Biomedical subjects

N Mukohara

Publications and source records attributed to N Mukohara.

At least 19 recordsLinked to original sources

PubMed2001

Angiosarcoma causing cardiac rupture.

We report the 7th known case in the literature of cardiac angiosarcoma resulting in cardiac rupture. A 34-year-old woman was admitted presenting chest pain and pericardial effusion. After the patient had been treated for 3 months under the diagnosis of pericarditis of unknown etiology, she became hypotensive. Doppler echocardiography showed increased pericardial effusion and a communication between the right atrium and the pericardial cavity. An emergency operation was undertaken to drain the effusion and explore the etiology. We found the ruptured right atrium and the irregularly shaped tumor extending from the pericardium near the inferior caval vein to the right ventricle. There was no apparent tumor on the right atrium, but its wall was extensively thin, which we replaced with autologous pericardium. The patient died on the 44th postoperative day. Clinical diagnosis of cardiac angiosarcoma is usually very difficult. If Doppler echocardiography demonstrates pericardial effusion and find a ruptured right atrium with or without mass formation, we should suspect cardiac angiosarcoma.

Adult↗

PubMed1998

Emergency percutaneous cardiopulmonary bypass support for acute myocardial infarction.

We assessed the efficacy of emergency percutaneous cardiopulmonary bypass support (PCPS) in the treatment of patients with acute myocardial infarction complicated by cardiogenic shock. Emergency PCPS was instituted in 21 consecutive patients beginning in 1991. After the stabilization of the hemodynamics, coronary reperfusion was performed by means of coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. Of the seven patients with acute myocardial infarction involving either the left main or two-vessel territories, five survived more than 1 month, but only one patient remained alive and well after 20 months. The main cause of death for this group was low output syndrome. Four of 12 patients with acute left main trunkal occlusion in the catheter laboratory survived and showed a preserved cardiac function (mean followup 28.5 months). The main cause of death for this group was brain damage. Two patients with single-vessel territory acute myocardial infarction underwent PCPS to treat refractory ventricular fibrillation. Both patients were still alive and well at a 12-month followup. Percutaneous cardiopulmonary bypass support successfully stabilized the hemodynamics, allowing time to perform revascularization for all three groups of patients with life-threatening acute myocardial infarction. Recanalization was nevertheless unable to salvage the damaged myocardium in cases of prolonged ischemic time.

Aged↗

PubMed1997

Leriche syndrome. Surgical procedures and early and late results.

During the past thirteen years, 29 patients underwent surgical intervention for Leriche syndrome. Fifteen patients (aged forty-two to seventy-two years, average 60.7 years) underwent anatomical bypass, and 9 of them whose thrombus was confined to the infrarenal aorta received a routine graft insertion. In the other 6 whose thrombus extended to the level of the renal arteries, an open thrombectomy of the juxtarenal aorta was first performed through a transection of the infrarenal aorta under renal ischemia (4-14 minutes, average 7). Twelve elderly or high-risk patients (aged sixty-eight to eighty-four years, average 75.3 years) underwent an axillobifemoral bypass, and another 2 (fifty-eight and sixty years old, respectively) who had been operated on at an earlier time received an ascending aortobifemoral bypass. In cases of anatomical bypass, no graft has occluded and all patients but 1, who died of cerebral infarction, have an active life now. In cases of extraanatomical bypass, 5 of the 28 grafts occluded and only 6 patients have survived. The other 8 patients died of malignancy, atherosclerotic complications, or unknown causes. The 10-year survival rate was 92.9% and 29.5% in the anatomical bypass and extraanatomical bypass group, respectively. In Leriche syndrome, anatomical bypass is preferred to extraanatomical bypass if conditions permit. In the juxtarenal type, an open thrombectomy under renal ischemia is mandatory for anatomical bypass, and a transection of the infrarenal aorta facilitates this procedure. Because the patients with Leriche syndrome are elderly and harbor arteriosclerotic lesions, a careful follow-up is mandatory.

Adult↗

PubMed1997

[Rupture of the papillary muscle after percutaneous transvenous mitral commissurotomy (PTMC)--a case report].

We experienced a rare case of the mitral regurgitation due to papillary muscle rupture after percutaneous transvenous mitral commissurotomy (PTMC). This case was a seventy years old female who underwent PTMC. The cardiac tamponade and mitral regurgitation occurred after PTMC. Pericardial drainage was done immediately, and the next day the emergency operation was required. Rupture of the posterior papillary muscle was found at the operation, and mitral valve replacement was performed. Her postoperative course was uneventful and she discharged on the 26th day after the operation. We should take the papillary muscle rupture into consideration if there are severe sub-valvular lesion and shorting of the chorda.

