Heavily calcified left main trunk bifurcation lesions remain challenging in percutaneous coronary intervention. An 82-year-old man presented with exertional dyspnea. Angiography revealed a heavily calcified distal left main trunk involving the left anterior descending artery and left circumflex artery. Intravascular ultrasound demonstrated circumferential calcification with a >270°arc. Triple-sequence rotational-orbital-rotational atherectomy (RA-OA-RA) was performed. The first RA created a bilobular lumen; OA enhanced wire bias toward the calcified arc; and the second RA generated an oval shape, enabling optimal stent expansion without burr upsizing. This represents the first intravascular ultrasound-validated RA-OA-RA sequence demonstrating stepwise morphological transformation.

Directional coronary atherectomy (DCA) requires precise spatial orientation. Although the tip detection method is established for intravascular ultrasound, its application in optical coherence tomography (OCT)-guided DCA remains unestablished. We present a case of functionally significant stenosis at the left anterior descending (LAD) artery ostium treated with OCT-guided DCA. We adapted the tip detection method using a second guidewire with a tip curve. Aligning the fluoroscopically directed guidewire with the 3 o'clock position on the OCT cross-section achieved precise three-dimensional spatial co-registration, enabling accurate plaque localization. This first report demonstrates that OCT-guided tip detection offers a safe and sophisticated debulking strategy for complex coronary lesions.

The aging population has led to an increase in nonagenarians undergoing percutaneous coronary intervention (PCI). Nonagenarian patients are at risk for geriatric complications, including delirium, which can worsen clinical outcomes. However, research on delirium and its clinical implications in nonagenarians with acute coronary syndrome (ACS) following PCI is limited.This retrospective observational cohort study analyzed data from 307 nonagenarians with ACS who underwent PCI. Delirium was diagnosed using the Diagnostic and Statistical Manual of Mental Disorders-5 criteria. Prevalence and prognostic impact of delirium during hospitalization were investigated.Delirium occurred in 85 patients (27.7%) during hospitalization. Patients with delirium had longer hospital stays and lower discharge rates to home or the same location as prior to hospitalization compared to patients without delirium. However, in-hospital mortality rates were comparable between the groups. Over a median follow-up of 480 days, no significant differences were found in all-cause mortality between the two groups.Delirium was common among nonagenarians with ACS following PCI. While delirium was associated with length of hospital stays and discharge destination, it was not linked to survival rates. Prevention, early detection, and effective management of delirium are important for optimizing care in super-aged patients following PCI.

BACKGROUND:Acute total or subtotal occlusion of the unprotected left main coronary artery (ULMCA) is a rare but severe condition with high short-term mortality. However, the long-term prognosis of patients who survive to discharge after emergent percutaneous coronary intervention (PCI) remains unclear. This study aimed to evaluate long-term clinical outcomes in this population. METHODS:This multicenter retrospective study analyzed 61 patients who survived to discharge after emergent PCI for acute total/subtotal ULMCA occlusion. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE), including all-cause mortality, target vessel revascularization, heart failure hospitalization, and stroke. Predictors of MACCE were assessed using Cox proportional hazards regression. RESULTS:The median age of the study cohort was 73 (63-77) years, and 72.1% were male. During a median follow-up of 5.4 (1.0-9.2) years from the date of discharge, MACCE occurred in 38 patients (62.3%). The MACCE rates at 5 and 10 years were 58.6% and 74.6%, respectively. The corresponding all-cause mortality rates were 33.5% and 47.4%. Cardiac death was observed in eight patients (13.1%), while 14 patients (23.0%) died from noncardiac causes. Among the clinical and procedural factors assessed, only intratracheal intubation at presentation was identified as an independent predictor of MACCE (adjusted hazard ratio: 2.15, 95% confidence interval: 1.10-4.24, p = 0.03). CONCLUSIONS:These findings suggest the importance of post-discharge management strategies for patients who underwent emergent PCI for acute total/subtotal ULMCA occlusion due to the persistent risk of cardiac or cerebrovascular events.

