Development of machine learning models for fractional flow reserve prediction in angiographically intermediate coronary lesions.

BACKGROUND: Fractional flow reserve (FFR) represents the gold standard in guiding the decision to proceed or not with coronary revascularization of angiographically intermediate coronary lesion (AICL). Optical coherence tomography (OCT) allows to carefully characterize coronary plaque morphology and lumen dimensions. OBJECTIVES: We sought to develop machine learning (ML) models based on clinical, angiographic and OCT variables for predicting FFR. METHODS: Data from a multicenter, international, pooled analysis of individual patient's level data from published studies assessing FFR and OCT on the same target AICL were collected through a dedicated database to train (n = 351) and validate (n = 151) six two-class supervised ML models employing 25 clinical, angiographic and OCT variables. RESULTS: A total of 502 coronary lesions in 489 patients were included. The AUC of the six ML models ranged from 0.71 to 0.78, whereas the measured F1 score was from 0.70 to 0.75. The ML algorithms showed moderate sensitivity (range: 0.68-0.77) and specificity (range: 0.59-0.69) in detecting patients with a positive or negative FFR. In the sensitivity analysis, using 0.75 as FFR cut-off, we found a higher AUC (0.78-0.86) and a similar F1 score (range: 0.63-0.76). Specifically, the six ML models showed a higher specificity (0.71-0.84), with a similar sensitivity (0.58-0.80) with respect to 0.80 cut-off. CONCLUSIONS: ML algorithms derived from clinical, angiographic, and OCT parameters can identify patients with a positive or negative FFR.

Optical Coherence Tomography Measures Predicting Fractional Flow Reserve: The OMEF Study.

Background: Optical coherence tomography (OCT) allows to carefully characterize coronary plaque morphology and lumen dimensions. We sought to evaluate the value of OCT in predicting fractional flow reserve (FFR). Methods: We performed a multicenter, international, pooled analysis of individual patient-level data from published studies assessing FFR and OCT on the same vessel. Data from stable or unstable patients who underwent both FFR and OCT of the same coronary artery were collected through a dedicated database. Predefined OCT parameters were minimum lumen area (MLA), percentage area stenosis (%AS), and presence of thrombus or plaque rupture. Primary end point was FFR ≤0.80. Secondary outcome was the incidence of major adverse cardiac events in patients not undergoing revascularization based on negative FFR (>0.80). Results: A total of 502 coronary lesions in 489 patients were included. A significant correlation was observed between OCT-MLA and FFR values (R = 0.525; P < .001), and between OCT-%AS and FFR values (R = -0.482; P < .001). In Receiver operating characteristic analysis, MLA <2.0 mm2 showed a good discriminative power to predict an FFR ≤0.80 (AUC, 0.80), whereas %AS >73% showed a moderate discriminative power (AUC, 0.73). When considering proximal coronary segments, the best OCT cutoff values predicting an FFR ≤0.80 were MLA <3.1 mm2 (AUC, 0.82), and %AS >61% (AUC, 0.84). In patients with a negative FFR not revascularized, the combination of lower MLA and higher %AS had a trend toward worse outcome (which was statistically significant in the analysis restricted to proximal vessels). Conclusions: OCT lumen measures (MLA, %AS) may predict FFR, and different cutoffs are needed for proximal vessels.

Coronary Sinus Reducer Therapy for Refractory Angina and its Role in Modern Interventional Practice: A Contemporary Review.

Coronary sinus reducer (CSR) implantation is an emerging treatment option for patients with refractory angina. This condition represents a major global cardiovascular healthcare challenge, with patients experiencing chronic anginal symptoms that significantly impair their quality of life and for whom few effective treatments exist. The clinical burden of refractory angina is only set to grow because of improved survival from coronary artery disease, increased life expectancy and the presence of residual angina after percutaneous or surgical coronary revascularisation. Therefore, new, effective, evidence-based therapies are urgently needed. In this review, we highlight the unmet clinical needs of patients with refractory angina, discuss the development of the CSR device and review the preclinical and clinical evidence base underlying CSR implantation. In addition, we discuss the current role of CSR implantation in contemporary interventional practice, highlighting knowledge gaps and discussing areas of on-going research.

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

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

Coronary sinus reducer for the treatment of refractory angina (ORBITA-COSMIC): a randomised, placebo-controlled trial.

