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Biomedical subjects

J M Pearl

Publications and source records attributed to J M Pearl.

At least 55 records · Page 3Linked to original sources
PubMed1992

Repair of conotruncal abnormalities with the use of the valved conduit: improved early and midterm results with the cryopreserved homograft.

Repair of complex cardiac lesions has been facilitated by the availability of valved conduits to reestablish right ventricular to pulmonary artery continuity. From 1977 to June 1991, 148 patients underwent repair with insertion of a conduit. Their mean age was 6.6 years (11 days to 45 years). The diagnosis was transposition of the great arteries with ventricular septal defect and left ventricular outflow tract obstruction in 51, truncus arteriosus in 36, pulmonary atresia with ventricular septal defect in 25, tetralogy of Fallot in 19, double-outlet right ventricle in 10, pulmonary atresia with intact ventricular septum in 6 and atrioventricular canal with pulmonary atresia in 1. A Dacron porcine-valved conduit was used in 37, a homograft conduit in 106 and a nonvalved conduit in 5. There were 13 early deaths overall (8.8%); 8 (22%) of the early deaths occurred in the 37 patients who received a Dacron graft, 4 (3.8%) occurred in the 106 patients who received a homograft and 1 occurred in a patient with a nonvalved Gore-Tex conduit. An additional patient underwent orthotopic heart transplantation in the early postoperative period. In 117 patients operated on from January 1985 to June 1991 the early mortality rate was 2.6% (3 of 117). Among 28 patients receiving a Dacron porcine-valved graft there were two late deaths (7.1%) after a mean follow-up interval of 93 months, and 8 patients required reoperation for conduit obstruction. Among 102 homograft recipients there were two late deaths (1.9%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Perfluorochemical reperfusion limits myocardial reperfusion injury after prolonged hypothermic global ischemia.

The ability of an oxygenated perfluorochemical (Fluosol) to limit myocardial reperfusion injury following global hypothermic ischemic insult was investigated. Neonatal piglet hearts were arrested with cold crystalloid cardioplegia and stored for 12 hours in 2 degrees C saline. Reperfusion was carried out using an isolated, blood-perfused, working heart preparation. Hearts were initially reperfused (10 minutes) with either whole blood (WB, n = 6), unmodified perfluorochemical (PFC, n = 8), or aspartate/glutamate-enriched perfluorochemical cardioplegia (PFC+, n = 6), prior to institution of whole blood perfusion, functional evaluation and left ventricular biopsy. A control group (C, n = 7) was evaluated without an intervening period of ischemia. At a left ventricular diastolic pressure of 9 mm Hg WB hearts developed a left-ventricular stroke work index (SWI) of 3.8 +/- 2.3 x 10(3) erg/g (mean +/- standard error of the mean). Under similar conditions, PFC-reperfused hearts achieved a SWI of 14.6 +/- 1.3 x 10(3), significantly greater than that of WB (p less than 0.001). SWI for PFC+ hearts was 19.8 +/- 1.6 x 10(3), significantly increased over that of PFC (p less than 0.01), and not different from values obtained for C (19.2 +/- 0.8 x 10(3)). In addition, PFC-reperfused hearts demonstrated superior maintenance (p less than 0.05) of ATP (2.08 +/- 0.16 umole/g), compared to WB (1.50 +/- 0.19), while preservation of ATP in PFC+ hearts (2.99 +/- 0.12), was significantly increased over that of PFC (p less than 0.001), and not significantly different from that for C (2.68 +/- 0.17).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1992

Modified Fontan procedure in patients less than 4 years of age.

BACKGROUND: Initial experience with the modified Fontan procedure in patients < 4 years of age has met with variable success, with early reports showing a high mortality. More recently, improved results with the modified Fontan procedure in younger patients have been achieved. Important advantages of an early Fontan include protection of the pulmonary vascular bed and preservation of ventricular function by reduction in ventricular volume overload and chronic hypoxemia. METHODS AND RESULTS: From 1982 through May 1991, 90 patients < 4 years of age underwent a modified Fontan procedure. The average age was 29 months (range, 7-48 months), and 30 patients were < 2 years of age. Diagnoses included tricuspid atresia in 36, single ventricle in 45, pulmonary atresia intact septum in seven, and hypoplastic left heart syndrome in two patients. An adjustable ASD was placed in 21. Early mortality was 8.9% (eight of 90), which is only slightly higher than our overall Fontan early mortality of 7.4% in 242 patients. The early mortality in the 30 patients < 2 years of age was 6.7% (two of 30). In a mean follow-up of 38 months (range, 7-89 months), there have been three late deaths (3.7%), and one patient has undergone cardiac transplantation. CONCLUSIONS: Early Fontan should be undertaken in patients > 6 months old who present with increasing cyanosis provided good hemodynamics are present. A modified Fontan procedure can be performed safely with good clinical results in patients < 4 years old.

