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 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.

Impact of Optical Coherence Tomography Imaging on Decision-Making During Percutaneous Coronary Intervention in Patients Presented With Acute Coronary Syndromes.

BACKGROUND: Optical coherence tomography (OCT) provides valuable information to guide percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS) regarding lesion preparation, stent sizing, and optimization. The aim of the present study was to compare lumen expansion of stent-treated lesions immediately after the procedure for ACS between OCT-guided PCI and angiography-guided PCI.Methods and Results:This study investigated stent-treated lesions immediately after PCI for ACS by using quantitative coronary angiography in 390 patients; 260 patients with OCT-guided PCI and 130 patients with angiography-guided PCI. Before stenting, the frequency of pre-dilatation and thrombus aspiration were not different between the OCT-guided and angiography-guided PCI groups. Stent diameter was significantly larger as a result of OCT-guided PCI (3.11±0.44 mm vs. 2.99±0.45 mm, P=0.011). In post-dilatation, balloon pressure-up (48% vs. 31%, P=0.001) and balloon diameter-up (33% vs. 6%, P<0.001) were more frequently performed in the OCT-guided PCI group. Minimum lumen diameter (2.55±0.35 mm vs. 2.13±0.50 mm, P<0.001) and acute lumen gain (2.18±0.54 mm vs. 1.72±0.63 mm, P<0.001) were significantly larger in the OCT-guided PCI group. Percent diameter stenosis (14±4% vs. 24±10%, P<0.001) and percent area stenosis (15±5% vs. 35±17%, P<0.001) were significantly smaller in the OCT-guided PCI group. CONCLUSIONS: OCT-guided PCI potentially results in larger lumen expansion of stent-treated lesions immediately after PCI in the treatment of ACS compared with angiography-guided PCI.

Impact of left ventricular ejection fraction and preoperative hemoglobin level on perioperative adverse cardiovascular events in noncardiac surgery.

The prediction of a perioperative adverse cardiovascular event (PACE) is an important clinical issue in the medical management of patients undergoing noncardiac surgery. Although several predictors have been reported, simpler and more practical predictors of PACE have been needed. The aim of this study was to investigate the predictors of PACE in noncardiac surgery. We retrospectively analyzed 723 patients who were scheduled for elective noncardiac surgery and underwent preoperative examinations including 12-lead electrocardiography, transthoracic echocardiography, and blood test. PACE was defined as cardiac death, non-fatal myocardial infarction, unstable angina, congestive heart failure, arrhythmia attack that needs emergency treatment (rapid atrial fibrillation, ventricular tachycardia, and bradycardia), acute pulmonary embolism, asystole, pulseless electrical activity, or stroke during 30 days after surgery. PACE occurred in 54 (7.5%) of 723 patients. High-risk operation (11% vs. 3%, p = 0.003) was more often seen, left ventricular ejection fraction (LVEF) (55 ± 8% vs. 60 ± 7%, p = 0.001) and preoperative hemoglobin level (11.8 ± 2.2 g/dl vs. 12.7 ± 2.0 g/dl, p = 0.001) were lower in patients with PACE compared to those without PACE. By multivariate logistic regression analysis, high-risk operation (odds ratio (OR): 7.05, 95% confidence interval (CI) 2.16-23.00, p = 0.001), LVEF (OR 1.06, every 1% decrement, 95% CI 1.03-1.09, p = 0.001), and preoperative hemoglobin level (OR 1.22, every 1 g/dl decrement, 95% CI 1.07-1.39, p = 0.003) were identified as independent predictors of PACE. Receiver operating characteristic analysis demonstrated that LVEF of 58% (sensitivity = 80%, specificity = 61%, area under the curve (AUC) = 0.723) and preoperative hemoglobin level of 12.2 g/dl (sensitivity = 63%, specificity = 64%, AUC = 0.644) were optimal cut-off values for predicting PACE. High-risk operation, reduced LVEF, and reduced preoperative hemoglobin level were independently associated with PACE in patients undergoing noncardiac surgery.

