IVUS-Guided Versus OCT-Guided Coronary Stent Implantation: A Critical Appraisal

Mechanical outcomes of coronary stenting guided by intravascular ultrasound versus optical coherence tomography: A systematic review and meta-analysis with trial sequential analysis of randomized trials

BACKGROUND

Intravascular imaging with intravascular ultrasound (IVUS) or optical coherence tomography (OCT) may guide stent sizing and placement during percutaneous coronary intervention (PCI). We compared IVUS- vs. OCT-guided PCI in terms of mechanical outcomes.

METHODS

PubMed, Embase and Cochrane databases were systematically searched until December 2024 for randomized controlled trials (RCTs) comparing IVUS- vs. OCT-guided PCI. Random-effects models were used to estimate mean differences (MDs) and standard mean differences (SMDs) with 95 % confidence intervals (CIs).

RESULTS

Six RCTs with 2696 patients were included; 1396 (49.6 %) underwent IVUS-guided PCI. The mean age was 65.1 ± 10.2 years. In the pooled analysis, the post-PCI minimum stent area (MSA) was significantly higher with IVUS-guided PCI than with OCT-guided PCI (MD 0.64 mm2; 95 % CI 0.17-1.10; p < 0.01), and post-PCI mean diameter stenosis was significantly lower with IVUS (MD -1.05 %; 95 % CI -1.90 to -0.21; p = 0.01). There were no significant differences between groups in acute lumen gain, stent expansion index, malapposition, tissue protrusion, or edge dissection. In a subgroup analysis, IVUS-guided PCI yielded a greater MSA in studies that did not size vessels by measurement of the external elastic membrane. However, trial sequential analysis suggested that the RCTs to date have not reached the required quantity of information to support definitive conclusions about MSA and mean diameter stenosis.

CONCLUSION

This meta-analysis demonstrated that IVUS-guided PCI was associated with greater MSA and reduced diameter stenosis compared to OCT-guided PCI, with no difference in stent expansion index, more trials are required to confirm this hypothesis.

The PROMISE of Precision Medicine in Myocardial Infarction with Non-Obstructive Coronary Arteries

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a working diagnosis encompassing several pathophysiological mechanisms with specific treatments and different prognoses. Despite the absence of obstructive coronary artery disease, MINOCA has proven to be associated with a significant risk of mortality, angina burden, and socioeconomic costs. However, due to the heterogeneous nature of this clinical condition and the absence of randomized clinical trials, evidence supporting a standardized diagnostic algorithm and the clinical management of these patients is lacking. The PROMISE trial is the first randomized clinical trial evaluating the effectiveness of a precision medicine approach strategy in improving the outcomes and quality of life of patients with MINOCA, offering new insights into personalized treatment strategies. This review article discusses the promise of a precision medicine approach in patients with MINOCA, highlighting the potential innovations and challenges of a personalized medicine strategy in MINOCA.

Effect of Pulsed-Field Ablation on Human Coronary Arteries: A Longitudinal Study With Intracoronary Imaging

BACKGROUND

Pulsed-field ablation (PFA) is known to cause acute coronary spasm. Whether this translates into long-term coronary artery stenosis is unknown.

OBJECTIVES

This study sought to evaluate changes in coronary artery after PFA for atrial flutter.

METHODS

After pulmonary vein isolation with PFA (Farapulse; Boston Scientific), patients undergoing ablation of the mitral isthmus (MI) or cavotricuspid isthmus (CTI) were included. They underwent coronary angiography and optical coherence tomography (OCT) before and immediately after ablation. Bolus intracoronary nitroglycerine was given before and throughout ablation. Three months after ablation, patients underwent repeated OCT.

RESULTS

A total of 21 patients were included. 1 patient did not undergo PFA owing to the incidental finding of a critical coronary lesion in close proximity to the area to be ablated. Another patient defaulted postprocedure imaging follow-up. 19 patients had paired imaging data, in 20 coronary vessels (18 right coronary and 2 left circumflex arteries). At the ablation site, at 3 months, vascular wall area increased by a median of 0.40 mm2 (Q1-Q3: 0.13-0.71 mm2; P < 0.01), or 17.1% (Q1-Q3: 8.6%-31.0%). The median reduction in the luminal area was 0.70 mm2 (Q1-Q3: 0.18-1.30 mm2; P < 0.01), or 10.1% (Q1-Q3: 4.7%-16.2%). These changes were not observed in a predetermined reference site remote from the ablation target.

CONCLUSIONS

PFA of the CTI and MI is associated with acute spasm, and mild narrowing of the coronary arteries at 3 months. Although intracoronary vasodilator therapy may prevent or treat acute spasm, the risk of arterial stenosis remains, calling for heightened vigilance and long-term follow-up.

2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes" incorporates new evidence since the "2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction" and the corresponding "2014 AHA/ACC Guideline for the Management of Patients With Non-ST-Elevation Acute Coronary Syndromes" and the "2015 ACC/AHA/SCAI Focused Update on Primary Percutaneous Coronary Intervention for Patients With ST-Elevation Myocardial Infarction." The "2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes" and the "2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization" retire and replace, respectively, the "2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease."

METHODS

A comprehensive literature search was conducted from July 2023 to April 2024. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Intravascular Imaging-Guided Versus Angiography-Guided Percutaneous Coronary Intervention in Patients With ST-Segment Elevation Myocardial Infarction in the United States

BACKGROUND

The role of Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) is still unclear in patients with STEMI undergoing PCI in the current second-generation DES era.

AIMS

This study aimed to evaluate the trends and outcomes of IVUS-guided PCI in patients with STEMI.

METHODS

We used the National Inpatient Sample (NIS) database from 2016 to 2021. The primary endpoint of this study is all-cause in-hospital mortality. Secondary endpoints include trends of PCI hospitalizations, trends of mortality, length of stay, and cost of hospitalization.

RESULTS

There were data for 819,645 hospitalizations for STEMI, of which 91.2% (n = 74,7860) utilized angiography-guided PCI, 8.4% (n = 68,985) utilized IVUS-guided PCI and 0.3% (n = 2800) utilized OCT-guided PCI. In-hospital mortality for IVUS-guided PCI was 4.6% (n = 3190) versus 6.0% (n = 44,935) for angiography-guided PCI with an adjusted OR 0.75 (0.68-0.81, p < 0.001). In-hospital mortality for OCT-guided PCI was 3.4% (n = 95) versus 6.0% (n = 44,935) for angiography-guided PCI with an adjusted OR 0.67 (0.43-1.06, p = 0.09).

CONCLUSIONS

IVUS/OCT-guidance was increasingly utilized over the years and was associated with a significantly reduced adjusted odds of in-hospital mortality. Large-scale, long-term randomized data are needed to better ascertain where IVUS/OCT may be best utilized for optimization of PCI for STEMI.

A real-world experience with a thin-strut bioresorbable vascular scaffold system: a single-centre study

Background

Despite the significant advancements in interventional cardiology, there is a need for new, metal-free bioresorbable stent systems that preserve the vasomotor function of the treated vessel and decrease the risk of restenosis associated with metal stents and the risk of thrombosis associated with first-generation bioresorbable scaffolds.

