Mitsunori Nishiyama
Tokyo Medical and Dental University
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Publication
Featured researches published by Mitsunori Nishiyama.
Circulation | 2011
Takashi Kanai; Takahiro Ishiwata; Tohru Kobayashi; Hiroki Sato; Mari Takizawa; Yoichi Kawamura; Hiroshi Tsujimoto; Keigo Nakatani; Naoko Ishibashi; Mitsunori Nishiyama; Yoshiho Hatai; Yuh Asano; Tomio Kobayashi; Seiichiro Takeshita; Shigeaki Nonoyama
Background— Markedly activated neutrophils or higher plasma levels of neutrophil elastase are involved in the poor response to intravenous immunoglobulin (IVIG) and the formation of coronary artery lesions (CAL) in patients with acute Kawasaki disease. We hypothesized that ulinastatin (UTI), by both direct and indirect suppression of neutrophils, would reduce the occurrence of CAL. Methods and Results— We retrospectively analyzed the clinical records of patients with Kawasaki disease between 1998 and 2009. Three hundred sixty-nine patients were treated with a combination of UTI, aspirin, and IVIG as an initial treatment (UTI group), and 1178 were treated with a conventional initial treatment, and IVIG with aspirin (control group). The baseline characteristics did not demonstrate notable differences between the two groups. The occurrence of CAL was significantly lower in the UTI group than in the control group (3% versus 7%; crude odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25–0.86; P=0.01). The OR adjusted for sex, Gunma score (the predictive score for IVIG unresponsiveness), and dosage of initial IVIG (1 or 2 g/kg) was 0.32 (95% CI, 0.17–0.60; P<0.001). In addition, most CAL occurred in patients requiring additional rescue treatment and the proportion of those patients was significantly lower in the UTI group than in the control group (13% versus 22%; crude OR, 0.52; 95% CI, 0.38–0.73; P<0.001). The adjusted OR was 0.30 (95% CI, 0.20–0.44; P<0.001). Conclusions— UTI was associated with fewer patients requiring additional rescue treatment and reduction of CAL in this retrospective study.
Pediatric Cardiology | 2006
Naoko Ishibashi; In-Sam Park; Yukiko Takahashi; Mitsunori Nishiyama; Yasue Murakami; Katsuhiko Mori; Shigekazu Mimori; Makoto Ando; Yukihiro Takahashi; Toshio Nakanishi
We report a case of a patient with severe heart failure after Fontan procedure in whom carvedilol was very effective. A 27-year-old man had intractable congestive heart failure due to severe ventricular dysfunction after Fontan operation. Central venous pressure was elevated to 29 mmHg. A right-to-left shunt was noted across a large collateral vessel between the innominate vein and the pulmonary vein. He was administered carvedilol (initial dose, 2 mg/day; maximum dose, 30 mg/day). Cardiac catheterization performed 1 year after carvedilol administration revealed a decrease in atrial pressure and improvement of ventricular function. He underwent a conversion operation to total cavopulmonary connection (TCPC) and ligation of a collateral vein communicating with the innominate and pulmonary veins. Carvedilol may be a legitimate treatment before TCPC conversion or heart transplantation for the high-risk group of patients with a failed Fontan circulation.
