Minimal Lumen Diameter Research Articles

Percutaneous reintervention on aortic coarctation stenting.

The aim of this study was to assess the efficacy and safety of percutaneous reintervention in patients who underwent aortic coarctation stenting at an early age. From 1993 to 2018, 177 patients with aortic coarctation were treated with stent implantation at our centre; 33 of them were treated at less than 12 years of age and required reintervention because of their rate of growth. The average age of the patients at the first and second procedure was 6±3 years and 19±7 years, respectively. At the reintervention procedure, 15 (45%) patients were treated with balloon re-expansion, and 18 (55%) were treated with re-stenting. Success was obtained in 30 patients (91%). The gradient across the coarctation changed from 22±10 mmHg to 6±6 mmHg, while the minimal lumen diameter increased from 9±6 mm to 15±3 mm. There were eight occlusions of the femoral artery (after the first procedure), and two covered stents were needed because of femoral bleeding. The mean follow-up time after the second procedure was 5±4 years. A third procedure was required only in three patients (9%). Patients with aortic coarctation treated with stent placement at an early age can be successfully re-treated after the completion of their somatic growth.

A comparison between drug-eluting stent implantation and drug-coated balloon angioplasty in patients with left main bifurcation in-stent restenotic lesions

BackgroundThe current guidelines recommend both repeat stenting and drug-coated balloons (DCB) for in-stent restenosis (ISR) lesions, if technically feasible. However, real-world clinical data on the interventional strategies in patients with left main bifurcation (LMB)-ISR have not been elucidated.MethodsSeventy-five patients with LMB-ISR, who underwent percutaneous coronary intervention (PCI) between January 2009 and July 2015, were retrospectively reviewed for the present study (repeat drug eluting stent [DES] implantation [n = 51], DCB angioplasty [n = 24]).ResultsAnalysis of the baseline characteristics showed that the patients in the DCB group had a lower incidence of non-ST segment elevation myocardial infarction/ST segment elevation myocardial infarction at the index PCI (8.3% vs. 25.5%; p = 0.12), higher low-density lipoprotein-cholesterol level (92.9 mg/dL vs. 81.7 mg/dL; p = 0.09), and more “stent-in-stent” lesions (25% vs. 7.8%; p = 0.07) than those in the DES group. A smaller post-procedural minimal target lesion lumen diameter was also noted in the DCB group than in the DES group (2.71 mm vs. 2.85 mm; p = 0.03). The cumulative incidence rates of major adverse cardiac events (MACEs) were similar between both groups (median follow-up duration, 868 days; MACE rate, 25% in the DCB group vs. 25.5% in the DES group; p = 0.96). The multivariate Cox regression analysis indicated that the true bifurcation of ISR was an independent risk predictor of MACEs (hazard ratio, 4.62; 95% confidence interval, 1.572–13.561; p < 0.01).ConclusionsDES and DCB showed comparable long-term clinical results in patients with LMB-ISR lesions.

The Functional Severity Assessment of Coronary Stenosis Using Coronary Computed Tomography Angiography-Based Myocardial Mass at Risk and Minimal Lumen Diameter.

Background We investigated whether or not the addition of myocardial mass at risk (MMAR) to quantitative coronary angiography was useful for diagnosing functionally significant coronary stenosis in the daily practice. Methods We retrospectively enrolled 111 consecutive patients with 149 lesions who underwent clinically indicated coronary computed tomography angiography and subsequent elective coronary angiography with fractional flow reserve (FFR) measurement. MMAR was calculated using a workstation-based software program with ordinary thin slice images acquired for the computed tomography, and the minimal lumen diameter (MLD) and the diameter stenosis were measured with quantitative coronary angiography. Results The MLD and MMAR were significantly correlated with the FFR, and the MMAR-to-MLD ratio (MMAR/MLD) showed a good correlation. The area under the receiver operating characteristic curve (AUC) of MMAR/MLD for FFR ≤ 0.8 was 0.746, and the sensitivity, specificity, positive predictive value, and negative predictive value were 60%, 83%, 68%, and 77%, respectively, at a cut-off value of 29.5 ml/mm. The addition of MMAR/MLD to diameter stenosis thus made it possible to further discriminate lesions with FFR ≤ 0.8 (AUC = 0.750). For the proximal left coronary artery lesions, in particular, MMAR/MLD showed a better correlation with the FFR, and the AUC of MMAR/MLD for FFR ≤ 0.8 was 0.919 at a cut-off value of 31.7 ml/mm. Conclusions The index of MMAR/MLD correlated well with the physiological severity of coronary stenosis and showed good accuracy for detecting functional significance. The MMAR/MLD might be a useful parameter to consider when deciding the indication for revascularization.

Diagnostic performance of intracoronary optical coherence tomography-based versus angiography-based fractional flow reserve for the evaluation of coronary lesions.

