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Dive into the research topics where Yukio Kazatani is active.

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Featured researches published by Yukio Kazatani.


Hypertension | 1995

Blood Pressure Response to the Valsalva Maneuver in Pheochromocytoma and Pseudopheochromocytoma

Mareomi Hamada; Mikio Mukai; Yukio Kazatani; Tatsuo Kokubu; Kunio Hiwada

To elucidate whether a difference in blood pressure reactivity exists between patients with pheochromocytoma (n = 8) and pseudopheochromocytoma (n = 22), we evaluated blood pressure changes during a Valsalva maneuver and baroreceptor reflex sensitivity. We also examined the effects of propranolol and prazosin on blood pressure reactivity during a Valsalva maneuver in patients with pseudopheochromocytoma. Pseudopheochromocytoma was defined as a paroxysmal rise in blood pressure accompanying pheochromocytoma-like symptoms and normal catecholamine values. The difference in systolic blood pressure between phase IV of the Valsalva maneuver and baseline (delta SBP) was markedly smaller in the pheochromocytoma patients (8.4 +/- 18.4 mm Hg) than in the essential hypertension patients (n = 30, 30.9 +/- 19.4 mm Hg) and normotensive control subjects (n = 10, 31.3 +/- 11.4 mm Hg), whereas delta SBP in the pseudopheochromocytoma patients (77.8 +/- 11.2 mm Hg) was markedly greater than in the other three groups. delta SBP was markedly suppressed by the administration of both propranolol and prazosin. Baroreceptor reflex sensitivity index was lower in the pheochromocytoma group than in the other three groups. In conclusion, blood pressure reactivity responses to a Valsalva maneuver are disparate between pheochromocytoma and pseudopheochromocytoma. The high blood pressure reactivity to a Valsalva maneuver in pseudopheochromocytoma is due to hyperactivity in both beta- and alpha 1-adrenergic receptor functions, and the low blood pressure reactivity to a Valsalva maneuver in pheochromocytoma seems to be mainly due to the desensitization of both adrenergic systems associated with chronic catecholamine excess. In addition, the impaired baroreceptor function in pheochromocytoma is partially responsible for it.


Journal of Hypertension | 1987

Enhanced Blood Pressure Response to Isometric Handgrip Exercise in Patients with Essential Hypertension: Effects of Propranolol and Prazosin

Mareomi Hamada; Yukio Kazatani; Taketoshi Ito; Tatsuo Kokubu; Shozo Ishise

To elucidate whether a difference exists in blood pressure (BP) elevation during isometric handgrip exercise (IHG) between essential hypertensives (EHT) and normotensives (NT), IHG was carried out in 12 NT and 46 EHT under constant sodium intake using a new instrument. The acute effects of propranolol and prazosin on IHG were also examined in EHT. The change in systolic BP (delta SBP) during IHG in EHT, delta SBP = 61 +/- 21 mmHg, was markedly greater than that in NT, delta SBP = 28 +/- 4 mmHg. Among EHT, delta BP increased with increasing severity of hypertension. Neither the changes in plasma norepinephrine nor in epinephrine during IHG showed significant differences between EHT and NT. The pressor response during IHG could not be suppressed by propranolol, but about 30% suppression of BP was observed during IHG with prazosin. It is concluded from these findings that EHT have an exaggerated BP response to IHG that is due to increased post-junctional alpha 1-adrenoceptors.


Angiology | 1998

Clinical Characteristics in Japanese Patients with Coexistent Hypertrophic Cardiomyopathy and Coronary Vasospasm

Mareomi Hamada; Yukio Kazatani; Keisuke Matsuzaki; Eiki Murakami; Kunio Hiwada; Koji Kodama

There are only a few reports concerning coexistent hypertrophic cardiomyopathy (HCM) and vasospastic angina. Clinical characteristics in patients with both diseases have not been clarified yet. This study was designed to elucidate the relationship between chest pain and coronary vasospasm in HCM patients and to delineate clinical characteristics in patients with both HCM and coronary vasospasm. First, 36 patients with HCM underwent acetylcholine provocation test for coronary vasospasm and were divided into two groups on the basis of presence or absence of coronary vasospasm. Next, the following risk factors for coronary artery disease were compared between the two groups: hypertension, smoking, hyperlipidemia, diabetes mellitus, and hyperuricemia. Coronary vasospasm was induced in 10 (28%) of 36 patients with HCM. There were no significant differences in age and male gender between the two groups. Smoking was more prominent in HCM patients with than without coronary vasospasm (80% vs 35%, p<0.05), but there were no differences in the prevalence of other risk factors between the two groups. In conclusion, coronary vasospasm appears to play a significant role in the etiology of myocardial ischemia in Japanese patients with HCM, and smoking might be a major risk factor for coexistence of HCM and coronary vasospasm.


