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Publications (7)13.25 Total impact

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    ABSTRACT: BACKGROUND: Mechanisms of the pseudonormalization (PN) of the transmitral flow (TMF) velocity pattern have been mainly attributed to left ventricular diastolic function. PURPOSE: To assess the influence of left atrial (LA) function on the PN with two-dimensional tissue tracking technique. METHODS: The subjects consisted of 21 healthy volunteers and 70 patients with various cardiac diseases. Images of one cardiac cycle in the apical four-chamber view were stored by the HIVISION 900 (Hitachi Medico, Chiba, Japan). The LA volume (LAV) loop was created using two-dimensional tissue tracking technique and LAV index (LAVI) at a given cardiac phase was calculated. A preload of 90mmHg was applied using a customized lower body positive pressure (LBPP) system. Patients were divided into the PN group (n=18) with their early diastolic TMF velocity (E) increased and late diastolic TMF velocity (A) decreased, and the non-(N)-PN group (n=52) with both E and A wave velocities increased by LBPP. RESULTS: (1) During LBPP, the LAVImax in both the groups increased significantly. (2) In the N-PN group, the LAVIpass (p<0.001), LAVIact (p<0.01), and LAVItotal (p<0.0001) increased significantly. The dV/dts (p<0.0001) and dV/dtE (p<0.0001) increased significantly with an increase in the dV/dtA. On the other hand, there was no change in those parameters except LAVIpass (p<0.05) and dV/dtE (p<0.05) significantly increased in the PN group. (3) As a result, the LAVImin was significantly greater in the PN group than in the N-PN group (p<0.0001) during LBPP. The ratio of E velocity to early diastolic mitral annular velocity (E/E') during LBPP was significantly greater in the PN group than in the N-PN group (p<0.0001). CONCLUSIONS: The lack of an increase in active LA emptying volume in response to an increase of preload leads to elevated LA pressure and the pseudonormalization of the TMF velocity pattern in patients with various cardiac diseases.
    Journal of Cardiology 03/2013; · 2.30 Impact Factor
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    ABSTRACT: Previous studies have shown highly effective lowering of blood pressure with thiazide diuretics in combination with angiotensin receptor blockers. However, thiazide diuretics may cause the development of diabetes and abnormal lipid metabolism. Little is known as to whether dysmetabolic potential of thiazide diuretics could be neutralized when adding angiotensin receptor blockers. This study consisted of 26 patients with essential hypertension. Patients were randomized to 24 weeks of treatment with either candesartan, 12 mg monotherapy (n = 13, group A), or hydrochlorothiazide (HCTZ), 6.25 mg in combination with candesartan, 8 mg (n = 13, group B). Before and after treatment, we assessed glucose and lipid profiles including adiponectin, resistin, and active glucagon-like peptide-1 (GLP-1) levels. At baseline, there were no differences in age, body mass index, systolic blood pressure (SBP), and diastolic blood pressure (DBP), as well as plasma levels of hemoglobin A1c, insulin, low-density lipoprotein cholesterol, triglycerides, adiponectin, resistin, and active GLP-1 between the two groups. There were significant reductions in SBP (from 152 ± 10 mmHg at baseline to 134 ± 12 mmHg after treatment) and DBP (from 84 ± 5 mmHg at baseline to 71 ± 8 mmHg after treatment) in group A. There were also significant reductions in SBP (from 148 ± 10 at baseline to 128 ± 7 mmHg after treatment) and DBP (from 90 ± 9 at baseline to 74 ± 12 mmHg after treatment) in group B. There were no differences in reduction of SBP or DBP after 24 weeks of treatment between the two groups. There were no changes of the glucose and lipid profiles, including adiponectin, resistin, insulin, and active GLP-1 levels after 24 weeks of treatment in both groups. A low dose of HCTZ in combination with candesartan reduces blood pressure effectively without adverse effects on the glucose and lipid profiles. Therefore, the combination of thiazide diuretics and angiotensin receptor blockers could assist patients in achieving long-term control of blood pressure with good tolerability.