BACKGROUND: The coronary sinus reducer (CSR) is proposed to reduce angina in patients with stable coronary artery disease by improving myocardial perfusion. We aimed to measure its efficacy, compared with placebo, on myocardial ischaemia reduction and symptom improvement. METHODS: ORBITA-COSMIC was a double-blind, randomised, placebo-controlled trial conducted at six UK hospitals. Patients aged 18 years or older with angina, stable coronary artery disease, ischaemia, and no further options for treatment were eligible. All patients completed a quantitative adenosine-stress perfusion cardiac magnetic resonance scan, symptom and quality-of-life questionnaires, and a treadmill exercise test before entering a 2-week symptom assessment phase, in which patients reported their angina symptoms using a smartphone application (ORBITA-app). Patients were randomly assigned (1:1) to receive either CSR or placebo. Both participants and investigators were masked to study assignment. After the CSR implantation or placebo procedure, patients entered a 6-month blinded follow-up phase in which they reported their daily symptoms in the ORBITA-app. At 6 months, all assessments were repeated. The primary outcome was myocardial blood flow in segments designated ischaemic at enrolment during the adenosine-stress perfusion cardiac magnetic resonance scan. The primary symptom outcome was the number of daily angina episodes. Analysis was done by intention-to-treat and followed Bayesian methodology. The study is registered with ClinicalTrials.gov, NCT04892537, and completed. FINDINGS: Between May 26, 2021, and June 28, 2023, 61 patients were enrolled, of whom 51 (44 [86%] male; seven [14%] female) were randomly assigned to either the CSR group (n=25) or the placebo group (n=26). Of these, 50 patients were included in the intention-to-treat analysis (24 in the CSR group and 26 in the placebo group). 454 (57%) of 800 imaged cardiac segments were ischaemic at enrolment, with a median stress myocardial blood flow of 1·08 mL/min per g (IQR 0·77-1·41). Myocardial blood flow in ischaemic segments did not improve with CSR compared with placebo (difference 0·06 mL/min per g [95% CrI -0·09 to 0·20]; Pr(Benefit)=78·8%). The number of daily angina episodes was reduced with CSR compared with placebo (OR 1·40 [95% CrI 1·08 to 1·83]; Pr(Benefit)=99·4%). There were two CSR embolisation events in the CSR group, and no acute coronary syndrome events or deaths in either group. INTERPRETATION: ORBITA-COSMIC found no evidence that the CSR improved transmural myocardial perfusion, but the CSR did improve angina compared with placebo. These findings provide evidence for the use of CSR as a further antianginal option for patients with stable coronary artery disease. FUNDING: Medical Research Council, Imperial College Healthcare Charity, National Institute for Health and Care Research Imperial Biomedical Research Centre, St Mary's Coronary Flow Trust, British Heart Foundation.

Predictors of left ventricular ejection fraction in high-risk percutaneous coronary interventions.

Revascularization completeness after percutaneous coronary intervention (PCI) is associated with improved long-term outcomes. Mechanical circulatory support [intra-aortic balloon pump (IABP) or Impella] is used during high-risk PCI (HR-PCI) to enhance peri-procedural safety and achieve more complete revascularization. The relationship between revascularization completeness [post-PCI residual SYNTAX Score (rSS)] and left ventricular ejection fraction (LVEF) in HR-PCI has not been established. We investigated LVEF predictors at 90 days post-PCI with Impella or IABP support. Individual patient data (IPD) were analyzed from PROTECT II (NCT00562016) in the base case. IPD from PROTECT II and RESTORE-EF (NCT04648306) were naïvely pooled in the sensitivity analysis. Using complete cases only, linear regression was used to explore the predictors of LVEF at 90 days post-PCI. Models were refined using stepwise selection based on Akaike Information Criterion and included: treatment group (Impella, IABP), baseline characteristics [age, gender, race, New York Heart Association Functional Classification, LVEF, SYNTAX Score (SS)], and rSS. Impella treatment and higher baseline LVEF were significant predictors of LVEF improvement at 90 days post-PCI (p ≤ 0.05), and a lower rSS contributed to the model (p = 0.082). In the sensitivity analysis, Impella treatment, higher baseline LVEF, and lower rSS were significant predictors of LVEF improvement at 90 days (p ≤ 0.05), and SS pre-PCI contributed to the model (p = 0.070). Higher baseline LVEF, higher SS pre-PCI, lower rSS (i.e. completeness of revascularization), and Impella treatment were predictors of post-PCI LVEF improvement. The findings suggest potential mechanisms of Impella include improving the extent and quality of revascularization, and intraprocedural ventricular unloading.

