.3 ± 12.8 years, mean Syntax score 31.6 ± 6.3). At follow up after a mean of 37.1 ± 10.8 months (range 22.1-47.3 months), the target lesion failure (TLF) rate was 10.1% while stent thrombosis and cardiovascular mortality were 1.2 and 3.6%, respectively. A positive exercise stress test was detected at 6-month follow up in 42 out of 502 patients (8.4%); the incidence of a significant restenosis was 7.6% (n = 38). Patients with a negative exercise stress test at 6-month follow up had higher freedom from TLF and improved survival compared to those with a positive exercise stress test.

Comparison of Intravascular Imaging, Functional, or Angiographically Guided Coronary Intervention

BACKGROUND

In patients undergoing percutaneous coronary intervention (PCI), it remains unclear whether intravascular imaging guidance or functional guidance is the best strategy to optimize outcomes and if the results are different in patients with vs without acute coronary syndromes (ACS).

OBJECTIVES

The purpose of this study was to evaluate clinical outcomes with imaging-guided PCI or functionally guided PCI when compared with conventional angiography-guided PCI.

METHODS

We searched PUBMED and EMBASE for randomized controlled trials investigating outcomes with intravascular imaging-guided, functionally guided, or angiography-guided PCI. The primary outcome from this network meta-analysis was trial-defined major adverse cardiovascular event (MACE)-a composite of cardiovascular death, myocardial infarction (MI), and target lesion revascularization (TLR). PCI strategies were ranked (best to worst) using P scores.

RESULTS

Our search identified 32 eligible randomized controlled trials and included a total of 22,684 patients. Compared with angiography-guided PCI, intravascular imaging-guided PCI was associated with reduced risk of MACE (relative risk [RR]: 0.72; 95% CI: 0.62-0.82), cardiovascular death (RR: 0.56; 95% CI: 0.42-0.75), MI (RR: 0.81; 95% CI: 0.66-0.99), stent thrombosis (RR: 0.48; 95% CI: 0.31-0.73), and TLR (RR: 0.75; 95% CI: 0.57-0.99). Similarly, when compared with angiography-guided PCI, functionally guided PCI was associated with reduced risk of MACE and MI. Intravascular imaging-guided PCI ranked first for the outcomes of MACE, cardiovascular death, stent thrombosis, and TLR. The results were consistent in the ACS and non-ACS cohorts.

CONCLUSIONS

Angiography-guided PCI had consistently worse outcomes compared with intravascular imaging-guided and functionally guided PCI. Intravascular imaging-guided PCI was the best strategy to reduce the risk of cardiovascular events.

Role of Intravascular Imaging in Complex Percutaneous Coronary Intervention: A Meta-Analysis of Randomized Controlled Trials

Intravascular imaging (IVI) during percutaneous coronary intervention (PCI) has been shown to improve clinical outcomes. However, data is limited in complex PCI and the adoption remains low. We aimed to conduct a meta-analysis of all available randomized controlled trials comparing IVI with conventional angiography in patients who underwent complex PCI. The primary outcomes of interest were major adverse cardiovascular events, all-cause death, cardiovascular death, myocardial infarction, stent thrombosis, target lesion revascularization and target vessel revascularization. Random-effects model was used to calculate pooled risk ratios (RRs) and 95% confidence intervals (CIs). A total of 10 randomized controlled trials comprising 6,368 patients with 3,452 in the IVI group and 2,916 in the angiography group were included. The mean duration of follow up was 2 years, mean age was 65 years and 73% of patients were men. As compared with PCI with routine angiography, the IVI-guided PCI group had significantly lower risks of major adverse cardiovascular events (RR 0.65, 95% CI 0.56 to 0.75, p <0.00001), stent thrombosis (RR 0.57, 95% CI 0.36 to 0.92, p = 0.02), cardiovascular deaths (RR 0.46, 95% CI 0.31 to 0.68, p = 0.0001), target lesion revascularization (RR 0.61, 95% CI 0.48 to 0.78, p <0.0001) and target vessel revascularization (RR 0.62, 95% CI 0.48 to 0.80, p = 0.0003). All-cause deaths and MI were similar in the 2 groups. In conclusion, among patients who underwent complex PCI, IVI reduces adverse events, importantly stent thrombosis and repeat revascularizations, compared with angiography alone guided PCI.

