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Koichi Taniguchi

Publications and source records attributed to Koichi Taniguchi.

62 records · Page 4Linked to original sources

Efficacy of carvedilol treatment on cardiac function and cardiac sympathetic nerve activity in patients with dilated cardiomyopathy: comparison with metoprolol therapy.

UNLABELLED: Carvedilol and metoprolol have been reported to be effective in the treatment of patients with chronic heart failure. However, to our knowledge, there have been no studies comparing the effects of the 2 drugs on cardiac function, including cardiac sympathetic nerve activity. METHODS: We compared 15 patients with dilated cardiomyopathy (DCM) who were receiving carvedilol (group A) with 15 patients with DCM who were receiving metoprolol (group B). Before and after 1 y of treatment, cardiac (123)I-metaiodobenzylguanidine ((123)I-MIBG) uptake was assessed using the total defect score (TDS) and the heart-to-mediastinum (H/M) activity ratio from the delayed images. The New York Heart Association (NYHA) class and echocardiographic left ventricular ejection fraction (LVEF) also were assessed. RESULTS: In both groups, the TDS decreased (in group A, from 25 +/- 14 to 16 +/- 14, P < 0.01; in group B, from 27 +/- 9 to 19 +/- 10, P < 0.01), the H/M increased (in group A, from 1.67 +/- 0.31 to 2.01 +/- 0.36, P < 0.01; in group B, from 1.68 +/- 0.21 to 1.93 +/- 0.32, P < 0.01), the LVEF increased (in group A, from 31% +/- 10% to 48% +/- 10%, P < 0.01; in group B, from 28% +/- 9% to 47% +/- 15%, P < 0.01), and the NYHA functional class improved (in group A, from 2.9 +/- 0.3 to 1.7 +/- 0.5, P < 0.01; in group B, from 2.8 +/- 0.6 to 1.7 +/- 0.6, P < 0.01). The change in LVEF was mildly correlated with the change in the TDS in group A (r = 0.41) as well as in group B (r = 0.53). In the patients with a favorable response in the TDS or H/M, the NYHA class improved more than in the patients without a favorable response (P < 0.05). CONCLUSION: Carvedilol treatment can improve cardiac function, symptoms, and cardiac sympathetic nerve activity in patients with DCM to a similar extent as metoprolol treatment. The improvement of cardiac function and symptoms is related to the improvement of cardiac sympathetic nerve activity.

3-Iodobenzylguanidine↗

Nicorandil infusion leads to good recovery from ischemia of left ventricular regional work in comparison with nitroglycerin.

Nicorandil is an antianginal drug that exerts both a conventional nitrate effect and an independent ATP-dependent potassium channel-opening effect. The present study examined the effects of nicorandil on left ventricular regional work (RW) during coronary angioplasty in 22 patients with angina pectoris who were scheduled for angioplasty to the left anterior descending artery. The patients were randomly assigned to receive either nitroglycerin (group NG, n=12, 0.5 microg x kg(-1) min(-1)) or nicorandil (group NR, n = 10, 1.5 microg x kg(-1) min(-1)). Inflation was performed for 60 s and the data were collected every 10 s. The RW was derived from the relation between mean wall stress and area strain. The RW of the interventricular septum decreased after balloon inflation and was at its minimum after the 60s inflation (group NR: 1.24 +/- 0.72mJ/cm3, group NG: 0.63 +/- 0.25mJ/cm3). After balloon deflation, the septal RW of both groups increased, and recovered to the baseline condition at about 30s. At 20 s after deflation, the septal RW in group NR (3.58 +/- 1.17 mJ/cm3) was significantly higher than that in group NG (2.25 +/- 0.59mJ/cm3) (p < 0.05). An intravenous infusion of nicorandil led to good recovery of RW from ischemia compared with that obtained with nitroglycerin.

Aged↗

Candesartan cilexetil improves left ventricular function, left ventricular hypertrophy, and endothelial function in patients with hypertensive heart disease.

