Daiju Fukuda

Implications of plasma concentrations of adiponectin in patients with coronary artery disease

Objective: To investigate whether concentrations of plasma adiponectin constitute a significant coronary risk factor, with particular focus on the relation between plasma concentrations of adiponectin and the development of acute coronary syndrome (ACS). Subjects and methods: Plasma concentrations of adiponectin were measured in 123 patients with coronary artery disease (CAD) and in 17 control participants. Patients were divided into three groups according to condition type: acute myocardial infarction (AMI) group (n  =  59), unstable angina pectoris (UAP) group (n  =  28), and stable angina pectoris (SAP) group (n  =  36). Results: Plasma concentrations of adiponectin correlated negatively with body mass index (r  =  −0.18, p < 0.05), serum triglyceride (r  =  −0.25, p < 0.01), and fasting glucose concentrations (r  =  −0.21, p < 0.05), but correlated positively with age (r  =  0.26, p < 0.01), high density lipoprotein cholesterol concentrations (r  =  0.35, p < 0.01), and low density lipoprotein particle size (r  =  0.37, p < 0.01). Plasma concentrations of adiponectin in patients with ACS, in both the AMI and UAP groups, were significantly lower than those in patients with SAP and in the control group (ACS, 6.5 (3.0) μg/ml; SAP, 11.3 (5.9) μg/ml; control 12.8 (4.3) μg/ml; p < 0.01). Additionally, plasma concentrations of adiponectin in patients with CAD (7.9 (4.6) μg/ml, p < 0.01) were significantly lower than in the control group. There were, however, no significant differences between patients with SAP and the control group (p  =  0.36). Multiple logistic regression analysis showed that smoking, fasting glucose concentration, and low log adiponectin concentration correlated independently with the development of an ACS. Conclusions: The findings suggest that measurement of plasma concentrations of adiponectin may be of use for assessing the risk of CAD and may be related to the development of ACS.

No-reflow phenomenon and lesion morphology in patients with acute myocardial infarction.

Background—The no-reflow phenomenon is associated with poor functional and clinical outcomes for patients with acute myocardial infarction (AMI). In the era of primary intervention, accurately identifying lesions at high risk of no reflow is of crucial importance. At present, no study into the relationship between lesion morphology and no reflow has been performed. The aim of this study was to investigate the relationship between preintervention intravascular ultrasound (IVUS) lesion morphology and the no-reflow phenomenon. Methods and Results—This study comprised 100 consecutive patients with AMI who underwent preintervention IVUS and were successfully recanalized with primary balloon angioplasty or stenting. IVUS was again performed to identify and exclude any mechanical vessel obstruction in cases of thrombolysis in myocardial infarction flow grade 0, 1, or 2 after intervention in the absence of angiographic stenosis. Angiographic no reflow was seen in 13 patients (13%). Univariate analysis indicated that hypercholesterolemia, fissure and dissection, lipid pool–like image, lesion, and reference external elastic membrane cross-sectional area correlate with the no-reflow phenomenon. Multivariate logistic regression analysis showed that lipid pool–like image (P <0.05; odds ratio 118; 95% CI, 1.28 to 11 008) and lesion elastic membrane cross-sectional area (P <0.05; odds ratio 1.55; 95% CI 1.01 to 2.38) are independent predictive factors of no-reflow phenomenon after reperfusion for AMI. Conclusions—Large vessels with lipid pool–like image are at high risk for no reflow after primary intervention for AMI. Also, plaque content may play a role in damage to the microcirculation after primary intervention for AMI.

Relation between aortic stiffness and coronary flow reserve in patients with coronary artery disease

Objectives: To investigate the relation between aortic stiffness and coronary flow reserve (CFR) in patients with coronary artery disease (CAD). Design: Observational study. Setting: Coronary care unit of a primary care hospital. Patients: 192 consecutive patients who underwent coronary angiography. Main outcome measure: Brachial-ankle pulse wave velocity (ba-PWV), CFR, and severity of CAD. Results: According to the angiographic findings, patients were divided into four subgroups: patients without significant stenosis (normal coronary artery (NCA) group, n  =  28) and those with one vessel disease (1VD group, n  =  92), two vessel disease (2VD group, n  =  50), or three vessel disease (3VD group, n  =  22). ba-PWV increased with the number of diseased vessels and was significantly correlated with the number of diseased vessels (NCA group v 1VD group v 2VD group v 3VD group: 1481 (252) v 1505 (278) v 1577 (266) v 1727 (347) cm/s, p < 0.001). CFR had a significant negative correlation with ba-PWV (r  =  −0.45, p < 0.0001). The diastolic to systolic velocity ratio obtained in 45 patients also was significantly correlated with ba-PWV (r  =  −0.35, p < 0.05). Multiple regression analysis showed that ba-PWV was an independent determinant of CFR (p < 0.01). Conclusions: Coronary flow is altered with aortic stiffening in patients with CAD. These results suggest one possible mechanism for recent reports that aortic stiffness is a key cardiovascular risk factor.