Aged↗

PubMed1996

Surgical treatment of infective endocarditis complicated by annular infection and cerebral infarction.

The surgical treatment of nine patients with infective endocarditis (IE) complicated by annular infection and five with IE complicated by cerebral infarction is described herein. In those with annular infection, after thorough débridement of the infected tissues, valve replacement was performed at the original position in five, at the supraannular position in three, and one underwent a translocation procedure. Aortic valve replacement was able to be performed at the original position in two patients by closing the defect at the aortic annulus with a patch after through débridement. The five patients who underwent original valve position replacement recovered well. Of the three who underwent supraannular position replacement, two died of septicemia after a redo operation, and one received pacemaker implantation. The patient undergoing the translocation procedure died of intestinal infarction. In the five patients who suffered cerebral infarction due to embolus of the vegetation, valve replacement was performed between 40 h and 5 months after its onset. Although one patient died of the rapid progression of brain damage, the other four are alive and well, including two who developed mycotic cerebral aneurysm in the infarcted areas. In conclusion, early surgery for IE is mandatory irrespective of active infection, due to the high mortality and morbidity associated with serious sequelae such as annular abscess or cerebral infarction.

Abscess↗

PubMed1996

Pericardiectomy and coronary artery bypass grafting for constrictive pericarditis after heart surgery.

A 63-year-old male was operated on for chronic heart failure due to myocardial ischemia and constrictive pericarditis after heart surgery. He was in New York Heart Association (NYHA) class III under a large dose of diuretics. He underwent a pericardiectomy and coronary bypass surgery without cardiopulmonary bypass. His cardiac function improved with a patent graft. He is now, 1 year after surgery, in NYHA class I under a tapering dose of diuretics.

Cardiac Output, Low↗

PubMed1996

Surgical treatment of ventricular septal perforation with right ventricular infarction.

A 71-year-old woman underwent an emergency surgery for ventricular septal perforation together with right ventricular infarction. The perforation of the anterior septum was closed using. Dacron patch combined with a little larger bovine pericardium, the surplus of which was stitched in the surrounding viable muscle. This procedure was performed only through the infarct of the right ventricle. She has been doing well with no residual shunt and lives a normal life now.

Aged↗

PubMed1996

[Graft replacement of a thoracic aneurysm and coronary artery bypass grafting using retrograde cerebral perfusion through left thoracotomy--a case report].

A 67-year-old woman having descending thoracic aneurysm and 90% stenosis of the obtuse marginal artery underwent a concomitant operation of graft replacement of a thoracic aneurysm and coronary artery bypass grafting. The operation was performed through left posterolateral thoracotomy with total cardiopulmonary bypass using femoral artery, femoral vein and the pulmonary artery cannulation, deep hypothermia and retrograde cerebral perfusion (RGCP). RGCP was performed by high central venous pressure (17-18 mmHg) resulted from low flow perfusion of the lower body under clamping of the descending aorta. Distal coronary anastomosis was done during an initial 100ling period and proximal anastomosis was put on the replaced thoracic graft after coming off extracorporeal circulation (ECC). ECC time was 167 minutes, and RGCP time was 27 minutes. The patient did well after the operation. Postoperative coronary angiography showed the patent coronary bypass graft. We conclude that this method provides good exposure of the thoracic aorta and the coronary artery, and satisfactory brain protection.

Aged↗

PubMed1995

Mitral valve repair using an annuloplasty ring made of artificial woven Dacron graft.

A woven Dacron ring made of artificial graft was successfully used in combination with a modified Kay's annuloplasty for mitral valve repair. In this procedure, after excision and repair of the redundant prolapsed leaflets, Kay's annuloplasty was performed at both commissures to reduce the posterior annulus and to coapt the leaflets. A woven Dacron ring was then seated and tied to the annulus to provide long-term stabilization and prevent its further dilatation. The mitral orifice of the patient was reduced from 33 mm to 21 mm in diameter, and neither mitral regurgitation nor stenosis was found in the postoperative evaluation.

Female↗

PubMed1995

[A case of type A acute aortic dissection successfully treated with a ringed intraluminal graft: a new technique of graft insertion].

A-77-year old woman was hospitalized at our hospital presenting with severe chest and back pain. A computed tomographic scan revealed acute type A aortic dissection and intraoperative ultrasound showed an entry near the brachiocephalic artery. Selective cerebral perfusion using flexible 12 Fr balloons was performed for brain protection. The distal aorta was trimmed just proximal to the entry using felt strips and a 24 mm ringed intraluminal graft (ILG) was inserted under it successfully. The patient did well after the operation. Insertion of a ringed ILG is a simple and easy technique, however if an entry is located near the aortic arch, insertion is difficult because of intimal retraction to the arch. And an additional intimal tear sometimes occurs at the site of tape ligation. The method which we presented seemed to provide safer insertion of the proximal ring without these problems.