Patients with hypertension often develop left ventricular (LV) hypertrophy and deterioration of the cardiac and endothelial functions. Recent clinical trials have shown the added benefits of angiotensin II receptor blockers in hypertensive patients. Twenty-nine patients with hypertensive heart disease (HHD) underwent echocardiography, radionuclide ventriculography and the measurement of endothelial function before and after administration of candesartan (8 mg/day). The subjects were divided into poorly controlled blood pressure (BP) (group P, n=6) and well controlled BP (group C, n=23). Endothelial function was evaluated from flow-dependent dilation, which was calculated as the percent change of the radial artery diameter during reactive hyperemia after upper arm occlusion, measured with a high-resolution ultrasound system. In group C, LV diastolic function and endothelial function were significantly (p<0.05) improved at 3 months after administration, LV systolic function and hypertrophy were significantly (p<0.05) improved after 6 months and these effects were maintained at 12 months. Even in group P, LV function, LV hypertrophy, endothelial function and brain natriuretic peptide were significantly (p<0.05) improved at 6 months after administration. In patients with HHD, candesartan improves LV systolic and diastolic function, LV hypertrophy and endothelial function within 6 months of administration, regardless of the control of BP.

Adult↗

Dobutamine gated blood pool scintigraphy predicts the improvement of cardiac sympathetic nerve activity, cardiac function, and symptoms after treatment in patients with dilated cardiomyopathy.

BACKGROUND: We evaluated whether dobutamine gated blood pool scintigraphy (DOB-GBP) can predict improvement in cardiac sympathetic nerve activity and cardiac function after beta-blocker therapy in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: Twenty-two patients with DCM underwent DOB-GBP to measure left ventricular ejection fraction (LVEF) at rest, and during 5, 10, and 15 microg/kg/min of dobutamine infusion before therapy. Examinations were performed before and after 1 year of therapy. The heart/mediastinum count (H/M) ratio and total defect score (TDS) were determined for 123I-meta-iodobenzylguanidine images from anterior planar image and single-photon emission CT images. LVEF and left ventricular end-diastolic dimension (LVDd) were determined by echocardiography. After 1 year of treatment, the echocardiographic LVEF improved > 5% in 11 patients (group A), but did not improve in the remaining 11 patients (group B). Before treatment, TDS, H/M, LVEF, and LVDd were similar in both groups. However, there was a greater increase in the LVEF during dobutamine infusion in group A than in group B (21 +/- 8% vs 9 +/- 3%, p < 0.001). If a critical value of 15% for the DeltaLVEF was used to predict the improvement in LVEF after treatment, the sensitivity was 91% and specificity was 82%. The TDS, H/M ratio, LVDd, and New York Heart Association functional class improved in group A to a greater extent than in group B. CONCLUSIONS: DOB-GBP can be used to predict improved cardiac sympathetic nerve activity, cardiac function, and symptoms after treatment in patients with DCM.

3-Iodobenzylguanidine↗

[Comparison of clinical and angiographic outcomes between S670 and NIR stents].

OBJECTIVES: This study evaluated the long-term outcomes of successfully implanted S670 and NIR stents. METHODS: Stents were successfully implanted in 143 patients (148 lesions) aged 65 +/- 9 years from January 1999 to April 2001. Sixty-eight lesions were treated with S670 stents and 80 with NIR stents. Quantitative coronary angiography was performed before, immediately after and 6 months after implantation. An angiographic classification of in-stent restenosis was developed according to the geographic distribution of intimal hyperplasia in reference to the implanted stent. Furthermore, the relationships between stent diameter and length and restenosis rate were estimated. RESULTS: Type B2/C lesions were significantly more common in patients with S 670 (77.3%) stents compared with NIR (43.6%). Stent length was longer and diameter was smaller in patients with S 670 stents compared with those with NIR stents. Acute-gain was similar in the two groups, but late-loss was significantly greater in patients with S 670 stents compared with those with NIR stents. Restenosis rate and target lesion revascularization rate were similar in the two groups. The diffuse type of restenosis lesion was frequently found in S 670 stents. The stent diameter, but not stent length, influenced the restenosis rate in S 670 stents. Both stent length and diameter influenced the restenosis rate in NIR stents. CONCLUSIONS: Late-loss was larger and in-stent restenosis of diffuse type was significantly greater in S 670 stents compared with NIR stents. However, stent length was significantly longer and type B2/C lesions were significantly greater in S 670 stents compared with NIR stents. There was no difference in restenosis rate and target lesion revascularization rate. In addition, restenosis rate was not influenced by stent length in S 670 stents, so S 670 stents may be useful for complex lesions.

