Yoshinori L. Doi
University of Massachusetts Medical School
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Featured researches published by Yoshinori L. Doi.
American Journal of Cardiology | 1984
David H. Spodick; Yoshinori L. Doi; Richard L. Bishop; Tetsuo Hashimoto
Within limits, systolic time intervals are reliable reflectors of cardiac status and responses to physiologic and pharmacologic challenges, with various functional correlates. That heart rate (HR) is an important determinant of the duration of systole is well accepted, owing to its effect on left ventricular ejection time (LVET). An independent rate effect on preejection period (PEP) is disputed. Some studies in pooled normal subjects at rest showed some degree of HR-PEP covariance, leading to widespread rate correction in practical use. However, although right atrial pacing showed the expected HR-LVET relation, it consistently failed to show an HR-PEP relation. Systolic time intervals were examined from echocardiograms of a deliberately heterogeneous group comprising 50 consecutively appearing persons with sinus rhythm. There was no HR-PEP covariance (r = 0.23; p = not significant). However, our subjects were otherwise comparable to those of other investigators, in that all other relations in these subjects were as expected from studies in both pooled and paced subjects: HR with LVET (r = -0.74; p less than 0.001), PEP/LVET with ejection fraction (r = -0.85; p less than 0.001), and PEP/LVET with velocity of circumferential fiber shortening (r = -0.65, p less than 0.001). Thus, HR correction of PEP is inappropriate. All other relations are substantiated in routinely encountered, unselected subjects.
American Journal of Cardiology | 1981
Tetsuro Sugiura; Yoshinori L. Doi; Bruce G. Haffty; Kathleen A. Moreau; Richard L. Bishop; Jang B. Singh; David H. Spodick
Among 738 consecutive patients with chest pain referred for exercise testing, only 17 men fulfilled strict criteria for this pilot study: (1) achievement of at least 90 percent of age-predicted maximal heart rate or electrocardiographic criteria for a positive test; (2) subsequent coronary angiography; (3) exclusion of prior heart disease; and (4) absence of medication. Measurements of systolic time intervals obtained with ear densitography during early exercise differentiated 10 patients with coronary artery disease (Group 1) from 17 men (7 patients plus 10 normal volunteers) with normal coronary arteries (Group 2). Despite nearly identical heart rate and blood pressure responses in both groups, men in Group 1 had a significantly greater reduction of preejection period (PEP) at 1 minute and 4 minutes as well as a greater decrease in PEP/LVET (left ventricular ejection time) ratio. Differences were most significant when expressed as percent change of PEP/LVET ratio from control value (p less than 0.001 at both 1 minute and 4 minutes). After 4 minutes, men in Group 1 had no further decrease in PEP/LVET ratio and in 8 of the 10 men PEP/LVET ratio then increased to peak exercise. By contrast, PEP/LVET ratio continued to decrease to peak exercise in men in Group 2. The early floor in PEP/LVET ratio in Group 1 represents limited functional reserve and the subsequent increase suggests functional deterioration. Thus, densitographic systolic time interval measurements during uninterrupted exercise in unmedicated subjects appear to improve the sensitivity and specificity of the conventional treadmill test.
Lupus | 2009
Tetsuro Sugiura; Yoshitaka Kumon; Hiromi Kataoka; Yoshihisa Matsumura; Hiroaki Takeuchi; Yoshinori L. Doi
To determine the frequency and clinical correlates of asymptomatic pericardial effusion (PE) in patients with systemic lupus erythematosus (SLE), echocardiography and electrocardiography were performed in 50 consecutive patients with SLE. Among 50 patients with SLE, 12 patients (24%) had PE and 17 patients (34%) had hypoalbuminaemia. Patients with PE had a significantly lower serum albumin (P < 0.001), higher incidence of proteinuria (P = 0.003), higher C-reactive protein (P = 0.036) and pulmonary artery systolic pressure (P = 0.011) and tended to have a higher incidence of PR-segment depression (P = 0.082) compared with those without PE. When four variables (PR-segment depression, C-reactive protein, serum albumin and pulmonary artery systolic pressure) were used in the multivariate analysis, serum albumin (P = 0.005, odds ratio = 0.016) and pulmonary artery systolic pressure (P = 0.010, odds ratio = 1.106) emerged as significant variables related to the occurrence of asymptomatic PE. Thus, an increase in hydrostatic pressure of the right heart cavities and a decrease in colloid osmotic pressure were important factors associated with the presence of asymptomatic PE in patients with SLE.
American Journal of Cardiology | 1985
Tetsuro Sugiura; Toshiji Iwasaka; Yoshinori L. Doi; Bruce G. Haffty; Mitsuo Inada; David H. Spodick
To assess the relation between heart rate and diastolic time (cardiac cycle minus electromechanical systole) during the recovery period from upright exercise, 12 normal volunteers were studied immediately after and 2 and 5 minutes after exercise in the upright position. Although heart rate was significantly lower at 5 minutes compared with 2 minutes after exercise (106 vs 116 beats/min), there was significant shortening of diastolic time (from 251 to 230 ms) and total diastole per minute (from 28,634 to 24,220 ms/min). The explanation of this phenomenon appears to be disproportionate lengthening of diastolic time at 2 minutes after exercise, which must represent physiologic response due to increased left ventricular filling as well as continuing adrenergic effects, which would be diminished at 5 minutes. This lengthening of diastolic time also would maintain decreased subendocardial blood flow caused by increased end-diastolic volume.
American Heart Journal | 1982
Yoshinori L. Doi; Tetsuro Sugiura; Richard L. Bishop; Delores Paladino; Kathleen A. Moreau; David H. Spodick
Fig. 6. a, View of the transected aorta (Ao) at its isthmus and left main pulmonary artery which is occluded by thrombus CT). Extensive calcific deposits are present in the wall of the pulmonary artery. Lig = ligamenturn arteriosum. b, Photomicrograph of a small pulmonary artery in the left lung with multiluminal channels presumably representing organized thrombus. Many such arteries were present. No plexiform lesions were present. (Movat stain; original magnification X18.)
Chest | 1981
Yoshinori L. Doi; Tetsuro Sugiura; David H. Spodick
American Heart Journal | 1984
Yoshinori L. Doi; David H. Spodick; Naohisa Hamashige; Yoshihiro Yonezawa; Tetsuro Sugiura; Richard L. Bishop
American Journal of Cardiology | 1982
David H. Spodick; Tetsuro Sugiura; Yoshinori L. Doi; Delores Paladino; Bruce G. Haffty
American Heart Journal | 1981
Tetsuro Sugiura; Yoshinori L. Doi; Richard L. Bishop; Bruce G. Haffty; David H. Spodick
American Heart Journal | 1981
Yoshinori L. Doi; Tetsuro Sugiura; Richard L. Bishop; David H. Spodick