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Biomedical subjects

H Hirose

Publications and source records attributed to H Hirose.

At least 361 records · Page 20Linked to original sources
PubMed1987

Problems in the modified Fontan operation for univentricular heart of the right ventricular type.

Thirteen patients (ages 4 to 16 years) with univentricular heart of right ventricular type, nine with double-inlet right ventricle (DIRV), and four with mitral atresia who underwent a modified Fontan operation were reviewed. Among those with DIRV, right isomerism with a common atrioventricular (AV) valve was found in eight and situs inversus in one; among those with mitral atresia, AV discordance was found in two and concordance in two. Intra-atrial routing using a baffle with atriopulmonary anastomosis was the main procedure (11 patients). There were two operative deaths (one DIRV, one mitral atresia) and three hospital deaths, with an early mortality of 38.5% overall (DIRV 44%, mitral atresia 25%). Low cardiac output was the main cause of death, with relatively high right atrial pressure and with tachyarrhythmias in most of the patients. Mortality was 75% for patients with DIRV who had total anomalous pulmonary venous drainage (n = 4) and 20% for those without (n = 5). Preoperative ventricular volume and ejection fraction were not different between those with severely low cardiac output (n = 4, three deaths) and the others, whereas ventricular mass/volume ratio was significantly lower in the former group. Two late deaths (one DIRV, one mitral atresia) related to the AV valve regurgitation. These results may indicate a relatively poor outcome after the modified Fontan operation for patients with univentricular heart of right ventricular type as a result of basic anatomic and hemodynamic problems.

Arteriovenous Shunt, Surgical↗
PubMed1987

Reconsiderations of indications for open mitral commissurotomy based on pathologic features of the stenosed mitral valve. A fourteen-year follow-up study in 347 consecutive patients.

From January 1972 to December 1984, 347 consecutive patients underwent open mitral commissurotomy for mitral stenosis. Commissurotomy was performed in 86% of 404 patients undergoing mitral valve operations for stenosis during the same period. These 347 patients had three different types of mitral stenosis: type I, mobile cusps without subvalvular changes (43 patients); type II, thickened cusps with subvalvular changes (210 patients); type III, rigid cusps with severe subvalvular changes (94 patients). Concomitant mild mitral regurgitation was seen in 87 patients (25.1%) and mild to moderate valve calcification in 61 patients (17.6%). There were eight early deaths (2.3%) and 12 late deaths (3.5%), yielding an actuarial survival rate of 94.6% (excluding early deaths) 14 years after operation. There were 17 reoperations (5.0%) The actuarial rates of freedom from reoperation were as follows: 83.8% at 14 years for the entire series; 73.5% for type I stenosis; 88.9% for type II; 84.0% for type III; 91.7% for mitral stenosis with calcification; 82.6% for stenosis without calcification; 90.6% for pure mitral stenosis; and 52.5% for stenosis combined with regurgitation (p less than 0.05). Postoperative effective mitral valve areas calculated according to the hydraulic formula were 2.52 cm2 (mean) at rest and 3.06 cm2 during exercise in six patients with type I stenosis, 2.21 and 2.48 cm2, respectively, in 10 with type II, and 1.85 and 1.87 cm2, respectively, in 14 with type III. Our data clearly demonstrated that open mitral commissurotomy provided excellent long-term results with acceptable valve function and a low incidence of reoperation in patients with pure mitral stenosis not combined with regurgitation, even when associated with severe subvalvular changes with or without mild to moderate valve calcification.

Adolescent↗
PubMed1987

[A case of carotid body tumor. A review of 84 cases in Japanese literature].

We encountered one case of carotid body tumor. The patient was a 63-year-old man. The tumor was 5 cm X 6 cm in size, and it was strongly adhered to the carotid artery. Therefore, the tumor was removed with combined resection of the adherent lesion of the carotid artery. During the operation, we used a temporary external bypass method to prevent brain damage. The resected part of the carotid artery was reconstructed with saphenous vein graft. Angiogram one year after operation showed good patency of the graft. In Japanese literature, this is the second report of carotid body tumor removed by temporary bypass and the first report of use of a external bypass tube.

Aged↗
PubMed1987

Ultrastructural assessment of the infant myocardium receiving crystalloid cardioplegia.

The effectiveness of cold crystalloid potassium cardioplegia was evaluated in 26 infants (age 27 days to 17 months, 7.5 +/- 5.2 months, mean +/- SD) who underwent intracardiac repair for various cardiac lesions. A myocardial biopsy sample was obtained before aortic cross-clamping (AXC) and 20 min after release of AXC (AXC time 22 to 161 min, mean 68 +/- 37 min), and semiquantitative assessment of the mitochondrial structure was made by scoring. The post-AXC score was significantly higher than the pre-AXC score (1.1 +/- 0.6 vs 0.4 +/- 0.4, p less than .001) for the whole group. Patients receiving preoperative catecholamine support had higher pre- and post-AXC scores than those who did not (pre-AXC score 0.7 +/- 0.4 vs 0.2 +/- 0.3, p less than .01; post-AXC score 1.4 +/- 0.5 vs 1.0 +/- 0.5, p less than .05). Infants less than 3 months old (n = 7) and those 3 to 12 months old (n = 11) had higher pre AXC scores than infants over 12 months old (n = 8). With respect to post-AXC score, only those less than 3 months old had significantly higher values than the other infants. These results indicate that the myocardial injury was not fully prevented by crystalloid potassium cardioplegia in infants, and that infants with preoperative heart failure and less than 3 months old appear to have increased myocardial susceptibility to ischemic injury under cardioplegia.

