Vasa vasorum enhancement on optical coherence tomography in Kawasaki disease.

BACKGROUND: Patients with Kawasaki disease (KD) prone to develop coronary artery aneurysm (CAA) with unknown etiology. We aimed to disclose the relationship between vasa vasorum (VV) and intimal thickening using optical coherence tomography (OCT) in KD. METHODS: Forty-three coronary artery branches of 21 patients with KD were examined by OCT. The coronary arteries were classified into three groups: the CAA group (n = 9) in which CAAs remained since the acute phase, the regressed group (n = 16) in which CAAs were regressed, and the no CAA group (n = 18). The number and distribution of VV, and intimal thickening in coronary arteries were evaluated on OCT. RESULTS: Intimal thickening was significantly more severe in the CAA and regressed groups than in the no CAA group (median: 481, 474, and 218 µm, p = 0.001 and p < 0.001, respectively). The number of VV in the regressed group was significantly higher than that in the CAA and no CAA groups. The numbers of adventitial VV and internal VV were positively correlated with the intimal thickness (R = 0.64, p < 0.001; R = 0.62, p < 0.001, respectively). In the no CAA group, no internal VV were observed. CONCLUSIONS: VV enhances according to intimal thickening, suggesting that VV may have some link to the healing process, such as CAA regression and intimal thickening. IMPACT: Kawasaki disease (KD) is a vasculitis syndrome developing coronary artery aneurysm, however its etiology still remains unclear. Coronary artery imaging using optical coherence tomography (OCT) can reveal coronary arterial wall pathology, however OCT studies are limited in patients with KD. Using OCT, we disclosed the closed relationship between vasa vasorum enhancement and regressed coronary arterial lesions. Vasa vasorum enhancement is involved in the pathomechanism of the convalescent phase of KD.

Pathological Alterations of Coronary Arteries Late After Kawasaki Disease: An Optical Coherence Tomography Study.

Background: The long-term impact of Kawasaki disease on coronary arteries in vivo is unclear. Objectives: The purpose of this study was to investigate coronary arteries in the late convalescent phase, we followed patients with Kawasaki disease who developed coronary artery aneurysms (CAAs). Methods: We followed 24 patients and used optical coherence tomography at a median of 16.6 years after the onset of Kawasaki disease. Results: Of 72 coronary arteries, optical coherence tomography was performed on 61 arteries: 17 with a persistent CAA, 29 with a regressed CAA, and 15 without a CAA. Between-group comparison was performed by chi-square or Fisher's exact test, and intimal thickening (17 vs 29 vs 15, all 100%, P = NA) and medial disruption (17 [100%] vs 29 [100%] vs 14 [93%], P = 0.25) were commonly observed in the investigated arteries. Advanced features of atherosclerosis were more frequently seen in arteries with persistent CAAs than in those with regressed CAAs and in those without CAAs: calcification (12 [71%] vs 5 [17%] vs 1 [7%], P < 0.001), microvessels (12 [71%] vs 10 [35%] vs 4 [27%], P = 0.020), cholesterol crystals (6 [35%] vs 2 [7%] vs 0 [0%], P = 0.009), macrophage accumulation (11 [65%] vs 4 [14%] vs 4 [27%], P = 0.002), and layered plaque (8 [47%] vs 11 [38%] vs 0 [0%], P = 0.004). Conclusions: Long after onset of Kawasaki disease, all arteries showed pathological changes. Arteries with persistent CAAs had more advanced features of atherosclerosis than those with regressed CAAs and those without CAAs.

Low Energy Intake Diagnosed Using the Harris-Benedict Equation Is Associated with Poor Prognosis in Elderly Heart Failure Patients.