Impact of Calcium Eccentricity on the Safety and Effectiveness of Coronary Intravascular Lithotripsy: Pooled Analysis From the Disrupt CAD Studies.

BACKGROUND: Coronary intravascular lithotripsy (IVL) safely facilitates successful stent implantation in severely calcified lesions. This analysis sought to determine the relative impact of lesion calcium eccentricity on the safety and effectiveness of IVL using high-resolution optical coherence tomography imaging. METHODS: Individual patient-level data (n=262) were pooled from 4 distinct international prospective studies (Disrupt CAD I, II, III, and IV) and analyzed by an independent optical coherence tomography core laboratory. IVL performance in eccentric versus concentric calcification was analyzed by dividing calcified lesions into quartiles (≤180° [most eccentric], 181°-270°, 271°-359°, and 360° [concentric]) by maximum continuous calcium arc. RESULTS: In the 230 patients with clear imaging field on optical coherence tomography, there were no differences in preprocedure minimum lumen area, diameter stenosis, or maximum calcium thickness. The calcium length and volume index increased progressively with increasing mean and maximum continuous calcium arc (ie, concentricity). Conversely, the minimum calcium thickness decreased progressively with increasing concentricity. Post-procedure, the number of calcium fractures, fracture depth, and fracture width increased with increasing concentricity, with a 4-fold increase in the number of fractures in lesions with 360° of calcium arc compared with ≤180°. This increase in IVL-induced calcium fracture with increasing calcium burden and concentricity facilitated stent expansion and luminal gain such that there were no significant differences across quartiles. CONCLUSIONS: IVL induced calcium fractures proportional to the magnitude of coronary artery calcium, including in eccentric calcium, leading to consistent improvements in stent expansion and luminal gain in both eccentric and concentric calcified coronary lesions.

Optical Coherence Tomography-Guided versus Angiography-Guided PCI.

BACKGROUND: Data regarding clinical outcomes after optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) as compared with angiography-guided PCI are limited. METHODS: In this prospective, randomized, single-blind trial, we randomly assigned patients with medication-treated diabetes or complex coronary-artery lesions to undergo OCT-guided PCI or angiography-guided PCI. A final blinded OCT procedure was performed in patients in the angiography group. The two primary efficacy end points were the minimum stent area after PCI as assessed with OCT and target-vessel failure at 2 years, defined as a composite of death from cardiac causes, target-vessel myocardial infarction, or ischemia-driven target-vessel revascularization. Safety was also assessed. RESULTS: The trial was conducted at 80 sites in 18 countries. A total of 2487 patients underwent randomization: 1233 patients were assigned to undergo OCT-guided PCI, and 1254 to undergo angiography-guided PCI. The minimum stent area after PCI was 5.72±2.04 mm2 in the OCT group and 5.36±1.87 mm2 in the angiography group (mean difference, 0.36 mm2; 95% confidence interval [CI], 0.21 to 0.51; P<0.001). Target-vessel failure within 2 years occurred in 88 patients in the OCT group and in 99 patients in the angiography group (Kaplan-Meier estimates, 7.4% and 8.2%, respectively; hazard ratio, 0.90; 95% CI, 0.67 to 1.19; P = 0.45). OCT-related adverse events occurred in 1 patient in the OCT group and in 2 patients in the angiography group. Stent thrombosis within 2 years occurred in 6 patients (0.5%) in the OCT group and in 17 patients (1.4%) in the angiography group. CONCLUSIONS: Among patients undergoing PCI, OCT guidance resulted in a larger minimum stent area than angiography guidance, but there was no apparent between-group difference in the percentage of patients with target-vessel failure at 2 years. (Funded by Abbott; ILUMIEN IV: OPTIMAL PCI ClinicalTrials.gov number, NCT03507777.).

Coronary Intravascular Lithotripsy for Treatment of Severely Calcified Lesions: Long-Term Sex-Specific Outcomes.