Optical Coherence Tomography Comparison of Percutaneous Coronary Intervention Among Plaque Rupture, Erosion, and Calcified Nodule in Acute Myocardial Infarction.

BACKGROUND: Acute myocardial infarction (AMI) is caused by coronary plaque rupture (PR), plaque erosion (PE), or calcified nodule (CN). We used optical coherence tomography (OCT) to compare stent expansion immediately after primary percutaneous coronary intervention (PCI) in patients with AMI caused by PR, PE, or CN.Methods and Results:In all, 288 AMI patients were assessed by OCT before and immediately after PCI, performed with OCT guidance according to OPINION criteria for stent sizing and optimization. The frequency of OCT-identified PR (OCT-PR), OCT-PE, and OCT-CN was 172 (60%), 82 (28%), and 34 (12%), respectively. Minimum stent area was smallest in the OCT-CN group, followed by the OCT-PE and OCT-PR groups (mean [±SD] 5.20±1.77, 5.44±1.78, and 6.44±2.2 mm2, respectively; P<0.001), as was the stent expansion index (76±13%, 86±14%, and 87±16%, respectively; P=0.001). The frequency of stent malapposition was highest in the OCT-CN group, followed by the OCT-PR and OCT-PE groups (71%, 38%, and 27%, respectively; P<0.001), as was the frequency of stent edge dissection in the proximal reference (44%, 23%, and 10%, respectively; P<0.001). The frequency of tissue protrusion was highest in the OCT-PR group, followed by the OCT-PE and OCT-CN groups (95%, 88%, and 85%, respectively; P=0.036). CONCLUSIONS: Stent expansion was smallest in the OCT-CN group, followed by the OCT-PR and OCT-PE groups. Plaque morphology in AMI culprit lesions may affect stent expansion immediately after primary PCI.

Comparison of Optical Flow Ratio and Fractional Flow Ratio in Stent-Treated Arteries Immediately After Percutaneous Coronary Intervention.

BACKGROUND: Optical flow ratio (OFR) is a recently developed method for functional assessment of coronary artery disease based on computational fluid dynamics of vascular anatomical data from intravascular optical coherence tomography (OCT). The purpose of this study was to investigate the relationship between OFR and fractional flow reserve (FFR) in stent-treated arteries immediately after percutaneous coronary intervention (PCI).Methods and Results:The OFR and FFR were measured in 103 coronary arteries immediately after successful PCI with a stent. An increase in the OFR and FFR values within the stent was defined as in-stent ∆OFR and ∆FFR, respectively. The values of FFR and OFR were 0.89±0.06 and 0.90±0.06, respectively. OFR was highly correlated with FFR (r=0.84, P<0.001). OFR showed a good agreement with FFR, presenting small values of mean difference and root-mean-squared deviation (FFR-OFR: -0.01±0.04). In-stent ∆OFR showed a moderate correlation (r=0.69, P<0.001) and good agreement (in-stent ∆FFR - in-stent ∆OFR: 0.00±0.02) with in-stent ∆FFR. CONCLUSIONS: OFR showed a high correlation and good agreement with FFR in stent-treated arteries immediately after PCI.

Retrospective Comparison of Long-Term Clinical Outcomes Between Percutaneous Coronary Intervention and Medical Therapy in Stable Coronary Artery Disease With Gray Zone Fractional Flow Reserve　- COMFORTABLE Retrospective Study.

