Search PubMed⌕ Search

Biomedical subjects

J F Keane

Publications and source records attributed to J F Keane.

At least 109 records · Page 6Linked to original sources
PubMed1985

Monitoring of brainstem auditory evoked potentials during basilar artery occlusion in man.

Brainstem auditory evoked potentials (BAEP) were recorded during surgery as a monitor of brainstem function in three patients undergoing posterior fossa surgery for clipping of basilar aneurysms. In two patients, ligation of the basilar artery, and of a vertebral artery, was associated with deterioration in BAEP and resulted in postoperative brainstem dysfunction. In the third patient, postoperative transient neurological dysfunction occurred following temporary occlusion of the basilar artery and this correlated with intra- and postoperative changes in BAEP. BAEP monitoring is recommended where temporary or permanent occlusion of the vertebrobasilar system is planned.

Adult↗
PubMed1984

Primary surgical closure of ventricular septal defect in the first year of life: results in 128 infants.

Between January 1973 and July 1981, 128 patients less than 1 year of age with failure to thrive, congestive heart failure or pulmonary artery hypertension underwent primary repair of a ventricular septal defect. The hospital mortality rate was 7.8% (10 of 128), and the late mortality rate was 2.3% (3 of 128). Mortality was highest among younger infants with preexisting respiratory problems or a hemodynamically significant residual lesion postoperatively. Complications included a large residual shunt in eight (6.2%), transient neurologic problems in five (3.9%) and persistent complete heart block in three (2.3%). Lung biopsy specimens obtained from 49 patients showed pulmonary vascular abnormalities in all. Complete right bundle branch block developed in 74 (64%) and bifascicular block appeared in 11 (9%). Recatheterization in 70 patients (55%) showed normal pulmonary artery pressures in all but 2 patients with a large residual shunt. Complete closure of the defect had been achieved in 49 (70%), and a hemodynamically insignificant shunt remained in 19 (27%). Patients without significant hemodynamic residua were asymptomatic and tended to accelerate in growth after surgery.

Age Factors↗
PubMed1984

Vascular structure in lung tissue obtained at biopsy correlated with pulmonary hemodynamic findings after repair of congenital heart defects.

At the time of surgical repair, a lung biopsy was performed on patients with congenital heart defects who either had pulmonary hypertension or in whom it would be likely to develop if the lesion were not corrected. Pulmonary vascular changes, assessed morphometrically and also according to the classification of Heath and Edwards (Circulation 18: 533, 1958), were correlated with the postoperative pulmonary hemodynamic findings: mean pulmonary arterial pressure the day after correction and mean pulmonary arterial pressure and pulmonary vascular resistance measured 1 year later. On the first postoperative day, increased mean pulmonary arterial pressure was uncommon in patients with morphometric grade A or B (mild) biopsy findings and Heath-Edwards grade N (normal), and if it was present it was of a mild degree. Mean pulmonary arterial pressure was commonly elevated in those with grade B (severe) or C (mild or severe) and Heath-Edwards grade I biopsy results and was more frequently elevated in those with grade II findings. Moderate-to-severe elevation of mean pulmonary arterial pressure was invariable in patients with Heath-Edwards grade III changes regardless of the morphometric grade. One year after repair, mean pulmonary arterial pressure and/or pulmonary vascular resistance were normal in all patients whose conditions were corrected surgically before 9 months of age regardless of the severity of the pulmonary vascular changes. Values were normal in patients whose conditions were repaired surgically at 9 months of age or later who had grade A or B (mild) morphometric findings with any Heath-Edwards grade or grade B (severe) morphometric findings with Heath-Edwards grade I but were increased in half of the patients with grade B (severe) morphometric findings and Heath-Edwards grade II or with grade C (mild or severe) and Heath-Edwards grade I or II changes. Pulmonary arterial pressure and pulmonary vascular resistance were increased in all patients whose conditions were repaired after 2 years of age with grade C morphometric findings and to a severe degree if associated with Heath-Edwards grade III. Thus, although the Heath-Edwards grade can usually be used to identify patients at risk for pulmonary hypertension in the early postoperative period, both the morphometric and the Heath-Edwards grades as well as the age of the patient at the time of repair can be used to determine whether pulmonary arterial pressure and resistance eventually return to normal or remain elevated.

Autopsy↗
PubMed1983

Fixed subaortic stenosis in the young: medical and surgical course in 83 patients.