Aged↗

[Clinical significance of exercise-induced ST segment depression in patients with lateral myocardial infarction involving the left circumflex artery: evaluation by exercise 99mTc-MIBI myocardial scintigraphy].

PURPOSE: The aim of this study is to clarify the causes of exercise-induced ST-segment depression in patients with broad lateral old myocardial infraction involving LCX (LCX-OMI) without ischemia on exercise scintigraphy. METHOD: Twenty one patients (M/F = 11/10, age = 62 +/- 19 years) with myocardial infraction involving LCX (LCX-MI), but without fill-in on exercise and rest MIBI quantitative gated SPECT (QGS), were selected. They were divided into two groups of Group ST(+) (n = 11, with significant ST depression (max -2.8 +/- 0.4 mm), Group ST(-) (n = 10) without ST depression. On 20 SPECT segments of both exercise and rest SPECT, we scored uptake score as DS (0 = normal to 3 = defect) and wall motion as WMS (0 = normal to -5 = dyskinesis) and summed DS (TDS) and WMS (TWMS) in LCX region, furthermore, calculated the difference of TWMS (delta TWMS [exercise-rest]), end diastolic volume (EDV) and ejection fraction (EF) during exercise were compared between the two groups. RESULT: Group ST(+) showed significantly (p < 0.01) lower EF (35.4 +/- 9.2% vs. 60.2 +/- 6.2%), larger EDV (146 +/- 53 ml vs. 93 +/- 15 ml), higher TDS (5 vs. 7 +/- 3), lower TWMS (-25 +/- 9 vs. -6 +/- 5), furthermore lower delta TWMS (-6.9 +/- 4.0 vs. -2.0 +/- 0.8) than Group ST(-). CONCLUSION: Exercise-induced significant ST depression in V2-4 without ischema in LCX-MI was observed in patients with broad LCX-MI, low EF, and was related to impaired wall motion in LCX region. ST depression in V2-4 was considered to appear as miller image of ST elevation at postero-inferior wall due to disturbed wall motion on exercise.

Adult↗

Efficacy of amiodarone treatment on cardiac symptom, function, and sympathetic nerve activity in patients with dilated cardiomyopathy: comparison with beta-blocker therapy.

BACKGROUND: Amiodarone, which is an antiarrhythmic drug used to treat life-threatening arrhythmias, is effective in patients with chronic heart failure. However, its effectiveness compared with beta-blockers has not yet been reported. METHODS AND RESULTS: In 30 patients (mean age, 57 +/- 13 years) with dilated cardiomyopathy, we compared 15 patients receiving amiodarone (group A) with 15 patients receiving metoprolol (group B). Before and after 1 year of treatment, cardiac iodine 123 metaiodobenzylguanidine uptake was assessed from the total defect score, heart-to-mediastinum activity ratio based on delayed images, and washout rate. New York Heart Association class and echocardiographic left ventricular ejection fraction were also assessed. In both groups the total defect score decreased (from 25 +/- 11 to 16 +/- 10 in group A, P <.01; from 26 +/- 10 to 18 +/- 11 in group B, P <.01), the heart-to-mediastinum activity ratio increased (from 1.63 +/- 0.16 to 1.81 +/- 0.29 in group A, P <.01; from 1.63 +/- 0.21 to 1.85 +/- 0.3 in group B, P <.01), and the washout rate decreased (from 51% +/- 12% to 38% +/- 14% in group A, P <.01; from 48% +/- 11% to 37% +/- 8% in group B, P <.01). Left ventricular ejection fraction increased (from 30% +/- 9% to 42% +/- 11% in group A, P <.01; from 26% +/- 7% to 46% +/- 16% in group B, P <.01) and New York Heart Association functional class improved (from 3.1 +/- 0.5 to 1.8 +/- 0.7 in group A, P <.01; from 2.9 +/- 0.5 to 1.7 +/- 0.6 in group B, P <.01). CONCLUSION: Amiodarone treatment can improve cardiac symptom, function, and sympathetic nerve activity, as evaluated by I-123 metaiodobenzylguanidine imaging in patients with dilated cardiomyopathy, which improves to a similar extent with beta-blocker treatment.

Adrenergic beta-Antagonists↗