INTRODUCTION: Insufficient nutrient intake is a strong independent predictor of mortality in elderly patients with heart failure. However, it is unclear to what extent energy intake affects their prognosis. This study investigated the association between patient outcomes and actual measured energy intake in elderly patients (≥65 years) with heart failure. METHODS: This study enrolled 139 elderly patients who were hospitalized with worsening heart failure at Shingu Municipal Medical Center, Shingu, Japan, between May 2017 and April 2018. Energy intake was evaluated for three days (from three days prior to the day of discharge until the day of discharge). Based on basal energy expenditure calculated using the Harris-Benedict equation, the patients were classified into a low-energy group (n = 38) and a high-energy group (n = 101). We assessed the prognosis in terms of both all-cause mortality and readmission due to worsening heart failure as a primary outcome. RESULTS: Compared to the patients in the high-energy group, the patients in the low-energy group were predominantly female, less frequently had smoking habits and ischemic heart diseases, and had a higher left ventricular ejection fraction. The low-energy group had higher mortality than the high-energy group (p = 0.028), although the two groups showed equivalent event rates of the primary outcome (p = 0.569). CONCLUSION: Calculations based on the Harris-Benedict equation revealed no significant difference in the primary outcome between the two groups, with a secondary outcome that showed worse mortality in the low-energy group. Given this result, energy requirement-based assessments using the Harris-Benedict equation might help in the management of elderly heart failure patients in terms of improved life outcomes.

Characteristics of Discharged Elderly Patients with Acute Heart Failure Followed by Board-Certified-Cardiologists in a Rural Area of Japan.

The worldwide incidence rates of heart failure (HF) are approaching pandemic status due to aging societies. Board-certified cardiologists (BCCs) of the Japanese Circulation Society (JCS) are cardiologists who have completed the respective fellowship program and passed the examination. However, in rural areas, patients have limited access to medical care for social or geographical reasons. The clinical features of the specialist's follow-up for HF patients in rural areas are unclear.This study consists of 205 consecutive discharged elderly patients who were admitted to our hospital due to acute HF (AHF). All patients were recommended for follow-up with BCCs-JCS by the multidisciplinary HF team at the discharge-care planning meeting. The aim of this study was to investigate the clinical features and impact of BCC follow-up for discharged elderly patients with AHF in rural areas.A total of 156 patients chose follow-up with BCCs-JCS (BCC group), and 49 patients chose follow-up with non-BCCs-JCS (non-BCC group). Patients in the BCC group were younger (83 [76-86] versus 89 [75-93] years old, P < 0.001) and had more frequent use of ß-blockers (67% versus 39%, P < 0.001). The degree of frailty assessed by the clinical frailty scale was more severe in the non-BCC group than in the BCC group (4 [3-5] versus 6 [4-7], P < 0.001). The non-BCC group lived in nursing homes more frequently than the BCC group (16% versus 5%, P = 0.011).The HF patients followed by BCCS-JCS in rural areas were younger and had less frailty.

Clinical outcomes of acute myocardial infarction arising from non-lipid-rich plaque determined by NIRS-IVUS.

Acute myocardial infarction (AMI) can rarely arise from non-lipid-rich coronary plaques. This study sought to compare the clinical outcomes after percutaneous coronary intervention (PCI) between AMI showing maximum lipid-core burden index in 4 mm (maxLCBI4mm) < 400 and ≥ 400 in the infarct-related lesions assessed by near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). We investigated 426 AMI patients who underwent NIRS-IVUS in the infarct-related lesions before PCI. Major adverse cardiovascular events (MACE) were defined as the composite of cardiac death, non-fatal MI, clinically driven target lesion revascularization (TLR), clinically driven non-TLR, and congestive heart failure requiring hospitalization. 107 (25%) patients had infarct-related lesions of maxLCBI4mm < 400, and 319 (75%) patients had those of maxLCBI4mm ≥ 400. The maxLCBI4mm < 400 group had a younger median age at onset (68 years [IQR: 57-78 years] vs. 73 years [IQR: 64-80 years], P = 0.007), less frequent multivessel disease (39% vs. 51%, P = 0.029), less frequent TIMI flow grade 0 or 1 before PCI (62% vs. 75%, P = 0.007), and less frequent no-reflow immediately after PCI (5% vs. 11%, P = 0.039). During a median follow-up period of 31 months [IQR: 19-48 months], the frequency of MACE was significantly lower in the maxLCBI4mm < 400 group compared with the maxLCBI4mm ≥ 400 group (4.7% vs. 17.2%, P = 0.001). MaxLCBI4mm < 400 was an independent predictor of MACE-free survival at multivariable analysis (hazard ratio: 0.36 [confidence interval: 0.13-0.98], P = 0.046). MaxLCBI4mm < 400 measured by NIRS in the infract-related lesions before PCI was associated with better long-term clinical outcomes in AMI patients.