BACKGROUND:Injection and aspiration efficacy via microcatheter are important in complex percutaneous coronary intervention (PCI). AIMS:The aim of this study was to compare the injection and aspiration performance of different microcatheters under identical conditions. METHODS:In the injection bench test, injection volumes and times for each microcatheter were measured three times using an auto-injector. In the aspiration bench test, each microcatheter was connected to a two-way stopcock and an aspiration syringe. Times required to aspirate 5 mL (T1) and 10 mL (T2) of blood-mimicking fluid were measured. For the injection bench test, flow rates and resistance ratios were calculated, for the aspiration bench test, resistance ratios were calculated. The resistance ratio of the Finecross GT 130 cm was set as 1.0 (reference). RESULTS:The fastest flow rate (0.66 mL/s) and lowest resistance ratio (0.74) in the injection test were observed with the Zizai 130 cm. Conversely, dual-lumen catheters exhibited the slowest flow rates (Sasuke and Crusade Type R: 0.14 mL/s, 0.19 mL/s) and highest resistance ratios (Sasuke and Crusade Type R: 3.43, 2.53). In the aspiration bench test, the Zizai 130 cm exhibited the shortest aspiration times (T1, 73.0 s, T2, 140.7 s) and lowest resistance ratio (average R1, R2: 0.74), whereas the Corsair Pro 135 cm exhibited the longest aspiration times (T1, 174 s, T2, 330.3 s) and highest resistance ratios (R1, 1.78, R2, 1.72; average, 1.75). CONCLUSION:To our knowledge, this is the first comparison of injection efficacy and aspiration resistance among various microcatheters for PCI, providing practical guidance for microcatheter selection in complex PCI.

The aging population has led to an increase in nonagenarians undergoing percutaneous coronary intervention (PCI). Nonagenarian patients are at risk for geriatric complications, including delirium, which can worsen clinical outcomes. However, research on delirium and its clinical implications in nonagenarians with acute coronary syndrome (ACS) following PCI is limited. This retrospective observational cohort study analyzed data from 307 nonagenarians with ACS who underwent PCI. Delirium was diagnosed using the Diagnostic and Statistical Manual of Mental Disorders-5 criteria. Prevalence and prognostic impact of delirium during hospitalization were investigated. Delirium occurred in 85 patients (27.7%) during hospitalization. Patients with delirium had longer hospital stays and lower discharge rates to home or the same location as prior to hospitalization compared to patients without delirium. However, in-hospital mortality rates were comparable between the groups. Over a median follow-up of 480 days, no significant differences were found in all-cause mortality between the two groups. Delirium was common among nonagenarians with ACS following PCI. While delirium was associated with length of hospital stays and discharge destination, it was not linked to survival rates. Prevention, early detection, and effective management of delirium are important for optimizing care in super-aged patients following PCI.

The proportion of young females among the patients who undergo percutaneous coronary intervention (PCI) is relatively small, and information on their clinical characteristics is limited. This study investigated the clinical characteristics and prognostic factors for future cardiac events in young females who underwent PCI. This multicenter observational study included 187 consecutive female patients aged < 60 years who underwent PCI in seven hospitals. The primary composite endpoint was the incidence of cardiac death, nonfatal myocardial infarction, and target vessel revascularization. The mean patient age was 52.1 ± 6.1 years and 89 (47.6

BACKGROUND:In an aging society, percutaneous coronary intervention (PCI) for super-elderly patients is commonly performed in clinical practice. However, data are scarce regarding the clinical features and outcomes of this population. METHODS:This multicenter observational study enrolled patients aged over 90 years who underwent PCI across 10 hospitals between 2011 and 2020. The study included patients presenting with acute coronary syndrome (ACS) and chronic coronary syndrome (CCS). The occurrence of all-cause and cardiac deaths during hospitalization and after discharge was investigated. RESULTS:In total, 402 patients (91.9 ± 2.0 years, 48.3 % male) participated in the study, of whom 77.9 % presented with ACS. The rate of in-hospital death was significantly higher in patients with ACS compared to patients with CCS (15.3 % vs. 2.2 %, p < 0.001). The estimated cumulative incidence rates of all-cause death were 24.3 %, 39.5 %, and 60.4 % at 1, 3, and 5 years, respectively. No significant difference was observed in the occurrence of all-cause death between patients with ACS and CCS. Regarding causes of death after discharge, non-cardiac deaths accounted for just over half of the cases. CONCLUSION:This study highlights the clinical features and long-term clinical course of patients aged over 90 years who underwent PCI in a real-world setting. Patients presenting with ACS exhibited a higher rate of in-hospital mortality compared to those with CCS. Following discharge, both ACS and CCS patients experienced comparable and substantial increases in the incidence rates of both cardiac and non-cardiac mortality over time, and a more holistic management approach is warranted.