Heart and Vessels | 2009
Mitsunori Nishiyama; In-Sam Park; Yoshiho Hatai; Makoto Ando; Yukihiro Takahashi; Katsuhiko Mori; Yasuo Murakami
There have been few reports describing the use of carvedilol in children or patients with congenital heart disease. Therefore, its optimal regimen, efficacy, and safety in these patients have not been adequately investigated. Subjects were 27 patients with two functioning ventricles, for whom carvedilol was initiated (from December 2001 to December 2005) to treat heart failure. All patients had failed to respond to conventional cardiac medication. They consisted of 12 males and 15 females, aged 23 days to 47 years (median age: 2 years). Heart failure due to ischemia (myocardial infarction, intraoperative ischemic event) or due to myocardial disease (cardiomyopathy, myocarditis), and heart failure with atrial or ventricular tachyarrhythmia represented 70% of all cases. Carvedilol was initiated at a dose of 0.02–0.05 mg/kg/day, which was increased by 0.05–0.1 mg/kg/day after 2 days, 0.1 mg/kg/day after 5 days, and 0.05–0.1 mg/kg/day every month thereafter with a target dose of 0.8 mg/kg/day. This study retrospectively assessed the efficacy and adverse reactions based on changes of symptoms, cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and human atrial natriuretic peptide (hANP)/b-type natriuretic peptide (BNP) blood levels. The mean follow-up period was 10.2 months (range: 1–46 months). Twenty-six (96.3%) patients showed improvement in symptoms and were discharged from the hospital. However, the remaining one patient failed to respond and died. Significant cardiovascular adverse reaction was seen in none of the patients. The mean CTR decreased from 61.8% ± 5.3% before treatment to 57.6% ± 7.4% after treatment (P < 0.05, n = 25), and the mean LVEF improved from 41.4% ± 23.1% to 61.1% ± 10.1% (P < 0.05, n = 10), respectively. Mean hANP and BNP levels showed a decrease from 239.1 pg/ml to 118.3 pg/ml and a significant decrease from 437.9 pg/ml to 120.5 pg/ml, respectively (P < 0.05, n = 10). Improvements in these data were also demonstrated when analyzed individually among the pediatric group (aged younger than 18) and the congenital heart disease group. Initiation of carvedilol at a lower dose with more gradual dose escalation, compared with previously reported regimens, might have efficacy with low incidence of adverse effects in pediatric patients and patients with congenital heart disease. Carvedilol may be effective in treating heart failure in children due to ischemia, myocardial disease, and complicated by tachyarrhythmia.
Pediatric Cardiology | 2011
Mitsunori Nishiyama; Shouzaburo Doi; Akiko Matsumoto; Masato Nishioka; Susumu Hosokawa; Akihito Sasaki; Shuki Mizutani
We report a case of anomalous origin of the left main coronary artery (LCA) from the noncoronary sinus of valsalva (LCANCS) in a young healthy patient who presented with syncope and cardiopulmonary arrest during exercise. The enhanced computed tomography showed acute angle take-off (AAT) of LCA, and the exercise stress thallium-201 myocardial scintigraphy demonstrated a large defect at the LCA perfusion region. We propose that the coexistence of AAT and resulting ischemia causes sudden cardiac death during exercise in the patients with LCANCS.
International Journal of Cardiology | 2000
Naomi Izumida; Yuh Asano; Hiroko Wakimoto; Mitsunori Nishiyama; Shouzaburoh Doi; Shirou Tsuchiya; Junro Hosaki; Seiko Kawano; Tohru Sawanobori; Masayasu Hiraoka
We examined the distributions of the activation recovery interval (ARI), which is correlated with the local action potential duration (APD), to clarify the origin of the repolarization changes in ASD. The ECGs, QRST isointegral maps and ARI isochronal maps of 21 children with ASD from 3 to 5 years old in age were studied in comparison with 21 age-matched normal children. A conventional and 87 unipolar body surface ECG were simultaneously recorded. The ARIs were determined from the first derivatives of the ECG waveforms. Abnormal ST-T patterns were observed in 11 of 21 ASD, but only in two normal children. The QRST maps of a split positive area pattern were seen in 15 of ASD but none of the normal. In the ARI maps, all the normal children exhibited a short-ARI area on the left and a long-ARI area on the right side of the chest. In 19 of ASD, the ARI distribution revealed a leftward extension of the long-ARI area on the anterior chest, a relative shortening on the right anterior chest, and a localized prolonged ARI on the left anterior chest. The results suggest that right ventricular (RV) volume overload in ASD produces a localized prolongation of the APD on the RV epicardium.