Reversible and multiphasic parenchymal changes in MRI after coil embolization for a ruptured cerebral aneurysm.

Background: Reversible and multiphasic parenchymal changes in magnetic resonance imaging (MRI) are exceedingly rare. The authors experienced a case of reversible and multiphasic parenchymal changes in MRI after coil embolization for a ruptured cerebral aneurysm. Case Description: A 48-year-old woman had a sudden onset of severe headaches and was referred to us for coil embolization. She was alert-oriented and had no neurologic deficits. Her medical history was atopic dermatitis and metal allergy. A head computed tomography (CT) scan demonstrated subarachnoid hemorrhage, and three-dimensional-CT angiography revealed a left internal carotid artery-posterior communicating artery aneurysm. Coil embolization was performed on the next day and seven coils made by three different manufacturers were used for the embolization. Despite no neurologic deficits after the surgery and no abnormal findings in MRI 7 days after the coil embolization, an MRI 2 weeks after embolization demonstrated delayed multiple white matter high intense lesions on T2-weighted image and fluid-attenuated inversion recovery in the left hemisphere. Repeat MRI scans showed multiple high intense lesions at various locations and at different timings. The blood test revealed the elevation of the proportion of EOS up to 9.7%, strongly indicating some allergic response. The MRI scan obtained 3 months after the onset confirmed the complete disappearance of the lesions. Conclusion: Given her history of metal allergy, and the reversible and multiphasic lesions in the non-vascular territories of the treated aneurysm, metal allergic encephalitis was most likely despite no clear evidence.

Early Healing of Spontaneous Coronary Artery Dissection Confirmed by Optical Coherence Tomography.

Our image series show the use of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) in the diag- nosis and treatment of a 52-year-old male who was admitted to our hospital because of inferior ST-segment-elevation myocardial infarction. An emergent coronary angiogram showed the total occlusion at the proximal site of the right coronary artery (RCA). IVUS revealed false lumen and intramural hematoma, as well as intimal tear at the proximal site of RCA, diagnosed as a spontaneous coronary artery dissection (SCAD). A drug-eluting stent was implanted over the intimal tear at the proximal site of the RCA. Twenty-eight days later, OCT demonstrated completely healed SCAD with TIMI 3 flow. OCT can visualize the 3-layered construction of the vessel wall and accurately diagnose SCAD. This image provides a presentation of early healing of acute SCAD confirmed by OCT, and might help in the management of acute SCAD.

Impact of Upper Arm Prolonged Occlusion on Radial Artery Diameter Before Coronary Angiography in Patients With Coronary Artery Disease.

