Biomedical subjects

N Tarumi

Publications and source records attributed to N Tarumi.

At least 37 records · Page 2Linked to original sources

PubMed1991

Left ventricular dysfunction during dynamic exercise in noninsulin-dependent diabetic patients with retinopathy.

Systolic time intervals were obtained from 19 middle-aged noninsulin-dependent diabetic patients without clinically evident cardiovascular disease (8 patients had and 11 did not have retinopathy) and 14 normal subjects using ear densitography. All subjects had neither ischemic electrocardiographic response nor chest pain during maximal treadmill exercise. Although left ventricular ejection time (LVET) and preejection period (PEP) did not differ significantly at rest between the three groups, a prolongation of LVET with a nearly identical PEP response was observed during exercise in diabetic patients with retinopathy. These data indicate that the diabetic patients with retinopathy relied on the enhanced ventricular filling in maintaining stroke volume during exercise. Thus, retinopathy is associated with impaired left ventricular systolic function in noninsulin-dependent diabetic patients.

Diabetes Mellitus, Type 2↗

PubMed1991

Clinical significance of pericardial rub with regional ventricular dilatation.

To elucidate the clinical characteristics associated with regional ventricular dilatation in the early phase of myocardial infarction (MI), 228 patients with acute Q-wave anterior MI were studied. Forty-nine patients (21 percent) had echocardiographically demonstrated regional ventricular dilatation (an abnormal bulge in the left ventricular contour during both systole and diastole) on the third hospital day. Careful auscultation revealed that a pericardial rub was present in 49 patients (21 patients with and 28 patients without regional ventricular dilatation) during the first three days after hospital admission. Multivariate analysis was performed to determine the relative importance of pericardial rub with six other clinical variables related to regional ventricular dilatation. Pericardial rub and cardiac output were the significant factors related to the presence of regional ventricular dilatation. Thus, a pericardial rub, in concert with impaired left ventricular function, is a physical sign associated with regional ventricular dilatation, and anatomically transmural infarction is the possible factor explaining their association.

Aged↗

PubMed1991

Diastolic time in diabetes. Impairment of diastolic time during dynamic exercise in type 2 diabetes with retinopathy.

To evaluate the effect of microangiopathic complications and autonomic dysfunction on diastolic time (DT) during dynamic exercise, 19 patients with type 2 diabetes and ten normal subjects were studied using ear densitography. All subjects had neither an ischemic electrocardiographic response nor chest pain during maximal treadmill exercise. The DT and heart rate (HR) had an inverse nonlinear relation, and electromechanical systole (QS2) and HR had an inverse linear relation during exercise. When the exercise DT-HR and QS2-HR relations were compared, a significant lengthening of QS2, with a consequent shortening of DT, was observed in diabetic patients with retinopathy, compared to patients without retinopathy and normal subjects (p less than 0.005), while no significant differences were found between diabetic patients without retinopathy and normal subjects; however, there were no significant differences in the exercise DT-HR and QS2-HR relations among diabetic patients with and without autonomic dysfunction and normal subjects. A more prominent abbreviation in the diastolic perfusion time observed in patients with retinopathy would be meaningful because microangiopathy might already have limited subendocardial blood flow. Thus, patients with type 2 diabetes who have retinopathy have a potential risk of aggravation of left ventricular function through the deterioration of myocardial blood flow.

Autonomic Nervous System Diseases↗

PubMed1991

Doppler echocardiographic assessment of prosthetic aortic valve function. Findings in normal valves.

To determine the Doppler-derived aortic flow velocity profiles in relation to type of prosthetic valve and left ventricular function, 70 patients with normal functioning aortic prosthetic valves (group 1 = 44 patients with low-profile mechanical valves and group 2 = 26 patients with high-profile mechanical valves) were evaluated. Peak flow velocity and mean systolic gradient were inversely related to valve size (r = -0.72; r = -0.76) in group 1. On the other hand, aortic flow velocity profiles had significant correlations with left ventricular end-systolic dimension (r = 0.75; r = 0.76) and left ventricular fractional shortening (r = -0.69; r = -0.66) in group 2. Thus, aortic flow velocity profiles in the low-profile mechanical valve were affected by pressure gradient caused by the valve size, whereas the hydromechanical disadvantage of the high profile mechanical valve affected the left ventricular pump function and Doppler-derived flow velocity profiles.