Predicting angiographic distal embolization following percutaneous coronary intervention in patients with acute myocardial infarction

The aim of this study was to investigate the relation between lesion morphology identified by intravascular ultrasound (IVUS) before intervention and angiographic distal embolization after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI). PCI for AMI has already been established as beneficial therapy, although some complications remain unresolved. Distal embolization is 1 of the important complications of PCI. Recently, some new devices have been developed for the prevention of distal embolization. However, few studies exist that look into the relation between lesion morphology and distal embolization. IVUS was performed safely in 140 consecutive patients with AMI before coronary intervention. No patient received thrombolytic therapy. From the incidence of angiographic distal embolization, patients were divided into 2 groups--an embolization group and a nonembolization group--and clinical background, IVUS, and angiographic information were evaluated. Distal embolization was observed in 12 patients (9%). Peak creatine kinase levels (3,877 +/- 2,285 vs 2,293 +/- 1,792 IU/L, p <0.05) and the incidence of angiographic thrombus (25% vs 5%, p <0.05) and intracoronary mobile mass detected by IVUS (75% vs 16%, p <0.001) were higher for patients in the embolization group. From the multivariate logistic regression analysis, only an intracoronary mobile mass detected by IVUS emerged as a predictor of distal embolization (odds ratio 53, 95% confidence interval 2.7 to 1,040, p <0.01). Patients with an intracoronary mobile mass detected by IVUS are prone to distal embolization after PCI and larger infarction. IVUS imaging before PCI may be useful for determining which patients need a distal protection device.

Lesion characteristics of acute myocardial infarction: an investigation with intravascular ultrasound

OBJECTIVE To use intravascular ultrasound (IVUS) to compare plaque morphology in acute myocardial infarction and stable angina pectoris. DESIGN Retrospective study. SETTING Primary care hospital. PATIENTS 59 consecutive cases of acute myocardial infarction and 50 consecutive cases of stable angina pectoris. METHODS IVUS was used before coronary intervention. MAIN OUTCOME MEASURES Plaque morphology (incidence of eccentric plaque, subtle dissections, low echoic thrombus, calcification, echolucent areas, and bright speckled echo material), assessed visually using IVUS. RESULTS There were no significant differences in plaque eccentricity or calcification between the two groups, but low echoic thrombus (acute myocardial infarction 15%v stable angina pectoris 0%), subtle dissections (37% v 4%), echolucent areas (31% v 0%), and bright speckled echo material (90% v 0%) were more common in the infarction group than in the stable angina group (p < 0.001 for all). There was a longer time between the onset of symptoms and the IVUS examination in patients with low echoic thrombus than in those without (p < 0.03). CONCLUSIONS Low echoic thrombus, subtle dissections, echolucent areas, and bright speckled echo material are morphological characteristics associated with plaque at the time of acute myocardial infarction. These findings correspond pathologically to ruptured plaque.

Assessment of myocardial viability using coronary zero flow pressure after successful angioplasty in patients with acute anterior myocardial infarction

Objectives: To investigate the relation between coronary flow reserve (CFR), coronary zero flow pressure (Pzf), and residual myocardial viability in patients with acute myocardial infarction. Designs: Prospective study. Setting: Primary care hospital. Patients: 27 consecutive patients with acute anterior myocardial infarction. Main outcome measures:18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) was used in 27 patients who underwent successful intervention within 12 hours of onset of a first acute anterior myocardial infarction. Within three days before discharge they had < 25% stenosis in the culprit lesion as determined by angiography 24 (3) days after acute myocardial infarction. Pzf and the slope index of the flow-pressure relation (SIFP) were calculated from the simultaneously recorded aortic pressure and coronary flow velocity signals at peak hyperaemia.%FDG was quantified by comparing FDG uptake in the infarct myocardium with FDG uptake in the normal myocardium. Results: There was a correlation between %FDG and CFR, where y = −1.477x + 62.517, r = −0.072 (NS). There was also a correlation between %FDG and SIFP, where y = −0.975x + 60.542, r = −0.045 (NS), and a significant correlation between %FDG and Pzf, where y = −0.98x + 85.108, r = −0.696 (p < 0.001). Conclusions: CFR does not correlate with FDG-PET at the time of postreperfusion evaluation of residual myocardial viability. The parameter that correlates best with residual myocardial viability is Pzf and this may be a useful index for predicting patient prognosis.