BACKGROUND: The transradial approach (TRA) for percutaneous coronary angiography and intervention has been increasingly gaining popularity in clinical practice. However, there are cases in which it is difficult to insert a sheath or catheter due to spasm, pulsation loss, and occlusion. It has been reported that flow-mediated dilatation (FMD) contributed to the reduction of complications due to the TRA and the improvement of the number of puncture attempts. We hypothesized that FMD might increase the radial artery diameter and plasma nitric oxide (NO). METHODS AND RESULTS: A prospective, single-blind, randomized, parallel-group, single-center study to investigate the effect of FMD on radial artery diameter. Fifty-four patients were enrolled and randomly assigned into the pressure group or non-pressure group. Radial artery diameter pre and post procedure and plasma NO after sheath canulation were analyzed in both groups. We measured the biological NO as its stable metabolic products, nitrite and nitrate, and express the results as total nitrogen oxides (NOx). The diameter of pre-procedural radial artery was similar between the 2 groups. However, in the pressure group, the increase of radial artery diameter between post- and pre-procedure was significantly greater than those in the non-pressure group (pressure group; 0.18 [0.07-0.29] mm vs. non-pressure group; -0.33 [-0.04 to -0.22] mm, p = 0.001). No significant differences were observed in terms of plasma NOx between the 2 groups. CONCLUSIONS: It was possible to prove the increase in the radial artery diameter by performing FMD in the clinical practice, and to support the feasibility of FMD.

Long-term risk stratification for hospitalized patients with acute heart failure at a single rural cardiovascular centre.

AIMS: Early risk stratification of patients with acute heart failure (AHF) is critical for appropriate triage and outcome improvement. The serum sodium, blood urea nitrogen, age, serum albumin, systolic blood pressure, and natriuretic peptide level (SOB-ASAP) score can predict in-hospital mortality of AHF. However, the relationship between the SOB-ASAP score and long-term prognosis is unknown. This study investigated the determinants of the long-term prognosis of AHF by evaluating the SOB-ASAP score. METHODS: This retrospective cohort study included all patients with acute decompensated heart failure who were admitted to our hospital between April 2017 and March 2018. And those who discharged were analysed retrospectively. The follow-up period was 3 years. Primary end point was all-cause death. RESULTS: Total of 140 patients were analysed. The median SOB-ASAP score of entire cohort on admission was 3 points (interquartile range; 1-5). The Kaplan-Meier curve demonstrated that patients in the higher SOB-ASAP group (score ≥3) had a higher incidence of all-cause death (log-rank test; P < 0.001) than those in the lower SOB-ASAP (group score <3). CONCLUSIONS: At admission, the SOB-ASAP score may be useful for predicting the long-term prognosis of hospitalized patients with AHF.

A phase I/II study of triple-mutated oncolytic herpes virus G47∆ in patients with progressive glioblastoma.

Here, we report the results of a phase I/II, single-arm study (UMIN-CTR Clinical Trial Registry UMIN000002661) assessing the safety (primary endpoint) of G47∆, a triple-mutated oncolytic herpes simplex virus type 1, in Japanese adults with recurrent/progressive glioblastoma despite radiation and temozolomide therapies. G47Δ was administered intratumorally at 3 × 108 pfu (low dose) or 1 × 109 pfu (set dose), twice to identical coordinates within 5-14 days. Thirteen patients completed treatment (low dose, n = 3; set dose, n = 10). Adverse events occurred in 12/13 patients. The most common G47Δ-related adverse events were fever, headache and vomiting. Secondary endpoint was the efficacy. Median overall survival was 7.3 (95%CI 6.2-15.2) months and the 1-year survival rate was 38.5%, both from the last G47∆ administration. Median progression-free survival was 8 (95%CI 7-34) days from the last G47∆ administration, mainly due to immediate enlargement of the contrast-enhanced area of the target lesion on MRI. Three patients survived >46 months. One complete response (low dose) and one partial response (set dose) were seen at 2 years. Based on biopsies, post-administration MRI features (injection site contrast-enhancement clearing and entire tumor enlargement) likely reflected tumor cell destruction via viral replication and lymphocyte infiltration towards tumor cells, the latter suggesting the mechanism for "immunoprogression" characteristic to this therapy. This study shows that G47Δ is safe for treating recurrent/progressive glioblastoma and warrants further clinical development.