Aortic Valve↗

PubMed1991

[Frequency of complications of mitral valve prolapse in the elderly].

To evaluate the difference in the frequency of complication of mitral valve prolapse (MVP) according to sex in subjects aged 60 years and older, 543 patients (218 men and 325 women) who were diagnosed as having MVP by echocardiography at the Lahey Clinic Medical Center were studied. Three hundred and fourty eight patients had no complication of MVP (male vs female = 129:219). Infective endocarditis occurred in 20 patients (male vs female = 13:7). Rupture of chordae tendineae occurred spontaneously in 29 patients (male vs female = 20:9) and were associated with infective endocarditis in 8 other patients (male vs female = 6:2). Eighteen patients required mitral valve surgery for severe mitral regurgitation. The frequencies of these complications were higher in males than those in females. Cerebral ischemic events were encountered in 54 patients. There was no significant difference in the frequency between male and female. In conclusion, MVP in elderly men might be at for cardiac complication.

Aged↗

PubMed1989

Oxygen delivery, oxygen consumption and hemoglobin-oxygen affinity in acute myocardial infarction.

The interrelations of oxygen delivery (DO2), oxygen consumption (VO2) and hemoglobin-oxygen affinity assessed by P50 were investigated in 43 patients with acute myocardial infarction. As DO2 declined due to low cardiac output, a significant decrease in VO2 (r = 0.75, p less than 0.001) and a significant increase in P50 (r = -0.74, p less than 0.001) were observed. In the DO2 range between 300 and 450 ml/min/m2, in which the DO2 of 32 survivors and 11 nonsurvivors overlapped, the P50 of nonsurvivors was significantly higher than that of survivors (31.5 +/- 1.6 vs 27.9 +/- 1.5 torr, p less than 0.001), but there were no significant differences in any other oxygen transport variable. As a result of differences in P50, VO2 in this range was significantly higher in nonsurvivors compared to survivors (169 +/- 17 vs 148 +/- 13 ml/min/m2, p less than 0.001). These data suggest that a normal or increased VO2 alone does not ensure survival in patients with acute myocardial infarction, and increased P50 leads to an increase in VO2. Nevertheless, the interpretation of an increased P50 in patients with acute myocardial infarction must be made with caution, even with adequate DO2 and VO2, because it may imply a precarious oxygen transport/requirement balance in peripheral tissue and, hence, a fatal outcome.

Aged↗

PubMed1989

Left ventricular regional function after acute anterior myocardial infarction in diabetic patients.

To elucidate the pathophysiological role of diabetes mellitus in determining the left ventricular regional function of the noninfarcted area, 55 patients with acute Q wave anterior myocardial infarction (MI) were studied. The regional ejection fraction of the noninfarcted area was obtained by radionuclide angiocardiography and was used to estimate the left ventricular regional function of the noninfarcted area. Multiple regression analysis was performed to determine the important variables contributing to the regional ejection fraction based on 10 clinical variables: age, sex, QRS score, diabetes mellitus, hypertension, smoking, postinfarction angina, body mass index, serum cholesterol, and coronary atherosclerosis. A high QRS score (P less than .001) and the association of diabetes mellitus (P less than .05) were the important factors contributing to regional left ventricular dysfunction. The regional ejection fraction and QRS score had an inverse linear relationship in the diabetic and nondiabetic groups, and the regional ejection fraction was significantly lower in diabetic patients at every QRS score (P less than .05). The association of hypertension, severity of coronary atherosclerosis, serum cholesterol level, age, and body mass index did not differ between diabetic and nondiabetic patients, which indicates that diabetes mellitus was not mediated through these atherogenic traits. Thus, diabetes mellitus is another discrete cause of regional left ventricular dysfunction of the noninfarcted area after acute MI.

Diabetes Mellitus, Type 2↗

PubMed1975