Miyoshi Ohno

A practical microcomputer-based mapping system for body surface, precordium, and epicardium☆

Abstract A practical microcomputer-based mapping system is introduced for three different potential mapping applications: (1) an array of 48 AgAgCl electrodes for epicardial mapping, (2) a system of 64 AgAgCl dry electrode for precordial mapping, and (3) an 87-electrode configuration for general body surface potential mapping. The compact, mobile microcomputer system with multiplexing and sample-and-hold techniques makes it possible to construct high-resolution maps from simultaneously sampled ECG potential data in clinical and experimental conditions. It takes only 20–25 min from the beginning of electrode placement to the completion of potential or isochronic map displays on the graphic terminal. Digital magnetic cassette tapes are used as external storage mediums which permit interchange of stored data on a larger computer.

Comparison Between Valsartan and Amlodipine Regarding Cardiovascular Morbidity and Mortality in Hypertensive Patients With Glucose Intolerance: NAGOYA HEART Study

It has not been fully examined whether angiotensin II receptor blocker is superior to calcium channel blocker to reduce cardiovascular events in hypertensive patients with glucose intolerance. A prospective, open-labeled, randomized, controlled trial was conducted for Japanese hypertensive patients with type 2 diabetes mellitus or impaired glucose tolerance. A total of 1150 patients (women: 34%; mean age: 63 years; diabetes mellitus: 82%) were randomly assigned to receive either valsartan- or amlodipine-based antihypertensive treatment. Primary outcome was a composite of acute myocardial infarction, stroke, coronary revascularization, admission attributed to heart failure, or sudden cardiac death. Blood pressure was 145/82 and 144/81 mm Hg, and glycosylated hemoglobin was 7.0% and 6.9% at baseline in the valsartan group and the amlodipine group, respectively. Both of them were equally controlled between the 2 groups during the study. The median follow-up period was 3.2 years, and primary outcome had occurred in 54 patients in the valsartan group and 56 in the amlodipine group (hazard ratio: 0.97 [95% CI: 0.66–1.40]; P=0.85). Patients in the valsartan group had a significantly lower incidence of heart failure than in the amlodipine group (hazard ratio: 0.20 [95% CI: 0.06–0.69]; P=0.01). Other components and all-cause mortality were not significantly different between the 2 groups. Composite cardiovascular outcomes were comparable between the valsartan- and amlodipine-based treatments in Japanese hypertensive patients with glucose intolerance. Admission because of heart failure was significantly less in the valsartan group.

Risk stratification and survival in post myocardial infarction patients: a large prospective and multicenter study in Japan

BACKGROUND Recent clinical trials suggest that the mortality in high-risk patients with ischemic heart disease can be significantly reduced with the use of implantable cardioverter-defibrillator (ICD). Given the high cost and invasiveness of the procedure, it is important to apply it to the patients after myocardial infarction (MI) highly susceptible to sudden arrhythmic death. OBJECTIVE The purpose of this study was to assess clinical predictors of mortality in post-MI patients in Japan. METHODS AND RESULTS In 495 consecutive MI survivors, 350 (71%) received acute-reperfusion therapy, whereas 145 (29%) did not. Nonsustained ventricular tachycardia (NSVT) was present in 136 patients (28%) in 24-h ambulatory ECGs at 7+/-6 in-hospital days. Left ventricular dysfunction (LVEF< or =35%) was present in 20/347 patients (5.7%) at 13+/-8 days. Forty-eight patients (9.7%) died during the follow-up period (48+/-13 months); 23 from cardiac and 25 from noncardiac causes. Kaplan-Meier survival analyses showed that mortality rates were higher among patients who were > or =70 years old (log-rank test, P<0.0001); had heart failure at admission (Killip scale> or =2, P=0.001); did not receive acute-reperfusion (P=0.004); and had left ventricular dysfunction with LVEF< or =35% (P=0.02). The presence of NSVT was a significant predictor of death (P=0.036) only in the patients who did not receive acute-reperfusion. Multivariate Cox regression analysis revealed that an independent predictor of total mortality was an age> or =70 (odds ratio, 1.06; 95% confidence interval, 1.01-1.11; P<0.00001). CONCLUSIONS High-risk patients after acute MI can be identified on the basis of age, ventricular dysfunction, heart failure and acute-reperfusion therapy. The presence of NSVT before discharge has a prognostic value only in the patients without acute-reperfusion.