The aim of this study was to evaluate the diagnostic performance of OCT-based optical flow ratio (OFR) in unselected patients and compare it with angiography-based quantitative flow ratio (QFR), using wire-based FFR as reference standard. All patients with OCT and FFR assessment prior to revascularisation were analysed. OFR and QFR were computed in a blinded fashion and compared with FFR, applying the same cut-off value of ≤0.80 to all to define ischaemia. Paired comparison between OFR and QFR was performed in 212 vessels from 181 patients. Average FFR was 0.82±0.10 and 40.1% of vessels had an FFR ≤0.80. OFR showed a significantly better correlation and agreement with FFR than QFR (r=0.87 versus 0.77, p<0.001; SD of the difference=0.05 versus 0.07, p<0.001). The AUC was 0.97 for OFR, higher than for QFR (difference=0.05, p=0.017), and much higher than the minimal lumen area (difference=0.15, p<0.001) and diameter stenosis (difference=0.17, p<0.001). Diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio for OFR to identify FFR ≤0.80 were 92%, 86%, 95%, 92%, 91%, 18.2 and 0.2, respectively. The diagnostic accuracy of OFR was not significantly different in MI-related vessels (95% versus 90%, p=0.456), or in vessels with and without previously implanted stents (90% versus 93%, p=0.669). OFR had an excellent agreement with FFR in consecutive patients with coronary artery disease. OFR was superior to QFR, and much better than conventional morphological parameters in determining physiological significance of coronary stenosis. The diagnostic performance of OFR was not influenced by the presence of prior myocardial infarction or implanted stents.

Drug-Coated Balloons versus Everolimus-Eluting Stents in Patients with In-Stent Restenosis: A Pair-Wise Meta-Analysis of Randomized Trials.

Objective This study aimed to compare the effectiveness of drug-coated balloons (DCB) with everolimus-eluting stents (EES) in the treatment of in-stent restenosis (ISR) and the differential relative effect of DCB in patients with drug-eluting stents (DES)-ISR and bare metal stents (BMS)-ISR. Background The efficiency and safety of DCB and EES need to be assessed for the treatment of ISR. Methods A systematic literature search was conducted using PubMed and EMBASE to identify all relevant studies. Angiographic results and clinical events were separately assessed. Subgroup meta-analyses were performed according to the type of restenosed stent. Results Six randomized trials with 1134 patients were included. The overall pooled outcomes indicated that DCB was associated with lower minimum lumen diameter (mean difference (MD) = −0.17, 95% CI = −0.29 to −0.05, P = 0.006) and higher target lesion revascularization (risk ratio (RR) = 2.38, 95% CI = 1.36 to 4.18, P = 0.002) than EES. However, the subgroup meta-analyses showed that DCB was inferior to EES only in DES-ISR patients, with lower minimum lumen diameter (MD = −0.25, 95% CI = −0.37 to −0.14, P < 0.001), higher percent diameter stenosis (MD = 5.37, 95% CI = 1.33 to 9.42, P = 0.009), more binary restenosis (RR = 2.07, 95% CI = 1.20 to 3.58, P = 0.009), and higher incidence of target vessel revascularization (RR = 2.07, 95% CI = 1.22 to 3.50, P = 0.007) and target lesion revascularization (RR = 2.43, 95% CI = 1.28 to 4.22, P = 0.002). No differences in angiographic results and clinical events were found between DCB and EES in BMS-ISR patients. Conclusions DCB was inferior to EES in DES-ISR and comparable in BMS-ISR in terms of angiographic results and clinical events.

Relation of Plasma Xanthine Oxidoreductase Activity to Coronary Lipid Core Plaques Assessed by Near-Infrared Spectroscopy Intravascular Ultrasound in Patients With Stable Coronary Artery Disease

Previous studies reported that elevated serum uric acid level was associated with greater coronary lipid plaque. Xanthine oxidoreductase (XOR) is a rate-limiting enzyme in purine metabolism and is believed to play important roles in coronary atherosclerosis. However, the relation between XOR and coronary lipid plaque is unclear. Patients with stable coronary artery disease who underwent elective percutaneous coronary intervention under near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) guidance were prospectively included. They were divided into 3 groups according to plasma XOR activities based on a previous report: low, normal, and high. Quantitative coronary angiography and gray-scale IVUS were analyzed. The primary end point was coronary lipid plaques in a nontarget vessel assessed by NIRS-IVUS with lipid core burden index (LCBI) and maximum LCBI in 4 mm (maxLCBI4mm). Out of 68 patients, 26, 31, and 11 patients were classified as low, normal, and high XOR activity groups. Quantitative coronary angiography demonstrated that the high XOR activity group had longer lesion length, smaller minimum lumen diameter, and higher percentage of diameter stenosis in a nontarget vessel among the 3 groups. Gray-scale IVUS analysis also showed smaller lumen area in the high XOR activity group than the others. LCBI (102.1 ± 56.5 vs 65.6 ± 48.5 vs 55.6 ± 37.8, p = 0.04) and maxLCBI4mm (474.4 ± 171.6 vs 347.4 ± 181.6, 294.0 ± 155.9, p = 0.04) in a nontarget vessel were significantly higher in the high XOR group than in the normal and low groups. In conclusion, elevated XOR activity was associated with coronary lipid-rich plaque in a nontarget vessel in patients with stable coronary artery disease.