Intratumoral oncolytic herpes virus G47∆ for residual or recurrent glioblastoma: a phase 2 trial.

This investigator-initiated, phase 2, single-arm trial primarily assessed the efficacy of G47∆, a triple-mutated, third-generation oncolytic herpes simplex virus type 1, in 19 adult patients with residual or recurrent, supratentorial glioblastoma after radiation therapy and temozolomide (UMIN-CTR Clinical Trial Registry UMIN000015995). G47Δ was administered intratumorally and repeatedly for up to six doses. The primary endpoint of 1-yr survival rate after G47∆ initiation was 84.2% (95% confidence interval, 60.4-96.6; 16 of 19). The prespecified endpoint was met and the trial was terminated early. Regarding secondary endpoints, the median overall survival was 20.2 (16.8-23.6) months after G47∆ initiation and 28.8 (20.1-37.5) months from the initial surgery. The most common G47∆-related adverse event was fever (17 of 19) followed by vomiting, nausea, lymphocytopenia and leukopenia. On magnetic resonance imaging, enlargement of and contrast-enhancement clearing within the target lesion repeatedly occurred after each G47∆ administration, which was characteristic to this therapy. Thus, the best overall response in 2 yr was partial response in one patient and stable disease in 18 patients. Biopsies revealed increasing numbers of tumor-infiltrating CD4+/CD8+ lymphocytes and persistent low numbers of Foxp3+ cells. This study showed a survival benefit and good safety profile, which led to the approval of G47∆ as the first oncolytic virus product in Japan.

Hyperglycemia and intramyocardial hemorrhage in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Hyperglycemia at admission and intramyocardial hemorrhage (IMH) are associated with poor prognosis in patients with ST-segment elevation myocardial infarction (STEMI). Little is known about the relationship between glucose levels at admission and IMH. The association between matrix metalloproteinase-9 (MMP-9), which plays an important role in the development of IMH, and hyperglycemia is also unknown. This study aimed to investigate the relationship between hyperglycemia at admission and IMH in patients with STEMI. METHODS: We enrolled 174 patients with first STEMI who underwent primary percutaneous coronary intervention (PCI) and cardiovascular magnetic resonance (CMR) imaging. T2-weighted imaging and late gadolinium enhancement (LGE)-CMR were performed to detect IMH and microvascular obstruction (MVO), respectively. Two patient groups were created: IMH group and non-IMH group. MMP-9 levels were measured in the culprit coronary arteries of 13 patients. RESULTS: Glucose level at admission and the value of glycosylated hemoglobin were higher in the IMH group than in the non-IMH group [IMH group vs. non-IMH group; 208.5 (157.8-300.5) mg/dL vs. 157.0 (128.8-204.3) mg/dL, p < 0.001, and 6.2 (5.7-7.5) % vs. 5.8 (5.4-6.6) %, p = 0.030, respectively]. A multivariable logistic regression analysis revealed that only admission glucose level was an independent predictor of IMH (OR: 1.012; 95 % CI: 1.005-1.020, p = 0.001). The MMP-9 levels in patients with IMH were higher than those in patients without IMH [256.0 (161.0-396.0) ng/mL vs. 73.5 (49.5-131.0) ng/mL, p = 0.040]. There was a moderate positive correlation between glucose levels at admission and MMP-9 levels (r = 0.600, p = 0.030). CONCLUSIONS: Hyperglycemia at admission is associated with the occurrence of IMH in patients with STEMI.

Acute coronary syndrome due to plaque erosion likely triggered by insect bites: a case series of Kounis syndrome.