Optical Coherence Tomography in the Evaluation of Suspected Carotid Webs

BACKGROUND

Carotid web (CaW) is a subtype of fibromuscular dysplasia that predominantly involves the intimal layer of the arterial wall and is commonly overlooked as a separate causative entity for recurrent strokes. CaW is defined as a shelf-like lesion at the carotid bulb, although different morphological features have been reported. Optical coherence tomography (OCT) has been described in the literature as a useful microscopic and cross-sectional tomographic imaging tool. This study aimed to evaluate the potential utility of OCT in characterizing the wall structure features of patients with suspected CaW.

METHODS

Retrospective analysis of patients with suspected CaW who underwent digital subtraction angiography (DSA) coupled with OCT of the carotid bulb from 2018 to 2021 in a single comprehensive stroke center.

RESULTS

Sixteen patients were included. The median age was 56 years (IQR 46-61) and 50% were women. OCT corroborated the diagnosis of CaW in 12/16 (75%) cases and ruled it out in 4/16 (25%) patients in whom atherosclerotic disease was demonstrated. Five of the 12 lesions demonstrated a thick fibrotic ridge consistent with CaW but also showed atherosclerotic changes in the vicinity of the carotid bulb (labeled as "CaW+"). In 4/16 (25%) patients, microthrombi adhered to the vessel wall were noted on OCT (inside the CaW pocket or just distal to the web), none of which were observed on CT angiography or DSA.

CONCLUSIONS

OCT may have value as a complementary imaging tool in the investigation of patients with suspected CaW and atypical morphological features. Further studies are warranted.

Multislice computerized tomography coronary angiography can be a comparable tool to intravascular ultrasound in evaluating "true" coronary artery bifurcations

Aim

Coronary bifurcation atherosclerosis depends on its angles, flow, and extensive branching. We investigate the ability of CT coronary angiography (CTCA) to determine atherosclerotic plaque characteristics of "true" bifurcation compared with intravascular ultrasound (IVUS) and the influence on side branch (SB) fate after percutaneous coronary intervention (PCI).

Methods and results

The study included 70 patients with 72 "true" bifurcations. Most of the bifurcations were in the left anterior descending-diagonal (Dg) territory [50 out of 72 (69.4%)]. Longitudinal plaque evaluation at the polygon of confluence [carina and 5 mm proximal and distal in the main branch (MB)] showed that carina side MB and SB plaque had occurred with the lowest incidence with fibro-lipid structure (115 ± 63 HU and 89 ± 73 HU, p < 0.001 for all). Bland-Altman analysis showed a discrepancy in measuring mainly the lumen area between CTCA and IVUS in proximal MB [lumen 5.10, 95% CI (95% confidence interval, 4.53-5.68) mm2, p < 0.001; vessel -1.42, 95% CI (-2.63 to -0.21) mm2, p = 0.023], carina MB [lumen 3.74, 95% CI (3.37-4.10) mm2, p < 0.001; vessel -0.48, 95% CI (-1.45 to 0.48) mm2, p = 0.322], and distal MB [lumen 4.72, 95% CI (4.27-5.18) mm2, p < 0.001; vessel 0.62, 95% CI (-0.53 to 1.77) mm2, p = 0.283]. A significant correlation existed between average plaque density on CTCA with a percentage of calcified plaque on IVUS tissue characterization (proximal r = 0.307/p = 0.024, carina 0.469/0.008, distal 0.339/0.024, minimal lumen diameter 0.318/0.020). Circumferential plaque in the proximal MB segment remained an independent predictor of SB compromise [OR 3.962 (95% CI 1.170-13.418)].