    Heart and Vessels 03/2012; · 2.13 Impact Factor
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    ABSTRACT: The diagnostic accuracy of using electrocardiographic findings to identify affected vessels in cases of myocardial infarction and angina pectoris treated by percutaneous transluminal coronary angioplasty was assessed. From the anterior wall leads, ST segment elevation in leads I and aV(L) showed diagnostic accuracy (sensitivity, specificity and positive predictive value) in identifying proximal lesions of the left anterior descending coronary artery of 89%, 58% and 62%, and the diagnostic accuracy of the QS wave in V(1) was 62%, 83% and 72%, respectively. For the posterior wall leads, the corresponding values for the diagnosis of affected vessels based on R/S>1 in V(1) for the left circumflex coronary artery were 50%, 89% and 60%, respectively. The inferior wall leads with ST segment elevation in leads II, III and aV(F), and ST segment depression in aV(L), showed diagnostic accuracy for the right coronary artery of 90%, 90% and 92%, respectively. Bifurcation of the first diagonal branch, dominance of the posterior descending branch, the normal subtypes of the coronary artery and the occurrence of spontaneous recanalization may have influenced the accuracy of diagnosis. Adding a high lateral wall lead one intercostal space above V(4) and a posterior wall lead located one intercostal space below V(6) appeared to increase the diagnostic accuracy of detecting the coronary artery lesions responsible for myocardial ischemia.
    Circulation Journal 09/2003; 67(9):775-80. · 3.58 Impact Factor
  • European Journal of Heart Failure 06/2000; 2. · 5.25 Impact Factor
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    ABSTRACT: There has been no report on T wave alternans (TWA) in patients with cardiac sarcoidosis. In this study, we investigated TWA in patients with cardiac sarcoidosis. Electrocardiographic recording for TWA was performed in 6 patients, using the CH2000 (Cambridge Heart). TWA was defined as positive in cases where alternans voltage of >1.9 μV and alternans ratio of >3.0 persisted more than 1 minute during exercise with ergometer with heart rate above 105 beats/min. TWA was positive in 3 patients, negative in 2 patients, and not determined in 1 patient. Arrhythmia was noted on Holter electrocardiogram in all 3 patients with positive TWA: sustained ventricular tachycardia in 1 patient and nonsustained ventricular tachycardia in 2 patients. Mean left ventricular ejection fraction in the 3 patients with positive TWA was 39.0%, whereas in the 2 patients with negative TWA it was 58.5%. A close relationship was suggested between TWA and severity of cardiac sarcoidosis.
    Journal of Electrocardiology - J ELECTROCARDIOL. 01/1999; 32:205-205.
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    ABSTRACT: To determine whether the departure parameters derived from a "departure loop" of a vectorcardiogram are more accurate than conventional spatial parameters in evaluating myocardial infarct size, 74 patients with first-onset myocardial infarction (MI) were studied. The correlation between the departure parameters (amplitudes in scalar leads of the departure loop) and the percent defect volume of thallium myocardial scintigrams (%DV) was compared with that of the spatial parameters (magnitude, azimuth, and elevation of the original QRS loop). In anteroseptal MI, the amplitude of a 20-msec vector in the z-axis and the azimuth of a 30-msec vector (H30) were significantly correlated with %DV (r=0.783, p<0.001 and r=0.572, p<0.05). In anteroseptal MI with involvement of the lateral wall, the amplitude of a 30-msec vector in the x-axis and H30 showed significant correlation with %DV (r=0.802, p<0.001 and r=0.772, p<0.01). In inferior and inferoposterior MI, the amplitude of a 30-msec vector in the y-axis and the elevation of a 30-msec vector were significantly correlated with %DV (r=0.920, 0.891, p<0.001 and r=0.871, 0.678, p<0.01, respectively). In conclusion, the departure parameters are more accurate than the spatial parameters for evaluation of myocardial infarct size.
    Japanese Circulation Journal 07/1998; 62(7):473-8.
  • Japanese Circulation Journal-english Edition - JPN CIRC J. 01/1998; 62(7):473-478.