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SummaryBackgroundTissue characteristics of coronary plaques can be evaluated using integrated backscatter intravascular ultrasound (IB-IVUS), while fractional flow reserve (FFRmyo) is an index of functional coronary stenosis. We assessed the relation between functional stenosis and the characteristics of plaque tissue using FFRmyo and IB-IVUS.Methods and resultsA total of 17 lesions with 75%-stenosis assessed visually by coronary angiography from 17 stable angina patients (64.2±9.1 years old, 11 males) were studied. IB-IVUS was evaluated in the most stenotic cross-sectional area. Using commercially available software, coronary plaques were assessed for calcification (CA), fibrosis (F), and lipid pool (LP). Lesions were localized in the left anterior descending artery in 11 patients, the left circumflex in 3, and the right coronary artery in 3. On quantitative coronary angiography, the percent diameter stenosis (%DS) was 60.5±7.3%. Plaque burden was 71.4±9.1%, FFRmyo was 0.74±0.13. The tissue component of the plaques was: CA(%), 3.0±2.4%; F(%), 60.5±9.6%; LP(%), 37.2±11.0%. Significant correlation was not observed between %DS or plaque burden and FFRmyo, structural stenosis and plaque characterization, nor between CA(%) and FFRmyo. There was a positive correlation between F(%) and FFRmyo (r=0.62, p

SummaryObjectivesTreatment of mitral valve stenosis with catheter balloon commissurotomy (CBC) yields acceptable immediate results even when one commissure shows calcification. However, the long-term outcomes in such cases remain unclear.MethodsWe examined the immediate and long-term (mean: 11±5 years) outcomes of 57 patients who underwent 58 CBC procedures. Patients were classified into group A (no commissural calcification, n=44) or group B (unilateral commissural calcification, n=13). From the appearance of the mitral valve just after CBC, commissurotomy was judged to be bilateral, incomplete, or excessive. End points were death, recurrence of congestive heart failure necessitating hospitalization, embolism, repeat CBC, or mitral valve replacement.ResultsThere were significant numbers of unfavorable mitral valve morphologies evaluated according to Sellors classification, estimated by echocardiograms; Sellors class I: 20 patients in group A vs. none in group B (p

Because mitochondria play pivotal roles in both insulin secretion from the pancreatic beta cells and insulin resistance of skeletal muscles, we performed a large-scale association study to identify mitochondrial haplogroups that may confer resistance against or susceptibility to type 2 diabetes mellitus (T2DM). The study population comprised 2,906 unrelated Japanese individuals, including 1,289 patients with T2DM and 1,617 controls, and 1,365 unrelated Korean individuals, including 732 patients with T2DM and 633 controls. The genotypes for 25 polymorphisms in the coding region of the mitochondrial genome were determined, and the haplotypes were classified into 10 major haplogroups (i.e., F, B, A, N9a, M7a, M7b, G, D4a, D4b, and D5). Multivariate logistic-regression analysis with adjustment for age and sex revealed that the mitochondrial haplogroup N9a was significantly associated with resistance against T2DM (P=.0002) with an odds ratio of 0.55 (95% confidence interval 0.40-0.75). Even in the modern environment, which is often characterized by satiety and physical inactivity, this haplogroup might confer resistance against T2DM.

Mitochondrion-derived reactive oxygen species possibly play an important role in the pathogenesis of atherosclerosis and atherothrombotic cerebral infarction, because mitochondria in vascular endothelial cells are the major site of superoxide production. In the present study, we surveyed mitochondrial haplogroups associated with atherothrombotic cerebral infarction in 1081 Japanese subjects. Twenty-six mitochondrial single nucleotide polymorphisms of 11 major mitochondrial haplogroups (F, B, A, N9a, M7a, M7b, M7c, G1, G2, D4, and D5) were determined by use of 28-plex PCR and fluorescent beads combined with sequence-specific oligonucleotide probes. Multivariate logistic regression analysis with adjustment for conventional risk factors revealed that mitochondrial haplogroup A was associated with atherothrombotic cerebral infarction in female subjects (P

OBJECTIVES This study focused on 1) the determination of the optimal preconditioning (PC) duration, and 2) the protective effect of nicorandil (NC), a hybrid nitrate with a K atp channel opening effect, during a percutaneous transluminal coronary angioplasty (PTCA) model in humans. BACKGROUND The ischemic PC effect is induced in 180 s ischemia, but not in 120 s ischemia in rabbit hearts. However, the duration of ischemia that induces PC effect and the role of the K atp channel in the PC effect in humans are still unclear. METHODS Forty-six patients with stable angina were randomly allocated to four groups: the duration of the first inflation as PC ischemia was 60 s in the PC60 group (n = 12), and 180 s in the PC180 group (n = 12). In the other groups, NC (80 μg/kg) was intravenously given for 1 min in the NC group (n = 12), and isosorbide dinitrate (ISDN) (40 μg/kg) was given in the ISDN group (n = 10). Five minutes after first inflation or drug administration, a second inflation was conducted for 120 s in each group. In the ECG, the lead with the largest shift in ST segment (deltaST max), and the sum of elevated ST levels in all leads (sigmaST) were determined. RESULTS In the PC60 group, no significant difference was observed in either deltaST max or sigmaST between the first and second inflation. However, the second inflation in the PC180 group showed significantly lower levels of deltaST max and sigmaST compared with those of the first inflation. In the NC group, both deltaST max and sigmaST measured at 30 s and 60 s after balloon inflation were significantly lower than those of the first inflation in the PC60 and PC180 control groups. In the ISDN group, no significant difference was observed in deltaST max or sigmaST. CONCLUSION In human PTCA models, a PC effect is observed in 180 s ischemia, but not in 60 s ischemia. A pharmacological PC effect is induced by NC, a K atp channel opener with a nitrate-like effect but not ISDN. This suggests that the opening of K atp channels plays an important role in the protecting effect of NC.