Aorta↗
PubMed1987

Effects of indomethacin and cold-stress on gastric acid secretion and ulceration. The effects of anti-acid secretory agents in rats.

Gastric ulcerations induced in rats by a combination of indomethacin and cold-stress (5 +/- 1 degrees C) for 6 hr were more severe than those induced by indomethacin or cold-stress alone. The acidity of gastric juice was increased in rats treated with indomethacin plus cold-stressed. Histamine H2 receptor antagonists, (H+-K+) ATPase inhibitors and prostaglandins inhibited gastric ulcer formation in indomethacin plus cold-stress treated rats, whereas anticholinergics aggravated the ulceration. The indomethacin plus cold-stress induced acid secretion was inhibited by cimetidine and omeprazole in pylorus-ligated rats. Atropine had less effect on the increase in acidity than cimetidine and omeprazole. These findings indicate that the ulcer formation in indomethacin plus cold-stress treated rats is related the increased in acidity of gastric juice. This gastric ulcer model may be useful for evaluating antiulcer agents.

Animals↗
PubMed1986

Long-term results of direct-current cardioversion after open commissurotomy for mitral stenosis.

For a 7-year period, cardiac rhythm before and after surgery was determined in 106 patients with mitral stenosis presenting with atrial fibrillation (AF) who had undergone open mitral commissurotomy. Forty-three of the patients reverted to sinus rhythm (SR) after primary or secondary direct-current (DC) cardioversion after surgery and maintained it until discharge from hospital. Thirty patients maintained SR for 3 months to 7.2 years (mean 2.5 years) after surgery. The actuarial maintenance rate of SR was 50% 7 years after surgery in these 43 patients. The duration of AF, preoperative left atrial dimension by M-mode echocardiogram and pathologic classification of the mitral valve were factors supposedly influencing the maintenance of SR for a long period after DC cardioversion. In 30 patients who reverted back to SR and maintained SR late postoperatively, the preoperative duration of AF was up to 5 years, and 35% of the patients had had AF for more than 1 year. Also, in 40% of these 30 patients, the preoperative cardiothoracic ratio was more than 60%. It is concluded that if sinus rhythm is restored by DC cardioversion before discharge from hospital after open mitral commissurotomy, it has a 50% chance of being maintained for 7 years after surgery. Long duration of AF and large cardiothoracic ratio should probably not dissuade one from attempting secondary DC cardioversion in these patients.

Adult↗
PubMed1986

Coronary sinus blood flow and myocardial oxygen consumption after valve replacement for aortic insufficiency.

Seven cases are reviewed in which the aortic valve was replaced with a Björk-Shiley tilting disk valve to treat aortic insufficiency. Comparative studies were made to determine coronary sinus blood flow (CSF) and myocardial oxygen consumption (MVO2) by using a continuous thermodilution method both before and after the operation. Additionally, indexes of left ventricular function were obtained by catheterization of the right and left heart and by left ventriculography. Postoperative total CSF decreased significantly compared with the preoperative value (p less than 0.02). However, in all cases, the postoperative CSF per 100 g of left ventricle (LV) increased compared with the preoperative measurement (p less than 0.001). The CSF per beat per 100 g LV also increased postoperatively (p less than 0.001). Total MVO2 decreased postoperatively (p less than 0.02). However, the MVO2 per unit mass tended to increase postoperatively; these increases were not significant. Postoperatively the left ventricular mass and left ventricular wall stress decreased considerably. The left ventricular ejection fraction (EF) and the mean velocity of circumferential fiber shortening (mVCF) remained at normal levels, whereas the left ventricular function improved markedly. In short, the total CSF decreased, along with LVM and left ventricular wall stress. However, because CSF per unit mass increased and EF and mVCF remained at normal values, it is assumed that the increase in CSF is associated with improvement in postoperative contractility.

Adult↗
PubMed1986

Optimum dose of cold potassium cardioplegia for patients with chronic aortic valve disease: determination by left ventricular mass.