First-in-man study of a thinner-strut sirolimus-eluting bioresorbable scaffold (FUTURE-I): Three-year clinical and imaging outcomes.

The FUTURE-I study aimed to assess preliminary safety and effectiveness with the long-term clinical and imaging follow-up for the Firesorb (MicroPort, Shanghai, China), a thinner-strut sirolimus-eluting bioresorbable scaffold (BRS). First-generation BRS has been associated with unexpected device-related adverse outcomes at long-term follow-up. In this prospective, open-label, first-in-man study, patients with single de novo lesions in native coronary arteries were randomized 2:1 into two cohorts after successful Firesorb implantation: cohort 1 (n = 30) underwent multimodality imaging assessment at 6 and 24 months; and cohort 2 (n = 15) at 12 and 36 months. All patients underwent clinical follow-up at 1, 6, and 12 months and annually up to 5 years. Between January and March 2016, 45 patients were enrolled. At 3-year follow-up, one patient had experienced target lesion failure and none scaffold thrombosis. In-scaffold minimal lumen diameter decreased significantly from 6-month to 2-year (2.53 ± 0.24 mm vs. 2.27 ± 0.37 mm, p = .0003), and only numerically from 1-year to 3-year follow-up (2.48 ± 0.28 mm vs. 2.22 ± 0.13 mm, p = .08). By optical coherence tomography, neointimal strut coverage at 3-year follow-up was 99.8%, and very low rate of late scaffold discontinuity was observed, only in one patient on two cross sections with three malapposed struts. At 3-year follow-up of the FUTURE-I study, implantation of the thinner-strut Firesorb BRS appeared preliminary feasible and effective in the treatment of patients with noncomplex coronary lesions.

Risk Factors for Closure Failure following Percutaneous Transfemoral Transcatheter Aortic Valve Implantation

The percutaneous access site of transfemoral transcatheter aortic valve implantation (TAVI) procedures is commonly closed using a preclosure technique with suture-type closure devices. We sought to evaluate the predictors and outcomes of percutaneous closure device (PCD) failure during transfemoral TAVI. This single-center retrospective analysis included 184 patients who underwent transfemoral TAVI using 2 ProGlide sutures for severe aortic stenosis between July 2011 and September 2018. PCD failure was observed in 11.4%. The causes of PCD failure included 5 cases of insufficient hemostasis, 13 cases of arterial stenosis or occlusion, and 3 cases of dissection. Closure failures were managed by surgical repair in 10 patients and endovascular treatment in 11 patients. In a multivariate binary logistic model, a minimum lumen diameter of the common femoral artery (CFA) (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.15-0.83, P=0.017) and left femoral access (OR 2.89, 95% CI 1.01-8.30, P=0.048) was identified as a predictor of PCD failure. PCD failure was not associated with increased mortality (0% vs. 2.5%, P=1.000) or a major adverse cardiovascular event (MACE; 4.8% vs. 4.3%, P=1.000) at 30days. PCD failures were not uncommon in patients undergoing percutaneous transfemoral TAVI. Small CFA diameter and left femoral access are predictors of PCD failure. However, PCD failures were not associated with increased mortality or MACE.

309 Computed Tomography Coronary Angiography for the Assessment of Left Main Coronary Artery Stenosis

Angiographic assessment of left main coronary artery (LMCA) stenosis is challenging. When uncertainty exists, intravascular ultrasound (IVUS) minimal lumen area (MLA) ≥6 mm2 is used as safe threshold for deferral of revascularization. With emergence of Computed Tomography Coronary Angiography (CTCA) as a first-line investigation, we sought to assess which quantitative CT-measure best compared with current IVUS standards. Patients who underwent both IVUS and CTCA assessment of angiographically intermediate LMCA stenosis (n=48) were included. All CTCA were performed <90 days prior to IVUS. The cohort was divided into those with significant (S-LMCA) versus non-significant (NS-LMCA) disease, using IVUS ≥6 vs <6 mm2. Mean age (60.3±12.4 vs 59.9±11.9yrs, p=0.91) and % male (57.7% vs 54.6%, p=0.83) were similar between groups. Mean time from CTCA to IVUS assessment was 17.4±19.8 days, with mean QCA stenosis severity of 46.0±18.6%. On CTCA, patients with NS-LMCA had significantly higher luminal area (8.3±3.8 vs 5.2±1.6 mm2, p=0.005), minimal lumen diameter (MLD) (3.2±0.7 vs 2.5±0.4 mm, p<0.001), with similar luminal volumes (99.9±50.5 vs 113.5±73.9 mm3, p=0.47). There was a significant positive correlation between CTCA and IVUS MLA (r=0.77, p <0.001) and MLD (r=0.73, p<0.001). ROC analysis demonstrated CTCA MLA <8.29 mm2 had the best diagnostic accuracy for predicting IVUS MLA <6 mm2 (area under the curve=0.76, sensitivity=100%, specificity=54% p=0.002). CTCA luminal measures correlate well with IVUS within the LMCA. These results suggest that CTCA measures could potentially be used to safely defer revascularisation for LMCA disease.

