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Dive into the research topics where Takeyoshi Kunieda is active.

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Featured researches published by Takeyoshi Kunieda.


Journal of the American College of Cardiology | 1998

Plasma Brain Natriuretic Peptide Levels Increase in Proportion to the Extent of Right Ventricular Dysfunction in Pulmonary Hypertension

Noritoshi Nagaya; Toshio Nishikimi; Yoshiaki Okano; Masaaki Uematsu; Toru Satoh; Shingo Kyotani; Sachio Kuribayashi; Seiki Hamada; Mikio Kakishita; Norifumi Nakanishi; Makoto Takamiya; Takeyoshi Kunieda; Hisayuki Matsuo; Kenji Kangawa

OBJECTIVES This study sought to investigate the influence of right ventricular (RV) hemodynamic variables and function on the secretion of brain natriuretic peptide (BNP) in patients with isolated RV overload. BACKGROUND Plasma BNP is known to increase in proportion to the degree of left ventricular (LV) overload. However, whether BNP secretion is also regulated in the presence of RV overload remains unknown. METHODS Plasma BNP and atrial natriuretic peptide (ANP) levels in the pulmonary artery were measured in 44 patients with RV overload: 18 with RV volume overload (RVVO) due to atrial septal defect and 26 with RV pressure overload (RVPO) due to primary or thromboembolic pulmonary hypertension. Right heart catheterization was performed in all patients. RV and LV ejection fraction, myocardial mass and volume of the four chambers were determined by using electron beam computed tomography. RESULTS Although both plasma BNP and ANP levels were significantly elevated in patients with RV overload compared with values in control subjects, plasma BNP and the BNP/ANP ratio were significantly higher in patients with RVPO than with RVVO (BNP 294 +/- 72 vs. 48 +/- 14 pg/ml; BNP/ANP 1.6 +/- 0.2 vs. 0.8 +/- 0.2, both p < 0.05). Plasma BNP correlated positively with mean pulmonary artery pressure (r = 0.73), total pulmonary resistance (r = 0.79), mean right atrial pressure (r = 0.79), RV end-diastolic pressure (r = 0.76) and RV myocardial mass (r = 0.71); it correlated negatively with cardiac output (r = -0.33) and RV ejection fraction (r = -0.71). Plasma BNP significantly decreased from 315 +/- 120 to 144 +/- 54 pg/ml with long-term vasodilator therapy (total pulmonary resistance decreased from 23 +/- 4 to 15 +/- 3 Wood U). CONCLUSIONS Plasma BNP increases in proportion to the extent of RV dysfunction in pulmonary hypertension.


Journal of the American College of Cardiology | 1999

Effect of orally active prostacyclin analogue on survival of outpatients with primary pulmonary hypertension

Noritoshi Nagaya; Masaaki Uematsu; Yoshiaki Okano; Toru Satoh; Shingo Kyotani; Fumio Sakamaki; Norifumi Nakanishi; Kunio Miyatake; Takeyoshi Kunieda

OBJECTIVES This study sought to investigate the effect of beraprost sodium (BPS), an orally active prostacyclin analogue, on the survival of outpatients with primary pulmonary hypertension (PPH). BACKGROUND Continuous intravenous administration of epoprostenol (prostacyclin) has been shown to improve survival in PPH. However, the effect of oral BPS on survival in PPH remains unknown. METHODS Fifty-eight consecutive patients with PPH who could be discharged after the first diagnostic catheterization for PPH were retrospectively divided into two groups: patients treated with BPS (BPS group, n = 24) and those without BPS (conventional group, n = 34). The baseline demographic and hemodynamic data did not significantly differ between the two. RESULTS Twenty-seven patients died of cardiopulmonary causes in the conventional group during a mean follow-up period of 44 +/- 45 months. In contrast, only 4 patients died of cardiopulmonary causes in the BPS group during a mean follow-up period of 30 +/- 20 months. In a subsample (n = 15) of patients in the BPS group, mean pulmonary arterial pressure and total pulmonary resistance significantly decreased, respectively, by 13% and 25% during a mean follow-up period of 53 days. Among the variables previously known to be associated with the mortality in PPH, the absence of BPS therapy and the reduced cardiac output were independently related to the mortality by a multivariate Cox proportional hazards regression analysis (both p < 0.05). The Kaplan-Meier survival curves demonstrated that the one-, two- and three-year survival rates for the BPS group were 96%, 86% and 76%, respectively, as compared with 77%, 47% and 44%, respectively, in the conventional group (log-rank test, p < 0.05). CONCLUSIONS The oral administration of BPS may have beneficial effects on the survival of outpatients with PPH as compared with conventional therapy alone.