Conclusion

Detection and characterization of atherosclerotic plaque by CTCA in non-left main "true" coronary bifurcations can provide useful information about bifurcation anatomy and plaque distribution that can predict outcomes after provisional stenting, thus guiding the interventional strategy to bifurcation PCI.

Clinical and procedural outcomes of percutaneous coronary intervention for de novo lesions involving the ostial left circumflex coronary artery

BACKGROUND

Percutaneous treatment for ostial left circumflex artery (LCx) lesions is known to be associated with suboptimal results.

AIMS

The present study aims to assess the procedural and long-term clinical outcomes of percutaneous coronary intervention (PCI) for de novo ostial LCx lesions overall and according to the coronary revascularization strategy.

METHODS

Consecutive patients undergoing PCI with second generation drug eluting stents or drug coated balloons for de novo ostial LCx lesions in three high-volume Italian centers between 2012 and 2021 were retrospectively evaluated. The primary endpoint was target-vessel revascularization (TVR) at 2 years. Secondary endpoints included major adverse cardiovascular and cerebrovascular events (MACCE), target lesion revascularization, myocardial infarction, stroke, all-cause death, and repeat revascularization.

RESULTS

A total of 366 patients were included in the analysis with a median follow-up of 901 (IQR: 450-1728) days. 79.5% of the patients were male, 33.6% were diabetic, 49.7% had a previous PCI, and 23.1% a prior surgical revascularization. Very ostial LCx stenting was performed in 34.1%, crossover from left main to LCx in 17.3%, and a two-stent strategy in 48.6% of cases, respectively. In the overall population, the incidence of TVR at 2 years was 19.0% while MACCE rate was 25.7%. No major differences in clinical outcomes were found according to the stenting strategy. Use of intracoronary imaging was associated with fewer MACCE (HR: 0.47, 95% CI: 0.25-1.13, p = 0.01), while the diameter of the stent implanted in the ostial LCx was associated with less TVR (HR: 0.43, 95% CI: 0.25-0.75, p = 0.002).

CONCLUSIONS

Percutaneous revascularization of the ostial LCx is associated with a high rate of TVR, regardless of the stenting strategy. Intracoronary imaging and proper stent sizing may reduce the failure rates.

Intracoronary imaging guided percutaneous coronary intervention outcomes among individuals with cardiogenic shock

BACKGROUND

Limited data exist around the utility of intracoronary imaging (ICI) during percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS) and cardiogenic shock (CS), who are inherently at a high risk of stent thrombosis (ST).

METHODS

All PCI procedures for ACS patients with CS in England and Wales between 2014 and 2020 were retrospectively analysed, stratified into two groups: ICI and angiography-guided groups. Multivariable logistic regression analyses were performed to examine odds ratios (OR) of in-hospital outcomes, including major adverse cardiovascular and cerebrovascular events (MACCE; composite of all-cause mortality, acute stroke/transient ischaemic attack (TIA), and reinfarction) and major bleeding, in the ICI-guided group compared with angiography-guided PCI.

RESULTS

Of 15,738 PCI procedures, 1240(7.9%) were ICI-guided. The rate of ICI use amongst those with CS more than doubled from 2014 (5.7%) to 2020 (13.3%). The ICI-guided group were predominantly younger, males, with a higher proportion of non-ST-elevation ACS and ST. MACCE was significantly lower in the ICI-guided group compared with the angiography-guided group (crude: 29.8% vs. 38.2%, adjusted odds ratio (OR) 0.65 95% confidence interval [CI] 0.56-0.76), driven by lower all-cause mortality (28.6% vs. 37.0%, OR 0.65 95% CI 0.55-0.75). There were no differences in other secondary outcomes between groups.

CONCLUSION

ICI use among CS patients has more than doubled over 6 years but remains significantly under-utilized, with less than 1-in-6 patients in receipt of ICI-guided PCI by 2020. ICI-guided PCI is associated with prognostic benefits in CS patients and should be more frequently utilized to increase their long-term survival.