BACKGROUND: A fractional flow reserve (FFR) between 0.75 and 0.80 constitutes a "gray zone" for clinical decision-making in coronary artery disease. We compared long-term outcomes of percutaneous coronary intervention (PCI) using drug-eluting stents vs. medical therapy for coronary stenosis with gray zone FFR. Methods and Results: We retrospectively investigated the clinical outcomes of 263 patients with gray zone FFR: 78 patients in the PCI group and 185 patients in the medical therapy group. During a median follow-up of 3.7 years, the frequency of target vessel failure (TVF, defined as a composite of cardiac death, myocardial infarction [MI], or ischemia-driven target vessel revascularization [TVR]) was significantly lower in the PCI group compared with the medical therapy group (6% vs. 19%, hazard ratio [HR]:0.33, 95% confidence interval [CI]: 0.13-0.84, P=0.008). The frequency of a composite of cardiac death or MI was not different between the 2 groups (1% vs. 2%, HR: 0.61, 95% CI: 0.07-5.49, P=0.645). The frequency of ischemia-driven TVR was significantly lower in the PCI group compared with the medical therapy group (5% vs. 18%, HR: 0.28, 95% CI: 0.10-0.79, P=0.005). CONCLUSIONS: In patients with gray zone FFR, compared with medical therapy, PCI decreased the frequency of TVF, which was mainly driven by a reduction in the frequency of angina or myocardial ischemia without any difference in the frequency of cardiac death or MI.

Intracoronary Near-Infrared Spectroscopy to Predict No-Reflow Phenomenon During Percutaneous Coronary Intervention in Acute Coronary Syndrome.

Near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) can identify the lipid-rich lesions, described as high lipid-core burden index (LCBI). The aim of this study was to investigate the relation between lipid-core plaque (LCP) in the infarct-related lesion detected using NIRS-IVUS and no-reflow phenomenon during percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS). We investigated 371 patients with ACS who underwent NIRS-IVUS in the infarct-related lesions before PCI. The extent of LCP in the infarct-related lesion was calculated as the maximum LCBI for each of the 4-mm longitudinal segments (maxLCBI4mm) measured by NIRS-IVUS. The patients were divided into 2 groups using a maxLCBI4mm cut-off value of 400. The overall incidence of no-reflow phenomenon was 53 of 371 (14.3%). No-reflow phenomenon more frequently occurred in patients with maxLCBI4mm ≥400 compared with those with maxLCBI4mm<400 (17.5% vs 2.5%, p <0.001). After propensity score matching, multivariable logistic regression analysis demonstrated that maxLCBI4mm (odds ratio: 1.008; 95% confidence interval: 1.005 to 1.012, p <0.001) was independently associated with the no-reflow phenomenon. The maxLCBI4mm of 719 in the infarct-related lesion had the highest combined sensitivity (69.8%) and specificity (72.1%) for the identification of no-reflow phenomenon. In conclusion, in patients with ACS, maxLCBI4mm in the infarct-related lesion assessed by NIRS-IVUS was independently associated with the no-reflow phenomenon during PCI.

Left ventricular reverse remodeling and reduction of interstitial fibrosis in patients with severe aortic stenosis who underwent transcatheter aortic valve implantation.

BACKGROUND: Left ventricular (LV) structural and functional changes have been reported in patients with aortic stenosis (AS) who have undergone transcatheter aortic valve implantation (TAVI); however, the relationship between change in LV structure and systolic function and tissue characteristics assessed via cardiovascular magnetic resonance imaging (CMRI) post-TAVI has been not fully elucidated. This study aimed to investigate this relationship in patients with severe AS who underwent TAVI and CMRI. METHODS: In this retrospective study, 65 patients who underwent TAVI and CMRI at the 6-month follow-up were analyzed. The relationship between percent changes in LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV ejection fraction (LVEF), and LV mass (LVM) (⊿LVEDV, ⊿LVESV, ⊿LVEF, and ⊿LVM) and those in the native T1 value (⊿native T1) was analyzed using a correlation analysis. Moreover, extracellular volume fraction (ECV) value changes were analyzed. RESULTS: The ⊿native T1 significantly decreased from 1292.8 (1269.9-1318.4) ms at pre-TAVI to 1282.3 (1262.6-1310.2) ms at the 6-month follow-up (P = 0.022). A significant positive correlation between ⊿LVEDV, ⊿LVESV, and ⊿LVM and ⊿native T1 (r = 0.351, P = 0.004; r = 0.339, P = 0.006; r = 0.261, P = 0.035, respectively) and a tendency toward a negative correlation between ⊿LVEF and ⊿native T1 (r = -0.237, P = 0.058) were observed. The ECV value increased significantly from 26.7 % (25.3-28.3) to 28.2 % (25.7-30.5) (P = 0.002). CONCLUSIONS: The decrease in native T1 might be associated with LV reverse remodeling. Evaluating structural and functional changes using CMRI may be useful for patient management.

