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Biomedical subjects

R Omoto

Publications and source records attributed to R Omoto.

At least 19 recordsLinked to original sources
PubMed2004

[Long survival with chronic ventricular fibrillation under support of uni-left-ventricular assist system].

Few minutes of suspended malignant ventricular arrhythmia may be permitted for the patient with left ventricular assist system (LVAS). However, longer and continuous ventricular arrhythmia, especially ventricular fibrillation (Vf), may induce the low output of LVAS, which leads circulatory collapse immediately. Our presenting case is a female dilated cardiomyopathy patient who has been supported with LVAS. Four months after the LVAS installation, her electrocardiogram has changed to Vf without any symptoms. Her ventricular function has never recovered, even ventricular tachycardia. She has been a candidate of heart transplantation for more than 19 months with this rare hemodynamic condition (LVAS+Vf), like the Fontan circulation. Her performance status is limited due to deceasing of the LVAS flow, which caused by the change of her position: 2.5-2.9 l/min (lie down) to 2.0 l/min (rise). Her peak VO2/W is 6.9 ml/min/kg measured by the cardio-pulmonary exercise test. However, she has developed her general status by doing rehabilitation program and is able to walk for more than 100-150 meters.

Adult↗
PubMed2002

[A report of initial clinical use of left ventricular assist system with left ventricular inflow cannula for acute myocardial infarction].

Previous clinical results of left ventricular assist system (LVAS) therapy for cardiogenic shock due to acute myocardial infarction (AMI) are still unacceptable. Japanese LVAS was designed for left atrial inflow cannulation. However, to obtain higher initial LVAS flow and more decompression of left ventricular (LV) cavity and to avoid thromboembolic event, LV inflow cannulation is a preferable procedure. Therefore, LV inflow cannula for Japanese LVAS (Toyobo) was developed. We treated three AMI cases with Toyobo-LVAS using the new LV inflow cannula. All patients were in cardiogenic shock status since broad antero-septal AMI and treated with percutaneous cardio-pulmonary support before the LVAS installation. The LVAS was effective for recovery from cardiogenic shock status and multiple organ failure. Two patients died because of serious LVAS associated complications such as bleeding (case 1, 8 days) and cerebral thromboembolism (case 2, 45 days). One of them was assisted for 202 days and underwent second operation. Sixty days after removal of LVAS, the patient died due to sepsis. The technique of LV inflow cannulation is improved through our experiences. However, our result suggests that renovation of the regimen for anti-coagulation and anti-septic therapy are necessary.

Aged↗
PubMed2001

Combined coronary intervention in heart-transplant patient with rapidly accelerated cardiac allograft vasculopathy.

A 46-year-old man accepted for heart transplantation due to persistent cardiac failure from dilated cardiomyopathy underwent a transplant in Germany on July 13, 1995. The donor heart was suspected of coronary artery disease at explantation, but he could wait no longer because of his rapidly deteriorating hemodynamics. Postoperative coronary angiography revealed 25% stenosis of the left descending artery. He showed several episodes of minimal or moderate rejection postoperatively, and coronary angiography 15 months postoperatively showed rapidly accelerated cardiac allograft vasculopathy demonstrating triple vessel disease with multiple lesions. Percutaneous transluminal coronary angioplasty was successful on 2 coronary vessels, but immediately recurrent stenosis and new lesions involving the left main trunk occurred 6 weeks thereafter. Since he was financially unable to afford a second heart transplantation, quadruple coronary artery bypass grafting was conducted October 25, 1996. A biventricular assist device was used when he could not be weaned from cardiopulmonary bypass. He died of multiple organ failure 3 days after surgery.

Angioplasty, Balloon, Coronary↗
PubMed2001

Aortobiventricular fistulas associated with pseudoaneurysm of the ascending aorta 12 years after patch repair of supravalvular aortic stenosis.

Fistula formation between the aorta and cardiac chamber is a rare complication of the ascending aortic aneurysm. A 27 year-old man undergoing successful patch aortoplasty for supravalvular aortic stenosis 12 years before admission had a high fever, infectious signs in blood laboratory data, and congestive heart failure. Transthoracic and transesophageal echocardiography revealed a pseudoaneurysm of the aortic root and aortobiventricular fistulas. Detachment of the proximal end of the aortic patch was thought to be the cause of the pseudoaneurysm. Debridement of necrotic tissue surrounding fistulas produced large defects in the anterior wall of the right ventricle, interventricular septum, and ascending aorta. A modified Konno operation effectively reconstructed the outflow tracts of both ventricles and the aorta.

