Biomedical subjects

K Momma

Publications and source records attributed to K Momma.

206 records · Page 12Linked to original sources

PubMedDate not supplied

Cardiovascular and pulmonary effects of betamethasone during midtrimester on fetal rats.

In order to elucidate the effects of corticosteroids on fetal hearts during midtrimester, pregnant rats were injected with a daily dose of betamethasone (1 mg/kg) from the 12th day through the 17th day of pregnancy. The fetal cardiovascular and pulmonary systems were studied on the 21st day of pregnancy (term). The treated fetuses showed the following signs of hydrops fetalis: retarded growth, pale, edematous skin, and decreased movement. The thymus and lung displayed prominent hypoplasia. The morphometry of the treated fetuses revealed: decreased right ventricle mass by 37% and decreased left ventricle mass by 29%. We concluded betamethasone had a significant effect on the developing fetal cardiovascular system, inducing hydrops fetalis. Additionally, beta-methasone caused hypoplasia of the thymus and lung.

Animals↗

PubMedDate not supplied

Fetal cardiovascular morphology of interrupted aortic arch type B in rats.

Interrupted aortic arch type B associated with ventricular septal defect (n = 17) or atrioventricular septal defect (n = 2) was induced in 19 of 300 fetuses by maternal administration of bis-diamine on the 9th and 10th day of pregnancy. After rapid whole-body freezing on the 21st day, the fetuses were studied by means of serial cross-sectional photographs of the frozen thorax. In fetuses with interrupted aortic arch, the ascending aorta was small, and the ratio of its diameter to the diameter of the pulmonary trunk was 0.64 +/- 0.03 (mean +/- SEM) in contrast to 0.96 +/- 0.02 in the control. The aortic arch was interrupted distal to the left common carotid artery (type B of Cerolia and Patton) in all cases.

Abnormalities, Drug-Induced↗

PubMedDate not supplied

In situ morphology of fetal aortic isthmus following ductal constriction in rats.

To clarify the effect of experimentally increased blood flow to the aortic isthmus, in situ cross-sectional morphology of the aortic isthmus and the juxta-ductal descending aorta was studied in fetal rats. Indomethacin (10 mg/kg) was administered to 10 near-term pregnant rats, and fetuses were studied 4 and 24 h later with cesarean section, rapid whole-body freezing, sectioning on a freezing microtome in a plane perpendicular to the aortic isthmus, and photographing cross-sections. Fetuses without treatment served as controls. The ductus was constricted and its cross-sectional area was 12 +/- 3% (mean +/- SEM, % of control; p < 0.05 vs. control) at 4 and 24 h. The aortic isthmus was enlarged and the cross-sectional area was 146 +/- 5% at 24 h in response to the increased flow. These results support the concept that the size of the fetal aortic isthmus can change rapidly depending on the flow in late gestation.

Animals↗

PubMedDate not supplied

Fetal in situ cardiovascular and pulmonary morphology of vascular ring due to left aortic arch and right ductus arteriosus in rats.

We studied 17 fetal rats with vascular ring composed of the left aortic arch and right ductus arteriosus and 7 fetal rats with the mirror-image arrangement. The vascular ring of this type was induced by administration of bis-diamine (200 mg) on the 9th and 10th day of pregnancy in rats. In the most severe case, the esophagus and trachea were compressed completely and no inner space was left, and localized and diffuse tracheal stenosis was prominent. The fetal lung mass was increased as the stenosis of the ring was severe. The thoracic descending aorta was positioned in the left side, and was contrasted with the clinically observed right descending aorta in this postnatal anomaly. Thus we are reporting two new findings in the fetal vascular ring with the left aortic arch and the right ductus arteriosus: increased lung mass and left descending aorta in a fetal animal model.

Animals↗

PubMedDate not supplied

[Caudal-angle aortography. Its usefulness for defining the coronary anatomy in cases of transposition of the great vessels].

