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Biomedical subjects

G L Hallman

Publications and source records attributed to G L Hallman.

At least 37 records · Page 2Linked to original sources
PubMed1985

Valve failure with the Ionescu-Shiley bovine pericardial bioprosthesis: analysis of 2680 patients.

Early reports on the excellent hemodynamic function and low thromboembolic rates of the Ionescu-Shiley bovine pericardial bioprosthetic valve (BPV) encouraged us to use it as our choice for valve replacement in 2680 patients from 1978 through 1983. Analysis of these patients at 5-year follow-up (mean 21.6 months) demonstrated the following important trends. Despite anticoagulation therapy in 48%, thromboembolism occurred in 88 patients for a linearized rate of 1.87% emboli per patient-year and was not time-related. The highest incidence of thromboembolism was in mitral valve replacement (MVR) (2.76% per patient-year). The actuarial freedom from reoperation resulting from valve failure at 5 years was 82% in aortic valve replacement (AVR), 87.1% in MVR, and 92.6% in AVR/MVR. The most distressing causes for reoperation were valve calcification (33 patients, 0.68% per patient-year) and leaflet disruption (11 patients, 0.23% per patient-year). Valve calcification was related to age, small valve size, and AVR position and increased with time, especially at the 4- to 5-year intervals. In patients under 30 years of age, calcification occurred in 18.7% at a mean time of 40.8 months in AVR and in 8.2% at 44 months in MVR, for an overall rate of 11.6%. Over the age of 30 years, it occurred in 14 patients (0.6%) at a mean time of 44 months. Leaflet disruption was not related to age and occurred later in AVR (50 to 58 months) than MVR (1.5 to 61 months). Events increased with time (mean range 37 to 58 months). Because of calcification and leaflet disruption, valve failure causing reoperation has increased significantly at the 4- to 5-year intervals even when valve replacement in patients under 30 years of age is excluded. If this trend continues, the valve failure rate will be exceedingly high on further follow-up. Thus we have limited the use of the BPV to a selected group of patients in whom valve longevity is less important than effective orifice size, thromboembolic rate, and freedom from anticoagulation.

Actuarial Analysis↗
PubMed1984

False iliac aneurysms.

Of 2,389 aortoiliac, femoral bypasses performed from 1971 to 1983 at our institution, 182 pseudoaneurysms were observed; of these, only 17 were false anastomotic iliac aneurysms (9.4%) among 13 patients. The mode of presentation varied from pain or swelling in the lower quadrant of the abdomen, or a combination of both, to acute rupture of the false aneurysm in the abdomen. The surgical management of patients with false aneurysms was the same for those with true aneurysms. Three patients died because of complications during the early postoperative period. Histologic studies secured during operation provided evidence supporting our belief that the main causes of false iliac aneurysms are primarily a weakened host arterial wall and secondarily the inadequacy of suture material used.

Journal Article↗
PubMed1984

Rupture of the thoracic aorta: emergency treatment and management of chronic aneurysms.

Between 1957 and 1983, 58 patients were treated in our institution for traumatic rupture of the thoracic aorta. Seven patients had acute ruptures and 51 had traumatic aneurysms. Surgical correction of the lesion was obtained by means of left femoral artery bypass in 17 patients, femoral artery-femoral vein bypass in five patients, and external shunt in three patients. After 1975, simple aortic cross-clamping was used in 33 patients. There was one death 1 week after a procedure for ventricular fibrillation. Paraplegia occurred in two patients, and both cases were correlated with hypotensive episodes. From this experience and that of others, it was determined that an aortogram should be performed in all patients suspected of having highspeed deceleration trauma, and that such patients should undergo surgical repair as soon as possible after diagnosis.

Journal Article↗
PubMed1984

Interrupted aortic arch: brief review and summary of an eighteen-year experience.

Interrupted aortic arch (IAA) is an uncommon congenital anomaly representing approximately 1% of congenital heart disease. More than 97% of the cases also have associated cardiac anomalies complicating their treatment. Because the median age at death in untreated cases is 10 days, this condition usually occurs as a complicated neonatal surgical emergency. There are three types of IAA: Type A is interrupted distal to the left subclavian artery. Type B, which is the most common form, is interrupted between the left common carotid and the left subclavian arteries. Type C, which is the most uncommon type, is interrupted between the innominate and left common carotid arteries. Since the first patient with this congenital anomaly was treated at our institution in 1965, 39 patients have undergone surgical treatment. Two of these (4.6%) had no associated intracardiac lesions, and both survived bypass grafting without complications. There were 12 Type A (30%), 26 Type B (67%) and one Type C (3%). A variety of individualized techniques were used to repair the defects. The three basic techniques were (1) direct aortic to aortic anastomosis bridging the gap, (2) "turndown" or "turnup" of one of the arch vessels to the aorta across the gap, or (3) bypass of the interruption with graft material. Because aortic arch and associated cardiac anomalies represent a neonatal surgical emergency, our therapeutic plan consists of treatment for biventricular failure and PGE(1) infusion to maintain ductal patency, and surgical correction as soon as feasible.