Acute Disease↗

PubMed1995

[Efficacy of terminal warm blood cardioplegia against the reperfusion injury].

The effect of terminal warm blood cardioplegia (TWBC) was evaluated from the incidence of ventricular fibrillation and myocardial metabolism after release of aortic clamping in 70 patients (group I) who underwent open heart surgery using TWBC compared with 70 patients (group II) without TWBC. The incidence of ventricular fibrillation after unclamping in group I was 19.7% which was statistically less than 68.6% in group II. Both excess lactate (delta XL) and redox potential (delta Eh) demonstrated that anearobic myocardial metabolism after reperfusion was restored more rapidly in group I than in group II. Multivariate analysis showed the incidence of ventricular fibrillation after reperfusion was related to high concentrations of both calcium and sodium and low concentration of potassium in reperfused blood in group II. But it was only related to left ventricular myocardial temperature in group I. High concentration of calcium and low concentration of potassium in reperfused blood, and low myocardial temperature were most related to anearobic metabolism of myocardium following reperfusion in group II, whereas only pH value was closely related to recovery for myocardial metabolism in group I. In conclusion, TWBC was useful for improving microcirculation in myocardium and avoiding calcium-overload to myocardial cells, and resulted in reducing reperfusion injury in myocardium. Furthermore, acid content of TWBC and enough amount to raise myocardial temperature would provide more efficacy on myocardial preservation.

Body Temperature↗

PubMed1995

[A comparison of changes of cerebrovascular oxygen saturation in retrograde and selective cerebral perfusion during aortic arch surgery].

To evaluate the effect of retrograde cerebral perfusion (RCP) and selective cerebral perfusion (SCP) on brain protection, changes of cerebrovascular oxygen saturation (rSO2) were studied in 14 patients with aortic arch reconstruction during the procedure. The rSO2 was monitored with spectroscopy instrument (Invos 3100, Somanetics). The mean value of rSO2 measured just before cardiopulmonary bypass was 65.9 +/- 6.2% in 7 patients with RCP, and was 64.9 +/- 4.7% in 7 patients with SCP. The value of rSO2 during core cooling of cardiopulmonary bypass was increased step by step. Although RCP time with a mean of 38.9 +/- 9.7 min was statistically shorter than SCP time (80.7 +/- 45.1 min), the mean value of rSO2 during cerebral protection in RCP group was decreased from 80.3 +/- 8.1% to 63.4 +/- 10.2%, lowest 46% with a ratio of 21.1%. In contrast, the mean value of rSO2 in SCP group was well maintained from 79.9 +/- 6.5 to 75.6 +/- 6.8%, lowest 63% with a ratio of 5.4%. Although no neurological deficits were recognized after operation in both groups, rSO2 in SCP group was sustained above the control value (65% just before cardiopulmonary bypass) but rSO2 in RCP group was decreased below the control value after 35 min. So we conclude that with regard to brain protection assessed from rSO2 measured by Invos 3100 cerebral oximeter, there is no time limitation of SCP during the procedure but RCP had a limit of the duration.

Aged↗

PubMed1994

The problems of surgical treatment for cardiac myxoma and associated lesions.

Twenty-four patients with cardiac myxomas consisting of 22 left and 2 right atrial myxomas were operated on. All myxomas were removed with an excision of the attachment walls using a cardiopulmonary bypass. Two myxomas required a partial cardiopulmonary bypass from the femoral vein to the artery prior to operation because they were on the verge of becoming stuck in the atrioventricular valves and potentially causing shock. For embolic complications of myxoma, the embolus of the external carotid artery was extirpated before undergoing cardiac surgery. In a patient with pulmonary infarction, the infarcted lung was resected simultaneously. Another patient with a cerebral infarction received a clipping of an aneurysm which later appeared in the infarcted area. For associated cardiac lesions, two patients underwent a coronary artery bypass graft and one mitral valve replacement with tricuspid annuloplasty. In the former two cases, the myxoma was removed prior to coronary artery bypass grafting because the use of retrograde coronary perfusion was considered to be sufficient to protect the heart. In the latter case, the removal of the myxoma first disclosed a significant mitral lesion which had been masked by the huge myxoma. All patients but one, who died of pneumonia, showed a good recovery. In this series, the problems of surgical treatment for cardiac myxoma and associated lesions are also discussed.

Adolescent↗

PubMed1994

The efficacy of non-clamping selective cerebral perfusion in distal aortic arch aneurysm repair: report of a case.