Adult↗
PubMed2000

Clinical effects of ventricular assist system in end-stage cardiac failure. Advantages of left ventricular blood drainage for recovery from cardiac dysfunction.

OBJECTIVES: Heart transplantation is extremely limited currently in Japan. As a consequence ventricular assist system implantation is employed the patient falls into end-stage cardiogenic shock. This preliminary report describes our initial clinical experience with use of 2 kinds of ventricular assist system for 13 Japanese patients. METHODS: 7 patients were supported by a left ventricular assist system with blood drainage from the left atrium (LA drainage Group) using a Toyobo ventricular assist system, while another 6 patients were supported by a left ventricular assist system with blood drainage from the left ventricle (LV drainage Group) using the Toyobo ventricular assist system (1 patient) or TCI-LVAS (5 patients). RESULTS: The average duration of ventricular assist system support in the LV drainage Group was 112 days including two on-going patients (now at 39 days and 241 days) and in the LA drainage Group was 49 days. The average left ventricular ejection fraction at 3 weeks after ventricular assist system implantation was improved from 12.3 to 54% using the TCI-LVAS and from 14 to 33% using the Toyobo ventricular assist system with drainage from the left ventricle. However, this was decreased from 20 to 10% using the Toyobo ventricular assist system with drainage from the left atrium. The ventricular assist system was explanted in 4 patients (31%) with recovery of cardiac dysfunction and 3 were long survivors. The 2 on-going patients are awaiting heart transplantation. Thus the current survival rate overall is 38%. The survival rate (67%) is excellent in the LV drainage Group including 2 long survivors after explantation. CONCLUSION: Ventricular assist system support with drainage from the left ventricle seems to be more advantageous for cardiac functional recovery than from the left atrium for end-stage heart failure.

Adult↗
PubMed2000

Clinical experience of milrinone as a pharmacological bridge to heart transplantation.

A 19-year-old man with idiopathic dilated cardiomyopathy developed cardiogenic shock. A HeartMate left ventricular assist device was inserted as an emergency procedure, but removed after 189 days due to sepsis related to the device. Intravenous milrinone was administered because of recurrence of heart failure, and as a result the symptoms disappeared and the urinary output increased. Echocardiography showed improvement in the left ventricular ejection fraction. Subsequently, the patient successfully underwent heart transplantation. Milrinone was effective as a pharmacological bridge to heart transplantation in this patient with terminal and critical heart failure after removal of a left ventricular assist device.

Adult↗
PubMed2000

Development and clinical application of minimally invasive cardiac surgery using percutaneous cardiopulmonary support.

OBJECTIVES: Optimal cardiopulmonary support during minimally invasive cardiac surgery remains controversial. We developed cardiopulmonary bypass for minimally invasive cardiac surgery using percutaneous peripheral cannulation. METHODS: Subjects were 34 patients (age: 58 +/- 13 years; range: 17-73) undergoing minimally invasive cardiac surgery using percutaneous cardiopulmonary support between June 1997 and March 1999. Procedures included atrial septal defect closure (n = 14), partial atrioventricular septal defect closure (n = 1), mitral valve replacement (n = 8), mitral valve repair (n = 3), aortic valve replacement (n = 6), coronary artery bypass grafting (n = 1), and right atrial myxoma extirpation (n = 1). Bicaval venous drainage from the right internal jugular vein and the femoral vein and arterial return to the femoral artery were instituted by percutaneous cannulation. Venous drainage was implemented by negative pressure (-20 to -40 mmHg) and arterial return was by conventional roller pump. All procedures were conducted through a skin incision 8 +/- 1 cm, from 6 to 10 cm and partial sternotomy. Aortic cross clamping and cardioplegic solution were administered in the surgical field. RESULTS: The operation lasted 224 +/- 45 min., cardiopulmonary bypass 104 +/- 32 min., and aortic clamping 77 +/- 23 min.. No deaths occurred. One patient with residual atrial septal defect required reoperation through the same skin incision. Only 1 patient required homologous blood transfusion. The average postoperative hospital stay was 15 +/- 5 days. CONCLUSIONS: Minimally invasive cardiac surgery using percutaneous cardiopulmonary support is safe and an excellent option for selected patients affected by single valve lesion, simple cardiac anomalies, and coronary artery bypass grafting.

Adolescent↗
PubMed2000

Autologous blood transfusion in patients with hepatocellular carcinoma undergoing hepatectomy.