Journal Article↗
PubMed1984

Coronary artery bypass for unsuccessful percutaneous transluminal coronary angioplasty.

Of 518 consecutive patients undergoing percutaneous transluminal coronary angioplasty for 571 coronary lesions, 184 eventually underwent coronary artery bypass because of angioplasty failure. Delayed coronary bypass (1 week to 19 months) was done in 27 patients with no deaths. Immediate bypass was done in 87 patients with two deaths, both of which were caused by further dissection of the artery after angioplasty. Urgent bypass was required in 63 patients who were in unstable condition because of ischemia on the electrocardiogram (52 patients), unrelieved angina (57 patients), or hypotension (13 patients). There was one death in this group. In the remaining seven patients, urgent coronary bypass was done because of cardiac arrest (three deaths). Myocardial complications occurred in 23 of the 70 unstable patients, including the seven patients with cardiac arrest. There were only eight completed myocardial infarctions in the 70 unstable patients and a completed myocardial infarction rate of 11 of 184 (6.0%) overall. In the 10 patients in whom extracorporeal circulation was established within 25 minutes of myocardial insult, mortality and myocardial complications were completely avoided. The remaining patients in the urgent group were placed on cardiopulmonary bypass within 26 to 300 minutes (mean 82 minutes). Operative mortality (3.3%), completed myocardial infarction (6.0%), myocardial infarction in unstable patients (32.9%), postoperative hemorrhage (5.0%), and sternal problems (2.8%) were all significantly different from those in 3,500 consecutive coronary bypasses not following angioplasty, that were done in 1982.

Adult↗
PubMed1984

Long-term results of direct vertebral artery operations.

Arteriosclerotic occlusive disease of the vertebral arteries is common; however, vertebral artery operations are performed infrequently. From 1971 through 1983 more than 3000 cerebrovascular operations were performed; only 40 of these were direct vertebral artery operations. There were 22 women and 18 men, varying in age from 44 to 80 years (mean 61.6 years). Symptoms included dizziness or vertigo in 29 patients (73%), transient ischemic attacks in 17 (43%), syncope in eight (20%), and previous stroke in 14 (35%). Operative procedures were directed toward establishing normal antegrade vertebral flow by reimplantation (21 patients), patch graft (15 patients), or grafts (three patients). Two patients underwent bilateral procedures. There were no operative deaths. All except two patients (95%) were available for follow-up at 1 to 12 years (mean follow-up 7.75 years). There were eight late deaths from 1 to 9 years, with a 12-year actuarial survival rate of 75.8%. The eight patients who died were known to be without symptoms before death. Of the 30 survivors available for follow-up, 21 remained without symptoms, seven patients showed no improvement, two patients who had no symptoms had recurrence at 4 and 5 years, and one patient without symptoms had a stroke at 7 years. In this select group of patients with severe disease, direct vertebral artery operations have resulted in significant long-term relief of symptoms and prevention of transient ischemic attacks and strokes.

Adult↗
PubMed1984

Cardiac tumors. Clinical spectrum and prognosis of lesions other than classical benign myxoma in 20 patients.

Between 1961 and 1983, 20 patients underwent operation at the Texas Heart Institute for primary tumors other than classical benign myxoma. Total follow-up was 70.7 patient years (mean 3.5 years). There were 10 adults and 10 children under 12 years of age. There were two operative deaths and four late deaths. All of the pediatric patients had benign lesions (five fibromas, five rhabdomyomas), and only one patient in this group died (during the operation). All operative survivors are alive between 0.9 and 18 years postoperatively, although in three cases excision was incomplete. Of the 10 adult patients, five had benign lesions; all were completely excised. In the other five adult patients, unresectable malignant tumors were found, and all four operative survivors died of metastatic disease within 8 months. Benign cardiac tumors in childhood have an excellent prognosis when completely excised and appear to have a good short-term prognosis even when excision is incomplete. Although prognosis for benign tumors in adults is good, malignant tumors are associated with very poor survival.

Adolescent↗
PubMed1983

Cor triatriatum: operative results in 25 patients.