Successful repair of a distal aortic arch aneurysm without aortic cross-clamping was carried out in a 74-year-old man, using a combination of special separate cerebral perfusion and retrograde coronary perfusion, termed non-clamping selective cerebral perfusion. We believe that satisfactory results following aortic arch surgery in elderly patients can only be achieved through the prevention of emboli derived from an aortic cross-clamping site, and shortened ischemic time of the vital organs.

Aged↗

PubMed1994

Surgical treatment of ventricular septal defect and its sequelae in adults.

We operated on 20 adult patients with ventricular septal defect (VSD). In 7 of these cases (aged 36 to 51 years, average 42.6 years), VSD was accompanied by sequelae other than pulmonary hypertension. Concomitant procedures in type-I VSD included a suspension of the prolapsed aortic cusp in 2 patients, a repair of the ruptured sinus of Valsalva in 2, and a new procedure for active infective endocarditis, described below, in 2. In this latter procedure, the aortic valve and infected Valsalva sinus were excised, and the pulmonary valve and the right ventricular wall to which the infection had extended were thoroughly debrided. The resulting defect was closed with a single patch, and a prosthetic valve was inserted in the position of the original aortic valve using this patch as part of the annulus. Another patient with the type-II VSD underwent concomitant tricuspid valve replacement for infective endocarditis. In the mean follow-up period of 77.1 months, 6 patients have been doing well in New York Heart Association class I, and the remaining patient with Valsalva repair remained in class II due to dilated cardiomyopathy.

Adult↗

PubMed1994

Surgical treatment of ventricular septal defect and ruptured sinus of Valsalva associated with infective endocarditis.

Two patients with ventricular septal defect of Kirklin type I and ruptured right coronary sinus of Valsalva associated with infective endocarditis were operated on. Both had bacillus vegetation clinging to the aortic and pulmonary valves and the right ventricular intimal wall around the septal defect. Aortic and pulmonary regurgitation were also found. The surgical approach included vertical incision of the right ventricular outflow tract and pulmonary trunk and transverse aortotomy. The right coronary sinus of Valsalva showed distinct aneurysmal change in one patient. The aortic valve and infected Valsalva sinus were excised in both cases, and the pulmonary valve and right ventricular wall where infection extended thoroughly débrided. The resulting defect, including the ventricular septal defect and excised right Valsalva sinus and aortic annulus, was closed with one patch, and the prosthetic valve inserted in the position of the original aortic valve using this patch as part of the annulus. Both patients had a good postoperative course and are doing well, although slight pulmonary regurgitation persists.

Adult↗

PubMed1994

[Mitral valve replacement and right ventricular outflow repair for hypertrophic obstructive cardiomyopathy].

A 44-year-old male with hypertrophic obstructive cardiomyopathy (HOCM) was operated on. He was in NYHA class III with a chief complaint of exertional dyspnea refractory to medical treatment. Echocardiography showed asymmetric septal hypertrophy and systolic anterior movement of the mitral valve, which caused obstruction of the left ventricular outflow tract. It also showed obstruction of the right ventricular outflow tract due to septal hypertrophy. Cardiac catheterization showed a systolic pressure gradient of 70 mmHg at the LV outflow tract and that of 30 mmHg at the RV outflow tract. He underwent mitral valve replacement and patch enlargement of the RV outflow tract. Postoperative course was uneventful. Postoperative catheterization showed a remarkable decrease of pressure gradient to 10 mmHg at the both outflow tracts.

Adult↗

PubMed1994

[Surgical treatment of incomplete endocardial cushion defect in elderly patients].

We experienced 5 surgical cases of incomplete endocardial cushion defect who were 50 years old or older. Preoperatively, 3 cases were in New York Heart Association (NYHA) class II and 2 in class III. Catheterization study showed that systolic pulmonary arterial pressure was 24 to 48 (average; 38) mmHg and pulmonary-to-systemic flow ratio was 3.4 to 8.1 (average; 5.2). Left ventriculography showed mitral valve regurgitation (grade I-1 cases, grade II-3, grade III-1) with cleft and goose neck sign in all cases. Single atrium and patent foramen ovalis were associated in each one case. At operation, suture of mitral cleft and patch closure of ostium primum defect from mitral valve side were performed. Postoperatively, NYHA class, cardiomegaly, pulmonary arterial pressure and mitral regurgitation improved remarkably in all patients. During the follow-up period from 18 to 126 months (average; 57), right bundle branch block and supraventricular arrhythmia in electrocardiogram disappeared in 3 of 4 and 4 of 5 cases, respectively. Surgical treatment and postoperative course of incomplete ECD were reviewed in over-50-year-old patients, in reference to 17 surgical cases in Japan.

Electrocardiography↗