Optical Coherence Tomography-Guided or Intravascular Ultrasound-Guided Percutaneous Coronary Intervention: The OCTIVUS Randomized Clinical Trial

BACKGROUND

Intravascular imaging-guided percutaneous coronary intervention (PCI) with intravascular ultrasound (IVUS) or optical coherence tomography (OCT) showed superior clinical outcomes compared with angiography-guided PCI. However, the comparative effectiveness of OCT-guided and IVUS-guided PCI regarding clinical outcomes is unknown.

METHODS

In this prospective, multicenter, open-label, pragmatic trial, we randomly assigned 2008 patients with significant coronary artery lesions undergoing PCI in a 1:1 ratio to undergo either an OCT-guided or IVUS-guided PCI. The primary end point was a composite of death from cardiac causes, target vessel-related myocardial infarction, or ischemia-driven target-vessel revascularization at 1 year, which was powered for noninferiority of the OCT group compared with the IVUS group. Safety outcomes were also assessed.

RESULTS

At 1 year, primary end point events occurred in 25 of 1005 patients (Kaplan-Meier estimate, 2.5%) in the OCT group and in 31 of 1003 patients (Kaplan-Meier estimate, 3.1%) in the IVUS group (absolute difference, -0.6 percentage points; upper boundary of one-sided 97.5% CI, 0.97 percentage points; P<0.001 for noninferiority). The incidence of contrast-induced nephropathy was similar (14 patients [1.4%] in the OCT group versus 15 patients [1.5%] in the IVUS group; P=0.85). The incidence of major procedural complications was lower in the OCT group than in the IVUS group (22 [2.2%] versus 37 [3.7%]; P=0.047), although imaging procedure-related complications were not observed.

CONCLUSIONS

In patients with significant coronary artery lesions, OCT-guided PCI was noninferior to IVUS-guided PCI with respect to the incidence of a composite of death from cardiac causes, target vessel-related myocardial infarction, or ischemia-driven target-vessel revascularization at 1 year. The selected study population and lower-than-expected event rates should be considered in interpreting the trial.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique number: NCT03394079.

Determination of Left Main Coronary Artery Stenosis Through Noninvasive Testing to Guide Revascularization in Ischemic Heart Disease

Anatomically severe left main coronary artery (LMCA) stenosis (>50%) remains one of the few groups to benefit from early revascularization in stable ischemic heart disease (SIHD). Identification of these patients through widely available noninvasive testing would decrease the need for additional upfront anatomic testing, lowering the overall cost of healthcare. Patients with SIHD who underwent either percutaneous or surgical revascularization over a 7-year period at our institution were retrospectively analyzed and categorized as having LMCA stenosis versus non-LM stenosis. All preceding noninvasive testing, including resting electrocardiogram, echocardiogram, and functional testing was evaluated and compared between groups using chi-square and t test. In total, 806 patients were evaluated. Of those, 121 were identified as having significant LMCA stenosis with 685 patients in the non-LM cohort. Between LMCA versus non-LM cohorts, there were similar rates of electrocardiogram abnormalities (68.9% vs 70.8%, p >0.05), abnormal echocardiograms (72.7% vs 69.7%, p >0.05), abnormal functional testing (83.3% vs 77.4%, p >0.05), and high-risk imaging findings (5.6% vs 4.8%, p >0.05). More importantly, of those with a complete workup, there were similar rates of normal results between the LMCA (3 of 18, 16.7%) and non-LM stenosis (9 of 189, 4.8%) groups. A comprehensive noninvasive profile of patients with IHD failed to identify or exclude patients with anatomically severe LMCA stenosis, necessitating anatomic assessment.