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.

Risk factors for unsuccessful restoration of coronary flow reserve after coronary bypass surgery.

OBJECTIVES: Coronary flow reserve (CFR) is a strong predictor of cardiovascular events and prognosis in patients with coronary artery disease. This study aimed to evaluate preoperative factors associated with the unsuccessful restoration of CFR after coronary artery bypass grafting (CABG). METHODS: Included in this study were the 65 patients who presented with functionally significant left anterior descending artery (LAD) lesions confirmed by both fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR), and who underwent successful CABG at our hospital within the study period. After CABG, graft patency was confirmed by coronary computed tomography angiography, and CFR in the LAD artery was measured by echocardiography. We defined postoperative CFR <2.5 as impaired CFR, and CFR ≥2.5 as preserved CFR. RESULTS: Of the 65 patients, 14 patients (22%) showed impaired CFR, while 51 patients had preserved CFR. Patients with impaired CFR had significantly higher HbA1c (6.7% vs. 6.0%, P < 0.01), greater use of insulin (43% vs. 4%, P < 0.01), longer lesion length (33 mm vs. 25 mm, P = 0.044), and lower iFR (0.69 vs 0.81, P = 0.01) than those with preserved CFR, although both groups had comparable FFR (0.65 vs 0.64, P = 0.46). In receiver operating characteristic curve analysis, iFR had a significantly larger area under the curve than FFR in terms of the prediction of impaired CFR (0.74 vs 0.42, P = 0.01). CONCLUSIONS: Poorly-controlled preoperative diabetes, greater reliance on insulin, longer lesion length and lower iFR were associated with postoperative impaired CFR, suggesting the involvement of microvascular dysfunction.

Impact of Climate on the Incidence of Acute Coronary Syndrome　- Differences Between Japan and Thailand.

Background: Although there are many reports of temperature being associated with the onset of acute coronary syndrome (ACS), few studies have examined differences in ACS due to climatic differences between Japan and Thailand. The aim of this joint Japan-Thailand study was to compare patients with myocardial infarction in Japanese and Thai hospitals in different climates. Methods and Results: We estimated the climate data in 2021 for the Wakayama Prefecture and Chonburi Province, two medium-sized cities in Japan and Thailand, respectively, and ACS patients who were treated at the Wakayama Medical University (WMU) and Burapha University Hospital (BUH), the two main hospitals in these provinces (ACS patient numbers: WMU, n=177; BUH, n=93), respectively. In the Chonburi Province, although the average temperature was above 25℃, the number of ACS cases in BUH varied up to threefold between months (minimum: July, 4 cases; maximum: October, 14 cases). In Japan and Thailand, there was a mild to moderate negative correlation between temperature-atmospheric pressure at the onset of ACS, but different patterns for temperature-humidity (temperature-atmospheric pressure, temperature-humidity, and atmospheric pressure-humidity: correlation index; r=-0.561, 0.196, and -0.296 in WMU vs. r=-0.356, -0.606, and -0.502 in BUH). Conclusions: The present study suggests that other climatic conditions and factors, not just temperature, might be involved in the mechanism of ACS.

Artificial Intelligence-Enabled Quantitative Coronary Plaque and Hemodynamic Analysis for Predicting Acute Coronary Syndrome.