The Lancet | 1997

Orally active prostacyclin analogue in primary pulmonary hypertension

Yoshiaki Okano; Takao Yoshioka; Akito Shimouchi; Toru Satoh; Takeyoshi Kunieda

After the patients hadgiven their informed consent to take part, we didhaemodynamic investigations with pulmonary and peripheralarterial catheters. We assessed acute responses after the firstsix patients had received one dose of beraprost sodium(about 2 µg/kg). Measurements were taken again after tenpatients had received a daily dose of 80–180 µg for anaverage of 2 months. Pulmonary arterial pressure andresistance decreased by 12% and 26%, respectively (table),although one patient did respond more acutely. Threepatients (cases 1, 2, and 10) did not show any improvementin their symptoms and died within 6 months. Another patient(case 4) died suddenly after 18 months. In the remainingeight patients there were improvements in functional class, asdefined by New York Heart Association functional class. Allthese patients were still alive with the same dose of beraprostsodium during a mean of 5 (range 12–38; SD 8) months offollow-up. At the start of treatment, there were some minorcomplications such as flushing and headaches.A quarter of the patients with severe symptoms did notshow any improvement. However, most patients respondedwell to long-term beraprost sodium therapy, although therewere few acute responses. All our patients had a functionalstatus of III or IV, and ten of them had a mixed venousoxygen saturation below 63%, which is associated with apoor prognosis.


Journal of the American College of Cardiology | 1997

Characteristics of Pulmonary Artery Pressure Waveform for Differential Diagnosis of Chronic Pulmonary Thromboembolism and Primary Pulmonary Hypertension

Yasunori Nakayama; Norifumi Nakanishi; Masaru Sugimachi; Hiroshi Takaki; Shingo Kyotani; Toru Satoh; Yoshiaki Okano; Takeyoshi Kunieda; Kenji Sunagawa

OBJECTIVES The accurate diagnosis of chronic pulmonary thromboembolism (CPTE) is a prerequisite for life-saving surgical interventions. To help in the differential diagnosis of CPTE and primary pulmonary hypertension (PPH), we characterized the configuration of the pulmonary artery pressure waveform. BACKGROUND Because CPTE predominantly involves the proximal arteries, whereas PPH involves the peripheral arteries, we hypothesized that patients with CPTE would have stiff or high resistance proximal arteries, whereas those affected by PPH would have high resistance peripheral arteries. These differences in the primary lesions would make arterial pulsatility relative to mean pressure larger in CPTE than in PPH. METHODS In 34 patients with either CPTE (n = 22) or PPH (n = 12) whose pulmonary systolic pressure was > or = 50 mm Hg, we measured pulmonary artery pressure using a fluid-filled system that included a balloon-tipped flow-directed catheter. RESULTS To quantify the magnitude of pulsatility relative to mean pressure, we normalized pulse pressure by mean pressure, hereinafter referred to as fractional pulse pressure (PPf). PPf was markedly higher in CPTE than in PPH (mean [+/-SD] 1.41 +/- 0.20 and 0.80 +/- 0.18, respectively, p < 0.001) and was diagnostic in separating the two groups without overlap. Similarly, the coefficient of variation of pulmonary artery pressure also separated the two groups without overlap (0.45 +/- 0.06 and 0.25 +/- 0.06, respectively, p < 0.001). Fractional time to half the area under the pressure curve separated the two groups reasonably well (0.35 +/- 0.02 and 0.43 +/- 0.03, respectively, p < 0.001). CONCLUSIONS The analysis of pulsatility of pulmonary artery pressure is useful in the differential diagnosis of CPTE and PPH.