Twenty-five patients with cor triatriatum underwent surgical correction at the Texas Heart Institute during a 21-year period from 1959 to 1980. Patients ranged in age from 4 months to 38 years. Diagnosis was established preoperatively in 14 patients (56%), at the time of operation for correction of associated lesions in 10 patients (40%), and during reoperation in 1 (4%). In the earlier part of this series, diagnosis was more common at the time of operation. Associated cardiovascular anomalies were present in 20 patients (80%), major anomalies in 14 others (56%). Simultaneous correction or palliation of associated lesions and total excision of the anomalous membrane were done in 18 patients utilizing temporary cardiopulmonary bypass. Cor triatriatum alone was repaired in 5 patients (20%) with the aid of extracorporeal circulation. Two patients underwent reoperation: 1 because of incomplete excision of the septum and the other because the condition had not been diagnosed during a first operation for correction of total anomalous pulmonary venous return. Excision of the membrane was accomplished utilizing the left atrium in 10 patients (40%), the right atrium in 12 (48%), or both in 3 (12%). Four patients (16%) died early after operation; all were infants who had severe associated cardiac anomalies. Among the 21 surviving patients, results were excellent in 20.

Adolescent↗
PubMed1981

Intracorporeal (abdominal) left ventricular assist devices or partial artificial hearts: A five-year clinical experience.

An intracorporeal (abdominal) left ventricular assist device (ALVAD) or partial artificial heart was designed, developed, extensively tested in vitro and in vivo, and subsequently approved for controlled clinical trials in institutions. The ALVAD is pneumatically actuated, synchronously or asynchronously, with an external console and is interposed between the apex of the left ventricle and infrarenal abdominal aorta. The implantation techniques are straightforward and replicable. The ALVAD was used in weaning from cardiopulmonary bypass to support the circulation in cardiogenic shock after infarction and as a bridge to cardiac transplantation. It was found that the profoundly depressed human left (and right) ventricles initially incapable of ejection can recover if totally supported with this device. This experience strongly suggests that ALVADs should be used early in instances of intra-aortic balloon pump inadequacy.

Adult↗
PubMed1981

Comparison of resection versus patch aortoplasty for repair of coarctation in infants and children.

To evaluate two surgical techniques of treatment for coarctation of the aorta in infants and children, we retrospectively compared our long-term experience with resection and end-to-end anastomosis ("resection") vs Dacron patch aortoplasty in patients operated upon when younger than 16 years of age. Since 1967, 184 patients underwent either resection (n = 96) or patch aortoplasty (n = 88). These groups were comparable in terms of preoperative systolic blood pressure, systolic pressure gradient across the coarctation, the year of operation, age and weight at operation, prevalence of associated cardiovascular defects, and duration of postoperative clinical follow-up (1-12.3 years, median 4.3 years). There was no statistically significant difference in operative mortality between surgical groups. Among 104 patients with follow-up longer than 1 year, there was no statistically significant difference between the two operations in the appearance of a residual gradient greater than 10 mm Hg, but for both groups this degree of residual gradient was more frequent in infants (22 of 43, 51%) than in older children (18 of 61, 31%; p less than 0.025). Late postoperative systolic hypertension was noted in 20 of 104 patients (19%), divided equally between the two operative groups. Most late hypertensive patients (13 of 20, 65%) also had residual coarctation; otherwise, the occurrence of postoperative hypertension was not influenced by the type of repair or age at repair. We conclude that resection and patch aortoplasty are equivalent operations for coarctation of the aorta in infants and children, and that long-term relief of gradient is related to age at operation rather than to technique of repair.

Adolescent↗
PubMed1980

Hemodynamic observations in patients with left ventricle to aorta conduit.

Fourteen patients who had a left ventricular apex to abdominal aorta composite conduit implanted for relief of severe left ventricular outflow tract obstruction were studied at cardiac catheterization 7 days to 19 months postoperatively (median 12 days). Analysis of pressure, angiographic and blood flow velocity data showed the following: (1) The left ventricle to aorta pressure gradients were reduced from an average preoperative value of 100.6 mmHg (range 54 to 140) to an average of 22.1 mm Hg (range 0 to 60) postoperatively; (2) postoperative left ventricular end-diastolic volume averaged 87.5 percent of normal (range 51 to 146); (3) cardiac index and ejection fraction were normal postoperatively in all but one patient. Left ventricular and aortic angiography revealed blood flow through both the ascending aorta and conduit in all patients and retrograde flow of blood from the conduit to the aortic arch in four. An average of 36 percent (range 16 to 50) of the left ventricular output was ejected through the conduit. It appears that this operation is effective in relieving severe and otherwise inoperable left ventricular outflow tract obstruction and in preserving or improving left ventricular function and aortic hemodynamics.