BMC Psychiatry | 2016
Mizue Hobo; Akihito Uezato; Mitsunori Nishiyama; Mayumi Suzuki; Jiro Kurata; Koshi Makita; Naoki Yamamoto; Toru Nishikawa
BackgroundIdiopathic pulmonary arterial hypertension (IPAH) is a progressive and fatal cardiovascular disease if left untreated. In patients with IPAH with psychiatric illness or other complications, careful attention is required when administering medical therapies that may affect their hemodynamics. Patients suffering from IPAH who undergo anesthesia and surgery have a high mortality and morbidity rate. We describe the treatment of intractable psychiatric symptoms with electroconvulsive therapy (ECT) in a patient with IPAH.Case presentationA 23-year-old woman with IPAH and type I diabetes mellitus (DM) presented with malignant catatonia. Her heart function was classified as New York Heart Association (NYHA) class III. She required a rapid cure and ECT due to various psychiatric symptoms resistant to conventional medications. Pulmonary hypertensive (PH) crisis is the most concerning complication that can be induced by the sympathetic stimulation of ECT. To avoid PH crisis, we administered oxygen using a laryngeal mask and administered remifentanil for anesthesia. We also prepared standby nitric oxide for possible PH crisis, although it was ultimately not needed. With 14 ECT sessions, her malignant catatonia was ameliorated without physical complications.ConclusionECT is an acceptable option for the treatment of medication-refractory psychiatric disturbances in patients with IPAH, provided careful management is assured to prevent or address complications.
Pediatric Research | 2011
Mari Takizawa; Takahiro Ishiwata; Yoichi Kawamura; Takashi Kanai; Takayuki Kurokawa; Mitsunori Nishiyama; Hideyuki Ishida; Yuh Asano; Shigeaki Nonoyama
Sarcoplasmic reticulum (SR) Ca2+ release has been shown not to be the predominant mechanism responsible for excitation-contraction (E-C) coupling in fetal myocytes. However, most of the studies have been conducted either on primary cultures or acutely isolated cells, in which an apparent reduction of ryanodine receptor density have been reported. We aimed to elucidate the contribution of SR Ca2+ release and Ca2+ transporters on sarcolemmal channels to Ca2+ transients in fetal mouse whole hearts. On embryonic day 13.5, ryanodine significantly reduced the amplitude of the Ca2+ transient to 27.2 ± 4.4% of the control, and both nickel and SEA0400 significantly prolonged the time to peak from 84 ± 2 ms to 140 ± 5 ms and 129 ± 6 ms, respectively, whereas nifedipine did not alter it. Therefore, at early fetal stages, SR Ca2+ release should be an important component of E-C coupling, and T-type Ca2+ channel and reverse mode sodium-calcium exchanger (NCX)-mediated SR Ca2+ release could be the predominant contributors. Using embryonic mouse cultured cardiomyocytes, we showed that both nifedipine and nickel inhibited the ability of NCX to extrude Ca2+ from the cytosol. From these results, we propose a novel idea concerning E-C coupling in immature heart.
Circulation | 2011
Takashi Kanai; Takahiro Ishiwata; Tohru Kobayashi; Hiroki Sato; Mari Takizawa; Yoichi Kawamura; Hiroshi Tsujimoto; Keigo Nakatani; Naoko Ishibashi; Mitsunori Nishiyama; Yoshiho Hatai; Yuh Asano; Tomio Kobayashi; Seiichiro Takeshita; Shigeaki Nonoyama
Background— Markedly activated neutrophils or higher plasma levels of neutrophil elastase are involved in the poor response to intravenous immunoglobulin (IVIG) and the formation of coronary artery lesions (CAL) in patients with acute Kawasaki disease. We hypothesized that ulinastatin (UTI), by both direct and indirect suppression of neutrophils, would reduce the occurrence of CAL. Methods and Results— We retrospectively analyzed the clinical records of patients with Kawasaki disease between 1998 and 2009. Three hundred sixty-nine patients were treated with a combination of UTI, aspirin, and IVIG as an initial treatment (UTI group), and 1178 were treated with a conventional initial treatment, and IVIG with aspirin (control group). The baseline characteristics did not demonstrate notable differences between the two groups. The occurrence of CAL was significantly lower in the UTI group than in the control group (3% versus 7%; crude odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25–0.86; P=0.01). The OR adjusted for sex, Gunma score (the predictive score for IVIG unresponsiveness), and dosage of initial IVIG (1 or 2 g/kg) was 0.32 (95% CI, 0.17–0.60; P<0.001). In addition, most CAL occurred in patients requiring additional rescue treatment and the proportion of those patients was significantly lower in the UTI group than in the control group (13% versus 22%; crude OR, 0.52; 95% CI, 0.38–0.73; P<0.001). The adjusted OR was 0.30 (95% CI, 0.20–0.44; P<0.001). Conclusions— UTI was associated with fewer patients requiring additional rescue treatment and reduction of CAL in this retrospective study.