Aims

The aim of this study was to assess the safety and efficacy of the MeRes100 bioresorbable scaffold in complex de novo and in-stent restenotic coronary lesions.

Methods

We conducted a retrospective single-centre study that included 86 patients with coronary artery disease who had been implanted with a next-generation MeRes100 sirolimus-eluting bioresorbable vascular scaffold system and followed up to 12 months after the procedure.

Results

The scaffold was successfully delivered to the target lesion with satisfactory stent expansion in 98.84% of cases. Only one patient died, and the in-hospital mortality rate was as low as 1.16% (cardiac death). No cases of major adverse cardiac events, cardiac death, myocardial infarction, ischaemia-driven target lesion revascularisation, or scaffold thrombosis were reported during the follow-up.

Conclusions

Our preliminary data suggest that the thin-strut sirolimus-eluting bioresorbable scaffold appears to be a clinically acceptable, safe, reliable and reproducible strategy to treat both de novo and in-stent restenotic coronary artery lesions. Long-term follow-up of a larger patient population is warranted.

2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes" incorporates new evidence since the "2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction" and the corresponding "2014 AHA/ACC Guideline for the Management of Patients With Non-ST-Elevation Acute Coronary Syndromes" and the "2015 ACC/AHA/SCAI Focused Update on Primary Percutaneous Coronary Intervention for Patients With ST-Elevation Myocardial Infarction." The "2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes" and the "2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization" retire and replace, respectively, the "2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease."

METHODS

A comprehensive literature search was conducted from July 2023 to April 2024. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Discussion on the comparison of Raman spectroscopy and cardiovascular disease-related imaging techniques and the future applications of Raman technology: a systematic review

Cardiovascular disease (CVD) is a major cause of unnatural death worldwide, so timely diagnosis of CVD is crucial for improving patient outcomes. Although the traditional diagnostic tools can locate plaque and observe inner wall of blood vessel structure, they commonly have radioactivity and cannot detect the chemical composition of the plaque accurately. Recently emerging Raman techniques can detect the plaque composition precisely, and have the advantages of being fast, high-resolution and marker-free. This makes Raman have great potential for detecting blood samples, understanding disease conditions, and real-time monitoring. This review summarizes the origin and state-of-art of Raman techniques, including the following aspects: (a) the principle and technical classification of Raman techniques; (b) the applicability of Raman techniques and its comparison with traditional diagnostic tools at different diagnosis targets; (c) the applicability of Raman spectroscopy in advanced CVD. Lastly, we highlight the possible future applications of Raman techniques in CVD diagnosis.

From Mechanisms to Management: Tackling In-Stent Restenosis in the Drug-Eluting Stent Era

PURPOSE OF REVIEW

Drug-eluting stent (DES) technology has greatly enhanced the safety and effectiveness of percutaneous coronary interventions (PCI). The aim of the present paper is to provide a comprehensive review of in-stent restenosis (ISR), focusing on the contemporary DES era, including its incidence, mechanisms, and imaging characterization.

RECENT FINDINGS

Despite the widespread use of DES and numerous improvements, recent clinical data indicate that ISR still occurs in 5-10% of PCI procedures, posing a considerable public health issue. The incidence, morphology, and clinical implications of ISR are determined by a complex interplay of several factors: the patient, stent, procedure, and vessel and lesion-related factors. Advancements in intracoronary imaging have provided greater insight into its patterns and underlying causes. Over time, treatment strategies have evolved, and current guidelines recommend an individualized approach using intracoronary imaging to characterize ISR's underlying substrate.

Intravascular Imaging Predictors Associated With Cardiovascular Events After Complex PCIs

BACKGROUND

Intravascular imaging-guided percutaneous coronary intervention (PCI) has been shown to improve clinical outcomes in patients with complex coronary artery lesions compared with angiography-guided PCI. However, the prognostic impact of suboptimal findings on intravascular imaging such as stent underexpansion, malapposition, or dissection is unclear in the era of contemporary drug-eluting stents.

METHODS

From RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) which compared imaging-guided PCI with angiography-guided PCI in patients with complex lesions, post-PCI intravascular imaging findings, including minimum stent area (MSA), relative stent underexpansion (MSA≤80% of the average reference lumen area), malapposition, or dissection, were assessed in nonleft main target lesions. The primary end point was target lesion failure (TLF), a composite of cardiac death, target lesion-related myocardial infarction, target lesion revascularization, or definite stent thrombosis.

RESULTS

A total of 897 nonleft main lesions from 714 patients undergoing imaging-guided PCI were included. During a median follow-up duration of 2.1 years, the optimal cutoff value of MSA to predict the occurrence of TLF was 5.5 mm2, and MSA<5.5 mm2 was associated with a significantly higher risk of TLF than MSA≥5.5 mm2 (2.2% versus 4.8%; adjusted hazard ratio, 3.09 [95% CI, 1.01-9.50]; P=0.048). Compared with the reference group (MSA≥5.5 mm2 and no suboptimal findings), the subgroup of patients with MSA≥5.5 mm2 and post-PCI intravascular imaging findings of relative stent underexpansion, major malapposition, or major dissection was associated with a numerically increased risk of TLF (0.0% versus 3.2%; P=0.057). Compared with the same reference group, the subgroup of patients with MSA<5.5 mm2 and suboptimal post-PCI intravascular imaging findings was associated with a significantly increased risk of TLF (0.0% versus 4.7%; P=0.017).

CONCLUSIONS

After intravascular imaging-guided PCI with contemporary drug-eluting stents for nonleft main complex lesions, inadequate absolute stent expansion was independently associated with a higher risk of TLF. Suboptimal post-PCI intravascular imaging findings of relative stent underexpansion, major malapposition, and major dissection seem to contribute to the risk of TLF.

REGISTRATION

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

Computed Tomography Angiography in the Catheterization Laboratory: A Guide Towards Optimizing Coronary Interventions

Cardiac computed tomography (CT) has become an essential tool in the pre-procedural planning and optimization of coronary interventions. Its non-invasive nature allows for the detailed visualization of coronary anatomy, including plaque burden, vessel morphology, and the presence of stenosis, aiding in precise decision making for revascularization strategies. Clinicians can assess not only the extent of coronary artery disease but also the functional significance of lesions using techniques like fractional flow reserve (FFR-CT). By providing comprehensive insights into coronary structure and hemodynamics, cardiac CT helps guide personalized treatment plans, ensuring the more accurate selection of patients for percutaneous coronary interventions or coronary artery bypass grafting and potentially improving patient outcomes.

Intravascular Ultrasound-Guided Versus Angiography-Guided Percutaneous Coronary Intervention: A Systematic Review, Meta-Analysis, and Meta-Regression of Randomized Control Trials

BACKGROUND

Intravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) allows better assessment of coronary artery lesion characteristics than angiography alone. This systematic review and meta-analysis aimed to comprehensively synthesize the available evidence regarding the efficacy of IVUS guidance compared to angiography-guided PCI.

METHODS

A comprehensive literature search of major bibliographic databases from inception until April 2024 was conducted to identify randomized control trials (RCTs) comparing IVUS-guided PCI versus angiography-guided PCI. Risk ratios (RR) with their corresponding 95% confidence intervals (CI) were pooled using the random-effects model, with a p < 0.05 considered statistically significant.