Outcomes of Intravascular Ultrasound-Guided Percutaneous Coronary Intervention Among Patients With Acute Coronary Syndrome

Intravascular ultrasound (IVUS) use in percutaneous coronary intervention (PCI) improves outcomes. However, data on outcomes of IVUS-guided PCI in patients presenting with acute coronary syndrome (ACS) is scarce. Therefore, we sought to study the utilization rate and outcomes of IVUS-guided PCI in patients with ACS. Using the National Readmission database, we identified all patients with ACS who underwent PCI from 2016 to 2019. We used a 1:1 propensity-matched analysis to compare the outcome of patients with ACS who underwent PCI with and without IVUS. In 1,263,997 patients with ACS, 563,521 (44.6%) underwent PCI without IVUS and 40,095 (3.17%) underwent IVUS-guided PCI. A Propensity scored matched comparison of PCI with and without IVUS showed IVUS-guided PCI was associated with a lower risk of in-hospital mortality (odds ratio 0.74, 95% confidence interval 0.64 to 0.85, p <0.01) compared with PCI without IVUS. The utilization of IVUS increased from 2.64% in 2016 to 4.10% in 2019, p <0.001. In conclusion, IVUS-guided PCI is associated with lower in-hospital mortality in patients with ACS, yet the current utilization of IVUS-guided PCI remains low across the United States.

State-of-art review: intravascular imaging in percutaneous coronary interventions

The history of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) reflects the relentless pursuit of innovation in interventional cardiology. These intravascular imaging technologies have played a pivotal role in our understanding of coronary atherosclerosis, vascular pathology, and the interaction of coronary stents with the vessel wall. Two decades of clinical investigations demonstrating the clinical efficacy and safety of intravascular imaging modalities have established these technologies as staples in the contemporary cardiac catheterization lab's toolbox and earning their place in revascularization clinical practice guidelines. In this comprehensive review, we will delve into the historical evolution, mechanisms, and technical aspects of IVUS and OCT. We will discuss the expanding evidence supporting their use in complex percutaneous coronary interventions, emphasizing their crucial roles in optimizing patient outcomes and ensuring procedural success. Furthermore, we will explore the substantial advances that have propelled these imaging modalities to the forefront of contemporary interventional cardiology. Finally, we will survey the latest developments in the field and explore the promising future directions that have the potential to further revolutionize coronary interventions.

The Usefulness of Intracoronary Imaging in Patients with ST-Segment Elevation Myocardial Infarction

Intracoronary imaging (ICI) modalities, namely intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have shown to be able to reduce major adverse cardiovascular events in patients undergoing percutaneous coronary intervention (PCI). Nevertheless, patients with ST-segment elevation myocardial infarction (STEMI) have been practically excluded from contemporary large randomized controlled trials. The available data are limited and derive mostly from observational studies. Nevertheless, contemporary studies are in favor of ICI utilization in patients who undergo primary PCI. Regarding technical aspects of PCI, ICI has been associated with the implantation of larger stent diameters, higher balloon inflations and lower residual in-stent stenosis post-PCI. OCT, although used significantly less often than IVUS, is a useful tool in the context of myocardial infarction without obstructive coronary artery disease since, due to its high spatial resolution, it can identify the underlying mechanism of STEMI, and, thus, guide therapy. Stent thrombosis (ST) is a rare, albeit a potential lethal, complication that is expressed clinically as STEMI in the vast majority of cases. Use of ICI is encouraged with current guidelines in order to discriminate the mechanism of ST among stent malapposition, underexpansion, uncovered stent struts, edge dissections, ruptured neoatherosclerotic lesions and coronary evaginations. Finally, ICI has been proposed as a tool to facilitate stent deferring during primary PCI based on culprit lesion characteristics.

Percutaneous Treatment of Left Main Disease: A Review of Current Status

Percutaneous treatment of the left main coronary artery is one of the most challenging scenarios in interventional cardiology, due to the large portion of myocardium at risk the technical complexity of treating a complex bifurcation with large branches. Our aim is to provide un updated overview of the current indications for percutaneous treatment of the left main, the different techniques and the rationale underlying the choice for provisional versus upfront two-stent strategies, intravascular imaging and physiology guidance in the management of left main disease, and the role of mechanical support devices in complex high-risk PCI.