With the purpose of obtaining an accurate definition of coronary arteries anatomy in complete transposition of the great arteries (concordant atrio-ventricular connection and discordant ventriculo-arterial connection), we performed a new angiographic technique in 14 patients with d-transposition of the great arteries and 1 patient with double-outlet right ventricle. This technique consists of using a balloon catheter with the frontal X ray tube cine-angiographic camera in caudal angulation (about 45 degrees), with balloon occlusion of the ascending aorta during the injection of the contrast medium. The results were compared with echocardiograms and surgical results. In all our cases, except 2, the technique gave us a very clear definition of the coronary anatomy and we were able to define the origin and course of the coronary arteries without difficulty. In the most common coronary artery pattern, the left coronary artery arose from sinus #1 (left aortic sinus) and gave origin to the anterior descending and left circumflex arteries, while the right coronary artery arose from aortic sinus #2 (right aortic sinus). In our series, the coronary arteries always originated from one or both facing sinuses of the aorta and the angiographic correlation with the surgical reports was accurate in all the cases. The anatomical and angiographic findings of this series are discussed. In conclusion, we find the aortogram with caudal angulation a very useful technique to improve the visualization of coronary anatomy in d-transposition of the great arteries, which has surgical significance in those cases which are candidates for anatomical correction.

Aortography↗

PubMedDate not supplied

Hemolysis due to aortic insufficiency following closure of ventricular septal defect.

A two-year-old girl with ventricular septal defect (VSD) developed a severe degree of intravascular hemolysis following VSD closure. The cause of hemolysis was considered to be due to the aortic insufficiency (AI) jet against the VSD patch. The patient was reoperated on the seventh post-operative day. There was a small hole on the right coronary cusp, which was closed by five interrupted sutures. However, a third operation was performed on the following day because of the reappearance of AI. The use of pericardial flap to cover the whole right coronary cusp resulted in disappearance of hemolysis. The patient was discharged in a satisfactory condition.

Anemia, Hemolytic↗

PubMedDate not supplied

Pseudotumor of the heart: subepicardial hematoma of the right atrium.

A 28-year-old man with a huge subepicardial hematoma of the right atrium, which is so rare that a review of the literature has failed to disclose similar case, is reported. Suspecting of rhabdomyoma, we excised free wall of the right atrium and a part of lateral wall of the superior vena cava. The excised part was reconstructed with expanded polytetrafluoroethylene (Gore tex). This synthetic material has a few merit and application of this one to the reconstruction in the venous system seems more promising. He was discharged with a regular sinus rhythm, normal heart size three months after the operation. The histologic examination of the excised material revealed amorphous blood clots and chronic granulation tissue containing hemosiderin-cells. The cause of the hematoma was not clarified even by microscopic examination.

Adult↗

PubMedDate not supplied

[Natural history of atrial septal defect with pulmonary hypertension: follow-up of medically treated patients over 16 years of age].

The clinical course and prognosis of 20 consecutive patients aged over 16 years with atrial septal defect and pulmonary hypertension were analyzed. All patients, six men and 14 women, underwent cardiac catheterization at an average age of 43 years and received medical treatment. All patients with the ostium secundum type had a systolic pulmonary arterial pressure of 87 +/- 18 mmHg (mean +/- SD) and a pulmonary arteriolar resistance of 17 +/- 11 U.m2. At a mean follow-up period of 8 years, nine patients had died of cardiac causes at a mean age of 51 years, 10 were alive, and one was lost to follow-up. Five out of 13 patients with a pulmonary arteriolar resistance of 14 U.m2 or more had died of progression of the pulmonary vascular obstructive disease. Two of the seven patients with a pulmonary arteriolar resistance less than 13 U.m2 had died of pulmonary vascular obstructive disease and another two died of congestive heart failure. Although 25% of the patients had become symptomatic before 20 years of age, the diagnosis of atrial septal defect was not made until a mean age of 39 years. Eighteen patients became more severely symptomatic, but the time until the development of the symptoms varied. The mean age of patients in the New York Heart Association class I, II, III-IV were 27, 38, and 48 years of age, respectively. The percent survivals at 50 and 60 years of age were 77% and 54%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