OBJECTIVE To clarify the correction effect of the latest motion artefact correction technique by visual evaluation. MATERIALS & METHODS The cases obtained by coronary CT angiography were divided into three groups: low (below 60 bpm), medium (60–69 bpm), and high (over 70 bpm). The CPR images of the three coronary arteries were created in the optimal cardiac phase with and without motion correction for all cases. The image quality of these CPR images was visually evaluated by two cardiologists who had experience reading coronary CT images and scored on a 5-point scale (1. Bad, 2. Poor, 3. Fair, 4. Good, 5. Excellent). RESULTS In the medium group, uncorrected mean scores with single-sector reconstruction (SSR) were 3.8±0.8 for LCA (LAD, LCx), and 3.6±1.0 for RCA. The uncorrected scores with multi-sector reconstruction (MSR) were 3.9±0.7 for LCA, and 3.9±1.1 for RCA. With correction, LCA was 4.0±0.7, and RCA was 3.7±0.5. In the high group, uncorrected mean scores with SSR were 3.1±0.8 for LCA, and 2.5±0.8 for RCA. The uncorrected scores with MSR were 3.9±0.9 for LCA, and 3.3±1.1 for RCA. On the other hand, with correction, LCA was 3.9±0.8, and RCA was 3.7±1.1. CONCLUSION From these results, even in the case of a high heart rate, this correction technique can provide the temporal resolution equivalent to MSR and the image quality equivalent to SSR. To clarify the correction effect of the latest motion artefact correction technique by visual evaluation. The cases obtained by coronary CT angiography were divided into three groups: low (below 60 bpm), medium (60–69 bpm), and high (over 70 bpm). The CPR images of the three coronary arteries were created in the optimal cardiac phase with and without motion correction for all cases. The image quality of these CPR images was visually evaluated by two cardiologists who had experience reading coronary CT images and scored on a 5-point scale (1. Bad, 2. Poor, 3. Fair, 4. Good, 5. Excellent). In the medium group, uncorrected mean scores with single-sector reconstruction (SSR) were 3.8±0.8 for LCA (LAD, LCx), and 3.6±1.0 for RCA. The uncorrected scores with multi-sector reconstruction (MSR) were 3.9±0.7 for LCA, and 3.9±1.1 for RCA. With correction, LCA was 4.0±0.7, and RCA was 3.7±0.5. In the high group, uncorrected mean scores with SSR were 3.1±0.8 for LCA, and 2.5±0.8 for RCA. The uncorrected scores with MSR were 3.9±0.9 for LCA, and 3.3±1.1 for RCA. On the other hand, with correction, LCA was 3.9±0.8, and RCA was 3.7±1.1. From these results, even in the case of a high heart rate, this correction technique can provide the temporal resolution equivalent to MSR and the image quality equivalent to SSR.

Background: Patients with a right dominant coronary artery anatomy account for a significant proportion of acute myocardial infarction cases, and this condition is associated with a better prognosis. However, there are limited data on the impact of coronary dominance on patients with acute total/subtotal occlusion of unprotected left main coronary artery (ULMCA).Methods: This study aimed to assess the impact of right coronary artery (RCA) dominance on long-term mortality in patients with acute total/subtotal occlusion of the ULMCA. From a multicenter registry, 132 cases of consecu-tive patients who had undergone emergent percutaneous coronary intervention (PCI) due to acute total/subtotal occlusion of the ULMCA were reviewed.Results: Patients were classified into two groups according to the size of their RCA (dominant RCA group, n = 29; non-dominant RCA group, n = 103). Long-term outcomes were examined according to the presence of dominant RCA. Cardiopulmonary arrest (CPA) occurred in 52.3 % of patients before revascularization. All-cause death was significantly lower in the dominant RCA group than in the non-dominant RCA group. In the Cox regression model, dominant RCA was an independent predictor of all-cause death, as well as total occlusion of ULMCA, collateral from RCA, chronic kidney disease, and CPA. Patients were further analyzed according to the degree of stenosis of the ULMCA; patients with non-dominant RCA and total occlusive ULMCA had the worst outcome compared with the other groups.Conclusions: A dominant RCA might improve long-term mortality in patients with acute total/subtotal occlusion of the ULMCA who were treated with PCI.& COPY; 2023 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Mitral isthmus (MI) ablation for mitral flutter is technically difficult, and incomplete block line is not uncommon. The objective of this study is to investigate the effect of the ridge line of left pulmonary vein isolation (LPVI) from left atrial appendage (LAA) on completion rate of mitral isthmus (MI) block line and recurrence rate of atrial tachycardia (AT) or atrial flutter (AFL) after the first MI ablation. We identified 611 patients who underwent first MI ablation for mitral flutter during the study period. Finally, 559 patients were enrolled and divided into two groups according to the method of ridge line ablation of LPVI (LAA group, n = 467, conventional group, n = 92). Outcome measures were the completion of MI block line by first MI ablation, the recurrence of AT/AFL, and repeat MI ablation after the first MI ablation. The first MI block line completion rate was significantly higher in the LAA group than the conventional group (95% vs. 85%, p < 0.001). The recurrence rate of AT/AFL after 3 months from first MI ablation was significantly lower in the LAA group. The requirement of additional MI ablation tended to be lower in the LAA group. Our novel approach of ablating LPV-LAA ridge from the LAA side during PVI can increase the success rate of MI block line completion, and reduce the recurrence rate of AT/AFL and the need for additional MI block line ablation.