Anastomosis, Surgical↗
PubMed1992

Partial biventricular repair of pulmonary atresia with intact ventricular septum. Use of an adjustable atrial septal defect.

BACKGROUND: Repair of pulmonary atresia with intact ventricular septum (PA-IVS) is one of the more challenging problems in congenital heart surgery. The hypertrophied but hypoplastic right ventricle is suddenly presented with an increased volume load as the right-to-left shunt is abolished by closure of the atrial septal defect (ASD) as part of definitive repair. We have proposed that a restrictive, adjustable ASD that allows a controlled right-to-left shunt may prevent excessive venous hypertension and allow adequate left-sided filling after biventricular repair of PA-IVS. METHODS AND RESULTS: From 1982 through 1991, 39 patients presented for definitive repair of PA-IVS. Nineteen of these patients were thought to be suitable candidates for biventricular repair, and the other 20 underwent a modified Fontan procedure. An adjustable ASD was used in 12 of the 19 patients undergoing biventricular repair. Mean age was 24 months (age range, 5-66 months). Two patients had their ASD snared closed in the operating room after coming off bypass. In the other 10 patients, closure of the ASD could not be tolerated at the time of surgery as evidenced by elevation of right atrial pressures by > 15 mm Hg and decreased blood pressure when closure was attempted. Seven patients had their open ASDs closed by the snare device, and one patient had his ASD narrowed in the early postoperative period. One patient underwent delayed closure 16 months after surgery. There was one hospital death. CONCLUSIONS: The snare-controlled adjustable ASD allows partial biventricular repair of PA-IVS, reducing the risk of low cardiac output and severe venous hypertension in the postoperative period.

Aortic Valve↗
PubMed1992

Quantification of flow through an interatrial communication. Application to the partial Fontan procedure.

The partial Fontan procedure has become an accepted alternative for the high-risk candidate. Creation of a small right-to-left shunt will lower the systemic venous pressure and improve systemic cardiac output while maintaining an acceptable systemic arterial saturation. However, because of variations in patient size and postoperative transpulmonary gradient, proper sizing of the residual defect is difficult. We have therefore conducted a series of experiments on a model that simulates the blood flow across interatrial defects of varying sizes at several pressure gradients. We used porcine blood to develop guidelines for the sizing of the residual defect. Our results demonstrate a linear relationship between flow and pressure gradient across all hole sizes tested. In addition, there was a linear relationship between atrial septal defect size and flow at each pressure gradient. Our data show that the Gorlin formula predictions overestimated flow by 10% to 40%. It is evident from these data that relatively small changes in the size of the atrial septal defect or in the pressure gradient result in significant changes in flow. Therefore we advocate the use of an adjustable interatrial communication such as the snare-controlled adjustable atrial septal defect for patients undergoing partial Fontan procedures.

Arteriovenous Shunt, Surgical↗
PubMed1992

The inferior epigastric arteries as coronary bypass conduits. Size, preoperative duplex scan assessment of suitability, and early clinical experience.