Adolescent↗
PubMed1980

Taussig-Bing anomaly: total repair with closure of ventricular septal defect through the pulmonary artery.

Total surgical repair of a Taussig-Bing malformation in an 8-year-old boy was accomplished successfully after previous palliative procedures. The child had undergone a Rashkind septostomy when he was 10 days old, banding of the pulmonary artery and division of a patent ductus arteriosus when he was 2 weeks old, and a Blalock-Hanlon septectomy when he was 1 year old. Complete repair involved patching the ventricular septal defect (VSD), debanding and patching the pulmonary artery, and rerouting the venous return by performing a Mustard procedure. Because of its high location, the VSD could not be reached properly through the tricuspid valve and was approached through the pulmonary arteriotomy. Excellent exposure was obtained by retracting the pulmonary valve, and patch closure of the defect was achieved without difficulties. We believe this approach to the VSD is preferable because no incision is necessary in the right ventricle. This is important since the right ventricle becomes the systemic ventricle after the Mustard operation.

Child↗
PubMed1979

Management of surgical complete atrioventricular block in children.

Because there is disagreement concerning the efficacy of and indication for permanent pacemaker implantation in children with postoperative complete (third degree) atrioventricular (A-V) block, experience in the management of this problem at one institution was reviewed. Thirty-four patients with postoperative complete atrioventricular block were identified. They ranged in age from 4 months to 22 years and in weight from 4 to 60 kg and were evaluated from 1 month to 20 years postoperatively. Complete A-V block developed within 24 hours of operation in 28 of the 34 patients. A permanent pacemaker was implanted in 13 of the 28. Death occurred in 4 of these 13 patients and in 5 of the remaining 15 patients who did not have an artificial permanent pacemaker. Complete A-V block developed later than 1 day (2 days to 4 months) postoperatively in 6 of the 34 patients; all 6 of these patients survived, and only 3 required permanent pacemaker implantation. Intracardiac electrophysiologic studies were performed by 14 of the 34 patients. The site of complete block was above the His bundle in 5, within the His bundle in 2, and below the His bundle in 4; it was undetermined in 3. The results of intracardiac electrophysiologic studies are important in delineating the natural history of surgically induced complete A-V block and in the clinical management of this lesion. Permanent pacemaker implantation is indicated if complete A-V block persists longer than 2 weeks postoperatively and if the site of the block is within or below the bundle of His.

Adolescent↗
PubMed1977

Aneurysm of pericardial right ventricular outflow tract patches.

Among 1,022 patients who underwent repair of tetralogy of Fallot, 252 received a pericardial patch of the right ventricular outflow tract; of these, 10 subsequently developed an aneurysm of the right ventricular outflow tract. Cardiac catheterization and angiography revealed moderate pulmonary insufficiency in all patients, a residual pressure gradient in the right ventricular outflow tract in 7, and a residual ventricular septal defect in 2 patients. Reoperation was indicated in 8 patients because of progressive distention of the aneurysm, residual infundibular or pulmonary artery stenosis, and recurrent ventricular septal defect. Reconstruction of the right ventricular outflow tract was accomplished by resection of the aneurysm and insertion of a woven Dacron patch in 5 patients, primary suture of the pulmonary artery in 2, and implantation of a woven Dacron conduit containing a Björk-Shiley cardiac valve prosthesis in 1 patient. There were no early or late deaths. When reconstruction of the right ventricular outflow tract is necessary, we recommend a woven Dacron patch because pericardium may form an aneurysm.

Cardiac Catheterization↗
PubMed1977

Reoperation following direct myocardial revascularization.

Among the 5507 patients who underwent aortocoronary bypass between October 1969 and June 1975, 41 patients (0.007%) developed recurrent angina and required reoperation. The factors necessitating reoperation were graft thrombosis in 10 patients (24%), progression of disease in 12 (29%), graft thrombosis and critical unbypassed lesions in one (2.4%), graft failure and progression of disease in in 12 (29%), graft failure and critical unbypassed lesions in four (10%), and all three factors in two patients (4.8%). Among 10 patients with 50% lesions present but not bypassed at the initial operation, nine of these lesions progressed to significant stenosis and in five patients this was the sole reason for reoperation. At the second operation, total revascularization was achieved in 32 patients (78%). One patient (2%) experienced a perioperative myocardial infarction and one patient (2%) died. This study emphasizes the importance of "complete" revascularization at initial operation, the concept that arteries with 50% obstruction should be routinely bypassed, and the conclusion that risks of reoperation are comparable with those of initial aortocoronary bypass, but that long-term relief of angina is less favorable.

Adult↗