Clinical and Procedural Outcomes of IVUS-Guided vs. Angiography-Guided CTO-PCI: A Systematic Review and Meta-Analysis

Chronic total occlusions (CTO) in coronary angiographies present a significant challenge nowadays. Intravascular ultrasound (IVUS) is a valuable tool during CTO-PCI, aiding in planning and achieving procedural success. However, the impact of IVUS on clinical and procedural outcomes in CTO-PCI remains uncertain. This meta-analysis aimed to compare IVUS-guided and angiography-guided approaches in CTO-PCI. The study included five studies and 2320 patients with stable coronary artery disease (CAD) and CTO. The primary outcome of major adverse cardiac events (MACE) did not significantly differ between the groups (p = 0.40). Stent thrombosis was the only secondary clinical outcome that showed a significant difference, favoring the IVUS-guided approach (p = 0.01). Procedural outcomes revealed that IVUS-guided procedures had longer stents, larger diameters, and longer procedure and fluoroscopy times (p = 0.007, p < 0.001, p = 0.03, p = 0.002, respectively). Stent number and contrast volume did not significantly differ between the approaches (p = 0.88 and p = 0.33, respectively). In summary, routine IVUS use did not significantly improve clinical outcomes, except for reducing stent thrombosis. Decisions in CTO-PCI should be individualized based on patient characteristics and supported by a multi-parametric approach.

The Role of Intracoronary Imaging for the Management of Calcified Lesions

Interventional cardiologists in everyday practice are often confronted with calcified coronary lesions indicated for percutaneous transluminal coronary angioplasty (PTCA). PTCA of calcified lesions is associated with diverse technical challenges resulting in suboptimal coronary stenting and adverse long-term clinical outcomes. Angiography itself offers limited information regarding coronary calcification, and the adjuvant use of intracoronary imaging such as intravascular ultrasound (IVUS) and Optical Coherence Tomography (OCT) can guide the treatment of calcified coronary lesions, optimizing the different stages of the procedure. This review offers a description of why, when, and how to use intracoronary imaging for PTCA of calcified coronary lesions in order to obtain the most favorable results. We used the PubMed and Google Scholar databases to search for relevant articles. Keywords were calcified coronary lesions, intracoronary imaging, IVUS, OCT, coronary calcium modification techniques, PTCA, and artificial intelligence in intracoronary imaging. A total of 192 articles were identified. Ninety-one were excluded because of repetitive or non-important information.

Practice Pattern Variation in Adoption of New and Evolving Percutaneous Coronary Intervention Procedures

Objective

Assess factors contributing to variation in the use of new and evolving diagnostic and interventional procedures for percutaneous coronary intervention (PCI).

Background

Evidence-based practices for PCI have the potential to improve outcomes but are variably adopted. Finding possible drivers of PCI procedure-use variability is key for efforts aimed at establishing more uniform practice.

Methods

Veterans Affairs Clinical Assessment, Reporting, and Tracking Program data were used to estimate a proportion of variation attributable to hospital-, operator-, and patient-level factors across (a) radial arterial access, (b) intravascular imaging/optical coherence tomography, and (c) atherectomy for PCI. We used random-effects models with hospital, operator, and patient random effects. Overlap between levels generated cumulative variability estimates greater than 100%.

Results

A total of 445 operators performed 95,391 PCI procedures across 73 hospitals from 2011 to 2018. The rates of all procedures increased over this time. 24.45% of variability in the use of radial access was attributable to the hospital, 53.04% to the operator, and 57.83% to patient-level characteristics. 9.06% of the variability in intravascular imaging use was attributable to the hospital, 43.92% to the operator, and 21.20% to the patient. Lastly, 20.16% of the variability in use of atherectomy was attributed to the hospital, 34.63% to the operator, and 57.50% to the patient.

Conclusions

The use of radial access, intracoronary imaging, and atherectomy is influenced by patient, operator, and hospital factors, but patient and operator-level effects predominate. Efforts to increase the use of evidence-based practices for PCI should consider interventions at these levels.