Human Pathology | 1988

Nodular regenerative hyperplasia of the liver associated with primary pulmonary hypertension

Chikao Yutani; Masami Imakita; Hatsue Ishibashi-Ueda; Shumpei Okubo; Masahiro Naito; Takeyoshi Kunieda

Nodular regenerative hyperplasia (NRH), a rare hyperplastic condition of the liver, is reported in two patients with primary pulmonary hypertension (PPH). The first patient was a 26-year-old man who died of PPH and showed multiple NRH without cirrhosis of the liver. The second patient was a 25-year-old man who had a PPH with pulmonary arterial thrombi and NRH of the liver. NRH has been described in association with immune disease, hematopoietic disorder, and diabetes mellitus, so that NRH with PPH is considered to be very rare. Histologic findings of the lungs show typically plexogenic pulmonary arteriopathy in both cases, and the livers of these patients are composed of multiple nodules that are histologically represented by slightly larger hepatocytes arranged in a cobblestone-like fashion, and are ultramicroscopically characterized by massive proliferation of mitochondria. The pathogenetic association of nodular regenerative hyperplasia with primary pulmonary hypertension will be discussed.


Journal of Thrombosis and Thrombolysis | 2006

Risk factors of acute pulmonary thromboembolism in Japanese patients hospitalized for medical illness: results of a multicenter registry in the Japanese society of pulmonary embolism research

Mashio Nakamura; Masahito Sakuma; Norikazu Yamada; Nobuhiro Tanabe; Norifumi Nakanishi; Yoshiyuki Miyahara; Takayuki Kuriyama; Takeyoshi Kunieda; Kunio Shirato; Tsuneaki Sugimoto; Takeshi Nakano

AbstractBackground: Although the prophylaxis of acute pulmonary thromboembolism (APTE) in hospitalized patients has been improving in Japan, there is no report concerning APTE of Japanese medical patients. Therefore, the present study was designed to investigate the characteristics of APTE in Japanese patients hospitalized for medical illness, through a retrospective study. Methods: In a total of 1,438 registry patients with pulmonary thromboembolism for recent 10 years, 1,027 patients with APTE were analyzed with respect to underlying diseases or predisposing factors, and clinical course. Results: A hundred thirty three patients hospitalized for medical illness developed APTE, among 433 in-hospital APTE patients. The prevalence of APTE in women was more than in men. The mean age of the patients at diagnosis was 61 ± 17 years. Main risk factors were a prolonged immobilization, stroke, cancer, indwelling central venous catheter. Fifty-four patients had 3 or more risk factors. In-hospital mortality rate was 23%. Conclusions: Japanese patients in this registry had almost the same findings as in western patients, except for some points that had the possibility of demonstrating a difference between westerners and Japanese in the development of APTE. Our results will be available for establishing the prevention of APTE in medical patients in Japan.


