Hiroyuki Mihara

Behavioral correlates of plasma sex hormones and their relationships with plasma lipids and lipoproteins in Japanese men

In contrast to the hypothesis that endogenous testosterone decreases plasma high-density lipoprotein (HDL) cholesterol levels, many, but not all, studies have reported a positive correlation between plasma total testosterone and HDL cholesterol. We examined behavioral correlates of plasma testosterone and estradiol and the relationships between these sex hormones and plasma lipoproteins, in middle-aged Japanese men. Plasma, lipids, including HDL subfractions, total and free testosterone, and total estradiol were determined with 313 men aged 50-54 years who received a preretirement health examination at the Self-Defence Forces Fukuoka Hospital from January to June in 1992. Body mass index and waist-hip ratio were also measured. Smoking habit, alcohol use, and physical activity were ascertained by a self-administered questionnaire. Obesity, especially waist-hip ratio, was a strong correlate of both total and free testosterone, but not of estradiol. Smoking was associated with elevated levels of testosterone without a dose-effect relation. Neither alcohol use nor physical activity was associated with total or free testosterone, but plasma estradiol levels were higher among current alcohol drinkers. HDL and HDL2 cholesterol were unrelated to either total or free testosterone in the univariate analysis, but negatively associated with free, not total, testosterone after adjustment for obesity. HDL and HDL2 cholesterol also were positively associated with estradiol regardless of adjustment for obesity and other covariates. These findings add to evidence for a hypothesis that high levels of endogenous testosterone and low estradiol levels may cause a decrease in plasma HDL cholesterol, thereby being linked with atherosclerosis in middle aged men.

Increased carotid artery plaque score is an independent predictor of the presence and severity of coronary artery disease

OBJECTIVES Carotid ultrasonography is noninvasive and effective for the assessment of atherosclerotic lesions. The relationship between carotid ultrasound findings and presence and severity of coronary artery disease (CAD) was examined in Japanese patients. METHODS AND RESULTS Subjects were 116 patients who underwent carotid ultrasonography and coronary angiography. In carotid ultrasonography, mean-intima-media thickness (IMT), common carotid artery max IMT, bifurcation max IMT, plaque number, and plaque score (PS). The coronary angiographic data was obtained in the same period as carotid ultrasonography was performed. Patients were divided into two groups based on the presence or absence of coronary artery stenosis (CAS and non-CAS) and CAS group was further categorized into three groups, 1 vessel disease (1VD), 2VD, and 3VD. Physical findings, biochemical data, and carotid ultrasonogram data between the groups were compared. Items showing a significant difference between CAS and non-CAS were age, gender (male), incidence of diabetes and dyslipidemia, fasting blood sugar (FBS), triglyceride, HDL-cholesterol (HDL-C), high-sensitivity C-reactive protein, and all carotid ultrasound findings. All of the above parameters also showed a significant difference between four different severity groups. Stepwise logistic regression analysis was performed to determine which factors predict the presence and/or severity of CAS. High PS showed the strongest predictive value for both and followed by low HDL-C and high FBS. The cut-off value of PS obtained by receiver operating characteristic curve for predicting the presence of CAS was 1.9. CONCLUSIONS Assessment of PS by carotid ultrasonography together with other risk factor assessment was clinically relevant to predict the presence and severity of CAS.

Successful catheter ablation of ventricular tachycardia originating from the idiopathic saccular apical left ventricular aneurysm

Left ventricular (LV) aneurysm has been recognized to frequently become a substrate of ventricular tachyarrhythmias. We report a case of a 66-year-old woman with symptomatic sustained monomorphic ventricular tachycardia (SMVT) originating from saccular apical LV aneurysm without definite underlying diseases. We performed catheter ablation using electroanatomical and conventional bipolar potential mapping. During SMVT, we found an area of fragmented potential -40 ms preceding the earliest wide QRS complex in the area of the apical LV aneurysm. Radiofrequency applications were delivered to this area. Since then, SMVT was no longer inducible by programmed electrical stimulation. The patient has remained free of VT recurrences during a subsequent 12-month follow-up period.

Prognostic factors for the long-term survival in patients with vasospastic angina--analysis of effects of patients' characteristics and therapeutic drugs.

OBJECTIVES A retrospective study was conducted to elucidate contributing factors on the outcome of patients with vasospastic angina. SUBJECTS AND METHODS Two hundred ninety-two patients with angina in whom coronary vasospasm was documented were followed up (mean 4.3+/-3.6 years) to determine the relationship between the occurrence of cardiovascular events with available clinical factors including therapeutic drugs. Cardiovascular events were defined as fatal and non-fatal cardiovascular disorder events. RESULTS Several clinical variables including age, elevated creatinine level, low high-density lipoprotein (HDL) cholesterol level, presence of severe coronary artery stenosis, low left ventricular ejection fraction, low cardiac index (CI), large left ventricular mass, and use of beta-blockers proved to be significant risk factors for cardiovascular events. Further analysis by a stepwise regression analysis revealed that, older age (hazard ratio (HR)=1.42), low HDL cholesterol level (HR=0.877), presence of severe coronary artery stenosis (HR=49.32), and decreased CI (HR=14.18) proved to be independent prognostic factors. Ca antagonists were prescribed to 261 patients (89.4%). Among four Ca antagonists, there were significant differences in the frequency of cardiovascular events (2.6% with benidipine, 4.2% with nifedipine, 6.0% with diltiazem, 23.1% with amlodipine; amlodipine vs. benidipine, P<0.05) although the background characteristics of the four different patient groups were non-equivalent. CONCLUSION These results indicate that the morbidity of patients with vasospastic angina increased with older age, lower CI or HDL cholesterol, and presence of severe coronary artery stenosis, and that treatment with benidipine appeared to reduce cardiovascular events in patients with vasospastic angina.

Atrial septal defect in apical hypertrophic cardiomyopathy associated with coronary spasm.

Apical hypertrophic cardiomyopathy (HCM) is a well-known myocardial disease, but the additional coexistence of an atrial septal defect (ASD) and coronary spasm is quite rare. We report here on a 62-year-old man suffering from congestive heart failure due to apical HCM complicated by coronary spasm and secundum-type ASD. The transthoracic, transesophageal echocardiography and cardiac catheterization were useful for diagnosing and evaluating of the patients status. A calcium channel blocker was given to prevent coronary spasm, and a surgical patch closure operation was successfully performed. Afterwards, his symptoms were alleviated.