Clinical and angiographic factors predicting fractional flow reserve and explaining the visual-functional mismatch in patients with intermediate coronary artery stenosis.

Visual-functional mismatch between coronary angiography and fractional flow reserve (FFR) has been reported, and the underlying reason remains poorly understood. Therefore, the relationship between angiographic measurements and FFR was evaluated, and predictors for FFR in intermediate coronary artery stenosis were determined. Consecutive 314 patients (405 lesions) with a lesion of 30-80% angiographic diameter stenosis who underwent invasive FFR were recruited. The myocardial area supplied by the coronary artery distal to the stenosis was evaluated using a modified version of the Bypass Angioplasty Revascularization Investigation (BARI) score. Participants underwent follow-up, and major cardiovascular events (MACE), including all-cause death, myocardial infarction (MI), and unplanned revascularization were recorded. Although % diameter stenosis was correlated with FFR (R = 0.279, P < 0.001), diameter stenosis-FFR mismatch was observed in 37.8% of the lesions. Although FFR values were not associated with clinical factors, such as age, sex, and comorbidities, it was correlated with minimal lumen diameter (MLD), diffuse lesion, presence of proximal lesion, and BARI score. In addition, the lesions in left anterior descending (LAD) coronary artery showed low FFR values compared with those in the left circumflex coronary artery or right coronary artery. In multivariate logistic analysis, MLD (β coefficient = 0.330), diffuse lesion (β coefficient = -0.266), proximal lesion (β coefficient = -0.144), BARI score (β coefficient = -0.219), and LAD lesion (β coefficient = -0.293) were all independent predictors for FFR value. The estimated FFR value based on these factors showed smaller mismatch and higher sensitivity. No difference was observed in the event rates for MACE and MI or revascularization between the FFR-guided and estimated FFR-guided strategies. MLD, diffuse lesion, proximal lesion, BARI score, and lesion vessel were independent predictors for FFR in intermediate coronary stenosis. Not only the extent of local lesion stenosis but also the amount of myocardial supply and the lesion location may determine the physiological significance and explain the visual-functional mismatch. The estimation of FFR by these factors may be useful in clinical practice.

Efficacy and Safety of TurboHawk Plaque Rotation Combined With Drug-coated Balloon in Treating Diabetic Patients With Lower Extremity Arterial Disease.

To evaluate the efficacy and safety of TurboHawk plaque rotation system combined with drug-coated balloon in treating lower extremity arterial disease (LEAD) of diabetes patients, a total of 145 diabetic patients with LEAD from March 2015 to September 2016 were recruited in our study. Lower extremity arterial disease was diagnosed by ultrasound and CT angiography (CTA). According to the surgical method, 65 cases underwent TurboHawk plaque rotation combined with drug-coated balloon (group A), 80 cases underwent simple drug-coated balloon expansion (group B). The characteristics of lesion, function test, ankle-brachial index (ABI), and postoperative complications were analyzed. All the patients were followed up at 1, 3, 6, 12, and 24 months after operation. At baseline, there was no difference in all the characteristics between the 2 groups. The early postoperation minimum lumen diameter (MLD), lumen stenosis rate, and ABI in 2 groups both improved. As the follow-up time increased, patients in group A had significantly higher MLD and ABL value, as well as lower level of lumen stenosis rate, restenosis rate, late lumen loss, and target lesion revascularization (all P < .05). Accordingly, functional testing revealed the 6-minute walk distance, 6-minute claudication distance, resting ABI, and post-exercise ABI in group A were significantly higher than those in group B (all P < .05). Besides, major graft reintervention (4.62% vs 11.25%) and major adverse limb events (6.15% vs 12.5%) in group A occurred less frequently than group B (all P < .05). In conclusion, the long-term effect of the combined approach was better than only drug-coated balloon in LEAD in Chinese diabetes patients.

Optical coherence tomography versus intravascular ultrasound in patients with myocardial infarction: a diagnostic performance study of pre-percutaneous coronary interventions.