American Journal of Cardiology | 1997

Shortening of Doppler-Derived Deceleration Time of Early Diastolic Transmitral Flow in the Presence of Pulmonary Hypertension Through Ventricular Interaction

Noritoshi Nagaya; Toru Satoh; Masaaki Uematsu; Yoshiaki Okano; Shingo Kyotani; Norifumi Nakanishi; Takeyoshi Kunieda

Deceleration time (DT) of the early transmitral flow velocity has recently been highlighted as a simple, noninvasive indicator of pulmonary arterial wedge pressure. In patients with pulmonary hypertension without left-sided heart disease, however, increased right ventricular pressure may result in an abnormal ventricular septal motion, which may impact on left ventricular (LV) early diastolic filling. We sought to determine if DT may be influenced by the severity of pulmonary hypertension in patients without left-sided heart disease. Doppler-derived transmitral flow and hemodynamic parameters were simultaneously assessed in 26 patients with pulmonary hypertension (primary pulmonary hypertension = 11; chronic thromboembolism = 15). Transmitral Doppler variables including DT were correlated with hemodynamics and LV deformity index measured in early diastole with 2-dimensional echocardiography. DT significantly correlated with the total pulmonary resistance (r = -0.70, p <0.001). Multivariate analysis revealed that DT was independently determined by total pulmonary resistance, but not by pulmonary arterial wedge pressure, heart rate, or patients age in our study population. DT showed a correlation with LV deformity index (r = -0.74, p <0.001). These results indicate that DT may shorten in association with the severity of pulmonary hypertension and that the shortened DT in pulmonary hypertension may be attributable to right ventricular pressure overload which causes geometric changes.


Pathology International | 1993

Pulmonary hypertension due to tumor emboli: A report of three autopsy cases with morphological correlations to radiological findings

Chikao Yutani; Masami Imakita; Hatsue Ishibashi-Ueda; Michiaki Katsuragi; Takao Yoshioka; Takeyoshi Kunieda

Three cases of pulmonary hypertension caused by tumor emboli to the lungs are described. Two of the three cases had a clinical diagnosis of pulmonary thromboembolism until surgical embolectomy, and the other had a diagnosis of primary pulmonary hypertension. Autopsy disclosed chondrosarcoma, choriocarcinoma and gastric cancer as the primary tumors, respectively. Pulmonary vascular obstruction due to tumor embolism leading to pulmonary hypertension is a previously rare clinical entity, and obstructed pulmonary vessels are believed to tend to be small vessels. We compared the autopsy and radiological findings and concluded that pulmonary tumor embolism involved not only the small peripheral arteries but also the segmental and/or lobar arteries.


Thorax | 1999

Pulmonary artery sarcoma diagnosed using intravascular ultrasound images

Yoshiaki Okano; Toru Satoh; Teiji Tatewaki; Takeyoshi Kunieda; Satoru Fukuyama; Naoki Miyazaki; Yasuo Beppu

Primary and secondary malignant intravascular tumours of the pulmonary artery occur infrequently and the diagnosis is usually delayed as symptoms and findings from conventional examinations are non-specific. The case is presented of a patient with a pulmonary artery sarcoma, probably arising from ribs resected some years previously, in which intravascular ultrasound (IVUS) provided important diagnostic findings.


Nephron | 1997

Crescentic glomerulonephritis and elevated antimyeloperoxidase antibody in a patient with Churg-Strauss syndrome.

Junichi Minami; Hatsue Ishibashi-Ueda; Yoshiaki Okano; Takashi Inenaga; Norifumi Nakanishi; Takeyoshi Kunieda; Chikao Yutani

A 45-year-old man with a long history of bronchial asthma was admitted to the National Cardiovascular Center with complaints of severe pain, swelling, and ecchymoses of the lower extremities. A diagnosis of Churg-Strauss syndrome was made because of marked eosinophilia, vasculitis, and a history of asthma. Urinalysis revealed severe proteinuria and microscopic hematuria. A renal biopsy demonstrated extensively crescentic glomerulonephritis. The antineutrophil cytoplasmic antibody against myeloperoxidase (MPO-ANCA) level, determined by enzyme-linked immunosorbent assay (ELISA), was 494 ELISA units. Under treatment with prednisolone, the symptoms and eosinophilia improved within 3 days. The MPO-ANCA level decreased to its lowest value, and renal function was ameliorated within 3 months. The patient has been followed regularly on an ambulatory basis with a regimen of prednisolone.

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