Prevalence and anatomical factors associated with stent under-expansion in non-severely calcified lesions.

BACKGROUND: Stent underexpansion, typically related to lesion calcification, is the strongest predictor of adverse events after percutaneous coronary intervention (PCI). Although uncommon, underexpansion may also occur in non-severely calcified lesions. AIM: We sought to identify the prevalence and anatomical characteristics of underexpansion in non-severely calcified lesions. METHODS: We included 993 patients who underwent optical coherence tomography-guided PCI of 1051 de novo lesions with maximum calcium arc <180°. Negative remodeling (NR) was the smallest lesion site external elastic lamina diameter that was also smaller than the distal reference. Stent expansion was evaluated using a linear regression model accounting for vessel tapering; underexpansion required both stent expansion <70% and stent area <4.5mm2. RESULTS: Underexpansion was observed in 3.6% of non-heavily calcified lesions (38/1051). Pre-stent maximum calcium arc and thickness were greater in lesions with versus without underexpansion (median 119° vs. 85°, p = 0.002; median 0.95 mm vs. 0.78 mm, p = 0.008). NR was also more common in lesions with underexpansion (44.7% vs. 24.5%, p = 0.007). In the multivariable logistic regression model, larger and thicker eccentric calcium, mid left anterior descending artery (LAD) location, and NR were associated with underexpansion in non-severely calcified lesions. The rate of underexpansion was especially high (30.7%) in lesions exhibiting all three morphologies. Two-year TLF tended to be higher in underexpanded versus non-underexpanded stents (9.7% vs. 3.7%, unadjusted hazard ratio [95% confidence interval] = 3.02 [0.92, 9.58], p = 0.06). CONCLUSION: Although underexpansion in the absence of severe calcium (<180°) is uncommon, mid-LAD lesions with NR and large and thick eccentric calcium were associated with underexpansion.

Optical Coherence Tomography-Based Functional Stenosis Assessment: FUSION-A Prospective Multicenter Trial.

BACKGROUND: Intravascular imaging and intracoronary physiology may both be used to guide and optimize percutaneous coronary intervention; however, they are rarely used together. The virtual flow reserve (VFR) is an optical coherence tomography (OCT)-based model of fractional flow reserve (FFR) facilitating the assessment of the physiological significance of coronary lesions. We aimed to validate the VFR assessment of intermediate coronary artery stenoses. METHODS: FUSION (Validation of OCT-Based Functional Diagnosis of Coronary Stenosis) was a multicenter, prospective, observational study comparing OCT-derived VFR to invasive FFR. VFR was mathematically derived from a lumped parameter flow model based on 3-dimensional lumen morphology. Patients undergoing coronary angiography with intermediate angiographic stenosis (40%-90%) requiring physiological assessment were enrolled. Investigational sites were blinded to the VFR analysis, and all OCT and FFR data were reviewed by an independent core laboratory. The coprimary end points were the sensitivity and specificity of VFR against FFR as the reference standard, each of which was tested against prespecified performance goals. RESULTS: After core laboratory review, 266 vessels in 224 patients from 25 US centers were included in the analysis. The mean angiographic diameter stenosis was 65.5%±14.9%, and the mean FFR was 0.83±0.11. Overall accuracy, sensitivity, and specificity of VFR versus FFR using a binary cutoff point of 0.80 were 82.0%, 80.4%, and 82.9%, respectively. The 97.5% lower confidence bound met the prespecified performance goal for sensitivity (71.6% versus 70%; P=0.01) and specificity (76.6% versus 75%; P=0.01). The area under the curve was 0.88 (95% CI, 0.84-0.92; P<0.0001). CONCLUSIONS: OCT-derived VFR demonstrates high sensitivity and specificity for predicting invasive FFR. Integrating high-resolution intravascular imaging with imaging-derived physiology may provide synergistic benefits as an adjunct to percutaneous coronary intervention. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT04356027.

Rotational atherectomy combined with cutting balloon to optimise stent expansion in calcified lesions: the ROTA-CUT randomised trial.

