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Biomedical subjects

N Doba

Publications and source records attributed to N Doba.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Hypertrophic cardiomyopathy associated with anomalous origin of the left coronary artery from the right sinus of valsalva].

A 47 year old Japanese male with exertional shortness of breath, cardiac murmur and ECG abnormalities was examined with invasive and non-invasive cardiology techniques that disclosed hypertrophic cardiomyopathy, and the anomalous origin of the left coronary artery from the right sinus of Valsalva. Although both situations have been known to cause sudden death especially under a state of strenuous physical stress, his exercise thallium scintigraphy performed with the symptom limited maximal test did not uncover any significant myocardial ischemia or exercise induced malignant arrhythmias. This is a very rare association of two distinctly identified clinical situations highly indicative of a likelihood of sudden cardiac death. Therefore, careful observation is needed.

Cardiac Catheterization↗
PubMed1991

[Charcot-Marie-Tooth disease associated with dilated cardiomyopathy: an autopsy case report].

This is a clinical report of a rare case of Charcot-Marie-Tooth disease associated with dilated cardiomyopathy. A seventy-seven-year-old Japanese male first visited our outpatient clinic with a ten-year history of muscular weakness in his bilateral lower extremities and gait disturbance characterized by classical features of peroneal muscular atrophy and inverted champagne bottle legs. Biopsy findings of the m. quadriceps femoris and the n. gastrocnemius revealed clustered atrophy of myofibrils and segmental demyelinization mingled with remyelinization. Because of his other problem of dilated cardiomyopathy, he had been treated with salt restriction, digitalis, diuretics and vasodilators, until his third hospitalization, when he developed terminal stage of severe congestive heart failure. Despite our intensive cardiac care, the patient died because of profound pump failure. Autopsy findings disclosed a remarkably dilated left ventricular chamber and an increased total heart weight of 600 grams. Grossly, the cross sectional view of the left ventricle revealed diffuse, but not homogenous fibrosis that was most prominent in the posterior wall. On light microscopic examination, the left ventricular myocardium revealed diffusely scattered muscular degeneration interlaced with fibrosis. Although large epicardial coronary arteries revealed only mild intimal atheromatous thickening, most of the small intramuscular coronary arteries were free from atherosclerosis. Neither diabetic nor amyloid lesions could be detected. It has been well known that cardiomyopathy is often associated with various forms of muscular dystrophy and Friedreich's ataxia.(ABSTRACT TRUNCATED AT 250 WORDS)

Atrophy↗
PubMed1990

Physical training of the patients with coronary heart disease: noninvasive strategies for the evaluation of its effects on the oxygentransport system and myocardial ischemia.

To clarify the central effects of physical training on patients with coronary heart disease, 81 subjects were selected for the present study. Evaluations of the oxygen transport system function were performed according to the definition proposed by Bruce and others in terms of FAI (functional aerobic impairment), LVI (left ventricular impairment) or MRI (myocardial reserve impairment), CRI (chronotropic reserve impairment) and PCI (peripheral circulatory impairment). Remarkable improvement in left ventricular impairment was found in those patients with single vessel disease or those who experienced disappearance of chest pain after the completion of the program. In another series of study on myocardial perfusion performed on 11 patients with coronary heart disease, improvement in ischemia was also demonstrated in 7 of 8 patients who revealed redistribution pattern in 201TL exercise stress images specifying myocardial ischemia. In conclusion, exercise training could induce improvements not only the left ventricular functions characterized by increased maximal pressure rate product and maximal heart rate, but also in myocardial ischemia. Further studies are needed to specify its effects, since natural progression or regression of the disease process itself may influence the results.

Coronary Disease↗
PubMed1989

[Determination of the blood pressure level in mild hypertension. Significance of 20 minute resting blood pressure measurement comparing to 24 hour ambulatory blood pressure monitoring].

Determination of the blood pressure (BP) level in patients with mild hypertension (MHT) is quite difficult, since ulcerations of BP are tremendously exaggerated in the doctor's office. It has been well known that casual BP is less reliable to estimate LVH than BPs obtained at home or work-site. Although 24 hour ambulatory BP monitoring (ABPM) has been widely accepted to overcome this problems, it is still controversial whether this method is applicable to all hypertensive subjects with special regards to its cost and effect. Therefore, our study has dealt mainly with the development of more convenient and less expensive method to get reasonable BPs. Twenty two nonmedicated patients with MHT were selected for the study. After taking casual BP in the office, the resting 20 minute BP measurements at every 2 minute interval were performed with Dynamap 950. Ten BP values thus obtained were divided into two categorical phases; early and late. The mean systolic and diastolic pressures (Ps & Pd) in the early phase were significantly higher than those in the late phase. Beside mean Ps and Pd obtained from 24 hour ABPM, 4 categorical phases based on the time of a day were defined; morning (from awaking to noon), afternoon (from noon to 6 pm), evening (from 6 pm to bed time) and night (during sleeping). Mutual correlation coefficients of these categorical BPs were calculated and compared to identify reasonably high significant correlations. The results revealed the highest BP at the office and the lowest one during sleeping. The office BPs closely resembled to the ones during afternoon period.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Pacemaker catheter induced systolic murmurs in two patients].