BACKGROUND: Homologous blood transfusion (HBT) has the risk of an immunosuppressive effect and may adversely affect the prognosis of patients with carcinomas. Autologous blood transfusion (ABT) has not yet become a standard procedure in gastroenteric cancer surgery. We investigated the usefulness and problems of ABT combined with the use of recombinant human erythropoietin (rh-EPO). METHODS: An evaluation of autologous blood transfusion (ABT) combined with recombinant human erythropoietin (rh-EPO) treatment was conducted in 46 patients with hepatocellular carcinoma undergoing hepatectomy. Preoperative autologous blood donation (ABD) was accomplished for 25 of the 46 patients. The preoperative changes in hemoglobin and hematocrit in relation to route of administration of erythropoietin were studied. In addition, intraoperative blood requirements and the postoperative complications for patients who predonated were compared with those of patients who underwent surgery without autologous predonation. RESULTS: The proportion of patients not requiring additional homologous blood transfusions (HBT) during operation was significantly higher in the ABD group than in the non-ABD group (88% versus 38%). The incidence of postoperative complications was significantly higher in patients receiving HBT than in nontransfused patients and in those receiving ABT. CONCLUSIONS: Preoperative autologous blood donation in combination with rh-EPO therapy markedly reduced the requirement for homologous blood transfusion during surgery in patients with hepatocellular carcinoma having hepatectomy.

Blood Transfusion, Autologous↗
PubMed2000

Redo without transfusion in a patient with idiopathic thrombocytopenic purpura.

Mitral valve replacement was able to be carried out at redo operation requiring neither allogeneic platelet nor blood transfusion in a patient with idiopathic thrombocytopenic purpura, by means of preoperative high-dose intravenous gamma-globulin, autologous blood predonation, use of a centrifugal pump, heparin-coated extracorporeal circuits, and simultaneous splenectomy.

Extracorporeal Circulation↗
PubMed2000

Global myocardial ischemia as a complication of an acute type A aortic dissection--rapid diagnosis of a case by transesophageal echocardiography.

A 36-year-old female was admitted for severe chest pain followed by profound shock. Electrocardiography showed severe ST segment depression (0.5-0.7 mV) in all leads except aVR and aVL. Echocardiography revealed an intimal flap in the ascending aorta and coexisting grade 3 aortic regurgitation. She was immediately intubated and transferred to the intensive care unit. Transesophageal echocardiography (TEE) demonstrated an intimal tear at 2 cm above the sinotubular junction, and the ostium of the left main trunk was oppressed by the intimal flap during diastole. Emergency graft replacement of the ascending aorta and aortic hemiarch concomitant with aortic valve resuspension was performed successfully. The ECG changes reversed to normal immediately after the operation. The patient was extubated 2 days postoperatively and discharged from the hospital 14 days postoperatively. TEE is useful for the rapid evaluation of coronary malperfusion as a complication of acute aortic dissection, especially in patients with hemodynamic instability.

Acute Disease↗
PubMed1999

Correlation of anatomic and hemodynamic features with aortic valve leaflet deformity in doubly committed subarterial ventricular septal defect.

The records of 153 patients with doubly committed subarterial ventricular septal defect (DCVSD) who underwent intracardiac repair were analyzed to evaluate factors responsible for aortic valve leaflet deformity. The patients were divided into two groups according to their echocardiographic and angiographic features as well as anatomic findings at operation: DCVSD without (17/153, 11.1%) and with arterial valve offsetting (136/153, 88.9%). Aortic regurgitation (AR) was much more prevalent in the patients with (50.0%) than in those without leaflet deformity (2.2%, P < 0.01). Arterial valve offsetting is one of the major contributing factors to the development of leaflet deformity, accounting for 5.9% in the patients without offsetting and 46.3% in those with offsetting (P < 0.01). Among the patients with arterial valve offsetting, the pulmonary-to-systemic pressure ratio was significantly higher (P < 0.01) in the patients without (0.76 +/- 0.14) than in those with leaflet deformity (0.36 +/- 0.12), suggesting that pulmonary hypertension might prevent the aortic valve leaflet from prolapsing in DCVSD. In addition, increased severity of aortic valve leaflet deformity and subsequent AR were observed with increasing age. These results suggest that aging and the presence of arterial valve offsetting as well as the absence of pulmonary hypertension might be factors responsible for aortic valve leaflet deformity and subsequent AR in DCVSD. The anatomic and hemodynamic features in DCVSD have a great impact on the development of aortic valve leaflet deformity and subsequent AR.

Adolescent↗