We are currently evaluating the inferior epigastric artery as an alternative arterial conduit for coronary bypass grafting. Fifty-seven inferior epigastric arteries were harvested from 47 adults. There were no differences in size between the right and left inferior epigastric arteries. Diameter was 2.5 to 3.5 mm proximally and 2 to 3 mm distally. Usable length was 6 to 16 cm (mean 11.2 +/- 0.25 cm). Grade I/IV atherosclerosis was found in one patient (2.1%). Duplex scanning was used for preoperative evaluation of the inferior epigastric arteries in 51 patients. In 21 patients the arteries were not harvested, in part because of duplex scan findings of small caliber or early bifurcation. In 30 patients the duplex findings could be compared with the surgical findings. The average length at operation was twice the length detected on duplex scan (11.2 cm versus 5.8 cm, p less than 0.001). There was a good correlation between diameter on duplex scan and that measured at operation (2.56 +/- 0.05 versus 2.62 +/- 0.07, p = not significant). Between December 1989 and May 1991, 38 patients (29 to 74 years, mean 56 years) received 42 inferior epigastric artery grafts. Proximal anastomoses were to the aorta in 17, to the vein graft hood in 20, or onto an internal mammary artery graft in 5. Distal anastomoses were to the left anterior descending artery in 2, the diagonal branch in 27, the marginal branch in 9, or the right coronary artery in 4. There were no early deaths. Complications included perioperative myocardial infarction in 1, deep sternal wound infection in 2, superficial infection at the harvest site of the inferior epigastric artery in 5, and reexploration for bleeding in 2. Because of its size and the low incidence of atherosclerosis, the inferior epigastric artery may evolve as an alternative arterial conduit for coronary bypass. Duplex scanning is a valuable noninvasive tool for preoperative evaluation of the artery's suitability. Long-term studies of patency of the inferior epigastric artery as a coronary bypass conduit are needed.

Abdominal Muscles↗
PubMed1992

Management of the left atrioventricular valve in the repair of complete atrioventricular septal defects.

Left atrioventricular valve regurgitation in atrioventricular canal defects is usually due to malalignment of the edges of the cleft or to annular dilatation. Intraoperative assessment and correction of left atrioventricular valve incompetence is critical for successful outcome in the surgical management of complete atrioventricular canal defects. Although some have elected not to suture the cleft in the setting of minimal incompetence, we have found that this often results in significant left atrioventricular valve insufficiency, necessitating reoperation. From January 1982 through December 1990, 105 patients with complete atrioventricular canal underwent definitive repair. Repair was performed with a single pericardial patch technique in 86 patients (82%). Intraoperative assessment of left atrioventricular valve competence was performed in all cases. Ninety-six patients (91%) required suturing of the cleft and 63 (60%) required annuloplasty to establish satisfactory competence of the left atrioventricular valve. The overall early mortality rate was 10.5% (11/105 patients). From 1986 to 1990, the early mortality rate decreased to 7.7% (6/78 patients). In a mean follow-up of 39 months (range 1 to 106 months), late survival was 96% (90/94 operative or early survivors). Reoperation was performed on eleven (11.5%) patients; six (6.3%) for failure of the atrioventricular valve repair, three for patch dehiscence, and two for residual ventricular septal defects. These data demonstrate that routine approximation of the cleft and aggressive use of left atrioventricular valve annuloplasty is safe and results in an excellent outcome with a low incidence of reoperation for failure of left atrioventricular valve repair.

Endocardial Cushion Defects↗
PubMed1991

Repair of truncus arteriosus in infancy.

Improvements in myocardial protection, surgical technique, and postoperative care have decreased operative mortality for neonatal repair of truncus arteriosus. Primary repair of truncus arteriosus in infancy without prior pulmonary artery banding is currently the preferred approach. During the period from 1982 to December 1990, 32 patients under the age of 12 months underwent surgical correction of truncus arteriosus at UCLA. The average age was 3.5 months (range, 12 days to 12 months). Three patients had interrupted aortic arch. Early mortality for the entire group was 15.6% (5/32); for those older than 1 month early mortality was 7% (2/28). In the past 4 years, early mortality has decreased to 8.3% (2/24); both of these patients had interrupted aortic arch. Excluding patients with interrupted aortic arch, there were no early deaths in the last 22 patients (1986 to 1990). Late mortality overall was 7.4% (2/27). In a mean follow-up of 73 months (range, 40 to 110 months), 71% (5/7) of the survivors with Dacron porcine-valved conduits required conduit replacement secondary to obstruction. In a mean follow-up of 36 months (range, 1 to 89 months), only 14% (3/21) of the patients with homografts required replacement secondary to obstruction.

Age Factors↗
PubMed1991

Partial Fontan: advantages of an adjustable interatrial communication.