Despite the excellent long-term results of internal mammary artery (IMA)-left anterior descending (LAD) bypass, percutaneous revascularization of IMA is sometimes required for IMA-LAD bypass failure. However, its clinical outcomes have not been fully elucidated. The aim of this study was to investigate the long-term clinical outcomes, including target lesion revascularization (TLR) following contemporary percutaneous revascularization of failed IMA bypass graft. We examined data of 59 patients who had undergone percutaneous revascularization of IMA due to IMA-LAD bypass failure at nine hospitals. Patients with IMA graft used for Y-composite graft or sequential bypass graft were excluded. The incidence of TLR was primarily examined, whereas other clinical outcomes including cardiac death, myocardial infarction, and target vessel revascularization were also evaluated. Mean age of the enrolled patients was 67.4 +/- 11.3 years, and 74.6% were men. Forty patients (67.8%) had anastomotic lesions, and 17 (28.8%) underwent revascularization within three months after bypass surgery. Procedural success was achieved in 55 (93.2%) patients. Stent implantation was performed in 13 patients (22.0%). During a median follow-up of 1401 days (interquartile range, 282-2521 days), TLR was required in six patients (8.5% at 1, 3, and 5 years). Patients who underwent percutaneous revascularization within 3 months after surgery tended to have a higher incidence of TLR. Clinical outcomes of IMA revascularization for IMA-LAD bypass failure were acceptable.

Background The efficacy of pulmonary vein isolation (PVI) alone is not guaranteed for persistent atrial fibrillation (PeAF), and it is unclear which type of ablation approach should be applied in addition to PVI. This study aimed to compare outcomes and prognosis between empirical linear ablation and low-voltage area (LVA) ablation after PVI for PeAF. Methods We enrolled 128 patients with PeAF who were assigned to the linear ablation group (n = 64) and the LVA ablation group (n = 64) using a propensity score-matched model. After PVI and cardioversion, the patients underwent either empirical linear ablation or LVA ablation during sinus rhythm. All patients in the linear ablation group underwent both roof line and mitral valve isthmus (MVI) ablations. An electrical-guided ablation targeting LVA (< 0.5 mV) was performed in the LVA group. When there was no LVA in the LVA group, only PVI was applied. We compared the procedural outcomes and recurrence after ablation between the two groups. Results The baseline characteristics were well-balanced between the two groups. Fifty patients had LVA (22 and 28 patients in the linear and LVA groups). The roof and MVI lines were completed in 100% and 96.9% of the patients. During the mean follow-up of 279.5 ± 161.3 days, the LVA group had significantly lower recurrence than the linear group (15 patients [23%] vs. 29 patients [45%], p = 0.014). Thirty-five patients were prescribed antiarrhythmic drugs during the follow-up period (linear group, n = 17; LVA group, n = 18); amiodarone and bepridil were administered to most of the patients (15 and 17 patients, respectively). The difference in the prognosis was relevant among the patients with LVA, while this trend was not observed in those without LVA. The LVA ablation group demonstrated significantly lower radiofrequency energy and shorter procedural time compared to the linear ablation group. The recurrence of atrial flutter was more likely to occur in the linear group than in the LVA group (14 [22%] vs. 6 [9.4%], p = 0.052). Conclusion The electrophysiological-guided LVA ablation is more effective than empirical linear ablation in PeAF patients with LVA. Unnecessary empirical linear ablation might have a risk of iatrogenic gap and atrial flutter recurrence.