Background: Intravascular lithotripsy (IVL) for calcified lesion preparation prior to drug-eluting stent placement has high procedural success and safety, especially in women, whereas other atheroablative approaches are associated with increased procedural complications. We sought to investigate long-term sex-based outcomes of IVL-facilitated stenting. Methods: We performed a patient-level pooled analysis of the single-arm Disrupt CAD III and IV studies. Patient baseline, procedural characteristics, and outcomes were examined according to sex at 30 days and 1 year. The primary end point was major adverse cardiac events (a composite of cardiac death, all myocardial infarction, or target vessel revascularization). Target lesion failure was defined as cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization. Results: A total of 448 patients, 106 (24%) women, were included. Women were older and less likely to be smokers. Women had smaller reference vessel diameters (2.8 mm vs 3.1 mm), shorter lesion length (23.6 mm vs 27.1 mm), and shorter total calcified length (44.4 mm vs 49.3 mm) compared with men. Post-IVL angiographic outcomes and complications were similar between women and men. At 1 year, major adverse cardiac event rates (12.3% vs 13.2%, P = .52) were not different between women and men. There were no differences between women and men (10.4% vs 11.2%; P = .43) in target lesion failure at 1 year. Conclusions: Use of IVL in the treatment of severely calcified lesions is associated with low rates of adverse clinical events and with similar safety and effectiveness in women and men at 1 year.

Intravascular lithotripsy for treatment of calcific coronary lesions in ST elevation myocardial infarction.

AIMS: To describe the utility and safety of intravascular lithotripsy (IVL) in the setting of primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI). METHODS AND RESULTS: We performed a retrospective analysis, across six UK sites of all patients in whom IVL was used for coronary calcium modification of the culprit lesion during primary PCI for STEMI. The 72 patients were included. IVL was used in de-novo culprit lesions in 57 (79%) of cases and culprit in-stent restenoses in 11 (15%) of cases. In four cases (6%) it was used in a newly deployed stent when this was under-expanded due to inadequate calcium modification. Of the 30 cases in which intracoronary imaging was available for stent analysis, the average stent expansion was 104%. Intra-procedural stent thrombosis occurred in one case (1%), and no-reflow in three cases (4%). The 30 day MACE rates were 18%. CONCLUSION: IVL appears to be feasible and safe for use in the treatment of calcific coronary artery disease in the setting of STEMI.

Intravascular Lithotripsy for Treatment of Severely Calcified Coronary Lesions: 1-Year Results From the Disrupt CAD III Study.

Background: Coronary calcification impairs stent delivery and optimal expansion, a significant predictor of subsequent stent thrombosis and restenosis. Current calcium ablative technologies may be limited by guidewire bias and periprocedural complications. Intravascular lithotripsy (IVL) delivers acoustic pressure waves to modify calcium, enhance vessel compliance, and optimize stent deployment. The Disrupt CAD III study demonstrated high (92.4%) procedural success and low (7.8%) 30-day major adverse cardiac event (MACE) rates following IVL, but longer term follow-up is required to determine the durability of clinical benefit and the late impact of optimized stent implantation associated with IVL. This analysis evaluates 1-year outcomes from the Disrupt CAD III study. Methods: Disrupt CAD III (NCT03595176) was a prospective, single-arm approval study designed to assess the safety and effectiveness of IVL as an adjunct to coronary stenting in de novo, severely calcified coronary lesions (n = 384). MACE was defined as the composite of cardiac death, myocardial infarction (MI), or ischemia-driven target vessel revascularization; target lesion failure was defined as cardiac death, MI, or ischemia-driven target lesion revascularization (ID-TLR). Results: At 1 year, MACE occurred in 13.8% of patients (cardiac death: 1.1%, MI: 10.5%, ischemia-driven target vessel revascularization: 6.0%) and target lesion failure occurred in 11.9% (ID-TLR: 4.3%), both driven by non-Q-wave MI (9.2%). Stent thrombosis (definite or probable) occurred in 1.1% of patients (including 1 event [0.3%] beyond 30 â€‹days). Conclusions: Disrupt CAD III represents the largest long-term (1-year) analysis of coronary IVL to date. IVL treatment prior to coronary stent implantation in severely calcified lesions was associated with low 1-year rates of MACE, ID-TLR, and stent thrombosis.

Sex-Specific Outcomes After Coronary Intravascular Lithotripsy: A Patient-Level Analysis of the Disrupt CAD Studies.