Effects of coagulation Factor VII polymorphisms on the coronary artery disease in Japanese: Factor VII polymorphism and coronary disease

We investigated the relationships among Factor VII coagulant activity (FVIIc), genetic polymorphisms of Factor VII (FVII) and coronary artery disease (CAD) in 380 unrelated Japanese individuals (mean 64 years) who underwent coronary angiography and whose cholesterol levels were within normal range. CAD subjects were defined as those in whom one of the three major coronary arteries showed >50% narrowing after nitroglycerin administration. FVIIc was measured and the following polymorphisms of FVII were determined: R353Q polymorphism (M1, M2 alleles), -323 0/10 bp polymorphism (0, 10 alleles), hypervariable region 4 of intron 7 (HVR4; H5, H6, H7 alleles). FVIIc was slightly lower in M1M2/M2M2 than M1M1 (89.5+/-8.9%, 93.4+/-17.8%). Those with M2 and/or 10 allele have less chance of developing CAD (M2: OR 0.36, 95% CI 0.18-0.69, 10: OR 0.50, 95% CI 0.26-0.97). However, both alleles did not associate with myocardial infarction (MI). HVR4 was unrelated with CAD, nor with MI. In conclusion, M2 and/or 10 allele has protective effects on the developing CAD in individuals with a normal cholesterol level.

New two-dimensional, echocardiographically directed pericardiocentesis in cardiac tamponade

Seventeen patients with cardiac tamponade were treated by pericardiocentesis guided by two-dimensional (2-D) echocardiography and a needle guide. The needle guide used in the present study was designed so that the needle path lies within the center of the scan thickness. Before actual puncture, the mask method was performed in a water bath so that the needle progress avoided injury. The needle progress was monitored continuously in real time on the display throughout the procedure. Immediate relief from acute cardiac tamponade was obtained in all except one patient, who was treated by pericardiotomy because of insufficient drainage. In two patients, second drainage was performed because of reaccumulation of the pericardial effusion. There were no major complications. Nine patients recovered and the other patients died of underlying disease. Accurate and efficient visualization of the needle might allow a safer procedure. We conclude that pericardiocentesis guided by 2-D echocardiography using a needle guide may be a safe and easily applied technique for the management of pericardial effusion.

Body surface potential distributions in posterior ventricular pre-excitation***

Waveform of the QRS complex during ventricular pre-excitation is subject to the influence of both the site of pre-excitation and the time of pre-excitation relative to that of excitation via the normal AV path. This paper reports a case in which lead V1 of the electrocardiogram (ECG) could be altered from an R to an rS pattern by the administration of atropine sulfate. The provable mechanism was that of reduced conduction time in the normal AV path with altered time phase of normal excitation and pre-excitation. This mechanism was simulated in experiments on dogs and yielded similar findings. Body surface mapping in both the patient and the dogs provided evidence that pre-excitation could be recognized by that means with varied time phase of normal excitation and pre-excitation. It was demonstrated that the QRS complex of right sided precordial leads could be altered from an R to an rS pattern by altering the time phase of normal excitation and pre-excitation of the posterior ventricular wall. This alteration was related to the degree to which negative potentials on the anterior chest wall due to right ventricular breakthrough of normal activation developed in relation to the time of pre-excitation.

