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Kiyoshi Yoshida

Publications and source records attributed to Kiyoshi Yoshida.

47 records · Page 3Linked to original sources
PubMed2003

Decreased left atrial appendage flow velocity with atrial fibrillation caused by negative inotropic agents: report of two cases.

Although pharmacological agents are frequently used to control ventricular rate or restore sinus rhythm of patients with atrial fibrillation (AF), there are no reports of the relationship between those agents and left atrial appendage (LAA) function. Two cases of a decrease in LAA blood flow velocity caused by negative inotropic agents are presented as an indication that negative inotropic agents are a risk factor for systemic thromboembolism with AF.

Atenolol↗
PubMed2003

Current characteristics of infective endocarditis in Japan: an analysis of 848 cases in 2000 and 2001.

The Japanese Circulation Society appointed a committee to develop guidelines for the prevention, diagnosis and management of infective endocarditis in Japan. In making such guidelines, the committee required information on the current clinical characteristics of infective endocarditis and therefore performed a nationwide questionnaire survey of cases from 2000 and 2001. In total, data were received for 848 cases from 277 of the 817 hospitals surveyed. Mean age was 55+/-18 years and most patients were aged in their 50 s or 60 s; 53.9% of the patients had infective endocarditis of unknown origin (without any prior predisposing conditions or procedures) and the second most common etiology was post dental procedures. The most common microorganism was Gram-positive cocci (345 streptococci and 221 staphylococci) and methicillin resistant Staphylococcus aureus (MRSA) was found in 7.3%. Although more than 90% of cases with Streptococcus viridans were sensitive to penicillin G, 6.6% were resistant. All MRSAs were sensitive to vancomycin. The information obtained from the survey assisted in the making of the guidelines, which should become an indispensable tool for all clinicians.

Adult↗
PubMed2002

Long-term prognosis of patients with type a aortic intramural hematoma.

BACKGROUND: Recent studies have shown an favorable short-term prognosis of patients with type A acute aortic intramural hematoma (IMH). The difference of aortic pathology may have a different impact on clinical course compared with classic aortic dissection (AD). The purpose of this study was to elucidate clinical features and long-term prognosis of patients with type A IMH. METHODS AND RESULTS: Clinical data were compared retrospectively between 30 patients with acute type A IMH (IMH group) and 101 patients with acute type A AD (AD group) who were admitted to our institutions from 1988 to 1998. In AD group, 72 patients underwent surgical repair and 29 patients were treated medically. All patients in IMH group were treated initially with supportive medical therapy. Thirteen patients who demonstrated progression to AD or increase in size of hematoma underwent timed surgical repair except for 1 patient. The overall in-hospital mortality rate in IMH group was significantly lower than that in AD group (7% and 34%, P=0.004). Follow-up periods were 56+/-37 (IMH group) and 60+/-42 months (AD group), which revealed 1 and 6 late deaths, respectively. The actuarial survival rates in IMH group were all 90% at 1, 2, and 5 years, which were significantly higher than those in AD group (67%, 66%, and 62%, respectively; P=0.004). CONCLUSIONS: Patients with type A IMH have better long-term prognosis than patients with AD.

Aged↗
PubMed2002

An alternative approach using long elephant trunk for extensive aortic aneurysm: elephant trunk anastomosis at the base of the innominate artery.