RESULTS

Fifteen RCTs were included with 9354 patients undergoing PCI. IVUS-guided PCI was associated with a lower risk of cardiac death [RR 0.49, 95% CI 0.33 to 0.72], major adverse cardiovascular events (MACE) [RR 0.64, 95% CI 0.51 to 0.80], myocardial infarction [RR 0.74, 95% CI 0.59 to 0.94], stent thrombosis [RR 0.48, 95% CI 0.29 to 0.81], target lesion revascularization [RR 0.60, 95% CI 0.48 to 0.75], and target vessel revascularization [RR 0.54, 95% CI 0.43 to 0.69] compared to angiography-guided PCI. IVUS-guided PCI was associated with a nonsignificant trend toward a reduced risk of all-cause mortality [RR 0.82, 95% CI 0.58 to 1.01]. Meta-regression showed a nonsignificant moderating effect of the duration of follow-up, age of patients, diabetes mellitus, and acute coronary syndrome presentation of patients on pooled outcomes.

CONCLUSION

IVUS-guided PCI reduced cardiac death, MACE, myocardial infarction, stent thrombosis, target lesion revascularization, and target vessel revascularization compared to angiography-guided PCI.

Optimal Predilatation Treatment Before Implantation of a Magmaris Bioresorbable Scaffold in Coronary Artery Stenosis: The OPTIMIS Trial

BACKGROUND

Bioresorbable scaffolds (BRS) were developed to overcome limitations related to late stent failures of drug-eluting stents, but lumen reductions over time after implantation of BRS have been reported. This study aimed to investigate if lesion preparation with a scoring balloon compared with a standard noncompliant balloon minimizes lumen reduction after implantation of a Magmaris BRS assessed with optical coherence tomography and intravascular ultrasound.

METHODS

Eighty-two patients with stable angina were randomized in a ratio of 1:1 to lesion preparation with a scoring balloon versus a standard noncompliant balloon before implantation of a Magmaris BRS. The primary end point was minimal lumen area at 6-month follow-up.

RESULTS

Following Magmaris BRS implantation, minimal lumen area (6.4±1.6 versus 6.3±1.5 mm2; P=0.65), mean scaffold area (7.8±1.5 versus 7.5±1.7 mm2; P=0.37), and mean lumen area (8.0±1.6 versus 7.7±2.1 mm2; P=0.41) did not differ significantly in patients with lesions prepared with scoring versus standard noncompliant balloon, respectively. Six-month angiographic follow-up with optical coherence tomography and intravascular ultrasound was available in 74 patients. The primary end point, 6-month minimal lumen area, was significantly larger in lesions prepared with a scoring balloon compared with a standard noncompliant balloon (4.7±1.4 versus 3.9±1.9 mm2; P=0.04), whereas mean lumen area (7.2±1.4 versus 6.8±2.2 mm2; P=0.35) did not differ significantly. Intravascular ultrasound findings showed no difference in mean vessel area at the lesion site from baseline to follow-up in the scoring balloon group (16.8±2.9 versus 17.0±3.6 mm2; P=0.62), whereas mean vessel area (17.1±4.4 versus 15.7±4.9 mm2; P<0.001) was smaller in lesions prepared with a standard noncompliant balloon due to negative remodeling.

CONCLUSIONS

Lesion preparation with a scoring balloon before implantation of a Magmaris BRS resulted in a significantly larger minimal lumen area after 6 months due to less negative remodeling compared with lesion preparation with a standard noncompliant balloon.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04666584.

Outcomes of Optical Coherence Tomography-Guided and Angiography-Guided Primary Percutaneous Coronary Intervention in Patients with ST-Segment Elevation Myocardial Infarction

Background

Despite the administration of timely reperfusion treatment, patients with acute myocardial infarction have a high mortality rate and poor prognosis. The potential impact of intraluminal imaging guidance, such as optical coherence tomography (OCT), on improving patient outcomes has yet to be conclusively studied. Therefore, we conducted a retrospective cohort study to compare OCT-guided primary percutaneous coronary intervention (PCI) versus angiography-guided for patients with ST-segment elevation myocardial infarction (STEMI).

Methods

This study enrolled 1396 patients with STEMI who underwent PCI, including 553 patients who underwent OCT-guided PCI and 843 patients who underwent angiography-guided PCI. The clinical outcome was a composite of cardiovascular death, myocardial infarction, admission due to heart failure, stroke, and unplanned revascularization at the 4-year follow-up.

Results

The prevalence of major adverse cardiovascular events in OCT-guided group was not significantly lower compared to those without OCT guidance after adjustment (unadjusted hazard ratio (HR), 1.582; 95% confidence interval (CI), 1.300-1.924; p < 0.001; adjusted HR, 1.095; adjusted 95% CI, 0.883-1.358; p = 0.409). The prevalence of cardiovascular death was significantly lower in patients with OCT guidance compared to those without before and after adjustment (unadjusted HR, 3.303; 95% CI, 2.142-5.093; p < 0.001; adjusted HR, 2.025; adjusted 95% CI, 1.225-3.136; p = 0.004).

Conclusions

OCT-guided primary PCI used to treat STEMI was associated with reduced long-term cardiovascular death.

National Trends, Mortality and Outcomes in Intravascular Imaging-Guided Versus Angiography-Guided Percutaneous Coronary Intervention in the United States

Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have become increasingly utilized in patients undergoing percutaneous coronary intervention (PCI). Despite these purported advantages, prior reports regarding the use of IVUS and OCT have indicated that contemporary use of intravascular imaging remains low with significant regional variation. Here, we present the findings of an updated contemporary analysis regarding the use of IVUS/OCT-guided PCI versus angiography-guided PCI in the United States. We also evaluated in-hospital mortality and clinical outcomes between IVUS/OCT-guided PCI versus angiography-guided PCI-only over million patients in the United States. There has been a significant decrease in the number of PCIs performed, while there has been increasing in the trend of IVUS/OCT-guided PCI over this period. Most importantly, we found that IVUS/OCT-guided PCI was associated with better clinical outcomes in terms of in-hospital mortality, compared with angiography-guided PCI.

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

BACKGROUND AND AIMS

Observational registries have suggested that optical coherence tomography (OCT) imaging-derived parameters may predict adverse events after drug-eluting stent (DES) implantation. The present analysis sought to determine the OCT predictors of clinical outcomes from the large-scale ILUMIEN IV trial.

METHODS

ILUMIEN IV was a prospective, single-blind trial of 2487 patients with diabetes or high-risk lesions randomized to OCT-guided versus angiography-guided DES implantation. All patients underwent final OCT imaging (blinded in the angiography-guided arm). From more than 20 candidates, the independent OCT predictors of 2-year target lesion failure (TLF; the primary endpoint), cardiac death or target-vessel myocardial infarction (TV-MI), ischaemia-driven target lesion revascularization (ID-TLR), and stent thrombosis were analysed by multivariable Cox proportional hazard regression in single treated lesions.