Background: Kounis syndrome is the concurrence of acute coronary syndrome (ACS), including coronary spasm, acute myocardial infarction, and stent thrombosis due to an allergic and/or anaphylactoid insult. Case summary: We present two cases of Kounis syndrome likely triggered by insect bites, with plaque erosion demonstrated using optical coherence tomography (OCT). Three common findings were derived from this case series. First, the patients developed a rash after an insect bite followed by ACS. Second, immunoglobulin E levels were increased. Finally, OCT identified the aetiology of ACS in this case series as erosion of the culprit lesions. Discussion: Kounis syndrome, which is ACS following allergic reactions due to insect bites, is a rare complication. Kounis syndrome is probably not uncommon, but underdiagnosed. It is important for physicians to consider the treatment of Kounis syndrome in the complex course of ACS associated with allergic reactions. Furthermore, patients with a history of Kounis syndrome should avoid antigen exposure during secondary prophylaxis. In some cases, it may take several days from antigen exposure to the onset of ACS. Considering Kounis syndrome is beneficial for early diagnosis and appropriate treatment.

Vascular Response After Everolimus-Eluting Stent in Acute Myocardial Infarction Caused by Calcified Nodule.

BACKGROUND: Patients with acute myocardial infarction (AMI) caused by calcified nodules (CN) have worse clinical outcomes following primary percutaneous coronary intervention (PCI). This study investigated the late vascular response after everolimus-eluting stent (EES) implantation assessed by optical coherence tomography (OCT) in patients with AMI caused by CN, by comparing with plaque rupture (PR) and plaque erosion (PE).Methods and Results: Based on the OCT findings in AMI culprit lesions before PCI, a total of 141 patients were categorized into 3 groups (PR, PE, or CN), and the OCT findings immediately and 10 months after PCI were compared. The frequency of PR, PE, and CN was 85 (60%), 45 (32%), and 11 patients (8%), respectively. In the 10-month follow-up OCT, the frequency of lesions with uncovered struts and lesions with malapposed struts were highest in the CN group, followed by the PR and PE groups (82% vs. 52% vs. 40%, P=0.042 and 73% vs. 26% vs. 16%, P<0.001, respectively). The incidence of intra-stent thrombus, re-appearance of CN within the stent, and target lesion revascularization were higher in the CN group compared with the PR and PE groups (36% vs. 9% vs. 7%, P=0.028; 27% vs. 0% vs. 0%, P<0.001; and 18% vs. 2% vs. 2%, P=0.024, respectively). CONCLUSIONS: Late arterial healing response at 10 months after EES implantation in the CN was worse compared with PR and PE in patients with AMI.

Usefulness of Cardiovascular Magnetic Resonance Imaging in a Patient with Cardiac Involvement of Systemic Sclerosis.

A 72-year-old Japanese woman with systemic sclerosis was admitted to our hospital because of symptoms of heart failure. Cardiovascular magnetic resonance (CMR) imaging had shown that extensive myocardial fibrosis secondary to systemic sclerosis was the main cause of heart failure. One month after CMR, she had complete atrioventricular (AV) block. It was suggested that the progression of fibrosis to the AV node caused complete AV block. This case report has clinical implications in highlighting the fact that CMR is useful for not only evaluating the present pathophysiology but also predicting future adverse events in patients with systemic sclerosis.

Usefulness of optical coherence tomography with angiographic coregistration in the guidance of coronary stent implantation.

Optical coherence tomography (OCT)-angiography coregistration during stent implantation may be useful to avoid geographical mismatch and incomplete lesion coverage. Untreated lipid-rich plaque at stent edge is associated with subsequent stent edge restenosis. The present study sought to compare the frequency of untreated lipid-rich plaque at the stent edge between OCT-guided percutaneous coronary intervention (PCI) with and without OCT-angiography coregistration. We investigated 398 patients who underwent OCT-guided stent implantation (n = 198 in the coregistration group, and n = 200 in the no coregistration group). In OCT after PCI, untreated lipid-lich plaque was identified by the maximum lipid arc > 180˚ in the 5-mm stent edge segment. The PCI-targeted lesion characteristics and stent length were not different between the coregistration group and the no coregistration group. The frequency of untreated lipid-rich plaque in either proximal or distal stent edge segment was significantly lower in the coregistration group than in the no coregistration group (16% vs. 26%, P = 0.015). The frequency of stent-edge dissection (5% vs. 6%, P = 0.516) and untreated stenosis (2% vs. 3%, P = 0.724) was low and without significant differences between the two groups. In OCT-guided PCI, the use of OCT-angiography coregistration was associated with a reduced frequency of untreated lipid-rich plaque at stent edges. OCT-angiography coregistration has a positive impact on PCI results.