Twenty-eight patients with chronic aortic valve disease and left ventricular (LV) hypertrophy who underwent aortic valve replacement were studied. Angiographically obtained LV mass ranged from 113 to 580 gm (average, 292 gm). In 14 patients, the LV mass per square meter of body surface area was 200 gm or more. Cold glucose-insulin-K+ cardioplegic solution was infused to obtain a myocardial temperature of less than 15 degrees C. The initial dose of cardioplegic solution was increased to as much as 25 mL per kilogram of body weight when LV hypertrophy was severe. The initial dose was standardized by LV mass and ranged from 1.0 to 3.6 ml/gm (average, 2.7 ml/gm). Postoperative peak levels of the myocardial-specific isoenzyme of creatine phosphokinase (CPK-MB) showed no significant relationship to aortic cross-clamp time, but were related significantly to LV mass (r = 0.457, p less than 0.02). The initial dose of cardioplegic solution per LV mass and the peak CPK-MB had an inverse relationship (r = -0.753, p less than 0.001). Also, peak CPK-MB was significantly lower in those patients with an initial dose of cardioplegic solution per LV mass of 2.5 ml/gm or more regardless of the size of the LV mass (300 gm or more and less than 300 gm) in spite of no significant difference in myocardial temperature. These results indicate that the dose determination of cardioplegic solution by LV mass seems desirable for patients with chronic aortic valve disease and LV hypertrophy even when myocardial temperature is monitored.

Adult↗
PubMed1986

Enlargement of rat submandibular salivary gland induced by single amputation of lower incisor teeth. Histological, histometric and ultrastructural studies.

Histological, histometric and ultrastructural studies of rat submandibular salivary glands (SMG) following single amputation of lower incisor teeth were made. The SMG enlargement occurred after the tooth amputation, and its maximal increase of weight was reached 7 days later. The results of histological and histometric observations showed that the enlargement of SMG was due to both hypertrophy and hyperplasia of the acinar cells, and hypertrophic acinar cells were ultrastructurally characterized by well-developed organelles such as rough-surfaced endoplasmic reticulum and Golgi apparatus which filled the entire cytoplasm. Hydropically swollen nerve endings with disappearance of vesicles were frequently found. In later stages, degenerative or necrotic cells were scattered in the acini, and the size and the structure of the remaining acinar cells became gradually similar to those of non-treated glands. The morphological changes seen in the enlarged SMG induced by single amputation of the lower incisor teeth in rat were similar in many ways to those of sialadenosis induced experimentally by active sympathomimetic drugs.

Amputation, Surgical↗
PubMed1986

Inferior vena cava thrombus after retroperitoneal lymphadenectomy for testicular tumor.

A rare case of a thrombus in the inferior vena cava (IVC) after retroperitoneal lymphadenectomy for a testicular tumor is reported. A computed tomograph performed after the operation incidentally showed a filling defect in the IVC. However, it was impossible to decide whether the defect was due to an ordinary or a neoplastic thrombus. For this reason, a thrombectomy was performed, and postoperatively it was diagnosed as an ordinary thrombus. The cause of thrombi found only in the IVC is reviewed and the indication for thrombectomy is discussed.

Adult↗
PubMed1986

Age-related changes in right and left ventricular function in tetralogy of Fallot.

Age-related changes in right (RV) and left (LV) ventricular myocardium in tetralogy of Fallot (TF) are analyzed with regard to pre- and postoperative ventricular function. In RV, preoperative function was better in patients under 4 years of age in terms of ejection fraction and compliance, but no significant change was seen in LV function. Postoperatively, patients who underwent corrective surgery at age less than 4 years showed no significant difference compared to those at operative age above 4 years in terms of RV and LV functions at rest. However, stress tests for RV by isoproterenol and LV using methoxamine revealed some masked ventricular dysfunction in both ventricles in the older groups. The relationships between these functional abnormalities and previously described histological changes of right and left ventricular myocardium in TF are discussed.

Age Factors↗
PubMed1986

Ventricular volume of single ventricle with or without palliation and after corrective surgery--concept of septation procedure.

Ventricular volume measurements of single ventricle were carried out in 20 patients with or without palliation and in 2 after total correction. In the former 20 patients, 6 had a single left ventricle and 14 a single right ventricle, anatomically. Two having total correction were associated with undivided ventricle. In the 20 patients with or without palliation, ventricular end-diastolic volume ranged from 64 to 206 (115 +/- 42) percent of the sum of the normal left and right ventricular volumes. Ejection fraction of single ventricle ranged from 0.40 to 0.64 (0.55 +/- 0.06). There was no significant difference in ventricular volume and ejection fraction between patients with a single left and right ventricle. There was high correlation of ventricular volume with pulmonary to systemic blood flow ratio (r = 0.66, p less than 0.005). This indicates that systemic-to-pulmonary shunt should increase ventricular volume of single ventricle. In two patients after total correction, total ventricular volume was 136 and 166% of the sum of the normal left and right ventricular volumes. Total ejection fraction was 0.55 and 0.33 in the first and second patient, respectively. The prosthetic ventricular septum bulged toward the right ventricle during systole and this shift made the left ventricular volume increase and ejection fraction decrease. Right-to-left ventricular volume ratio at end-diastole was 0.74 and 0.67 in the first and second patient, respectively. These results suggest that 1) larger ventricular volume than the sum of the normal left and right ventricular volumes would be required for septation of single ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)

Heart Septum↗