BACKGROUND: A lesion-level risk prediction for acute coronary syndrome (ACS) needs better characterization. OBJECTIVES: This study sought to investigate the additive value of artificial intelligence-enabled quantitative coronary plaque and hemodynamic analysis (AI-QCPHA). METHODS: Among ACS patients who underwent coronary computed tomography angiography (CTA) from 1 month to 3 years before the ACS event, culprit and nonculprit lesions on coronary CTA were adjudicated based on invasive coronary angiography. The primary endpoint was the predictability of the risk models for ACS culprit lesions. The reference model included the Coronary Artery Disease Reporting and Data System, a standardized classification for stenosis severity, and high-risk plaque, defined as lesions with ≥2 adverse plaque characteristics. The new prediction model was the reference model plus AI-QCPHA features, selected by hierarchical clustering and information gain in the derivation cohort. The model performance was assessed in the validation cohort. RESULTS: Among 351 patients (age: 65.9 ± 11.7 years) with 2,088 nonculprit and 363 culprit lesions, the median interval from coronary CTA to ACS event was 375 days (Q1-Q3: 95-645 days), and 223 patients (63.5%) presented with myocardial infarction. In the derivation cohort (n = 243), the best AI-QCPHA features were fractional flow reserve across the lesion, plaque burden, total plaque volume, low-attenuation plaque volume, and averaged percent total myocardial blood flow. The addition of AI-QCPHA features showed higher predictability than the reference model in the validation cohort (n = 108) (AUC: 0.84 vs 0.78; P < 0.001). The additive value of AI-QCPHA features was consistent across different timepoints from coronary CTA. CONCLUSIONS: AI-enabled plaque and hemodynamic quantification enhanced the predictability for ACS culprit lesions over the conventional coronary CTA analysis. (Exploring the Mechanism of Plaque Rupture in Acute Coronary Syndrome Using Coronary Computed Tomography Angiography and Computational Fluid Dynamics II [EMERALD-II]; NCT03591328).

Bactericidal activity of garenoxacin against in vitro biofilm formed by nontypeable Haemophilus influenzae.

Using ß-lactamase-negative ampicillin (ABPC)-susceptible (BLNAS) and ß-lactamase-negative ABPC-resistant (BLNAR) nontypeable Haemophilus influenzae (NTHi) strains isolated from otological patients, colony biofilm was prepared on membrane filter substrates. Bactericidal activities of garenoxacin (GRNX), levofloxacin (LVFX), cefditoren (CDTR), and clavulanic acid/amoxicillin (CVA/AMPC) were examined by counting viable cells after drug exposure to biofilm cells for 6 and 24 h and by observation under a scanning electron microscope (SEM). After exposure of biofilm to the 100-fold MIC of GRNX or LVFX for 24 h, GRNX and LVFX showed potent bactericidal activity (∆log10 CFU/ml, ≥5.1). In this case, the drug-exposure AUC, exposure concentration × 24 µg h/ml, was 64-128 % for GRNX and 121 % for LVFX of free AUC at the clinical dosage in humans, respectively. CDTR and CVA/AMPC at 100-fold MIC exhibited little bactericidal activity against biofilm cells. Under an SEM, after exposure of BLNAS and BLNAR biofilms to GRNX or LVFX, most of the biofilm matrices were transformed. Quinolones such as GRNX show potent bactericidal activity against biofilm-forming NTHi at the usual clinical dosage.

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.

Prevalence of low-attenuation plaques and statin therapy in plaque rupture type of acute coronary syndrome.

BACKGROUND: We sought to investigate the differences in coronary plaque morphology on coronary computed tomography angiography (CCTA) and medical therapy between acute coronary syndrome (ACS) and stable ischemic heart disease (SIHD). We also explored the relationship between plaque morphology on CCTA at the initial phase and lesion morphology in the acute phase of ACS. METHODS: In 5967 patients who underwent invasive coronary angiography, 58 ACS and 91 SIHD patients who had prior CCTA imaging of the culprit lesion and denied ischemic heart disease at CCTA scanning were enrolled. RESULTS: Although the prevalence of positive remodeling was not different (P = 0.27), low-attenuation plaques (LAP) on prior CCTA were significantly higher in ACS than in SIHD (52% vs. 24%, P < 0.01). The frequency of coronary stenosis grading did not differ between the two groups (P = 0.14). In ACS patients, the frequencies of plaque rupture and lipid-rich plaque assessed by optical coherence tomography (OCT) were significantly higher in LAP than in non-LAP (73% vs. 23%, P < 0.01; 82% and 23%, P < 0.01). Multivariate regression analysis revealed that statin use and LAP on prior CCTA were predictors of future ACS events (P < 0.01, and P < 0.05, respectively). CONCLUSIONS: LAP on CCTA, not positive arterial remodeling, and lack of statin therapy were associated with ACS development. In addition, LAP more frequently led to the development of the plaque rupture type of ACS compared with non-LAP. Lipid-lowering therapy with statins might be useful to prevent plaque rupture in patients with LAP regardless of coronary stenosis.