BACKGROUND: Although a staged elephant trunk procedure has been widely used, the early mortality of the first stage operation as well as the interval mortality between operations remains unsatisfactory. We developed an alternative elephant trunk procedure to reduce mortality and morbidity. METHODS AND RESULTS: Ascending aorta and arch vessels were minimally dissected. During systemic cooling, a four-branched arch graft with a sewing "collar" and a long "elephant trunk" was prepared. The ascending aorta was opened under selective brain perfusion with moderate hypothermia (25 degrees C), and the elephant trunk was then pulled down into the descending aorta using the catching catheter introduced via a femoral artery. The elephant trunk anastomosis using the collar was made at the base of the innominate artery. The arch vessels were divided and closed at aortic stump, and grafted separately as a consequence of the very proximal site for the elephant trunk anastomosis. Between October 1998 and September 2001, 17 patients, ranging in age from 25 to 79 years (mean 67 years) with extensive aortic aneurysm underwent this operation. Preoperative cardiac complications included coronary artery disease in 5, aortic regurgitation in 3, and 3 of these 8 patients had poor left ventricular function with an ejection fraction less than 40%. Nine patients underwent a second stage operation, in 1 of them the permanent elephant trunk procedure was initially attempted but the second stage procedure was done because of increasing endo-leakage. The mean interval between operations was 8 days (range 1 to 14 days) in the remaining 8 patients. In 5 of 6 patients who underwent the permanent elephant trunk procedure, a decrease in the size of the aneurysm based on thromboexclusion was observed using serial computed tomography scans. A single stage repair was performed in 1 patient. The 30-day survival rate of all operations was 100%, however, there was 1 in-hospital death (6%) after the second operation. There was no stroke, however, paraplegia occurred after the first operation in 1 patient (6%) of the in-hospital death. No new phrenic or recurrent laryngeal nerve palsy occurred as a result of surgery. CONCLUSIONS: The present technique using a modification of the elephant trunk technique for extensive aortic aneurysm provides acceptable mortality and morbidity. The present strategy would be an alternative for the standard elephant trunk procedure in some high-risk patients with advanced age and comorbidities.

Adult↗
PubMed2002

Effects of microvascular dysfunction on myocardial fractional flow reserve after percutaneous coronary intervention in patients with acute myocardial infarction.

Fractional flow reserve (FFR) has emerged as a lesion-specific index of the functional severity of coronary stenosis in patients with chronic coronary artery disease. As the coronary blood flow in acute myocardial infarction (AMI) patients with microvascular damage is restricted, the pressure drop across the stenosis during hyperemia may be smaller than expected. However, the effects of microvascular dysfunction on FFR in AMI patients remain undetermined. The study comprised 33 AMI patients who underwent coronary stenting within 12 hr of onset, and 15 patients with stable angina pectoris who underwent elective stenting. Assessment of the 48 lesions by means of intravascular ultrasound and pressure measurements after stenting showed that postinterventional FFR was higher in AMI than angina pectoris patients (0.95 +/- 0.04 vs. 0.90 +/- 0.04; P = 0.002), although there were no significant differences in intravascular ultrasound parameters. AMI patients were divided into two subgroups based on their postprocedural Thrombolysis on Myocardial Infarction (TIMI) flow grade (23 patients with TIMI 3 and 10 with TIMI 2). There were no differences in intravascular ultrasound parameters between the AMI subgroups, while FFR was greater in the patients with TIMI 2 than in those with TIMI 3 (0.98 +/- 0.02 vs. 0.93 +/- 0.05; P = 0.017). No significant correlation was found between FFR and intravascular ultrasound parameters in either AMI subgroup, while FFR of more than 0.94 was observed in all TIMI 2 cases independent of residual stenosis severity. We conclude that in patients with marked microvascular dysfunction, FFR may not be reliable for the assessment of coronary lesion severity and may underestimate coronary lesion severity.

Aged↗
PubMed2002

Noninvasive assessment of great cardiac vein flow by Doppler echocardiography: a validation study.

The objectives of this study were (1) to compare great cardiac vein (GCV) flow velocity detected by pulsed Doppler echocardiography (PDE) with Doppler guide wire (DGW) in the experimental setting and (2) to clarify whether transthoracic Doppler echocardiography (TTDE) can detect GCV flow in humans. Using opened-chest dogs, we detected GCV flow by PDE under the guidance of color flow Doppler mapping. GCV flow velocity was recorded by PDE and DGW, simultaneously. In 23 volunteers, GCV flow velocity was measured by TTDE. In the experimental setting, the prominent systolic flow wave of the GCV was obtained in PDE and DGW. There were good agreements between PDE and DGW for the measurements of GCV flow velocity (peak velocity: r = 0.98, y = 1.12chi-5.9; time velocity integral: r = 0.97, y = 1.10chi-0.71). In the human subjects, clear envelopes of GCV flow velocity were obtained in 21 (91%) of 23 subjects with the use of TTDE.

Adult↗
PubMed2002

[Measurement of coronary flow reserve by pressure/temperature sensor guide wire-based thermodilution in experimental models].