RESULTS

A total of 2128 patients had a single treated lesion with core laboratory-analysed final OCT. The 2-year Kaplan-Meier rates of TLF, cardiac death or TV-MI, ID-TLR, and stent thrombosis were 6.3% (n = 130), 3.3% (n = 68), 4.3% (n = 87), and 0.9% (n = 18), respectively. The independent predictors of 2-year TLF were a smaller minimal stent area (per 1 mm2 increase: hazard ratio 0.76, 95% confidence interval 0.68-0.89, P < .0001) and proximal edge dissection (hazard ratio 1.77, 95% confidence interval 1.20-2.62, P = .004). The independent predictors of cardiac death or TV-MI were smaller minimal stent area and longer stent length; of ID-TLR were smaller intra-stent flow area and proximal edge dissection; and of stent thrombosis was smaller minimal stent expansion.

CONCLUSIONS

In the ILUMIEN IV trial, the most important OCT-derived post-DES predictors of both safety and effectiveness outcomes were parameters related to stent area, expansion and flow, proximal edge dissection, and stent length.

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

BACKGROUND

Despite improvement in devices, in-stent restenosis remains a frequent and challenging complication of percutaneous coronary interventions.

METHODS AND RESULTS

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

CONCLUSIONS

OCT identified neoatherosclerosis and neointimal hyperplasia in comparable proportions. Stent underexpansion was frequent and favored subsequent adverse clinical outcomes.

Contemporary Functional Coronary Angiography: An Update

Functional coronary angiography (FCA) is a novel modality for assessing the physiology of coronary lesions, going beyond anatomical visualization by traditional coronary angiography. FCA incorporates indices like fractional flow reserve (FFR) and instantaneous wave-free ratio (IFR), which utilize pressure measurements across coronary stenoses to evaluate hemodynamic impacts and to guide revascularization strategies. In this review, we present traditional and evolving modalities and uses of FCA. We will also evaluate the existing evidence and discuss the applicability of FCA in various clinical scenarios. Finally, we provide insight into emerging evidence, current challenges, and future directions in FCA.

Optical coherence tomography to guide percutaneous coronary intervention

Percutaneous coronary intervention (PCI) has been most commonly guided by coronary angiography. However, to overcome the inherent limitations of conventional coronary angiography, there has been an increasing interest in the adjunctive tools of intracoronary imaging for PCI guidance. Recently, optical coherence tomography (OCT) has garnered substantial attention as a valid intravascular imaging modality for guiding PCI. However, despite the unparalleled high-resolution imaging capability of OCT, which offers detailed anatomical information on coronary lesion morphology and PCI optimisation, its broad application in routine PCI practice remains limited. Several factors may have curtailed the widespread adoption of OCT-guided PCI in daily practice, including the transitional challenge from intravascular ultrasound (IVUS), the experienced skill required for image acquisition and interpretation, the lack of a uniform algorithm for OCT-guided PCI optimisation, and the limited clinical evidence. Herein, we provide an in-depth review of OCT-guided PCI, involving the technical aspects, optimal strategies for OCT-guided PCI, and the wide application of OCT-guided PCI in various anatomical subsets. Special attention is given to the latest clinical evidence from recent randomised clinical trials with respect to OCT-guided PCI.

Comparison of Long-Term Outcomes Between Intravascular Ultrasound-, Optical Coherence Tomography- and Angiography-Guided Stent Implantation: A Meta-Analysis

Intravascular ultrasonography (IVUS) and optical coherence tomography (OCT) guided percutaneous coronary interventions (PCI) are alternative techniques to angiography-guided (ANG-g) PCI in patients with coronary artery disease (CAD), especially for optimal stent deployment in coronary arteries. We conducted a network meta-analysis including studies comparing those three techniques. We searched databases for studies that compared IVUS, OCT, and ANG-g PCI in patients with CAD. Overall, 52 studies with 231,137 patients were included in this meta-analysis. ANG-g PCI had higher major adverse cardiovascular events (MACEs), all-cause death, cardiac death, myocardial infarction (MI), target lesion revascularization (TLR), and stent thrombosis (ST) than IVUS-guided PCI. Of note, both OCT-guided and IVUS-guided PCI had similar outcomes. The frequency of MACEs, cardiac death, and MI were higher in ANG-g PCI than in OCT-guided PCI. The highest benefit was established with OCT for MACEs (P-score=.973), MI (P-score=.823), and cardiac death (P-score=.921) and with IVUS for all-cause death (P-score=.792), TLR (P -score=.865), and ST (P-score=.930). This network meta-analysis indicated that using OCT or IVUS for optimal stent implantation provides better outcomes in comparison with ANG-g in patients with CAD undergoing PCI.

Contemporary Trends and Outcomes of Intravascular Lithotripsy in Percutaneous Coronary Intervention: Insights From BMC2

BACKGROUND

With an aging population and an increase in the comorbidity burden of patients undergoing percutaneous coronary intervention (PCI), the management of coronary calcification for optimal PCI is critical in contemporary practice.

OBJECTIVES

This study sought to examine the trends and outcomes of coronary intravascular lithotripsy (IVL), rotational/orbital atherectomy, or both among patients who underwent PCI in Michigan.

METHODS

We included all PCIs between January 1, 2021, and June 30, 2022, performed at 48 Michigan hospitals. Outcomes included in-hospital major adverse cardiac events (MACEs) and procedural success.

RESULTS

IVL was used in 1,090 patients (2.57%), atherectomy was used in 1,743 (4.10%) patients, and both were used in 240 patients (0.57% of all PCIs). IVL use increased from 0.04% of PCI cases in January 2021 to 4.28% of cases in June 2022, ultimately exceeding the rate of atherectomy use. The rate of MACEs (4.3% vs 5.4%; P = 0.23) and procedural success (89.4% vs 89.1%; P = 0.88) were similar among patients treated with IVL compared with atherectomy, respectively. Only 15.6% of patients treated with IVL in contemporary practice were similar to the population enrolled in the pivotal IVL trials. Among such patients (n = 169), the rate of MACEs (0.0%) and procedural success (94.7%) were similar to the outcomes reported in the pivotal IVL trials.

CONCLUSIONS

Since its introduction in February 2021, coronary IVL use has steadily increased, exceeding atherectomy use in Michigan by February 2022. Contemporary use of IVL and atherectomy is generally associated with high rates of procedural success and low rates of complications.

Machine Learning Constructed Based on Patient Plaque and Clinical Features for Predicting Stent Malapposition: A Retrospective Study

BACKGROUND

Stent malapposition (SM) following percutaneous coronary intervention (PCI) for myocardial infarction continues to present significant clinical challenges. In recent years, machine learning (ML) models have demonstrated potential in disease risk stratification and predictive modeling.

HYPOTHESIS

ML models based on optical coherence tomography (OCT) imaging, laboratory tests, and clinical characteristics can predict the occurrence of SM.

METHODS

We studied 337 patients from the Affiliated Hospital of Zunyi Medical University, China, who had PCI and coronary OCT from May to October 2023. We employed nested cross-validation to partition patients into training and test sets. We developed five ML models: XGBoost, LR, RF, SVM, and NB based on calcification features. Performance was assessed using ROC curves. Lasso regression selected features from 46 clinical and 21 OCT imaging features, which were optimized with the five ML algorithms.