Circulation | 2011
Takashi Kanai; Takahiro Ishiwata; Tohru Kobayashi; Hiroki Sato; Mari Takizawa; Yoichi Kawamura; Hiroshi Tsujimoto; Keigo Nakatani; Naoko Ishibashi; Mitsunori Nishiyama; Yoshiho Hatai; Yuh Asano; Tomio Kobayashi; Seiichiro Takeshita; Shigeaki Nonoyama
Background— Markedly activated neutrophils or higher plasma levels of neutrophil elastase are involved in the poor response to intravenous immunoglobulin (IVIG) and the formation of coronary artery lesions (CAL) in patients with acute Kawasaki disease. We hypothesized that ulinastatin (UTI), by both direct and indirect suppression of neutrophils, would reduce the occurrence of CAL. Methods and Results— We retrospectively analyzed the clinical records of patients with Kawasaki disease between 1998 and 2009. Three hundred sixty-nine patients were treated with a combination of UTI, aspirin, and IVIG as an initial treatment (UTI group), and 1178 were treated with a conventional initial treatment, and IVIG with aspirin (control group). The baseline characteristics did not demonstrate notable differences between the two groups. The occurrence of CAL was significantly lower in the UTI group than in the control group (3% versus 7%; crude odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25–0.86; P=0.01). The OR adjusted for sex, Gunma score (the predictive score for IVIG unresponsiveness), and dosage of initial IVIG (1 or 2 g/kg) was 0.32 (95% CI, 0.17–0.60; P<0.001). In addition, most CAL occurred in patients requiring additional rescue treatment and the proportion of those patients was significantly lower in the UTI group than in the control group (13% versus 22%; crude OR, 0.52; 95% CI, 0.38–0.73; P<0.001). The adjusted OR was 0.30 (95% CI, 0.20–0.44; P<0.001). Conclusions— UTI was associated with fewer patients requiring additional rescue treatment and reduction of CAL in this retrospective study.
Circulation | 2011
Takashi Kanai; Takahiro Ishiwata; Tohru Kobayashi; Hiroki Sato; Mari Takizawa; Yoichi Kawamura; Hiroshi Tsujimoto; Keigo Nakatani; Naoko Ishibashi; Mitsunori Nishiyama; Yoshiho Hatai; Yuh Asano; Tomio Kobayashi; Seiichiro Takeshita; Shigeaki Nonoyama
Background— Markedly activated neutrophils or higher plasma levels of neutrophil elastase are involved in the poor response to intravenous immunoglobulin (IVIG) and the formation of coronary artery lesions (CAL) in patients with acute Kawasaki disease. We hypothesized that ulinastatin (UTI), by both direct and indirect suppression of neutrophils, would reduce the occurrence of CAL. Methods and Results— We retrospectively analyzed the clinical records of patients with Kawasaki disease between 1998 and 2009. Three hundred sixty-nine patients were treated with a combination of UTI, aspirin, and IVIG as an initial treatment (UTI group), and 1178 were treated with a conventional initial treatment, and IVIG with aspirin (control group). The baseline characteristics did not demonstrate notable differences between the two groups. The occurrence of CAL was significantly lower in the UTI group than in the control group (3% versus 7%; crude odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25–0.86; P=0.01). The OR adjusted for sex, Gunma score (the predictive score for IVIG unresponsiveness), and dosage of initial IVIG (1 or 2 g/kg) was 0.32 (95% CI, 0.17–0.60; P<0.001). In addition, most CAL occurred in patients requiring additional rescue treatment and the proportion of those patients was significantly lower in the UTI group than in the control group (13% versus 22%; crude OR, 0.52; 95% CI, 0.38–0.73; P<0.001). The adjusted OR was 0.30 (95% CI, 0.20–0.44; P<0.001). Conclusions— UTI was associated with fewer patients requiring additional rescue treatment and reduction of CAL in this retrospective study.