Accurate coronary measurements are important in guiding percutaneous coronary intervention. Intravascular ultrasound is a widely accepted diagnostic modality for coronary measurement before percutaneous coronary intervention. The spatial resolution of optical coherence tomography is 10 times larger than that of intravascular ultrasound. The objective of the study was to compare quantitative and qualitative parameters of frequency domain optical coherence tomography (FDOCT) with those of intravascular ultrasound and coronary angiography in patients with acute myocardial infarction. Diagnostic parameters of coronary angiography, intravascular ultrasound, and FDOCT of 250 patients with coronary artery disease who required admission diagnosis were included in the analyses. Minimum lumen diameter detected by FDOCT was larger than that detected by quantitative coronary angiography (2.11±0.1 vs 1.89±0.09 mm, P<0.0001, q=34.67) but smaller than that detected by intravascular ultrasound (2.11±0.1 vs 2.19±0.11 mm, P<0.0001, q=12.61). Minimum lumen area detected by FDOCT was smaller than that detected by intravascular ultrasound (3.41±0.01 vs 3.69±0.01 mm2, P<0.0001). FDOCT detected higher numbers of thrombus, tissue protrusion, dissection, and incomplete stent apposition than those detected by intravascular ultrasound (P<0.0001 for all). More accurate and sensitive results of the coronary lumen can be detected by FDOCT than coronary angiography and intravascular ultrasound (level of evidence: III).

Dynamic Imaging Features of Retrospective Cardiac Gating CT Angiography Influence Delayed Adverse Events in Acute Uncomplicated Type B Aortic Dissections.

To investigate the correlation between dynamic morphological parameters of retrospective cardiac gating CT angiography (CTA) and delayed adverse event (DAE) in uncomplicated type B acute aortic dissection (uTB-AAD) patients. Eighty-seven patients initially diagnosed with uTB-AAD were retrospectively reviewed. Dynamic variables obtained by dose-regulated retrospective CTA were recorded, including the minimum relative true lumen diameter (RTLAmin), ratio of the minimum to maximum true lumen relative area (r-RTLA), the maximum diameter of the descending aorta, false lumen, and primary entry tear. Outcome analysis comprised incidences of DAE and early mortality within 3 to 14days since symptom occurring. Twenty-six patients (29.9%) developed DAE, and two of which (7.7%) died before any interventions. Smaller values of RTLAmin (P = 0.01) and r-RTLA at the upper thoracic descending aorta (UTDA) (P < 0.001), and r-RTLA at the renal artery level (P = 0.016) demonstrated higher incidences of DAE; maximum diameter of the descending aorta (P < 0.001), the false lumen (P = 0.008), and entry tear size (P = 0.007) were positively associated with the occurrence of DAE. r-RTLA at the UTDA level yielded the highest diagnostic accuracy (82.0%) in detecting DAE at an optimal cutoff value of 61.7% (AUC = 0.839). Performance of dynamic characteristics was superior to static features obtained from single-phase image in the detection of DAE (P < 0.001). Dynamic morphological features of retrospective cardiac gating CTA might aid in identifying a high risk of DAE in uTB-AAD patients and guiding early targeted interventions.

Intravascular Lithotripsy in Calcified Coronary Lesions: A Prospective, Observational, Multicenter Registry.

Optimal plaque preparation of calcified coronary lesions is key to prevent stent failure. The purpose of this study was to determine the strategy success and safety of intravascular lithotripsy (IVL) in calcified lesions of an all-comers cohort. Patients with calcified coronary lesions were screened in 3 centers. Seventy-one patients were eligible for IVL. Patients were assigned to (group A) primary IVL therapy for patients with calcified de-novo lesions (n=39 lesions), (group B) secondary IVL therapy for patients with calcified lesions in which noncompliant balloon dilatation failed (n=22 lesions), and (group C) tertiary IVL therapy in patients with stent underexpansion after previous stenting (n=17 lesions). Primary end point was strategy success (stent expansion with <20% in-stent residual stenosis) and safety outcomes (procedural complications, in-hospital major adverse cardiovascular event). Seventy-eight calcified lesions were treated using the Shockwave C2 balloon. Mean diameter stenosis of calcified lesions was 71.8±13.1% at baseline, decreased to 45.1±17.4% immediately after IVL, and to 17.5±15.2% after stenting. Mean minimal lumen diameter was 1.01±0.49 mm at baseline and increased to 1.90±0.61 after IVL, and to 2.88±0.56 mm after stenting. The primary end point of strategy success was reached in 84.6% (group A), 77.3% (group B), and 64.7% (group C). Device delivery and IVL treatment were possible in all lesions. Four type b dissections were observed without further sequelae. No patient suffered from in-hospital major adverse cardiovascular event. Seven Shockwave balloons ruptured during treatment without any sequelae. IVL provides a valid strategy for lesion preparation in severely calcified coronary lesions with high success rate, low procedural complications, and low major adverse cardiovascular event rates.