Oncolytic virotherapy with human telomerase reverse transcriptase promoter regulation enhances cytotoxic effects against gastric cancer.

[This retracts the article DOI: 10.3892/ol.2021.12751.].

Intimal thickening and disruption of the media occur in the arterial walls of coronary arteries not associated with coronary arterial aneurysms in patients with Kawasaki disease.

BACKGROUND: Coronary artery aneurysm (CAA) is an important complication of Kawasaki disease (KD) that is associated with arterial structure damage. However, few studies have examined structural changes in coronary arteries that are not associated with CAA. METHODS: We examined coronary arteries in KD patients with CAAs who underwent follow-up coronary angiography (CAG) and optical coherence tomography (OCT). Coronary arterial branches with no abnormal findings during the most recent CAG were classified into two groups. Arteries with an acute-phase CAA that later regressed were classified as group R; arteries with no abnormal findings on either acute or convalescent phase CAG were classified as group N. Coronary arterial wall structural changes were compared between groups using OCT. RESULTS: Fifty-seven coronary arterial branches in 23 patients were evaluated by OCT. Thirty-six branches showed no abnormality during the most recent CAG. Both groups R and N comprised 18 branches. Maximum intimal thicknesses in groups R and N were 475 and 355 µm, respectively (p = 0.007). The incidences of media disruption were 100% and 67%, respectively (p = 0.02). Calcification, macrophage accumulation, and thrombus were not found in either group. CONCLUSIONS: Intimal thickening and disruption of the media occur in coronary arteries with acute phase CAAs that later regress in the convalescent phase, as well as in arteries with normal CAG findings in the acute and convalescent phases.

Near-infrared spectroscopy to predict microvascular obstruction after primary percutaneous coronary intervention.

BACKGROUND: Successful restoration of epicardial coronary artery patency by primary percutaneous coronary intervention (PPCI) for ST-elevation myocardial infarction (STEMI) does not always lead to adequate reperfusion at the microvascular level. AIMS: This study sought to investigate the association between lipid-rich coronary plaque identified by near-infrared spectroscopy combined with intravascular ultrasound (NIRS-IVUS) and microvascular obstruction (MVO) detected by cardiac magnetic resonance imaging (MRI) after PPCI for STEMI. METHODS: We investigated 120 patients with STEMI undergoing PPCI. NIRS-IVUS was used to measure the maximum lipid core burden index in 4 mm (maxLCBI4 mm) in the infarct-related lesions before PPCI. Delayed contrast-enhanced cardiac MRI was performed to evaluate MVO one week after PPCI. RESULTS: MVO was identified in 40 (33%) patients. MaxLCBI4 mm in the infarct-related lesion was significantly larger in the MVO group compared with the no-MVO group (median [interquartile range]: 745 [522-853] vs 515 [349-698], p<0.001). A multivariable logistic regression model showed that maxLCBI4 mm was an independent predictor of MVO (odds ratio: 24.7 [95% confidence interval: 2.5-248.0], p=0.006). Receiver operating characteristic curve analysis demonstrated that maxLCBI4 mm >600 was the optimal cut-off value to predict MVO (Youden index=0.44 and area under the curve=0.71) with a sensitivity of 75% and a specificity of 69%. CONCLUSIONS: Lipid content measured by NIRS in the infarct-related lesions was associated with the occurrence of MVO after PPCI in STEMI.