BACKGROUND: Percutaneous coronary intervention (PCI) of calcified lesions remains challenging for interventionalists. AIMS: We aimed to investigate whether combining rotational atherectomy (RA) with cutting balloon angioplasty (RA+CBA) results in more optimal stent expansion compared with RA followed by non-compliant balloon angioplasty (RA+NCBA). METHODS: ROTA-CUT is a prospective, multicentre, randomised trial of 60 patients with coronary artery disease undergoing PCI of moderately or severely calcified lesions with drug-eluting stent implantation. Patients were randomised 1:1 to either RA+CBA or RA+NCBA. The primary endpoint was the minimum stent area on intravascular ultrasound (IVUS). Secondary endpoints included minimum lumen area and stent expansion assessed by IVUS and acute lumen gain, final residual diameter stenosis and minimum lumen diameter assessed by angiography. Clinical endpoints were obtained at 30 days. RESULTS: The mean age was 71.1±9.4 years, and 22% were women. The procedural details of RA were similar between groups, as were procedure duration and contrast use. Minimum stent area was similar with RA+CBA versus RA+NCBA (6.7±1.7 mm2 vs 6.9±1.8 mm2; p=0.685). Furthermore, there were no significant differences regarding the other IVUS and angiographic endpoints. Procedural complications were rare, and 30-day clinical events included 2 myocardial infarctions and 1 target vessel revascularisation in the RA+CBA group and 1 myocardial infarction in the RA+NCBA group. CONCLUSIONS: Combining RA with CBA resulted in a similar minimum stent area compared with RA followed by NCBA in patients undergoing PCI of moderately or severely calcified lesions. RA followed by CBA was safe with rare procedural complications and few clinical adverse events at 30 days.

Changes in post-PCI physiology based on anatomical vessel location: a DEFINE PCI substudy.

BACKGROUND: Anatomical vessel location affects post-percutaneous coronary intervention (PCI) physiology. AIMS: We aimed to compare the post-PCI instantaneous wave-free ratio (iFR) in left anterior descending (LAD) versus non-LAD vessels and to identify the factors associated with a suboptimal post-PCI iFR. METHODS: DEFINE PCI was a multicentre, prospective, observational study in which a blinded post-PCI iFR pullback was used to assess residual ischaemia following angiographically successful PCI. RESULTS: Pre- and post-PCI iFR recordings of 311 LAD and 195 non-LAD vessels were compared. Though pre-PCI iFR in the LAD vessels (median 0.82 [0.63, 0.86]) were higher compared with those in non-LAD vessels (median 0.72 [0.49, 0.84]; p<0.0001), post-PCI iFR were lower in the LAD vessels (median 0.92 [0.88, 0.94] vs 0.98 [0.95, 1.00]; p<0.0001). The prevalence of a suboptimal post-PCI iFR of <0.95 was higher in the LAD vessels (77.8% vs 22.6%; p<0.0001). While the overall frequency of residual physiological diffuse disease (31.4% vs 38.6%; p=0.26) and residual focal disease in the non-stented segment (49.6% vs 50.0%; p=0.99) were similar in both groups, residual focal disease within the stented segment was more common in LAD versus non-LAD vessels (53.7% vs 27.3%; p=0.0009). Improvement in iFR from pre- to post-PCI was associated with angina relief regardless of vessel location. CONCLUSIONS: After angiographically successful PCI, post-PCI iFR is lower in the LAD compared with non-LAD vessels, resulting in a higher prevalence of suboptimal post-PCI iFR in LAD vessels. This difference is, in part, due to a greater frequency of a residual focal pressure gradient within the stented segment which may be amenable to more aggressive PCI.

Comprehensive Management of ANOCA, Part 1-Definition, Patient Population, and Diagnosis: JACC State-of-the-Art Review.

Angina with nonobstructive coronary arteries (ANOCA) is increasingly recognized and may affect nearly one-half of patients undergoing invasive coronary angiography for suspected ischemic heart disease. This working diagnosis encompasses coronary microvascular dysfunction, microvascular and epicardial spasm, myocardial bridging, and other occult coronary abnormalities. Patients with ANOCA often face a high burden of symptoms and may experience repeated presentations to multiple medical providers before receiving a diagnosis. Given the challenges of establishing a diagnosis, patients with ANOCA frequently experience invalidation and recidivism, possibly leading to anxiety and depression. Advances in scientific knowledge and diagnostic testing now allow for routine evaluation of ANOCA noninvasively and in the cardiac catheterization laboratory with coronary function testing (CFT). CFT includes diagnostic coronary angiography, assessment of coronary flow reserve and microcirculatory resistance, provocative testing for endothelial dysfunction and coronary vasospasm, and intravascular imaging for identification of myocardial bridging, with hemodynamic assessment as needed.

Comprehensive Management of ANOCA, Part 2-Program Development, Treatment, and Research Initiatives: JACC State-of-the-Art Review.

Centers specializing in coronary function testing are critical to ensure a systematic approach to the diagnosis and treatment of angina with nonobstructive coronary arteries (ANOCA). Management leveraging lifestyle, pharmacology, and device-based therapeutic options for ANOCA can improve angina burden and quality of life in affected patients. Multidisciplinary care teams that can tailor and titrate therapies based on individual patient needs are critical to the success of comprehensive programs. As coronary function testing for ANOCA is more widely adopted, collaborative research initiatives will be fundamental to improve ANOCA care. These efforts will require standardized symptom assessments and data collection, which will propel future large-scale clinical trials.

Accuracy and limitation of plaque detection by coronary CTA: a section-to-section comparison with optical coherence tomography.