Introduction: Acute coronary syndrome involving the unprotected left main coronary artery (LMCA) is a fatal event. However, data regarding clinical features and outcomes in patients presenting with acute total/subtotal occlusion of the unprotected LMCA remain limited, and the impact of vital status in the emergency room (ER) remains unknown in such subjects. Methods: From a multi-center registry of 11977 emergent percutaneous coronary interventions (PCIs), 134 patients due to acute total/subtotal occlusion of the unprotected LMCA were reviewed. ER status classification was defined according to the presence of cardiogenic shock and cardiopulmonary arrest (CPA) in the ER (class 1=no cardiogenic shock; class 2= cardiogenic shock but not CPA; and class 3=CPA). We evaluated in-hospital mortality and cerebral performance category (CPC) as the endpoints. Results: One-half (67/134) of the enrolled patients presented with total occlusion of the unprotected LMCA. Regarding ER status classification, class 1, 2, and 3 were observed in 30.6%, 45.5%, and 23.9% of the patients, respectively. In-hospital mortality occurred in 73 (54.5%) patients, then of the remaining patients, 52 (85.3%) could be discharged with favorable neurological outcomes (CPC 1 or 2). ER status classification (odds ratio 4.79 [95% confidence interval: 2.39-9.62]; p<0.001) and total occlusion of the unprotected LMCA (odds ratio 5.79 [95% confidence interval 2.27-14.73]; p<0.001) were strong predictors of in-hospital mortality. Conclusions: Acute total/subtotal occlusion involving the unprotected LMCA appeared to be associated with high in-hospital mortality. ER status classification and initial flow in the unprotected LMCA were important predictive factors of in-hospital mortality.

The outbreak of coronavirus disease 19 (COVID-19) has had a great impact on medical care. During the COVID-19 pandemic, the rate of hospital admissions has been lower and the rate of in-hospital mortality has been higher in patients with acute coronary syndrome (ACS) in Western countries. However, in Japan, it is unknown whether the COVID-19 pandemic has affected the incidence of ACS. In the study, eleven hospitals in the Tokai region participated. Among enrolled hospital, we compared the incidence of ACS during the COVID-19 pandemic (April and May, 2020) with that in equivalent months in the preceding year as the control. During the study period; April and May 2020, 248 patients with ACS were admitted. Compared to April and May 2019, a decline of 8.1% [95% confidence interval (CI) 5.2-12.1; P = 0.33] in admissions for ACS was observed between April and May 2020. There was no significant difference in the strategy for revascularization and in-hospital deaths between 2019 and 2020. In conclusion, the rate of admission for ACS slightly decreased during the COVID-19 pandemic, compared to the same months in the preceding year. Moreover, degeneration of therapeutic procedures for ACS did not occur.

BACKGROUND Spontaneous coronary artery dissection (SCAD) has recently been recognized as a cause of acute coronary syndrome (ACS), especially in young women. However, the characteristics, optimal treatment, and prognosis of patients who experience SCAD have not been fully described. METHODS Data were retrospectively collected from a multicenter registry. Among 187 young women less than 60 years of age who underwent percutaneous coronary intervention, 19 (10.2%) with SCAD were identified through coronary angiography. Clinical characteristics and outcomes were investigated. RESULTS Those with SCAD less frequently exhibited coronary risk factors, such as diabetes, dyslipidemia, and smoking, than those without SCAD. Intense emotional and/or physical stress was more frequently observed as a prominent precipitating factor in cases of SCAD. All 19 SCAD patients presented with ACS, 7 of whom were treated using stents, and the other 12 treated without stents. During a median follow-up of 960 days (interquartile range, 686-1504 days), two recurrent coronary artery dissections occurred within 7 days, both of which occurred in a vessel other than that in which primary dissection occurred. There were no deaths or recurrent dissection after 1 week. CONCLUSION SCAD was not uncommon among young Japanese women requiring percutaneous coronary intervention. Patients with SCAD exhibited fewer coronary risk factors and more precipitating factors than those without SCAD, and long-term clinical outcomes after an early period appeared to be favorable.