Eighty-three patients aged 11 months to 25 years were followed up a median of 6.1 years (range 8 days to 24 years) after diagnosis of fixed subaortic stenosis (SAS). Fourteen (17%) had significant noncardiac defects and 47 (57%) had additional cardiac malformations. The left ventricular (LV) outflow gradient increased in 25 of 26 patients catheterized more than once before surgery. Of 15 patients less than 12 years old with gradients less than or equal to 40 mm Hg, 10 ultimately underwent operation after developing severe obstruction; another has progressed to a gradient of 45 mm Hg at 6 years of age. Before surgery (at a median age of 12 years), 55% had aortic regurgitation (AR), which was usually mild. Infective endocarditis occurred in 12% of the group, with a frequency of 14.3 cases per 1,000 patient-years. Seventy-four patients were operated on, with 6 early (8%) and 7 late (9%) deaths. Twelve underwent reoperation to relieve residual obstruction. Surgery reduced gradients in patients with discrete SAS from 83 +/- 33 to 29 +/- 30 mm Hg, but in 6 patients with tunnel SAS the reduction was less satisfactory. AR was absent or mild in most patients postoperatively. When the gradient was reduced to less than 80 mm Hg, infective endocarditis did not occur unless there were other residual lesions. These data suggest that it is reasonable to resect discrete SAS in children less than 10 to 12 years old with LV outflow gradients greater than or equal to 30 mm Hg.

Adolescent↗
PubMed1983

Repeat aortic valvotomy in children.

The outcome in 13 children with congenital valvar aortic stenosis who underwent a repeat valvotomy for significant residual obstruction was reviewed. There was no hospital mortality (confidence limits 0% to 32%), while one late death (8%) occurred (confidence limits 1% to 57%) following the repeat procedure. Cardiac catheterization was performed in 10 patients (77%) following the second valvotomy (2 years, 7 months mean follow-up): (1) three children, all infants at initial valvotomy, had a peak systolic ejection gradient less than or equal to 40 mm Hg and only mild, at most, aortic regurgitation after the repeat operation; (2) the other seven had a peak systolic ejection gradient greater than 40 mm Hg or at least moderate aortic regurgitation, of whom two were infants at first valvotomy while the others ranged in age from 1 to 12 years at initial surgery. These results suggest that repeat aortic valvotomy may not significantly improve the hemodynamic status of those who did not require initial valvotomy early in life.

Adolescent↗
PubMed1983

Cineangiography of the perimembranous ventricular septal defect with left ventricular-right atrial shunt.

Nine cases are reported of perimembranous ventricular septal defect associated with left ventricular to right atrial shunting. Cineangiographic findings included an aneurysm of the membranous septum in all patients; two patients had obvious adherence of deformed tricuspid valve leaflets to the membranous septum. The location of the ventricular septal defect was confirmed at surgery or cardiac endoscopy in seven patients. In the presence of a perimembranous ventricular septal defect, left ventricular to right atrial shunting is usually the result of tricuspid valve abnormalities, including clefts or perforations of the septal leaflet, deformity or adherence of valve tissue to the margins of the septal defect and widening of the anteroseptal commissure. Biplane left ventriculography, using the long axial oblique and reciprocal right anterior oblique projections, may best demonstrate the pathologic anatomy, although the hepatoclavicular projection is a useful alternative, particularly when an atrioventricular canal defect is a diagnostic consideration.

Adolescent↗
PubMed1982

Radionuclide angiocardiographic assessment of pulmonary vascular reactivity in patients with left to right shunt and pulmonary hypertension.

Radionuclide angiocardiography was used to assess pulmonary vascular reactivity in eight patients (nine studies) with a large, relatively unrestrictive intracardiac defect and pulmonary arterial hypertension. Radionuclide angiocardiograms, using technetium-99m pertechnetate, were performed first with the patient breathing room air and then after 10 minutes of breathing a mixture containing 90 percent or more of oxygen. The pulmonary to systemic flow ratios obtained by gamma variate analysis of the radionuclide time-activity curves were compared with those calculated with the Fick principle at the time of cardiac catheterization. There was a good correlation between the two methods both in room air studies (r = 0.88) and in those obtained with 90 percent or more of oxygen (r = 0.94). All six studies (in five patients) with a reactive pulmonary vasculature (judged by a pulmonary vascular resistance at cardiac catheterization of less than 6 units/m2 with oxygen or after tolazoline) had a radionuclide pulmonary to systemic flow ratio of 3.0 or greater with oxygen. The three patients with a nonreactive pulmonary vasculature had a radionuclide pulmonary to systemic flow ratio of 2.3 or less with oxygen, a value that was unchanged from the room air value. These data suggest that radionuclide angiocardiography may be a useful, relatively noninvasive method of assessing pulmonary vascular reactivity in patients with a large, relatively unrestrictive intracardiac defect.

Angiocardiography↗
PubMed1982

Partial absence of the left pericardium. Diagnosis by two-dimensional echocardiography.