Plaques identified by Coronary CT angiography (CCTA) are important in clinical diagnosis and primary prevention. High-risk plaque features by CCTA have been extensively validated using optical coherence tomography (OCT). However, since their general diagnostic performance and limitations have not been fully investigated, we sought to compare CCTA with OCT among consecutive vessel sections. We retrospectively compared 188 consecutive plaques and 84 normal sections in 41 vessels from 40 consecutive patients referred for chest pain evaluation who had both CCTA and OCT with a median time lapse of 1 day. The distance to reference points were used to co-register between the modalities and the diagnostic performance of CCTA was evaluated against OCT. Plaque categories evaluated by CT were calcified, non-calcified and mixed. The diagnostic performance of CCTA was excellent for detecting any plaque identified by OCT with the sensitivity, specificity, negative and positive predictive values and accuracy of 92%, 98%, 99%, 84% and 93%, respectively. The lower than expected negative predictive value was due to failure of detecting sub-millimeter calcified (≤ 0.25 mm2) (N = 12) and non-calcified plaques (N = 4). Misclassification of plaque type accounted for majority of false negative findings (25/41, 61%) which was most prevalent among the mixed plaque (19/41, 46%). There was calcification within mixed plaques (N = 5) seen by CCTA but missed by OCT. Our findings suggest that CCTA is excellent at identifying coronary plaques except those sub-millimeter in size which likely represent very early atherosclerosis, although the clinical implication of very mild atherosclerosis is yet to be determined.

Applied coronary physiology for planning and guidance of percutaneous coronary interventions. A clinical consensus statement from the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the European Society of Cardiology.

The clinical value of fractional flow reserve and non-hyperaemic pressure ratios are well established in determining an indication for percutaneous coronary intervention (PCI) in patients with coronary artery disease (CAD). In addition, over the last 5 years we have witnessed a shift towards the use of physiology to enhance procedural planning, assess post-PCI functional results, and guide PCI optimisation. In this regard, clinical studies have reported compelling data supporting the use of longitudinal vessel analysis, obtained with pressure guidewire pullbacks, to better understand how obstructive CAD contributes to myocardial ischaemia, to establish the likelihood of functionally successful PCI, to identify the presence and location of residual flow-limiting stenoses and to predict long-term outcomes. The introduction of new functional coronary angiography tools, which merge angiographic information with fluid dynamic equations to deliver information equivalent to intracoronary pressure measurements, are now available and potentially also applicable to these endeavours. Furthermore, the ability of longitudinal vessel analysis to predict the functional results of stenting has played an integral role in the evolving field of simulated PCI. Nevertheless, it is important to have an awareness of the value and challenges of physiology-guided PCI in specific clinical and anatomical contexts. The main aim of this European Association of Percutaneous Cardiovascular Interventions clinical consensus statement is to offer up-to-date evidence and expert opinion on the use of applied coronary physiology for procedural PCI planning, disease pattern recognition and post-PCI optimisation.

Impact of Eruptive vs Noneruptive Calcified Nodule Morphology on Acute and Long-Term Outcomes After Stenting.

BACKGROUND: Whether an eruptive or noneruptive target lesion calcified nodule (CN) portends worse acute and long-term clinical outcomes after stenting has not been established. OBJECTIVES: The authors sought to compare acute and long-term clinical outcomes in eruptive CN vs noneruptive CN morphology. METHODS: Using optical coherence tomography, an eruptive CN was defined as an accumulation of small calcium fragments protruding and disrupting the overlying fibrous cap, typically with small amount of thrombus. A noneruptive CN was defined as an accumulation of small calcium fragments with a smooth intact fibrous cap without an overlying thrombus. The primary endpoint was target lesion failure (TLF) including cardiac death, target vessel myocardial infarction, or clinically driven target lesion revascularization in patients with ≥6-month follow-up. RESULTS: Among 3,231 patients with evaluable pre- and postintervention OCT, 236 patients had lesions with CNs (7.3%). After eliminating 4 secondary lesions and 6 patients without ≥6-month follow-up, 126 (54.8%) lesions with eruptive CNs and 104 (45.2%) lesions with noneruptive CNs formed the current report. Compared with noneruptive CNs, eruptive CNs were independently associated with greater stent expansion (89.2% ± 18.7% vs. 81.5% ± 18.9%; P = 0.003) after adjusting for morphologic and procedural factors. At 2 years, eruptive CNs trended toward more TLF compared with noneruptive CNs (Kaplan-Meier estimates, 19.8% vs 12.5%; P = 0.11) and significantly more target lesion revascularization (18.3% vs 9.6%; P = 0.04). In the adjusted model, eruptive CNs were independently associated with 2-year TLF (HR: 2.07; 95% CI: 1.01-4.50; P = 0.048). CONCLUSIONS: Compared with noneruptive CN morphology, lesions with an eruptive CN appearance on optical coherence tomography had a worse poststent long-term clinical outcome despite better acute stent expansion.