P2703Impact of subtended myocardial mass on the assessment of functional ischemia as evaluated by FFR and QFR

Abstract Background The fractional flow reserve (FFR) becomes a standard practice for revascularization decision-making in evaluating the functional significance of angiographically intermediate epicardial coronary stenosis. The quantitative flow ratio (QFR) is a novel method for rapid computational estimation of FFR without pressure wire and hyperemic induction. FFR has been reported to be associated with not only epicardial stenosis but also subtended myocardial mass (Vsub). In contrast, the relationship between QFR and Vsub has not been clarified. Purpose We sought to examine if subtended myocardial mass (Vsub) assessed by coronary computed tomography showed a significant relationship with QFR in comparison with FFR. Methods and results We performed a post-hoc analysis of 152 territories (LAD 116, RCA 25 and LCX 11 lesions) with angiographically intermediate-to-severe stenosis in 152 patients who underwent FFR assessment. The median FFR and QFR values were 0.76 (0.64–0.84) and 0.76 (0.72–0.83), respectively. The median diameter stenosis (%DS) and minimum lumen diameter (MLD) were 54.5 (43.9–64.2) and 1.2 (0.9–1.6), respectively. In total, 123 (80.9%) and 29 (19.1%) lesions showed concordant and discordant FFR and QFR functional classifications, respectively. The ability of Vsub/MLD2 to discriminate lesions with FFR≤0.80 and QFR≤0.80 was assessed compared with QCA data. FFR values were associated with Vsub (R=0.37, P&lt;0.001). In contrast, a trend albeit no significant linear relationshipwas detected between QFR and Vsub (R=0.15, P=0.060). The area under the curve (AUC) of Vsub/MLD2 predicting FFR≤0.80 (0.88: 95% confidence interval [CI], 0.83–0.94)was significantly better than that of MLD (0.80: 95% [CI], 0.72–0.88) (P&lt;0.001). On the other hand, the AUC of Vsub/MLD2 predicting QFR≤0.80 (0.82: 95% [CI], 0.75–0.90) was similar to that of MLD (0.80: 95% [CI], 0.72–0.87) (P=0.276). Multivariate analysis showed that the value of Vsub/MLD2 was an independent predictor of FFR≤0.80 (odds ratio [OR]: 1.09, 95% [CI]: 1.03–1.15, P=0.002), whereas it was not an independent predictor of QFR≤0.80. Conclusions Subtended cardiac mass volume derived from CT segmentation improved the diagnostic performance of angiography-derived parameters to identify ischemia-producing lesions when FFR used as a reference standard, whereas QFR showed non-significant relationship with subtended cardiac mass.

P6393Differences in coronary inflammation between the culprit and non-culprit vessels assessed by fat attenuation index on computed tomography in patients with acute coronary syndromes

Abstract Background Inflammation is linked with progression of coronary atherosclerosis. Recent studies have reported the association between elevated perivascular fat attenuation index (FAI) on computed tomography (CT) and worse cardiac outcomes in patients with coronary artery disease. Purpose We aimed to investigate the differences in FAI-defined peri-coronary inflammation status between the culprit and non-culprit vessels in patients with acute coronary syndromes (ACS). Methods A total of 78 ACS patients with left anterior descending coronary arteries (LAD) as a culprit vessel who underwent coronary CT angiography and invasive coronary angiography were studied. Proximal 40-mm segments of the LAD and the right coronary artery (RCA) were traced. Coronary inflammation was assessed by the FAI defined as the mean CT attenuation value of perivascular adipose tissue (−190 to −30 Hounsfield units [HU]) in a layer of tissue within a radial distance from the outer coronary artery wall equal to the diameter of the vessel. All patients were divided into two groups according to the values of FAI in the LAD: high FAI group (FAI-LAD &gt; median; n=39) and low FAI group (FAI-LAD ≤ median; n=39). Patient characteristics, angiographic and CT findings were compared between the two groups. Results In a total of 78 patients, median FAI in the LAD was −70.20 (interquartile range, −74.81 to −64.58) HU. High FAI group was associated with male sex and lower left ventricular ejection fraction compared with Low FAI group. Minimal lumen diameter, reference diameter, diameter stenosis, and lesion length on quantitative coronary angiography analysis and coronary artery calcium score on CT was not different between the groups. FAI in the RCA was also higher in High FAI group than that in Low FAI group (−67.64±8.31 vs. −76.47±6.25 HU, P&lt;0.001). Paired t-test comparison demonstrated that culprit vessel showed higher FAI than the non-culprit vessel (−69.85±7.74 vs. −72.11±8.54 HU, P=0.013). Conclusions In ACS patients with culprit LAD lesions, FAI-defined peri-coronary inflammation status is higher in the culprit vessel than in the non-culprit vessel.