American Journal of Therapeutics | 1995

Beneficial Effect of a Long-Term Antihypertensive Therapy on Blood Pressure Response to Isometric Handgrip Exercise in Patients with Essential Hypertension.

Yukio Kazatani; Mareomi Hamada; Kunio Hiwada; Tatsuo Kokubu

To elucidate the effect of a long-term antihypertensive therapy on blood pressure (BP) response to isometric handgrip exercise (IHG) in patients with essential hypertension (EHT, n = 16), IHG was carried out at 30% maximal voluntary contraction of right hand for 3 min before therapy and after a long-term antihypertensive therapy. BP responsiveness to IHG was estimated by the difference between values obtained at rest and at 3 min during IHG (change of systolic BP = δSBP, change of diastolic BP = δDBP).Both δSBP and δDBP before therapy were markedly greater in EHT (δ SBP = 64 ± 18 mm Hg, δDBP = 33 ± 9 mm Hg) than in age-matched normotensive controls (NT, n = 8, 29 ± 4 mm Hg, 18 ± 4 mm Hg). By antihypertensive therapy, SBP and DBP in EHT were decreased from 152 ± 22 mm Hg to 136 ± 14 mm Hg and from 90 ± 18 mm Hg to 83 ± 10 mm Hg, respectively, but both SBP and DBP in EHT after antihypertensive therapy were still greater than those in NT. Both δSBP and δDBP in EHT after a long-term antihypertensive therapy were significantly smaller than those in EHT before therapy but were still significantly larger than those in NT. These results demonstrate that a long-term antihypertensive therapy reduces the exaggerated BP response to IHG in EHT.


Angiology | 2006

Systemic versus coronary levels of inflammation in acute coronary syndromes.

Makoto Suzuki; Makoto Saito; Takayuki Nagai; Hideyuki Saeki; Yukio Kazatani

To address a possible link between systemic and coronary inflammation in the setting of acute coronary syndromes, the authors examined both levels of 3 inflammatory mediators such as high sensitive C-reactive protein (hs-CRP), interleukin (IL)-6, and matrix metalloproteinase (MMP)-9 in patients with the early phase of acute myocardial infarction (AMI). In total, 20 patients with AMI showing minimal elevation of cardiac enzymes were studied. Before angioplasty, peripheral blood and culprit coronary thrombus were sampled to compare systemic and coronary levels of hs-CRP, IL-6, and MMP-9. Relation of systemic levels of hs-CRP and IL-6 to culprit coronary morphology was also evaluated by the use of intravascular ultrasound. Systemic and coronary levels of hs-CRP were nearly equivalent (4.3 ±5.0 vs 4.7 ±5.4 mg/L, p=0.279), whereas IL-6 and MMP-9 showed higher in coronary levels than in systemic levels (169 ±154 vs 93 ±107 pg/mL, p=0.002 and 164 ±116 vs 103 ±94 ng/mL, p=0.018, respectively). Systemic levels of hs-CRP were correlated with coronary levels of IL-6 (r =0.566, p=0.009). Culprit coronary plaque area demonstrated a positive relation with systemic levels of hs-CRP (r =0.466, p=0.038) and also IL-6 (r =0.707, p<0.001). The present study may provide an important insight into the link between systemic and coronary levels of inflammation, which is also associated with vulnerable coronary morphology in the setting of acute coronary syndromes.


Angiology | 2006

Prevention of positive coronary artery remodeling with statin therapy in patients with coronary artery diseases

Makoto Suzuki; Makoto Saito; Takayuki Nagai; Hideyuki Saeki; Yukio Kazatani

Since positive coronary artery remodeling with large plaque burden is associated with subsequent coronary events, the authors tested their hypothesis that secondary prevention of coronary events by a statin may be associated with inhibition of the process of positive coronary artery remodeling in underlying coronary atherosclerotic lesions in patients with coronary artery diseases. They evaluated the intravascular ultrasound imaging in angiographically normal coronary lesions at baseline and after 6 months of therapy in 64 patients with coronary artery diseases. External elastic membrane area was defined as the vessel area, and the difference between the vessel and lumen area was calculated as plaque area. The relative echogenicity of coronary plaque to adventitia was evaluated as acoustic characteristics of coronary plaque. Twenty-five patients were treated with a statin and 39 patients did not receive a statin. In patients treated with a statin, plaque area decreased by 12% (p=0.013) compared to an increase in plaque area of 13% (p=0.023) in those who did not receive a statin. The vessel area was not enlarged in patients treated with a statin but did show positive remodeling in patients who had plaque progression without a statin. The relative echogenicity of plaque was unchanged in patients treated with a statin but significantly decreased in patients not receiving a statin. A statin may prevent positive coronary artery remodeling via inhibition of plaque progression in underlying coronary atherosclerotic lesions in patients with coronary artery diseases.