RESULTS

In the prediction model based on calcification features, the XGBoost model and SVM model exhibited higher AUC values. Lasso regression identified five key features from clinical and imaging data. After incorporating selected features into the model for optimization, the AUC values of all algorithmic models showed significant improvements. The XGBoost model demonstrated the highest calibration accuracy. SHAP values revealed that the top five ranked features influencing the XGBoost model were calcification length, age, coronary dissection, lipid angle, and troponin.

CONCLUSION

ML models developed using plaque imaging features and clinical characteristics can predict the occurrence of SM. ML models based on clinical and imaging features exhibited better performance.

Innovations in Intracoronary Imaging: Present Clinical Practices and Future Outlooks

Engaging intracoronary imaging (IC) techniques such as intravascular ultrasound or optical coherence tomography enables the precise description of vessel architecture. These imaging modalities have well-established roles in providing guidance and optimizing percutaneous coronary intervention (PCI) outcomes. Furthermore, IC is increasingly recognized for its diagnostic capabilities, as it has the unique capacity to reveal vessel wall characteristics that may not be apparent through angiography alone. This manuscript thoroughly reviews the contemporary landscape of IC in clinical practice. Focused on current methodologies, the review explores the utility and advancements in IC techniques. Emphasizing their role in clarifying coronary pathophysiology, guiding PCI, and optimizing patient outcomes, the manuscript critically evaluates the strengths and limitations of each modality. Additionally, the integration of IC into routine clinical workflows and its impact on decision-making processes are discussed. By synthesizing the latest evidence, this review provides valuable insights for clinicians, researchers, and healthcare professionals involved in the dynamic field of interventional cardiology.

Elucidating the Relationship between Neutrophil-Lymphocyte Ratio and Plaque Composition in Patients with Drug-Eluting Stent Restenosis by Virtual Histology-Intravascular Ultrasound

(1) Background: In-stent Restenosis (ISR) is a major factor influencing the prognosis and revascularization of target lesions. The plaque composition is unclear; therefore, it is critical to investigate ISR composition to identify clinical intervention markers. (2) Methods: This study was conducted on 36 patients with drug-eluting stent restenosis. The patients were classified into a Low Neutrophil-Lymphocyte Ratio (L-NLR) and High Neutrophil-Lymphocyte Ratio (H-NLR) according to the median NLR level of 36 patients. Discrepancies in the current information such as baseline data, biochemical examination, cardiac ultrasound data, etc., were examined to identify the underlying risk factors, and a multifactorial linear regression analysis of plaque properties was conducted. (3) Results: NLR = 2.64 was utilized to classify 18 patients into the L-NLR group and 18 patients into the H-NLR group. There were statistically significant differences in age, a pre-percutaneous coronary intervention (PCI) SYNTAX II score, a C-reactive protein (CRP), interleukin (IL)-6, plaque loading, a fibro-lipid tissue area, calcified nubs, and virtual histology-thin fibrous cap atherosclerotic (VH-TCFA). The significant impacts of variations in age, neutrophil-lymphocyte ratio (NLR) levels, and IL-6 levels on the plaque stress and percentage of the fibro-lipid tissue in virtual histology-intravascular ultrasound (VH-IVUS) were identified through multifactorial linear regression. (4) Conclusions: The high NLR group demonstrated increased myocardial injury severity, consistent with higher SYNTAX II scores, a higher plaque burden, and higher proportions of vulnerable components. NLR proved to be a risk factor for both the plaque load and the proportion of the fibro-lipid tissue in ISR.

Quantitative Coronary Angiography vs Intravascular Ultrasonography to Guide Drug-Eluting Stent Implantation: A Randomized Clinical Trial

Importance

Although intravascular ultrasonography (IVUS) guidance promotes favorable outcomes after percutaneous coronary intervention (PCI), many catheterization laboratories worldwide lack access.

Objective

To investigate whether systematic implementation of quantitative coronary angiography (QCA) to assist angiography-guided PCI could be an alternative strategy to IVUS guidance during stent implantation.

Design, Setting, and Participants

This randomized, open-label, noninferiority clinical trial enrolled adults (aged ≥18 years) with chronic or acute coronary syndrome and angiographically confirmed native coronary artery stenosis requiring PCI. Patients were enrolled in 6 cardiac centers in Korea from February 23, 2017, to August 23, 2021, and follow-up occurred through August 25, 2022. All principal analyses were performed according to the intention-to-treat principle.

Interventions

After successful guidewire crossing of the first target lesion, patients were randomized in a 1:1 ratio to receive either QCA- or IVUS-guided PCI.

Main Outcomes and Measures

The primary outcome was target lesion failure at 12 months, defined as a composite of cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization. The trial was designed assuming an event rate of 8%, with the upper limit of the 1-sided 97.5% CI of the absolute difference in 12-month target lesion failure (QCA-guided PCI minus IVUS-guided PCI) to be less than 3.5 percentage points for noninferiority.

Results

The trial included 1528 patients who underwent PCI with QCA guidance (763; mean [SD] age, 64.1 [9.9] years; 574 males [75.2%]) or IVUS guidance (765; mean [SD] age, 64.6 [9.5] years; 622 males [81.3%]). The post-PCI mean (SD) minimum lumen diameter was similar between the QCA- and IVUS-guided PCI groups (2.57 [0.55] vs 2.60 [0.58] mm, P = .26). Target lesion failure at 12 months occurred in 29 of 763 patients (3.81%) in the QCA-guided PCI group and 29 of 765 patients (3.80%) in the IVUS-guided PCI group (absolute risk difference, 0.01 percentage points [95% CI, -1.91 to 1.93 percentage points]; hazard ratio, 1.00 [95% CI, 0.60-1.68]; P = .99). There was no difference in the rates of stent edge dissection (1.2% vs 0.7%, P = .25), coronary perforation (0.2% vs 0.4%, P = .41), or stent thrombosis (0.53% vs 0.66%, P = .74) between the QCA- and IVUS-guided PCI groups. The risk of the primary end point was consistent regardless of subgroup, with no significant interaction.

Conclusions and Relevance

Findings of this randomized clinical trial indicate that QCA and IVUS guidance during PCI showed similar rates of target lesion failure at 12 months. However, due to the lower-than-expected rates of target lesion failure in this trial, the findings should be interpreted with caution.

Trial Registration

ClinicalTrials.gov Identifier: NCT02978456.

Current Management of In-Stent Restenosis

In-stent restenosis (ISR) remains the primary cause of target lesion failure following percutaneous coronary intervention (PCI), resulting in 10-year incidences of target lesion revascularization at a rate of approximately 20%. The treatment of ISR is challenging due to its inherent propensity for recurrence and varying susceptibility to available strategies, influenced by a complex interplay between clinical and lesion-specific conditions. Given the multiple mechanisms contributing to the development of ISR, proper identification of the underlying substrate, especially by using intravascular imaging, becomes pivotal as it can indicate distinct therapeutic requirements. Among standalone treatments, drug-coated balloon (DCB) angioplasty and drug-eluting stent (DES) implantation have been the most effective. The main advantage of a DCB-based approach is the avoidance of an additional metallic layer, which may otherwise enhance neointimal hyperplasia, provide the substratum for developing neoatherosclerosis, and expose the patient to a persistently higher risk of coronary ischemic events. On the other hand, target vessel scaffolding by DES implantation confers relevant mechanical advantages over DCB angioplasty, generally resulting in larger luminal gain, while drug elution from the stent surface ensures the inhibition of neointimal hyperplasia. Nevertheless, repeat stenting with DES also implies an additional permanent metallic layer that may reiterate and promote the mechanisms leading to ISR. Against this background, the selection of either DCB or DES on a patient- and lesion-specific basis as well as the implementation of adjuvant treatments, including cutting/scoring balloons, intravascular lithotripsy, and rotational atherectomy, hold the potential to improve the effectiveness of ISR treatment over time. In this review, we comprehensively assessed the available evidence from randomized trials to define contemporary interventional treatment of ISR and provide insights for future directions.