The partial absence of the left pericardium is an unusual cause of syncope and chest pain in children. The identification of this lesion is important because of potential herniation of the left side of the heart through the defect, resulting in fatal strangulation. Initial suspicion of the diagnosis should be raised by the typical cardiac contour on the chest roentgenogram. Two-dimensional echocardiography and cineangiography at cardiac catheterization are additional helpful studies in identifying partial pericardial defects.

Angina Pectoris↗
PubMed1982

Pediatric arterial catheterization using a 3.2 French catheter.

Retrograde arterial catheterization was performed in 105 infants and small children (median age 6 mo) using a 3.2 French pigtail catheter made of ultrathin walled white Teflon. Three catheter lengths were used, (40, 50, and 65 cm). Pressure recordings and ease of sampling were judged excellent in all. All 118 angiograms (60 ventricular) were performed without complication except for two episodes of external catheter rupture. Angiographic quality was rated excellent in 41%, good in 39%, fair in 18%, and poor in only 2%. Among the 81 patients in whom only this catheter was used percutaneously, pedal pulses were lost in 5%. Postcatheterization testing identified ranges of volume and flow-rate characteristics which included 8 ml at 15 ml/sec (40 cm length), at 11 ml/sec (50 cm length), and at 9 ml/sec (65 cm catheter). We conclude that this small catheter is relatively safe and satisfactory for retrograde catheterization of infants and small children.

Cardiac Catheterization↗
PubMed1982

Radionuclide angiocardiography in evaluation of patients after repair of transposition of the great arteries.

The ability of first pass radionuclide angiocardiography to detect and quantitate residual intracardiac shunts and systemic venous obstruction after repair of transposition of the great arteries was evaluated in 29 children. Information from radionuclide scans was compared with data obtained during cardiac catheterization. Three children had a residual right to left shunt detected with both methods. There was good agreement between radionuclide and catheterization quantitation of left to right shunt in the nine patients with a residual defect, five of whom had significant shunting. Nineteen patients with signs suggesting superior vena caval obstruction were evaluated with both radionuclide and catheterization methods. In eight, complete obstruction was detected with both techniques; in one additional patient, partial obstruction was found on catheterization only. One of six patients evaluated for possible inferior vena caval obstruction was identified with both techniques. In the group as a whole, information obtained with radionuclide angiography correlated well with cardiac catheterization data in evaluation of residual shunts and obstruction to systemic venous return.

Adolescent↗
PubMed1982

Repair of complete common atrioventricular canal in infancy.

Forty-three infants with common atrioventricular canal (CAVC) underwent repair before 24 months of age at Children's Hospital Medical Center, Boston, between Jan. 1, 1975, and June 30, 1980. From 1975 to 1977, the operative mortality was 62% (8/13); the late mortality was 7% (1/13). From 1978 to 1980, the operative mortality was 17% (5/30) and the late mortality, was 6% (2/30). Seventeen (63%) unselected patients of the 27 long-term survivors have undergone cardiac catheterization 10 to 19 months following the operation. Five (29%) had mitral regurgitation of either moderate (four) or severe (one) degree. One had a significant residual shunt. The pulmonary/systemic resistance ratio (Rp/Rs) remained the same or decreased after repair except in the patient with severe mitral regurgitation. Anatomic features which determine outcome of reparative procedures are (1) deficiency of atrioventricular valve tissue, (2) the presence of ventricular hypoplasia, (3) malalignment of the common atrioventricular valve (CAVV) with respect to the ventricles, (4) the presence of double-orifice mitral valve, (5) the presence of solitary left ventricular papillary muscle group, and, in our experience, (6) the presence of additional muscular ventricular septal defects (VSDs). Four of these six anatomic variables can now be evaluated preoperatively by axial angiography and subxiphoid two-dimensional echocardiography. However, the architecture of the CAVV is extremely variable, so that the development of a "uniform approach" to valve reconstruction is impossible; mitral dysfunction is likely to remain the major cause of operative mortality and long-term morbidity.

Cardiac Catheterization↗
PubMed1981

Preoperative angiocardiography in infants with tetrad of Fallot. Review of 36 cases.

Angiocardiograms in 36 infants with tetrad of Fallot were reviewed to determine which projections best displayed the anatomy. The occurrence of associated cardiovascular anomalies was also recorded. An additional ventricular septal defect was found in 14 percent (5 of 36), peripheral pulmonary stenoses in 30 percent (10 of 36) and surgically important coronary arterial abnormalities in 8 percent (3 of 36). This retrospective study indicated that optimal biplane angiocardiography should include: (1) right ventriculography in a sitting or hepatoclavicular view for demonstration of the right ventricular, infundibular, and pulmonary artery anatomy, (2) left ventriculography in the long axial oblique (cranially angled oblique) view for display of ventricular septal defects and coronary arteries, and (3) and aortogram at the valve level (oblique view) if coronary arteries are not well seen in the left ventricular study.

Angiocardiography↗