Search PubMed⌕ Search

Biomedical subjects

K Momma

Publications and source records attributed to K Momma.

At least 163 records · Page 9Linked to original sources
PubMed1983

Significance of systemic vascular resistance in determining the hemodynamic effects of hydralazine on large ventricular septal defects.

The hemodynamic effects of hydralazine were studied in 17 infants and young children with ventricular septal defects to clarify the significance of systemic vascular resistance (SVR) in determining these effects. Patients with peak pulmonary arterial pressures greater than 75% of systemic pressure were placed in group I, which was further divided into group Ia (n = 6), consisting of those with a control SVR of 20 U.m2 or higher, and group Ib (n = 8), consisting of those with a lower SVR. Group II consisted of three patients with lower pulmonary arterial pressures. Intravenous injection of hydralazine (0.3 mg/kg) reduced SVR in all but two patients. The magnitude of reduction correlated with prehydralazine (control) SVR (r = .66, p less than .01). Systemic blood flow (Qs) increased from 3.7 +/- 0.7 to 5.0 +/- 0.8 l/min/m2 (p less than .005). The mean systemic arterial pressure for all patients decreased from 69 +/- 2 to 65 +/- 2 mm Hg (p less than .01) and the mean pulmonary arterial pressure decreased from the control value by 9 +/- 4% (p less than .01) in group I and by 17 +/- 1% in group II. Pulmonary blood flow (Qp) did not change significantly in either group. The Qp/Qs ratio was reduced from 3.6 +/- 0.4 to 2.4 +/- 0.2 (p less than .02) in group Ia. In sharp contrast, however, it increased from 2.6 +/- 0.3 to 3.3 +/- 0.5 (p = .06) in group Ib. The posthydralazine Qp/Qs ratio, expressed as percent of the control value, inversely correlated with the control SVR (r = -.61, p = .02) in group I. The response was not different in the group II patients. Thus, we conclude that control SVR is important for prediction of the hemodynamic effects of afterload reduction by hydralazine in infants and young children with large ventricular septal defects, and that this drug may be beneficial in patients with high control SVRs since a high SVR brings about a decrease in the Qp/Qs ratio.

Blood Circulation↗
PubMed1983

Sudden death of the young with cardiovascular diseases.

Sudden death due to cardiovascular diseases was studied in 142 children who died suddenly during the period from 1969 to 1981. The age-distribution analysis showed that death occurred most frequently in infancy and it decreased with age. The subjects were divided into 7 groups, of which the hypoxemic group, consisting of 45 cases (32%), was the largest, followed by the congestive heart failure (CHF) group (33 cases, 23%), the primary endomyocardial disease (PMD)-coronary heart disease (CorHD) group (21 cases, 15%), the postoperative group (18 cases, 13%), the pulmonary vascular obstruction group (17 cases, 12%), the arrhythmia group of 3 cases and the miscellaneous group of the remaining cases. In the hypoxemic, CHF and arrhythmia groups, the majority of the cases were infants, while in the other groups the cases were distributed among all age groups. The relative incidence of each group showed that non-surgical and inoperable cases and postoperative cases increased with age and this increase has occurred in the last few years. This change has been brought about by the recent advances in medical and surgical treatments for infants with congenital heart diseases. It is hoped that in the future the number of cases which are too late for treatment will decrease further.

Adolescent↗
PubMed1983

Constriction of fetal ductus arteriosus by nonsteroidal antiinflammatory drugs.

Transplacental fetal ductal constriction was studied for 24 NSAIDs in full-term pregnant rats. All 16 acidic NSAIDs constricted the fetal ductus, but considerable differences in the grade of effect were noticed with the clinical doses of each NSAID. Six of the eight basic NSAIDs did not constrict the fetal ductus. It is concluded that acidic NSAIDs should not be administered to pregnant women. However, it may be established in the future that some basic NSAIDs can be administered safely.

Animals↗
PubMed1982

Transarterial pulmonary venous wedge arteriography in pulmonary atresia, ventricular septal defect, and intact atrial septum.

Transarterial pulmonary venous wedge arteriography was performed in four cases of pulmonary atresia (PA), ventricular septal defect (VSD), and intact atrial septum. In two cases, only the left pulmonary artery was visualized by selective injection to the patent ductus arteriosus (PDA) or Blalock-Taussig anastomosis (B-T shunt), and the right pulmonary artery was opacified by transarterial retrograde pulmonary arteriography. In two other cases, with nonfunctioning B-T shunt, the pulmonary artery was not opacified by either aortography nor by injection into the B-T shunt. Transarterial pulmonary vein wedge arteriography visualized a confluent pulmonary artery. Transarterial pulmonary vein wedge arteriography was a useful and safe procedure for opacifying the pulmonary artery that could not be visualized antegradely in VSD, PA, and intact atrial septum.

Adolescent↗
PubMed1982

Angiocardiographic study of coarctation of the aorta--morphology and morphogenesis.