OBJECTIVES: Recently, a combined 0.014 pressure/temperature sensor-mounted guide wire has been developed to simultaneously measure fractional flow reserve and coronary flow reserve (CFR) by thermodilution (CFR-thermo). The accuracy of CFR-thermo was compared with CFR obtained by flow rate (CFR-flow) in experimental models. METHODS: Using an experimental model made from a straight-rigid tube (4 mm diameter) filled with 36 degrees C water, CFR-thermo and CFR-flow were measured under different conditions of sensor position and injected water temperature (0-40 degrees C). A side branch (2 mm diameter) was then placed at 4, 6, 8 and 10 cm from the injected site just proximal to the stenosis. The degree of stenosis ranged from 0 to 75% (0%, 25%, 50%, 75%). CFR-thermo and CFR-flow were calculated from the inverse ratio of the mean transit time and the flow ratio during high flow to low flow rates. RESULTS: Under the conditions without the side branch, there were good correlations between CFR-thermo and CFR-flow if the temperature of the injected water was under 28 degrees C and the sensor was not placed within 4 cm from the injection site. With the side branch, CFR-thermo was smaller than CFR-flow although there were good correlations between CFR-thermo and CFR-flow. The value of CFR-thermo increased with more distal positions of the side branch to the injected site. CONCLUSIONS: Temperature of the injected water, and the position of the sensor, the side branch and the stenotic lesion may influence measurements of CFR-thermo. These effects should be considered when CFR is measured by the thermodilution method.

Blood Flow Velocity↗
PubMedDate not supplied

Impact of insulin resistance on neointimal tissue proliferation after coronary stent implantation. Intravascular ultrasound studies.

Serial intravascular ultrasound (IVUS) studies in 55 nondiabetic patients showed that neointimal tissue proliferation after stent implantation in patients with impaired glucose tolerance (IGT) was greater than that in patients with normal glucose tolerance at follow-up. Multiple regression analysis showed that the sum of insulin levels was the best predictor of the greater neointimal index at follow-up. Another group of serial IVUS studies were performed in 62 stented lesions in 52 patients with Type 2 diabetes mellitus (DM). The study patients were randomized into a troglitazone group and a control group. The neointimal tissue proliferation at follow-up in the troglitazone group was significantly smaller than that in the control group.

Blood Glucose↗
PubMedDate not supplied

Usefulness of continuous air tonometry for evaluation of splanchnic perfusion during cardiopulmonary bypass.

Although gastric mucosal tonometry has been reported as a useful method to assess splanchnic perfusion during cardiovascular surgery, the conventional discontinuous method of tonometry (saline tonometry) was cumbersome and prone to systematic errors. A new automated system of air tonometry (Tonocap; Datex Ohmeda, Helsinki, Finland) allows for frequent (every 10 minutes) measurement of gastric regional CO2 (PrCO2) and may be more suitable as a monitoring system in cardiac patients. We evaluated the usefulness of continuous air tonometry as a marker of splanchnic perfusion during cardiopulmonary bypass (CPB). In 19 patients (53-79 years, mean 63 years) who underwent cardiovascular surgery under standard CPB with mild hypothermia (32 degrees C) from January 2001 to May 2002, the PrCO2 and calculated intramucosal pH (pHi) of gastric tonometry was monitored using Tonocap, and their relation to postoperative visceral organ function was evaluated. The pHi significantly increased after initiation of CPB from 7.32 +/- 0.07 to 7.43 +/- 0.10 (p < 0.05) and then consistently decreased in all patients to 7.39 +/- 0.09 at the end of CPB. The value of PrCO2 significantly (p < 0.01) correlated with the value of pHi. The lowest value of pHi during CPB was significantly related to blood urea nitrogen (r = -0.75, p < 0.05), serum creatinine (r = -0.78, p < 0.05), creatinine clearance (r = 0.68, p < 0.05) on postoperative day 1, and blood urea nitrogen (r = -0.84, p < 0.01) on day 3. In contrast, arterial blood lactate level, venous oxygen saturation, and routinely measured hemodynamics (e.g., pump flow, arterial pressure) during CPB were unrelated to the postoperative visceral organ function. These results suggest that continuous monitoring of gastric regional CO2 and pHi by air tonometry system is useful for the evaluation of splanchnic perfusion during CPB and may contribute to improve CPB technique by allowing the early detection of visceral malperfusion.

Aged↗