Background: Coronary artery calcification increases the procedural complexity of percutaneous coronary intervention and is associated with worse outcomes, especially in women. Intravascular lithotripsy (IVL) has been demonstrated to be safe and effective for vessel preparation in severely calcified stenotic lesions before stent implantation. Sex-based outcomes of IVL-facilitated stenting have not been defined. Methods: We performed a patient-level pooled analysis of the 4 prospective, single-arm Disrupt CAD studies that evaluated the safety and efficacy of IVL-facilitated stenting. Patient baseline and procedural characteristics and clinical outcomes were examined based on sex. The primary safety end point was 30-day major adverse cardiovascular events, defined as the composite of cardiac death, myocardial infarction, or target vessel revascularization. The primary efficacy end point was procedural success, defined as stent delivery with residual in-stent stenosis ≤30% without in-hospital major adverse cardiovascular events. Results: A total of 628 patients were included, of which 144 (22.9%) were women. Women were older (P < .001) and more likely to have hyperlipidemia (P = .03), renal insufficiency (P = .05), and prior myocardial infarction (P = .05). Women had smaller mean reference vessel diameter (2.7 â€‹ ± â€‹0.4 â€‹mm vs 3.0 â€‹ ± â€‹0.5 â€‹mm, P < .001), shorter lesion length (22.4 â€‹ ± â€‹10.3 â€‹mm vs 25.0 â€‹ ± â€‹11.7 â€‹mm, P = .01), and less side branch involvement (22.9% vs 32.4%, P = .03). Severe coronary calcification defined by angiography, stent delivery success, lesion predilatation, post-IVL dilatation, and poststent dilatation was similar between groups. There were no significant differences between women and men in the primary safety end point (8.3% vs 7.1%, P = .61; adjusted odds ratio 1.66; 95% confidence interval 0.78, 3.34; P = .17) or the primary efficacy end point (91.7% vs 92.6%, P = .72; adjusted odds ratio 0.58; 95% confidence interval 0.29, 1.24; P = .15). Post-IVL serious angiographic complications (flow-limiting dissection, perforation, abrupt closure, slow flow, no reflow) were similar for women and men (1.6% vs 2.3%, P = .75). Conclusions: Despite more comorbidities and smaller vessel size, IVL-facilitated stenting of severely calcified lesions achieves similar safety and efficacy in women and men.

Principles of Intravascular Lithotripsy for Calcific Plaque Modification.

A significant proportion of lesions treated with transcatheter interventions in the coronary and peripheral vascular beds exhibit moderate to severe calcific plaques known to portend lower procedural success rates, increased peri-procedural adverse events, and unfavorable clinical outcomes compared with noncalcific plaques. Adapted from lithotripsy technology used for treatment of ureterorenal calculi, intravascular lithotripsy (IVL) is a novel technique for the treatment of severely calcific plaque lesions that uses acoustic shockwaves in a balloon-based delivery system. Shockwaves induce calcium fractures, which facilitate stent expansion and luminal gain. In this review, the authors summarize the physics, preclinical and clinical data on IVL use in the coronary and peripheral vasculature, and future directions of IVL in transcatheter cardiovascular therapies.

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

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

Therapeutic Approach to Calcified Coronary Lesions: Disruptive Technologies.

PURPOSE OF REVIEW: Moderate or severe calcification is present in approximately one third of coronary lesions in patients with stable ischemic heart disease and acute coronary syndromes and portends unfavorable procedural results and long-term outcomes. In this review, we provide an overview on the state-of-the-art in evaluation and treatment of calcified coronary lesions. RECENT FINDINGS: Intravascular imaging (intravascular ultrasound or optical coherence tomography) can guide percutaneous coronary intervention of severely calcified lesions. New technologies such as orbital atherectomy and intravascular lithotripsy have significantly expanded the range of available techniques to effectively modify coronary calcium and facilitate stent expansion. Calcium fracture improves lesion compliance and is essential to optimize stent implantation. Intravascular imaging allows for detailed assessment of patterns and severity of coronary calcium that are integrated into scoring systems to predict stent expansion, identifying which lesions require atherectomy for lesion modification. Guided by intravascular imaging, older technologies such as rotational atherectomy and excimer laser can be incorporated with newer technologies such as orbital atherectomy and intravascular lithotripsy into an algorithmic approach for the safe and effective treatment of patients with heavily calcified coronary lesions.

Definitions and Clinical Trial Design Principles for Coronary Artery Chronic Total Occlusion Therapies: CTO-ARC Consensus Recommendations.