Angiocardiographic morphology and associated cardiac anomalies of the coarctation of the aorta (COA) were analysed in the light of recently advanced theory of its morphogenesis. Analysis of 154 clinical cases of COA revealed the presence of associated cardiac anomalies which could obstruct fetal blood flow to the ascending aorta in many cases. Systolic left ventricular outflow tract was significantly narrow in cases of ventricular septal defect (VSD) associated with COA in comparison with the isolated VSD (p less than 0.01). Good quality aortograms obtained from 41 cases of COA were analysed. Ages ranged from one month to 20 years and major cardiac anomalies were associated in 25 cases. Age-matched 37 cases were studied as the controls. In COA, the isthmus was narrower than the controls in 88% of the cases, and in the remaining it was low in the normal range. Severely hypoplastic isthmus in early infancy became the adult type after 5 years in one of the 4 cases which had repeated aortography. Localized stenosis at the distal end of isthmus was present in 89%, and absent in 11% (4 cases). In these 4, isthmal narrowing was associated with major intracardiac anomalies, large patent ductus arteriosus (PDA) and pulmonary hypertension (PH). The anterior ostium to the descending aorta was obstructed by constricted ductus arteriosus (PDA) and pulmonary hypertension (PH). The anterior ostium to the descending aorta was obstructed by constricted ductus arteriosus in some infants with COA. These angiographic findings are compatible with the following working hypothesis: ischemic hypoplasia results from prenatal decrease of blood flow to the ascending aorta, and localized stenosis is related to abnormal distribution of the ductal tissue to the descending aorta and post-natal constriction of the ductus arteriosus. In 3 infants COA was associated with persistent fifth aortic arch.

Adolescent↗
PubMed1981

Constriction of the fetal ductus arteriosus by glucocorticoid hormones.

Hydrocortisone, prednisolone, and betamethasone were injected into a rat that was 21 days pregnant, and the fetal ductus arteriosus was studied using the rapid whole-body freezing technique. All these glucocorticoids constricted the fetal ductus arteriosus in a dose-dependent relationship. Fetal ductal constriction was maximum 1 to 4 hr after injection and was significantly more prominent in premature fetuses than in mature ones.

Animals↗
PubMed1981

Natural and post-operative history of pulmonary vascular obstruction associated with ventricular septal defect.

The natural history of pulmonary vascular obstruction in VSD associated with PH was studied by measuring PVR before and after injection of tolazoline 1 mg/kg. Organic pulmonary vascular obstruction (PVO) was minimal in infancy, but increased linearly progressively with advancing age, and average rate of increase in PVR after tolazoline was 1 unit.m2/year. The rate of increase in PVR after tolazoline in Eisenmenger complex was variable and ranged between 0.7 to 4 unit.m2/year in most cases. Analysis of 7 cases of post-operative late death due to PVO revealed that usually these cases were over 5 years of age at operation, and pre-operative PVR was more than 12 unit.m2. Reduction of PVR was confirmed post-operatively in most of these cases whose pre-operative PVR before and after tolazoline were les than 8 unit.m2 and 7 unit.m2 respectively. Early surgical repair is indicated in VSD and PH to prevent progress of PVO.

Adolescent↗
PubMed1981

[Two-dimensional echocardiographic findings of a right ventricular diverticulum: a case report (author's transl)].

A 11-month-old boy with a right ventricular diverticulum was reported. To our knowledge, this is the 18th case in the literature and the first case observed by two-dimensional echocardiography. Using our systematic two-dimensional echocardiographic approach, the three dimensional structure of this anomaly was reconstructed correctly. On the short-axis view of the ventricle, an abnormal septal echo was revealed in the right anterior region of the interventricular septum, forming an another cavity from the right ventricle, and was observed to have proper own motion by real-time two-dimensional echocardiography. From apical four chamber view, the abnormal cavity was detected on the right side of the small right ventricle. By contrast echocardiography, a contrast echo appears in the right ventricle and then in the abnormal cavity. The diagnosis was confirmed by cardiac catheterization, angiography and operation.

Echocardiography↗
PubMed1980

Long-term follow-up of artificial valves in patients under 15 years old.

Forty-nine artificial cardiac valves implanted in 44 patients less than 15 years old were reviewed. Out of 49 valves, 16 were mechanical and 33 were xenografts. Average follow-up was 2 years 5 months. Marked valvular stenosis developed in 11 out of the 33 xenografts, an incidence of 15% per patient-year. In patients with a xenograft valve, the incidence of sepsis was found to be 4% per patient-year and brain accidents, 4% per patient-year. In patients with mechanical valves, the incidence of stenosis was only 2% per patient-year and brain accidents, 2% per patient-year. There was no sepsis. From these follow-up results, mechanical valves seem to be superior to xenografts when used in patients less than 15 years old.

Adolescent↗
PubMed1980

Dilatation of the ductus arteriosus by prostaglandins and prostaglandin's precursors.

We studied the effects of prostaglandins and their precursors in animal models. Rabbit ductus arteriosus constricted rapidly after delivery. PGE1, and PGE2, and arachidonic acid injected SC dilated the ductus over 60 min. Orogastrically administered PGE2 dilated the ductus for 3 hr. PGF2a and arachidonic acid showed weak ductus-dilating effects. Response of the ductus to PGE1 was most prominent in the first hr after birth. Pretreatment with indomethacin blocked the ductus-dilating effect of arachidonic acid.

Age Factors↗