Utility of optical coherence tomography in acute coronary syndromes.

Studies utilizing intravascular imaging have replicated the findings of histopathological studies, identifying the most common substrates for acute coronary syndromes (ACS) as plaque rupture, erosion, and calcified nodule, with spontaneous coronary artery dissection, coronary artery spasm, and coronary embolism constituting the less common etiologies. The purpose of this review is to summarize the data from clinical studies that have used high-resolution intravascular optical coherence tomography (OCT) to assess culprit plaque morphology in ACS. In addition, we discuss the utility of intravascular OCT for effective treatment of patients presenting with ACS, including the possibility of culprit lesion-based treatment by percutaneous coronary intervention.

Optical Coherence Tomography-Guided Percutaneous Coronary Intervention: Practical Application.

Optical coherence tomography (OCT) provides high-resolution imaging of coronary arteries and can be used to optimize percutaneous coronary intervention (PCI). Intracoronary OCT, however, has had limited adoption in clinical practice. Novelty and relative complexity of OCT interpretation compared with the more established intravascular ultrasound, lack of a standardized algorithm for PCI guidance, paucity of data from randomized trials, and lack of rebate for intravascular imaging have contributed to the modest practical adoption of OCT. We provide a practical step-by-step guide on how to use OCT in PCI, including device set-up, simplified image interpretation, and an algorithmic approach for PCI. optimization.

Visualizing Inside Conduits-Intraoperative Screening of Grafts by Optical Coherence Tomography.

PURPOSE: Saphenous vein graft (SVG) failure is a complex phenomenon, with technical, biologic, and local factors contributing to early and medium- and long-term failure after coronary artery bypass graft. Both technical and conduit factors may have significant impact on early SVG failure. DESCRIPTION: We review the complex factors that play a pathogenic role in SVG failure, followed by review of the existing literature on potential utility of high-definition optical coherence tomography (OCT) in comprehensive intraoperative assessment of SVGs. EVALUATION: We describe a new technique for intraoperative acquisition of OCT images in the harvested SVGs and introduce a classification system for pathologic processes that can be detected in the harvested SVG conduits by OCT. CONCLUSIONS: The potential impact on early graft failure of the exclusion of segments of SVGs that are less than optimal (ie, containing fibroatheroma, retained thrombus, sclerotic valves, or procurement injury) will be examined in the randomized controlled OCTOCAB (Intraoperative Optical Coherence Tomography of the Saphenous Vein Conduit in Patients Undergoing Coronary Artery Bypass Surgery) trial.

Impact of Intravascular Ultrasound-Derived Lesion-Specific Virtual Fractional Flow Reserve Predicts 3-Year Outcomes of Untreated Nonculprit Lesions: The PROSPECT Study.

BACKGROUND: Hemodynamic assessment of untreated nonculprit lesions was not studied in the PROSPECT study (Providing Regional Observations to Study Predictors of Events in the Coronary Tree). We developed a virtual intravascular ultrasound-derived lesion-specific fractional flow reserve (lesion-specific IVUS-FFR) algorithm to assess individual lesion-level FFR. We sought to investigate the relation between lesion-specific IVUS-FFR and major adverse cardiovascular events (MACE) arising from untreated nonculprit lesions in the PROSPECT study. METHODS: In PROSPECT, 697 patients with acute coronary syndromes underwent 3-vessel grayscale and virtual histology-IVUS to correlate untreated nonculprit plaque morphology with 3-year nonculprit related MACE (composite of cardiac death, cardiac arrest, myocardial infarction, or rehospitalization due to unstable or progressive angina). Lesion-specific IVUS-FFR was calculated from volumetric IVUS lumen area measurements at 0.4 mm intervals by applying a mathematical circulation model using basic fluid dynamics equations. RESULTS: Lesion-specific IVUS-FFR was analyzable in 3227 nonculprit lesions in 660 patients among whom 54 nonculprit MACE events (3 myocardial infarctions) occurred at median 3.4-year follow-up. By receiver-operating characteristic analysis, the best cutoff value of lesion-specific IVUS-FFR to predict nonculprit MACE was ≤0.95. After adjusting for patient and lesion characteristics, lesion-specific IVUS-FFR (hazard ratio, 4.83 [95% CI, 2.20-10.61]; P<0.001) was an independent predictor of 3-year nonculprit MACE, in addition to minimum lumen area≤4.0 mm2, plaque burden ≥70%, and virtual histology thin-cap fibroatheroma. CONCLUSIONS: Minor reductions in lesion-specific IVUS-FFR were independently associated with future nonculprit MACE arising from untreated angiographically mild stenoses along with previously established high-risk lesion morphological characteristics. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT00180466.