Over the past 2 decades, chronic total occlusion (CTO) percutaneous coronary intervention has developed into its own subspecialty of interventional cardiology. Dedicated terminology, techniques, devices, courses, and training programs have enabled progressive advancements. However, only a few randomized trials have been performed to evaluate the safety and efficacy of CTO percutaneous coronary intervention. Moreover, several published observational studies have shown conflicting data. Part of the paucity of clinical data stems from the fact that prior studies have been suboptimally designed and performed. The absence of standardized end points and the discrepancy in definitions also prevent consistency and uniform interpretability of reported results in CTO intervention. To standardize the field, we therefore assembled a broad consortium comprising academicians, practicing physicians, researchers, medical society representatives, and regulators (US Food and Drug Administration) to develop methods, end points, biomarkers, parameters, data, materials, processes, procedures, evaluations, tools, and techniques for CTO interventions. This article summarizes the effort and is organized into 3 sections: key elements and procedural definitions, end point definitions, and clinical trial design principles. The Chronic Total Occlusion Academic Research Consortium is a first step toward improved comparability and interpretability of study results, supplying an increasingly growing body of CTO percutaneous coronary intervention evidence.

Safety and effectiveness of coronary intravascular lithotripsy in eccentric calcified coronary lesions: a patient-level pooled analysis from the Disrupt CAD I and CAD II Studies.

BACKGROUND: The aim of this study was to assess the safety and effectiveness of intravascular lithotripsy (IVL) in treating eccentric calcified coronary lesions. METHODS: Between December 2015 and March 2019, 180 patients were enrolled in the Disrupt CAD I and CAD II studies across 19 sites in 10 countries. Patient-level data were pooled from these two studies (n = 180), within which 47 eccentric lesions (26%) and 133 concentric lesions were identified. RESULTS: Clinical success, defined as residual stenosis < 50% after stenting and no in-hospital MACE, was similar between the eccentric and concentric cohorts (93.6% vs. 93.2%, p = 1.0). There were no perforations, abrupt closure, slow flow or no reflow events observed in either group, and there were low rates of flow-limiting dissections (Grade D-F: 0% eccentric, 1.7% concentric; p = 0.54). Final acute gain and percent residual stenosis were similar between the two groups. Final residual stenosis of 8.6 ± 9.8% in eccentric and 10.0 ± 9.0% (p = 0.56) in concentric stenosis confirms the significant effect of IVL in calcified coronary lesions. CONCLUSION: In this first report from a pooled patient-level analysis of coronary IVL from the Disrupt CAD I and CAD II studies, IVL use was associated with consistent improvement in procedural and clinical outcomes in both eccentric and concentric calcified lesions.

Optical coherence tomography-guided coronary stent implantation compared to angiography: a multicentre randomised trial in PCI - design and rationale of ILUMIEN IV: OPTIMAL PCI.

AIMS: Randomised trials have demonstrated improvement in clinical outcomes with intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI. The ILUMIEN III trial demonstrated non-inferiority of an optical coherence tomography (OCT)- versus IVUS-guided PCI strategy in achieving similar post-PCI lumen dimensions. ILUMIEN IV is a large-scale, multicentre, randomised trial designed to demonstrate the superiority of OCT- versus angiography-guided stent implantation in patients with high-risk clinical characteristics (diabetes) and/or complex angiographic lesions in achieving larger post-PCI lumen dimensions and improving clinical outcomes. METHODS AND RESULTS: ILUMIEN IV is a prospective, single-blind clinical investigation that will randomise between 2,490 and 3,656 patients using an adaptive design to OCT-guided versus angiography-guided coronary stent implantation in a 1:1 ratio. The primary endpoints are: (1) post-PCI minimal stent area assessed by OCT in each randomised arm, and (2) target vessel failure, the composite of cardiac death, target vessel myocardial infarction, or ischaemia-driven target vessel revascularisation. Clinical follow-up will continue for up to two years. The trial is currently enrolling, and the principal results are expected in 2022. CONCLUSIONS: The large-scale ILUMIEN IV randomised controlled trial will evaluate the effectiveness of OCT-guided versus angiography-guided PCI in improving post-PCI lumen dimensions and clinical outcomes in patients with diabetes and/or with complex coronary lesions. TRIAL REGISTRATION: NCT03507777.