P6171Role of myocardial mass for identifying FFR-verified ischemia and determining therapeutic strategy

Abstract Background Conventional noninvasive approach using coronary CT angiography (CTA) focusing on only coronary artery lesions remains mismatch in identifying functional ischemia and determining indication for coronary revascularization. Purpose We aimed to assess the usefulness of CT-verified myocardial mass for identifying FFR-verified myocardial ischemia and determining the indication of coronary revascularization after FFR examination. Methods We examined 244 vessels with intermediate stenoses (50 to 90% stenosis visually on CTA) in 216 patients (mean age 69.2±9.2, 166 men) who underwent both coronary CTA and invasive FFR. In addition to coronary stenosis severity and plaque characteristics on visual, minimal lumen diameter (MLD), minimal lumen area (MLA), plaque volume, the entire myocardial volume of the target vessel (MTV) and that exposed to ischemia (FFR ≤0.80) (myocardial volume of ischemia: MVI) were evaluated. Additionally, therapeutic strategy after FFR was recorded. Results Of 244 vessels, myocardial ischemia (FFR ≤0.80) was shown in 99 (40.6%). MTV was larger in the patients with FFR-verified ischemia than those without (53.3±19.2 vs. 41.5±21.6, P&lt;0.001); MLA, plaque burden (PB) and percentage of aggregated plaque volume (%APV) were also associated with ischemia. The area under the curves (AUCs) of MLA, PB, %APV, and MTV were 0.69, 0.67, 0.64, and 0.71, respectively. Addition of MTV to a model with coronary stenosis on visual, MLA, PB, and %APV improved C-index (from 0.72 to 0.79, P&lt;0.01), net reclassification improvement (NRI) (0.71, P&lt;0.01), and integrated discrimination improvement (IDI) (0.10, P&lt;0.01). Of 99 vessels with FFR ≤0.80, MVI was larger in the vessels with early revascularization after FFR than those without (38.8 vs. 29.1, P=0.01). Conclusions The measurement of myocardial mass improves the diagnostic performance of coronary CTA for the identification of coronary arteries with FFR-verified ischemia. Furthermore, it is associated with therapeutic strategy for the diseased vessels after FFR examination.

P2716Correlation between computed tomography derived ischemia index and conventional fractional flow reserve

Abstract Background Computed tomography (CT) derived ischemia index is a novel tool to determine the significance of coronary artery disease, however, its ability to identify myocardial ischemia has not been examined. Methods From Jan. 2013 to Dec. 2015, 14,000 patients underwent ECG-gated CT coronary angiography for suspected coronary artery disease. From Jan. 2013 to Jan. 2016, 483 patients (589 vessels) underwent conventional FFR to assess myocardial ischemia. Among those, FFR was assessed in 148 patients (167 vessels) within 30 days after CT coronary angiography. We further excluded 24 patients with prior stenting or bypass grafting, 3 patients with multiple MDCT or FFR, and 6 patients with insufficient datasets. Finally, we included 117 patients (127 vessels) to assess the correlation between CT derived ischemia index and conventional FFR. CT derived ischemia index was calculated as follows: left ventricular volume distally to the coronary artery lumen (cm3)/coronary artery lumen area (mm2). Left ventricular volume was automatically determined using Advantage Workstation and divided according to the nearest coronary artery tree. Center of coronary arteries were manually traced and contours of coronary artery lumen were automatically depicted. CT derived ischemia index was calculated at approximately every 0.625mm point of coronary artery. Moving median of consecutive 5 points (approximately 3.125mm) were used to remove outliers. Maximum value of CT derived ischemia index per coronary artery segment was calculated to determine the significance of coronary artery disease. Results Mean age was 71.3±10.5 years and 63.8% of patients were male. Coronary angiography was performed to assess conventional FFR at the median of 13 days (IQR 7 to 18 days) after CT. Majority of the target vessel was left anterior descending artery (71.7%), followed by right coronary artery (14.2%), left circumflex artery (13.4%) and left main coronary artery (0.8%). According to the quantitative coronary angiography, minimum lumen diameter was 1.47±0.32mm with percent diameter stenosis of 48.3±10.4%. Median FFR value was 0.83 (IQR 0.76 to 0.88) and positive test for myocardial ischemia (FFR &lt;0.80) was observed in 42 vessels (33.1%). Maximum CT derived ischemia index per segment ranged from 1.825 to 57.296 (median 8.333, IQR 4.911 to 14.484). There was a negative correlation between CT derived ischemia index and FFR (r=−0.319, 95% confidence interval −0.467 to −0.153, P&lt;0.001). Receiver operating characteristic analysis indicated CT derived ischemia index of 9.962 has 76.2% sensitivity and 70.6% specificity for the presence of FFR&lt;0.80 (AUC 0.73, 95% CI 0.64 to 0.82). Conclusions A novel tool of CT derived ischemia index has a significant negative correlation with conventional FFR in lesions with mild to moderate stenosis. Larger multicenter prospective studies are needed to fully determine the impact of CT derived ischemia index.