Coronary Angiography, Intravascular Ultrasound, and Optical Coherence Tomography for Guiding of Percutaneous Coronary Intervention: A Systematic Review and Network Meta-Analysis

BACKGROUND

Results from multiple randomized clinical trials comparing outcomes after intravascular ultrasound (IVUS)- and optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) with invasive coronary angiography (ICA)-guided PCI as well as a pivotal trial comparing the 2 intravascular imaging (IVI) techniques have provided mixed results.

METHODS

Major electronic databases were searched to identify eligible trials evaluating at least 2 PCI guidance strategies among ICA, IVUS, and OCT. The 2 coprimary outcomes were target lesion revascularization and myocardial infarction. The secondary outcomes included ischemia-driven target lesion revascularization, target vessel myocardial infarction, death, cardiac death, target vessel revascularization, stent thrombosis, and major adverse cardiac events. Frequentist random-effects network meta-analyses were conducted. The results were replicated by Bayesian random-effects models. Pairwise meta-analyses of the direct components, multiple sensitivity analyses, and pairwise meta-analyses IVI versus ICA were supplemented.

RESULTS

The results from 24 randomized trials (15 489 patients: IVUS versus ICA, 46.4%, 7189 patients; OCT versus ICA, 32.1%, 4976 patients; OCT versus IVUS, 21.4%, 3324 patients) were included in the network meta-analyses. IVUS was associated with reduced target lesion revascularization compared with ICA (odds ratio [OR], 0.69 [95% CI, 0.54-0.87]), whereas no significant differences were observed between OCT and ICA (OR, 0.83 [95% CI, 0.63-1.09]) and OCT and IVUS (OR, 1.21 [95% CI, 0.88-1.66]). Myocardial infarction did not significantly differ between guidance strategies (IVUS versus ICA: OR, 0.91 [95% CI, 0.70-1.19]; OCT versus ICA: OR, 0.87 [95% CI, 0.68-1.11]; OCT versus IVUS: OR, 0.96 [95% CI, 0.69-1.33]). These results were consistent with the secondary outcomes of ischemia-driven target lesion revascularization, target vessel myocardial infarction, and target vessel revascularization, and sensitivity analyses generally did not reveal inconsistency. OCT was associated with a significant reduction of stent thrombosis compared with ICA (OR, 0.49 [95% CI, 0.26-0.92]) but only in the frequentist analysis. Similarly, the results in terms of survival between IVUS or OCT and ICA were uncertain across analyses. A total of 25 randomized trials (17 128 patients) were included in the pairwise meta-analyses IVI versus ICA where IVI guidance was associated with reduced target lesion revascularization, cardiac death, and stent thrombosis.

CONCLUSIONS

IVI-guided PCI was associated with a reduction in ischemia-driven target lesion revascularization compared with ICA-guided PCI, with the difference most evident for IVUS. In contrast, no significant differences in myocardial infarction were observed between guidance strategies.

Optimal lesion preparation before implantation of a Magmaris bioresorbable scaffold in patients with coronary artery stenosis: Rationale, design and methodology of the OPTIMIS study

Introduction

Percutaneous coronary intervention with implantation of a bioresorbable scaffold (BRS) provide the vessel support for a limited period allowing the vessel to restore normal vasomotion after degradation of the BRS, opposed to treatment with drug-eluting stents where the metal persist in the vessel wall. Late lumen loss and reduction in lumen area after implantation have been reported. The purpose of this study was to investigate whether intense pre-dilatation before BRS implantation resulted in less reduction of minimal lumen area at 6- and 12-month follow-up after implantation of a Magmaris BRS (MgBRS). Coronary imaging with optical coherence tomography (OCT) and intravascular ultrasound (IVUS) was assessed to track changes in lumen and vessel dimensions.

Methods

The prospective Optimal lesion PreparaTion before Implantation of the Magmaris bioresorbable scaffold In patients with coronary artery Stenosis (OPTIMIS) study randomly assigned eighty-two patients with chronic coronary syndrome to two pre-dilatation treatment strategies. Patients were randomized in a 1:1 ratio to pre-dilatation with either a non-compliant scoring balloon or a standard non-compliant balloon prior to implantation of a MgBRS. The treated segment was evaluated with OCT and IVUS at baseline, after 6 and 12 months to assess changes in lumen and vessel dimensions. The hypothesis was that more intense pre-dilatation with a non-compliant scoring balloon before MgBRS implantation can reduce the risk of late lumen reduction compared to standard pre-dilatation. The power calculation used expected MLA after 6 months (6.22 mm2 for the scoring balloon and 5.01 mm2 for the standard non-compliant balloon), power of 80 %, significance level of 0.05 and expected drop-out rate of 15 %, requiring 82 patients to be enrolled.

Results

Eighty-two patients were included in the study. Enrollment was from December 2020 to September 2023.

Conclusion

The hypothesis was that more intense pre-dilatation with a non-compliant scoring balloon before MgBRS implantation can reduce the risk of late lumen reduction compared to standard pre-dilatation.

Management of Calcified Coronary Lesions

With an aging population, coronary calcification is increasingly encountered in modern day interventional practice. Unfortunately, it is associated with lower procedural success and higher rates of periprocedural complications, such as failure to deliver stents, perforations, dissections, and other major adverse cardiac events. Furthermore, suboptimal stent deployment in the setting of severe calcification is associated with both short-and long-term major adverse cardiac events, including stent thrombosis, MI, in-stent restenosis, and target lesion revascularization. A variety of treatment options for these lesions exist, including specialized balloons, atherectomy, and intravascular lithotripsy. While there is currently no universally accepted algorithm for choosing between these treatment strategies, several different algorithms exist, and the optimization of these treatment regimens will continue to evolve in the coming years. This review aims to provide insights on the different therapeutic modalities and an understanding of the current body of evidence.

Roadmap on the use of artificial intelligence for imaging of vulnerable atherosclerotic plaque in coronary arteries

Artificial intelligence (AI) is likely to revolutionize the way medical images are analysed and has the potential to improve the identification and analysis of vulnerable or high-risk atherosclerotic plaques in coronary arteries, leading to advances in the treatment of coronary artery disease. However, coronary plaque analysis is challenging owing to cardiac and respiratory motion, as well as the small size of cardiovascular structures. Moreover, the analysis of coronary imaging data is time-consuming, can be performed only by clinicians with dedicated cardiovascular imaging training, and is subject to considerable interreader and intrareader variability. AI has the potential to improve the assessment of images of vulnerable plaque in coronary arteries, but requires robust development, testing and validation. Combining human expertise with AI might facilitate the reliable and valid interpretation of images obtained using CT, MRI, PET, intravascular ultrasonography and optical coherence tomography. In this Roadmap, we review existing evidence on the application of AI to the imaging of vulnerable plaque in coronary arteries and provide consensus recommendations developed by an interdisciplinary group of experts on AI and non-invasive and invasive coronary imaging. We also outline future requirements of AI technology to address bias, uncertainty, explainability and generalizability, which are all essential for the acceptance of AI and its clinical utility in handling the anticipated growing volume of coronary imaging procedures.