Methods : We evaluated consecutive 530 patients who were underwent catheter ablation for Af between May 2017 and October 2018 in our institute. And we exclude 108 patients who were prescribed Dabigatran or Warfarin on an outpatient basis and 75 patients who could not replace prescribed Edoxaban, Rivaroxaban or Apixaban with Dabigatran because of age or creatinine clearance (CCR). We enrolled 347 patients in this study. We divided them into 2 groups (Dabigatran bridging group and nonbridging group). Dabigatran bridging group, we replaced Edoxaban, Rivaroxaban or Apixaban with Dabigatran for two days from the operation day (N=236). And non-bridging group, we continue Edoxaban, Rivaroxaban or Apixaban (N=111). The end point was hemorrhagic complication and thromboembolic event including cerebral infarction.

Introduction: There is general interest in finding clinical markers for left ventricular diastolic dysfunction (LVDD), a major cause of cardiorenal syndrome leading to heart failure in chronic kidney disease (CKD) patients. The aim was to assess the utility of computed tomography (CT)-based abdominal aortic calcification (AAC) for the prediction of LVDD and prognosis of asymptomatic pre-dialysis CKD patients. Materials and methods: We prospectively evaluated 218 pre-dialysis CKD patients [median estimated glomerular filtration rate (eGFR); 40.9 mL/min/1.73m²]. Non-contrast CT scan and echocardiography were performed to determine the aortic calcification index (ACI) as a semi-quantitative measure of AAC. Results: The median ACI was 11.4. AAC and LVDD were diagnosed in 193 patients (89%) and 75 patients (34%), respectively. Using receiver operating characteristic curve analysis for the estimation of LVDD, ACI of 20 showed optimal sensitivity (52.0%) and specificity (62.8 %) (AUC = 0.664, p < .001). High ACI group included more patients with LVDD-related factors, such as old age, hypertension, diabetes, and more severe CKD. LVDD was significantly more common in patients with high ACI group [39 (50%) and 36 (26%), respectively, p<0.001]. Multivariate analysis showed that ACI correlated significantly with E/A (β=-0.993, p=0.003), E/e' (β=0.077, p<0.001), and cardio-ankle vascular index (β=0.209, p=0.001). Correspondingly, E/e' correlated with logBNP and log(ACI+1), and increased proportionately and significantly with the quartiles of ACI values. Cox proportional hazard models showed that ACI was an independent predictor of CV outcome (hazard ratio 1.03, 95% confidence interval 1.00-1.06, p=0.029). Conclusion: The results would suggest the usefulness of AAC assessment by CT to predict latent LVDD and future CV risk in asymptomatic pre-dialysis CKD patients.

BACKGROUND:Myokines are hormones secreted by skeletal muscles during physical activity. Low myokine levels may contribute to metabolic dysfunction and cardiovascular disorders. Irisin, a newly identified myokine, has been the focus of recent research. The aim of the present study was to analyze the association between circulating irisin levels and tissue characteristics of nonculprit left main coronary artery (LMCA) plaques with the use of integrated backscatter (IB) intravascular ultrasound (IVUS).METHODS:This observational study enrolled 55 Japanese patients following successful percutaneous coronary intervention for lesions in the left anterior descending arteries or left circumflex arteries. Circulating myokine levels, including myostatin, brain-derived neurotrophic factor, and irisin, were measured by an enzyme-linked immunosorbent assay. Tissue characteristics of LMCA plaque were evaluated by IB-IVUS.RESULTS:Circulating irisin levels were negatively associated with percent lipid volume (%LV) [r = -0.31 (95% CI, -2.52 to -0.21), P = 0.02] and positively associated with percent fibrous volume (%FV) [r = 0.32 (95% CI, 0.22-2.20), P = 0.02]. The optimal cutoff value of circulating irisin for the prediction of lipid-rich LMCA plaques was 6.02 μg/mL [area under the curve = 0.713, P < 0.01 (95% CI, 0.58-0.85)]. Multivariate linear regression analysis identified circulating irisin levels as independent predictors for %LV and %FV of the LMCA [β = -0.29 (95% CI, -2.53 to -0.07), P = 0.04 and β = 0.30 (95% CI, 0.10-2.23), P = 0.03, respectively].CONCLUSIONS:Circulating irisin levels are significantly associated with tissue characteristics of nonculprit LMCA plaques.