The number and function of circulating CD34+CD133+ progenitor cells decreased in stable coronary artery disease but not in acute myocardial infarction

Objective Circulating CD34+CD133+ cells are one of the main sources of circulating endothelial progenitor cells (EPCs). Age is inversely related to the number and function of CD34+CD133+ progenitor cells in stable coronary artery disease (CAD), but the relationship remains unclear in acute myocardial infarction (AMI). The authors aimed to clarify how ageing affects the number and function of mobilised CD34+CD133+ progenitor cells in AMI. Design and results Circulating CD34+CD133+ progenitor cells were measured by flow cytometry. Measurements were made at admission for CAD, or on day 7 after the onset of AMI. In stable CAD (n=131), circulating CD34+CD133+ cells decreased with age (r=−0.344, p<0.0001). In AMI, circulating CD34+CD133+ cells did not correlate with age (n=50), and multivariate analysis revealed that the decreased number of circulating CD34+CD133+ cells was associated with male sex and higher peak creatinine kinase. The ability to give rise to functional EPCs, which show good migratory and tube-forming capabilities, deteriorated among stable CAD subjects (n=10) compared with AMI subjects (N=6). Conclusions In stable CAD, the number and function of circulating CD34+CD133+ progenitor cells decreased with age, whereas those mobilised and circulating in AMI did not.

Risk factors for sudden unexpected death among workers: a nested case-control study in central Japan.

UNLABELLED BACKGROUND; Few studies have focused on sudden death among apparently healthy workers, and the risk factors have not been fully discussed. METHODS A nested case-control study was conducted among 164,017 male employees receiving annual medical checkups in Japan. Most recent medical checkup data of 242 sudden death victims (mean age, 48.0 years) were compared with corresponding data of 505 age-, workplace-, and job-type-matched male controls. Odds ratios (ORs) and their 95% confidence intervals (CIs) for each variable were calculated by logistic regression. RESULTS OR (95% CI) significantly increased with advancing blood pressure, reaching 6.6 (3.4-13.1) for systolic blood pressure > or =160 mm Hg relative to that <120 mm Hg. Hypo-HDL-cholesterolemia, hyperuricemia, increased aminotransferases, and abnormal urinary findings were associated with the risk in a dose-dependent manner. The presence of arrhythmias and ST-T abnormalities as well as abnormal Q waves on electrocardiograms yielded a 3.5 to 4.8 times greater risk of sudden death. As for lifestyles, heavy smoking was a positive, and light drinking was a negative risk factor. Multivariate analysis revealed that hypertension, proteinuria, glucosuria, arrhythmias, ST-T abnormalities, and light drinking were independent predictors for sudden death. CONCLUSION These findings suggest that periodic medical checkups can help to predict and prevent employee sudden death.

Myocardial SPECT and left ventricular performance study using a single Tc-99m teboroxime injection : comparison with thallium-201 myocardial SPECT

Myocardial SPECT using teboroxime was compared to thallium SPECT in 26 patients undergoing cardiac catheterization. Agreement between thallium SPECT and teboroxime SPECT for the identification of myocardial segments was 209/235 (89%). A significant correlation was found in 15 patients between the left ventricular ejection fraction by teboroxime first-pass study and the ejection fraction by contrast ventriculography. In nine patients with myocardial infarction and/or multivessel coronary artery disease, the ejection fraction revealed a mean decrease from 0.52 at rest to 0.46 at exercise. Teboroxime makes it possible to perform an exercise first-pass study of left ventricular ejection fraction followed by myocardial perfusion imaging.

Comparison of thallium-201 and technetium-99m teboroxime myocardial single photon emission tomography with coronary arteriography.

Myocardial single photon emission tomography (SPET) using technetium-99m teboroxime (teboroxime) was studied and the results compared with those of thallium-201(thallium) SPET and coronary arteriography in 19 patients. Resting teboroxime SPET was performed initially. Two hours later, exercise teboroxime SPET was performed. Exercise ergometer tests for both teboroxime and thallium were carried out in a supine position. The levels of exercise achieved for both tests were similar. Agreement for the identification of myocardial segments between thallium SPET and teboroxime SPET was 147/171(86%) (NS). When a significant stenosis was defined as ≥ 75% or ≥ 50%, agreement between two radiopharmaceuticals for the detection of diseased vessels was 89% (NS, κ = 0.601) or 88% (NS, κ = 0.713), respectively. In only 2/19 cases were inferior and posterior segments (3/171) difficult to interpret in teboroxime SPET due to hepatic activity. Thus, teboroxime SPET with a short data acquisition time resulted in a rapid completion for each study and had a good correlation with thallium SPET.