Journal of Cardiology | 2017

Beneficial effects of rapid introduction of adaptive servo-ventilation in the emergency room in patients with acute cardiogenic pulmonary edema

Masaki Kinoshita; Hideki Okayama; Go Kawamura; Tatsuya Shigematsu; Tatsunori Takahashi; Yoshitaka Kawata; Go Hiasa; Tadakatsu Yamada; Yukio Kazatani

BACKGROUND Adaptive servo-ventilation (ASV) at home has been used for patients with chronic heart failure. However, its effect on acute cardiogenic pulmonary edema (ACPE) is not clear. The aim of this study was to elucidate the effect of ASV use in the emergency room in patients with ACPE. METHODS We enrolled 198 consecutive patients with ACPE. Eighty patients received standard therapies, such as oxygen inhalation and vasodilators (conventional therapy group), and 118 received ASV in addition to standard therapy (ASV therapy group). ASV was initiated in the emergency room immediately after diagnosis. The procedure was switched over from ASV to endotracheal intubation (ETI) when oxygenation was insufficient. RESULTS The ETI rate in the ASV therapy group was significantly lower than that in the conventional therapy group (3% vs. 21%, p<0.01). The intensive care unit and/or high care unit length of stay in the ASV therapy group was also significantly shorter than that in the conventional therapy group (1.9±2.1 days vs. 5.3±6.8 days, p<0.01). Consequently, the hospitalization period in the ASV therapy group was shorter than that in the conventional therapy group (19.3±11.0 days vs. 26.3±16.6 days, p<0.01). CONCLUSION In patients with ACPE, rapid introduction of ASV in the emergency room reduces the need for ETI and decreases the hospitalization period.


American Journal of Cardiology | 2003

Association between initial QRS duration and no-reflow phenomenon in patients with acute left main coronary artery obstruction

Makoto Suzuki; Makoto Saito; Takayuki Nagai; Hideyuki Saeki; Hironari Tatsuno; Yukio Kazatani

341:217–225. 6. Hochman JS, Tamis JE, Thompson TD, Weaver WD, White HD, Van de Werf F, Aylward P, Topol EJ, Califf RM. Sex, clinical presentation, and outcome in patients with acute coronary syndromes. N Engl J Med 1999;341:226–232. 7. Hasdai D, Behar S, Wallentin L, Danchin N, Gitt AK, Boersma E, Fioretti PM, Simoons ML, Battler A. A prospective survey of the characteristics, treatments and outcomes of patients with acute coronary syndromes in Europe and the Mediterranean basin: The Euro Heart Survey of Acute Coronary Syndromes (Euro Heart Survey ACS). Eur Heart J 2002;23:1190–1201.


Journal of Echocardiography | 2015

A calcified amorphous tumor that developed on both sides of the atrioventricular valve annulus.

Masaki Kinoshita; Hideki Okayama; Go Kawamura; Tatsuya Shigematsu; Tatsunori Takahashi; Toru Miyoshi; Akinori Higaki; Kayo Hara; Yoshitaka Kawata; Go Hiasa; Tadakatsu Yamada; Yukio Kazatani; Yutaka Hayashi

We report a rare case of a hemodialysis patient with a calcified amorphous tumor (CAT) on both sides of the atrioventricular valve annulus. A 70-year-old female who had received hemodialysis for 23 years because of chronic glomerulonephritis presented to our hospital with acute heart failure. Echocardiography indicated the presence of mobile cardiac masses on the mitral valve and tricuspid valve annulus. We suspected the presence of a cardiac tumor or vegetation. The patient received 3 g/day sulbactam-ampicillin and 60 mg/day gentamicin. Surgery was performed on the 14th day after hospital admission. The patient underwent mitral valve replacement, tricuspid annuloplasty, and tumor resection. Based on the pathological findings, the cardiac tumor was diagnosed as a CAT.


Clinical and Experimental Hypertension | 1985

The analysis of systolic and diastolic time intervals: a more sensitive non-invasive method in the assessment of left ventricular dysfunction in the patients with essential hypertension.

Taketoshi Ito; Mareomi Hamada; Yukio Kazatani; Nishitani K; Matsuzaki K; Daimon F; Takaaki Ochi; Tatsuo Kokubu

Time indices and volumetric parameters were investigated in patients with essential hypertension subdivided into three groups according to the WHO stage classification. The ratio of ejection time (ET) and pre-ejection period (PEP), ET/PEP remained within normal range in WHO-I but decreased significantly in WHO-II and reached extremely low values in WHO-III. ET did not change in WHO-I and WHO-II but became significantly reduced in WHO-III. Prolongation of PEP in WHO-II and WHO-III increased with progression of hypertensive stage. Isovolumic relaxation time (IRT) showed the same pattern as the prolongation of PEP; positive correlation between PEP and IRT was observed (r=0.55). On the other hand, significant changes of volumetric parameters were only observed in WHO-III. These results indicated that the time indices were a more sensitive parameter than the volumetric ones in the assessment of left ventricular dysfunction in the patients with essential hypertension.

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