Evaluation of the thickness of coronary calcium by 60-MHz intravascular ultrasound: head-to-head comparison with optical frequency domain imaging

The region behind the coronary calcium could not be visualized by intravascular ultrasound (IVUS) because of acoustic shadow. However, some pathological studies have shown that IVUS delineated the vessel border behind thin coronary calcium sheets. This study aimed to reveal whether recent IVUS can visualize the region behind thin coronary calcium sheets. Using 534 cross-sectional optical frequency domain images (OFDI), including severe calcified coronary lesions, calcium sheet thickness was measured by every 1°. Accordingly, the visibility of the vessel border behind the coronary calcium sheet was evaluated using 60-MHz IVUS images, which were longitudinally linked with OFDI ones. After carefully coordinating with the axial position, the association between the IVUS-derived permeability of the coronary calcium sheet and calcium thickness was evaluated. The maximum and mean calcium thickness by OFDI was 0.88 ± 0.39 and 0.62 ± 0.30 mm, respectively. By 60-MHz IVUS, 12.1% of the coronary calcium sheets had permeable segments. Comparing between OFDI and IVUS images, 48.6% of the coronary calcium sheets with maximum thickness ≤ 0.3 mm were sometimes permeable by 60-MHz IVUS, whereas most > 0.5 mm thick calcium sheets were impermeable. In the receiver operating characteristic curve analysis, the best cutoff values for the maximum and mean thickness of permeable calcium were 0.48 and 0.31 mm, respectively. Thus, 60-MHz IVUS can occasionally visualize the region behind a thin coronary calcium sheet. When using 60-MHz IVUS, this finding may be a predictive marker of calcium sheet with a thickness of < 0.5 mm.

Rotational Atherectomy, Orbital Atherectomy, and Intravascular Lithotripsy Comparison for Calcified Coronary Lesions

In order to improve the percutaneous treatment of coronary artery calcifications (CAC) before stent implantation, methods such as rotational atherectomy (RA), orbital atherectomy (OA), and coronary intravascular lithotripsy (IVL) were invented. These techniques use different mechanisms of action and therefore have various short- and long-term outcomes. IVL employs sonic waves to modify CAC, whereas RA and OA use a rapidly rotating burr or crown. These methods have specific advantages and limitations, regarding their cost-efficiency, the movement of the device, their usefulness given the individual anatomy of both the lesion and the vessel, and the risk of specified complications. This study reviews the key findings of peer-reviewed articles available on Google Scholar with the keywords RA, OA, and IVL. Based on the collected data, successful stent delivery was assessed as 97.7% for OA, 92.4% for IVL, and 92.5% for RA, and 30-day prevalence of MACE (Major Adverse Cardiac Events) in OA-10.4%, IVL-7.2%, and RA-5%. There were no significant differences in the 1-year MACE. Compared to RA, OA and IVL are cost-effective approaches, but this is substantially dependent on the reimbursement system of the particular country. There is no standard method of CAC modification; therefore, a tailor-made approach is required.

Outcomes With Intravascular Ultrasound and Optical Coherence Tomography Guidance in Percutaneous Coronary Intervention

Intracoronary imaging has become an important tool in the treatment of complex lesions with percutaneous coronary intervention (PCI). This retrospective cohort study identified 1,118,475 patients with PCI from the Nationwide Readmissions Database from 2017 to 2019. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) were identified with appropriate International Classification of Diseases, Tenth Revision codes. The primary outcome was major adverse cardiac events. The secondary outcomes include net adverse clinical events (NACEs), all-cause mortality, myocardial infarction (MI) readmission, admission for stroke, and emergency revascularization. The multivariate Cox proportional hazard regression was used to adjust for demographic and co-morbid confounders. Of 1,118,475 PCIs, 86,140 (7.7%) used IVUS guidance and 5,617 (0.5%) used OCT guidance. The median follow-up time was 184 days. The primary outcome of major adverse cardiac events was significantly lower for the IVUS (6.5% vs 7.6%; hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.86 to 0.91, p <0.001) and OCT (4.4% vs 7.6%; HR 0.69, 95% CI 0.61 to 0.79, p <0.001) groups. IVUS was associated with significantly lower rates of NACEs (8.4% vs 9.4%; HR 0.92, 95% CI 0.89 to 0.94, p <0.001), all-cause mortality (3.5% vs 4.3%; HR 0.85, 95% CI 0.82 to 0.88, p <0.001), readmission for MI (2.7% vs 3.0%; HR 0.95, 95% CI 0.91 to 0.99, p = 0.012), and admission for stroke (0.5% vs 0.6%; HR 0.86, 95% CI 0.78 to 0.95, p = 0.002). OCT was associated with significantly lower rates of NACEs (6.6% vs 9.4%; HR 0.81, 95% CI 0.73 to 0.89, p <0.001) and all-cause mortality (1.8% vs 4.3%; HR 0.51, 95% CI 0.42 to 0.63, p <0.001). Emergency revascularization was not significantly different with IVUS guidance. Readmission for MI, stroke, and emergency revascularization were not significantly different with OCT guidance. A subgroup analysis of patients with ST-elevation MI and non-ST-elevation MI showed similar results. In conclusion, the use of IVUS and OCT guidance with PCI were associated with significantly lower rates of morbidity and mortality in real-world practice.

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.

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.

Comparison of intravascular ultrasound, optical coherence tomography, and conventional angiography-guided percutaneous coronary interventions: A systematic review, network meta-analysis, and meta-regression

BACKGROUND

Intracoronary imaging modalities, including intravascular ultrasound (IVUS) and optical coherence tomography (OCT), provide valuable supplemental data unavailable on coronary angiography (CA) and have shown to improve clinical outcomes. We sought to compare the clinical efficacy of IVUS, OCT, and conventional CA-guided percutaneous coronary interventions (PCI).

METHODS

Frequentist and Bayesian network meta-analyses of randomized clinical trials were performed to compare clinical outcomes of PCI performed with IVUS, OCT, or CA alone.

RESULTS

A total of 28 trials comprising 12,895 patients were included. IVUS when compared with CA alone was associated with a significantly reduced risk of major adverse cardiovascular events (MACE) (risk ratio: [RR] 0.74, 95% confidence interval: [CI] 0.63-0.88), cardiac death (RR: 0.64, 95% CI: 0.43-0.94), target lesion revascularization (RR: 0.68, 95% CI: 0.57-0.80), and target vessel revascularization (RR: 0.64, 95% CI: 0.50-0.81). No differences in comparative clinical efficacy were found between IVUS and OCT. Rank probability analysis bestowed the highest probability to IVUS in ranking as the best imaging modality for all studied outcomes except for all-cause mortality.