P973Intravascular lithotripsy for lesion preparation in calcified coronary lesions: a prospective, observational, two-center registry

Abstract Background Intravascular coronary lithotripsy (IVL) is a novel alternative treatment for heavily calcified lesions. This study sought to determine the strategy success and safety of IVL on calcified lesions in an all-comers cohort of patients. Methods Patients with moderate and severely calcified coronary lesions were screened in two centers in Spain and Germany starting April 2018. Until February 2019, 61 patients with 67 lesions were eligible for IVL. Patients were assigned to the following groups: A) Primary IVL therapy for patients with circumferential calcified de-novo coronary lesions (n=32), B) Secondary IVL therapy for patients with moderate or severe calcified coronary lesions in which conventional non-compliant balloon dilatation failed (n=18) and C) Tertiary IVL therapy in patients with in-stent stenosis due to stent underexpansion after previous stenting (n=17). Primary endpoint was strategy success and safety outcome. Strategy success was defined as successful stent delivery and expansion with attainment of &lt;20% in-stent residual stenosis of the target lesion. Safety outcome were procedural complication, defined as coronary dissection, slow or no-reflow phenomenon, new coronary thrombus formation during PCI, abrupt vessel closure and device failure (inability to place the balloon, malfunction, or burst) and in hospital MACE. Results 61 patients with 67 calcified lesions were treated with IVL. Mean diameter of calcified stenosis on quantitative coronary angiography was 72.02±13.8% at baseline and decreased to 17.7±15.84% (p-value: &lt;0.01) after IVL with an acute gain of 1.9±0.63 mm. Mean minimal lumen diameter was 1.0±0.5 mm at baseline and increased after IVL to 2.9±0.6 mm. The overall average of applied pulses was 63±22. The primary endpoint of strategy success was reached overall in 85.2% of patients. 4 type b dissections (3 in group A, 1 in group B) were observed without further sequelae. There were no in-hospital MACE. In one patient (1.6%) non-ischemia driven target lesion failure was observed in routine follow up coronary angiography and was in need for revascularization. According to the subgroups, strategy success in primary IVL treatment (group A) and secondary IVL treatment (group B) was reached in 81.3% and 83.3% of cases, respectively. In tertiary IVL therapy (group C), the primary study endpoint was reached in 64.7% of cases. Device delivery and IVL treatment of target lesion could be performed in all lesions without vessel complications. 7 IVL balloons ruptured during treatment without any sequelae. Rupture was observed in most cases after repositioning of the balloon within the calcified lesion. Conclusions IVL provides a valid strategy for lesion preparation in severely calcified coronary lesions, with high success rate, and low procedural complication and MACE rates. Longitudinal studies will confirm if these favourable initial results of IVL-supported PCI are followed by good long-term results.

P5632Different impact of lesion length on fractional flow reserve in intermediate coronary lesions between each coronary artery

Abstract Background Previous studies reported that lesion length was an important geometric parameter in addition to the degree of stenosis in the determinant of functional significance of coronary artery stenosis. Nevertheless, the optimal cutoff value of lesion length for predicting functional significance for each coronary artery has not yet been evaluated, though previous studies revealed that the cutoff value of minimum lumen diameter measured on coronary angiography (CAG) to predict fractional flow reserve (FFR) &lt;0.80 is different for each coronary artery Purpose This study evaluated whether the impact of lesion length on functional significance is similar between each coronary artery for lesions with intermediate stenosis. Methods Patients with suspected coronary artery disease who had at least one intermediate coronary lesion (luminal diameter stenosis of 70 to 80% by visual estimation on CAG) and underwent FFR measurement for the evaluation of myocardial ischemia were evaluated. Quantitative coronary angiography analysis including percent diameter stenosis and lesion length was performed. FFR was measured as the ratio of the mean distal coronary artery pressure to the mean aortic pressure during maximal hyperemia induced by intravenous infusion of adenosine triphosphate (150 μg /kg/min). The area under the receiver operating characteristics (ROC) curve was estimated for the best cutoff value as a predictor of FFR value of ≤0.80 for each coronary artery. Results A total of 221 de novo lesions that underwent FFR measurement were enrolled. The average FFR value was 0.81±0.07. Although lesion length was similar among the lesions with an FFR &gt;0.80 at different locations, the mean lesion length was significantly longer for lesions in the right coronary artery (RCA) with an FFR ≤0.80 than for those in the left anterior descending artery (LAD) and left circumflex artery (13.4±3.4 versus 8.6±3.1 versus 12.0±3.7 mm, p&lt;0.001). ROC analysis demonstrated that the optimal cutoff value of lesion length for predicting an FFR ≤0.80 was 10.0 mm in the LAD (0.56 area under the curve, 48% sensitivity, 76% specificity), whereas 13.1 mm in the RCA (0.84 area under the curve, 67% sensitivity, 93% specificity) (Figure). ROC analysis of LL for FFR≤0.80 Conclusions A longer lesion length is required to achieve FFR&lt;0.80 in the RCA than in the other arteries. This may suggest the low possibility of an FFR ≤0.80 when stenosis is focal and short in the RCA with stenosis of 70 to 80% by visual estimation on CAG.