Diagnostic significance of paradoxical left ventricular hypertrophy in detecting cardiac amyloidosis.

Background: Cardiac amyloidosis (CA) progresses rapidly with a poor prognosis. Therefore, methods for early diagnosis that are easily accessible in any hospital, are required. We hypothesized that based on the pathology of CA, morphological left ventricular hypertrophy (LVH) without electrical augmentation, namely paradoxical LVH, could be used to diagnose CA. This study aimed to investigate whether paradoxical LVH has diagnostic significance in identifying CA in patients with LVH. Methods: Patients who presented with left ventricular (LV) wall thickness ≥ 12 mm on cardiac magnetic resonance (CMR) were enrolled from a multicentre CMR registry. Paradoxical LVH was defined as a LV wall thickness ≥ 12 mm on CMR, SV1 + RV5 < 3.5 mV, and a lack of secondary ST-T abnormalities. The diagnostic significance of paradoxical LVH in identifying CA was assessed. Results: Of the 110 patients enrolled, 30 (27 %) were diagnosed with CA and 80 (73 %) with a non-CA aetiology. The CA group demonstrated paradoxical LVH more frequently than the non-CA group (80 % vs. 16 %, P < 0.001). It was an independent predictor for detecting CA in patients with LVH (odds ratio: 33.44, 95 % confidence interval: 8.325-134.3, P < 0.001). The sensitivity, specificity, positive predict value, negative predict value and accuracy of paradoxical LVH for CA detection were 80 %, 84 %, 65 %, 92 % and 83 %, respectively. Conclusions: Paradoxical LVH can be used for identifying CA in patients with LVH. Our findings could contribute to the early diagnosis of CA, even in non-specialized hospitals.

Inhibitory activity of garenoxacin against DNA gyrase of Mycoplasma pneumoniae.

OBJECTIVES: Garenoxacin, a des-fluoro(6)-quinolone, exhibits potent activity against Mycoplasma pneumoniae, including macrolide-resistant strains. There has been no report on the inhibitory activity of garenoxacin against the target enzyme of M. pneumoniae. METHODS: Subunits of DNA gyrase (GyrA and GyrB) proteins of M. pneumoniae FH were separately expressed as His-tagged proteins in Escherichia coli Chaperone Competent Cell BL21 by IPTG induction of plasmids containing the respective gyrA and gyrB genes. The inhibitory activities of garenoxacin, moxifloxacin, gatifloxacin and levofloxacin against DNA gyrase were evaluated by the inhibition of supercoiling activity (n = 3). RESULTS: Against M. pneumoniae FH, garenoxacin showed 2- to 16-fold more potent activity than the other quinolones. The mean IC(50) of garenoxacin for DNA gyrase of M. pneumoniae was 2.5 mg/L. Garenoxacin showed the most potent inhibitory activity against M. pneumoniae DNA gyrase among the quinolones tested. The IC(50) values of the quinolones for DNA gyrase roughly correlated with each MIC value. CONCLUSIONS: The antimycoplasmal activity of the quinolones was almost certainly due to inhibition of the supercoiling activity of DNA gyrase. Garenoxacin was considered a valuable quinolone in the treatment of infectious diseases caused by M. pneumoniae.