CONCLUSION

Compared with CA, the use of IVUS in PCI guidance provides significant benefit in reducing MACE, cardiac death, and revascularization. OCT had similar outcomes to IVUS, but more dedicated studies are needed to confirm the superiority of OCT over CA.

Comparison of definitions of coronary artery reference sizes and effects on stent selection and evaluation of stent expansion

Accurate determination of coronary reference size is essential for optimal stent selection and evaluation of stent expansion during percutaneous coronary intervention (PCI). Several approaches for reference size estimation have been published with no universal agreement. The aim of this study was to investigate if potential differences in coronary reference size estimation lead to differences in stent and balloon selection and in detection of stent under expansion. Definitions for coronary reference size estimation, stent size selection, and stent expansion were identified in 17 randomized controlled trials. The identified methods were applied in a population of 32 clinical cases. Reference size estimates ranged up to 1.35mm, and indicated nominal stent size ranged up to 1.0 mm in the same case depending on method. Mean relative stent expansion ranged from 54±12% to mean 100±29% depending on the applied reference method. Choice of method for reference size estimation using intravascular imaging may influence stent selection and greatly affects evaluation of post-PCI stent expansion.

Accuracy of IVUS-Based Machine Learning Segmentation Assessment of Coronary Artery Dimensions and Balloon Sizing

Background

Accurate intravascular ultrasound (IVUS) measurements are important in IVUS-guided percutaneous coronary intervention optimization by choosing the appropriate device size and confirming stent expansion.

Objectives

The purpose of this study was to assess the accuracy of machine learning (ML) automatic segmentation of coronary artery vessel and lumen dimensions and balloon sizing.

Methods

Using expert analysis as the gold standard, ML segmentation of 60 MHz IVUS images was developed using 8,076 IVUS cross-sectional images from 234 patients, which were randomly split into training (83%) and validation (17%) data sets. The performance of ML segmentation was then evaluated using an independent test data set (437 images from 92 patients). The endpoints were the agreement rate between ML vs experts' measurements for appropriate balloon size selection, and lumen and acute stent areas. Appropriate balloon size was determined by rounding down from the mean vessel diameter or rounding up from the mean lumen diameter to the next balloon size. The difference of lumen area ≥0.5 mm2 was considered as clinically significant.

Results

ML model segmentation correlated well with experts' segmentation for training data set with a correlation coefficient of 0.992 and 0.993 for lumen and vessel areas, respectively. The agreement rate in lumen and acute stent areas was 85.5% and 97.0%, respectively. The agreement rate for appropriate balloon size selection was 70.6% by vessel diameter only and 92.4% by adding lumen diameter.

Conclusions

ML model IVUS segmentation measurements were well-correlated with those of experts and selected an appropriate balloon size in more than 90% of images.

Outcomes of Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Non-ST-Elevation Myocardial Infarction-Propensity Matched Regression Analysis

Intravascular ultrasound (IVUS) guided percutaneous coronary intervention (PCI) is indicated in complex interventions. There is a paucity of evidence for outcomes with large studies on using IVUS during PCI in non-ST-elevation myocardial infarction (NSTEMI). Our objective was to compare the in-hospital outcome of IVUS-guided with that of nonguided PCI among NSTEMI hospitalizations. The National Inpatient Sample (2016 to 2019) was queried to identify all hospitalizations with a principal diagnosis of NSTEMI. In our study, we compared outcomes of PCI with and without IVUS guidance using a multivariate logistic regression model after propensity score matching, with the primary outcome being in-hospital mortality. A total of 671,280 NSTEMI-related hospitalizations were identified, of whom 48,285 (7.2%) underwent IVUS-guided PCI compared with 622,995 (92.8%) who underwent non-IVUS PCI. After adjusted analysis on matched pairs, we found that IVUS-guided PCI had a lower risk of in-hospital mortality than that of non-IVUS PCI (adjusted odds ratio [aOR] 0.736, confidence interval (CI) 0.578 to 0.937, p = 0.013). However, there was a higher use of mechanical circulatory support in the IVUS-guided PCI (aOR 2.138, CI 1.84 to 2.47, p <0.001) than in non-IVUS PCI. The odds of cardiogenic shock (aOR 1.11, CI 0.93 to 1.32, p = 0.233) and procedural complications (aOR 0.794, CI 0.549 to 1.14, p = 0.22) were similar between the cohorts. Hence, we conclude that patients with NSTEMIs who underwent IVUS-guided PCI had less risk of in-hospital mortality and a greater requirement of mechanical circulatory support than did those who underwent non-IVUS PCI, with no difference in procedural complications. Large prospective trials are essential to validate these findings.

Left Main Percutaneous Coronary Revascularization

Left main (LM) coronary artery disease accounts for approximately 4-6% of all percutaneous coronary interventions (PCIs). There has been mounting evidence indicating the non-inferiority of LM PCI as a revascularization option, particularly for those with a low SYNTAX score. The EXCEL and NOBEL trials have shaped current guidelines. The European Society of Cardiology assigned a class 2a (level of evidence B) for isolated LM disease involving the shaft and ostium and a class IIb (level of evidence B) for isolated LM disease involving the bifurcation or additional two- or three-vessel disease and a SYNTAX score <32. However, data on the use of a single stent or an upfront two-stent strategy for distal LM disease are conflicting, wherein the EBC Main trial reported similar outcomes with a stepwise provisional approach and the DKCRUSH-V trial reported better outcomes with an upfront two-stent strategy using the 'double-kissing' crush technique. Although several studies have noted better immediate results with image-guided PCI, there are few data on outcomes in LM disease specifically. In fact, the uptake of imaging in the aforementioned landmark trials was only 40%. More importantly, the role of mechanical circulatory support (MCS) has been less well studied in LM PCI. Indiscriminate use of MCS for LM PCI has been noted in clinical practice. Trials evaluating the benefit of MCS in high-risk PCI demonstrated no benefit. This review highlights contemporary trials as they apply to current practice in LM PCI.

SCAI Expert Consensus Statement on Management of In-Stent Restenosis and Stent Thrombosis

Stent failure remains the major drawback to the use of coronary stents as a revascularization strategy. Recent advances in imaging have substantially improved our understanding of the mechanisms underlying these occurrences, which have in common numerous clinical risk factors and mechanical elements at the time of stent implantation. In-stent restenosis remains a common clinical problem despite numerous improvements in-stent design and polymer coatings over the past 2 decades. It generates significant health care cost and is associated with an increased risk of death and rehospitalization. Stent thrombosis causes abrupt closure of the stented artery and therefore carries a high risk of myocardial infarction and death. This Society for Cardiovascular Angiography & Interventions (SCAI) Expert Consensus Statement suggests updated practical algorithmic approaches to in-stent restenosis and stent thrombosis. A pragmatic outline of assessment and management of patients presenting with stent failure is presented. A new SCAI classification that is time-sensitive with mechanistic implications of in-stent restenosis is proposed. Emphasis is placed on frequent use of intracoronary imaging and assessment of timing to determine the precise etiology because that information is crucial to guide selection of the best treatment option. SCAI recommends image-guided coronary stenting at the time of initial implantation to minimize the occurrence of stent failure. When in-stent restenosis and stent thrombosis are encountered, imaging should be strongly considered to optimize the subsequent approach.

Drug-Coated Balloon in Primary Percutaneous Coronary Intervention

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