Although extracardiac sounds secondary to cardiac pacing have been well known, the murmurs originating in the heart after permanent pacemaker implantation and then disappearance after exchanging a temporary to permanent lead have rarely been reported. In this paper, two patients revealing a musical systolic murmur after placement of a transvenous endocardial pacemaker in the absence of any complications were documented. Case 1: A 43-year-old man with episodes of dizziness and brady-tachycardiac atrial fibrillation. Immediately after the implantation of a temporary transvenous right ventricular pacemaker, a high-pitched systolic musical murmur was heard at the lower left sternal border. No murmur was however gullible after a permanent pacemaker implantation in this case. Case 2 was a 83-year-old female with coronary heart disease associated with sick sinus syndrome to whom a permanent transvenous right ventricular pacemaker was inserted. A musical systolic murmur occurring immediately after the procedure was best audible at the apex. Although numerous papers concerning the mechanisms of these cardiac murmurs have been reported without reaching conclusive explanations, our data based on two cases examined with Doppler echocardiography did not support the idea of tricuspid regurgitation as one of causative factors. In the first case, this murmur appeared only a temporary pacing was performed and disappeared after implantation of a permanent pacemaker lead. On the contrary, however, the 2nd case revealed after the implantation of the permanent pacemaker with a relatively rigid bipolar lead. It is concluded that these murmurs might be produced by vibrations caused by the pacing catheters and physical properties could be related the mechanism of this phenomenon.

Adult↗
PubMed1989

[Studies on evaluation of the oxygen transport system function with multistage treadmill stress testing: comparison between normal control subjects and patients with coronary heart disease].

The oxygen transport system (OTS) function was evaluated with multistage treadmill stress testing on 171 normal control subjects and 80 patients with coronary heart disease (CHD). After Bruce's definition, OTS function was expressed with functional aerobic impairment (FAI), left ventricular impairment (LVI) or myocardial aerobic impairment (MAI), heart rate impairment (HRI) or chronotropic reserve impairment (CRI) and peripheral circulatory impairment (PCI). All subjects were monitored on heart rate, blood pressure, electrocardiogram and endtidal O2 and CO2 before and every one minute during the symptom limited maximal stress testing. Seventy three of 80 coronary patients were subjected to the coronary arteriography and were classified into four groups; 31 with single vessel disease (SVD), 20 with double vessel disease (DVD), 15 with triple vessel disease (TVD) and 7 with A-C bypass surgery. Comparison between normal control subjects and the CHD patients with regard to the relation of age and VO2max derived from the linear regression analysis disclosed the identical age-related decrease in VO2max in both groups. The age corrected VO2max in the CHD patients, however, was 2.2 METS less than that of normal control subjects. Therefore, the level of VO2max in CHD patients was determined not only by disease, but also by ageing process itself. Comparisons among three CHD groups with regard to FAI, LVI, HRI and PCI clearly demonstrated different functional impairments paralleling to the severity of the disease process. On the other hand, the patients with A-C bypass surgery revealed almost identical functional impairment to the patients with SVD. In conclusion, these simple and noninvasive evaluations of the oxygen transport system could give us valuable informations reasonably differentiating the clinical status of the patients with CHD.

Adult↗
PubMed1988

Prediction of the progression of cardiac hypertrophy in middle-aged mild hypertensives.

To investigate the predictive value of exercise tests and diastolic function measurements for the progression of left ventricular hypertrophy, symptom-limited treadmill stress testing and echocardiography were performed before and after a follow-up period of 3.5 years in 47 mild hypertensive men aged 42 +/- 2 years. The men were classified into three groups by the progression of the left ventricular mass index (%LVMI) during the observation, i.e. (LVMI after follow-up) - (LVMI before follow-up)/(LVMI before follow-up). The high-progression group (n = 13) had a %LVMI exceeding mean +/- 2/3s.d. of all subjects; the low-progression group (n = 21) had a %LVMI within mean +/- 2/3s.d. and the non-progression group (n = 13) had a %LVMI less than mean -2/3s.d. At the beginning of the observation, age, blood pressure at rest, LVMI, ejection fraction, mean velocity of circumferential fibre shortening, peak shortening rate and systolic time intervals (ET/PEP, ratio of ejection time to pre-ejection period) were similar among the three groups. However, the high-progression group showed a higher systolic pressure at peak exercise, a lower peak filling rate and a longer time to peak filling rate (TPFR) as corrected by the R-R interval of the ECG. These data suggest that systolic pressure at peak exercise and echocardiographically assessed diastolic function are useful in predicting the progression of cardiac involvement in mild hypertension.

Adult↗
PubMed1983

Semi-supervised exercise training program for patients with coronary heart disease--its effectiveness and possible diagnostic implications for predicting their severity.

Semi-supervised physical training for 12 weeks was performed on 60 patients with coronary heart disease including 48 patients with myocardial infarction and 12 with angina pectoris. The training program consisted of medically-supervised training at the institute once a week and unsupervised training at home at least twice a week with an intensity of 70 to 85% of the maximum heart rate which had been attained by a symptom-limited multiphasic treadmill stress testing according to Bruce's protocol. The results showed an average increase of maximum oxygen consumption from 27.0 +/- 5.7 to 31.0 +/- 7.8 ml/min X kg (p less than 0.01) and of treadmill time from 507 +/- 120 to 673 +/- 140 sec (p less than 0.0001). Cardiovascular responses reduced at a submaximal level of exercise and remained unchanged at the maximal level of exercise. No detrimental events were encountered during the program. The left heart catheterization and coronary angiogram were performed on 35 out of 60 patients. The trainability was higher in patients with single-vessel disease than in those with multi-vessel disease. Based on these results, supervised training should be required mostly for patients with low physical fitness, and patients with high physical fitness can probably improve their physical abilities by self-training at home following a proper exercise program.

Adult↗