Systemic venous hypertension after the Fontan procedure is a major cause of mortality and morbidity, accounting for 11 of 16 deaths in our series of 228 Fontan procedures. A partial Fontan with a residual atrial septal defect (ASD) would allow controlled right-to-left shunting to reduce venous pressure and improve cardiac output while maintaining a reduced but acceptable arterial oxygen saturation. This allows complete or graded closure of the ASD after the discontinuation of cardiopulmonary bypass in the operating room or at any time in the postoperative period by exposing the snare under local anesthesia. From 1987 to 1990, 36 patients undergoing the modified Fontan procedure had placement of an adjustable interatrial communication. Indications for placement of an adjustable ASD included increased pulmonary artery pressures, increased pulmonary vascular resistance, reactive airway disease, previously increased or unknown pulmonary vascular resistance, small pulmonary arteries, and borderline ventricular function. Fourteen patients had the adjustable ASD closed at the time of operation, 8 patients underwent narrowing, and 12 underwent closure of the ASD in the postoperative period. Eight patients were discharged with the ASD partially open, and 2 patients underwent delayed closure. The partial Fontan with an adjustable ASD may increase the safety of the Fontan procedure for high-risk groups such as those with increased pulmonary vascular resistance, pulmonary hypertension, and impaired left ventricular function and for infants, who tolerate venous hypertension poorly. The ability to adjust the ASD in stages depending on the hemodynamic response increases flexibility and safety.

Animals↗
PubMed1991

Total cavopulmonary anastomosis versus conventional modified Fontan procedure.

The total cavopulmonary anastomosis, lateral tunnel Fontan, has been advocated as a preferred method for Fontan type repair. From 1987 to July 1990, 39 patients underwent total cavopulmonary anastomoses (group 1) and 39 patients underwent modified Fontan procedures (group 2); patients receiving adjustable atrial septal defects were excluded. Diagnoses in group 1 included tricuspid atresia in 5 patients, single ventricle in 32, and pulmonary atresia and intact ventricular septum in 2. Diagnoses in group 2 included tricuspid atresia in 20, single ventricle in 17, hypoplastic left heart syndrome in 1, and pulmonary atresia and intact ventricular septum in 1. There were no significant differences in age, weight, cross-clamp time, duration of inotropic support, postoperative effusions, or hospital stay between the two groups. Early mortality in group 1 was 7.7% (3/39) and in group 2, 2.6% (1/39). There was no difference in the incidence of early dysrhythmias or early pacemaker placement. Late mortality was 2.8% in group 1 and 8% in group 2 with a mean follow-up of 18 and 25 months, respectively. Follow-up in group 1 revealed 33 patients in normal sinus rhythm and 1 patient with episodes of supraventricular tachycardia; no additional patients have required pacemakers. Follow-up in group 2 revealed 27 patients in normal sinus rhythm and supraventricular tachycardia in 4 patients; 5 additional patients have required pacemaker placement. There is no apparent difference in early outcome between the total cavopulmonary anastomosis and the conventional modified Fontan. However, there appears to be an increased incidence of late dysrhythmias and the need for pacemaker placement in the conventional modified Fontan group compared with the lateral tunnel group.

Adolescent↗
PubMed1991

Results of total cavopulmonary connection in the treatment of patients with a functional single ventricle.

Total cavopulmonary connection was proposed as a modification of the Fontan procedure that might have greater benefits than previous methods. To assess this procedure we reviewed case histories of 38 patients (aged 17 months to 30 years) who underwent Fontan procedures with cavopulmonary anastomoses between January 1987 and December 1989. The group included 32 patients with univentricular heart, 2 with pulmonary atresia and intact ventricular septum, 3 with tricuspid atresia, and 1 with hypoplastic left heart syndrome. One or more previous palliative procedures were performed in 34 patients, including 19 systemic-pulmonary shunts, 16 pulmonary artery bandings, 7 atrial septectomies/septostomies, 7 Glenn shunts, and 1 patent ductus arteriosus ligation. Preoperative hemodynamics showed a pulmonary artery pressure of 12 mm Hg (range 6 to 22 mm Hg), pulmonary-systemic flow ratio of 1.6 (range 0.37 to 3.0), left ventricular end-diastolic pressure 9 mm Hg (range 3 to 15 mm Hg), and systemic arterial oxygen saturation of 82% (range 67% to 94%). Concomitant with cavopulmonary connection, 13 patients underwent additional procedures, including 9 atrioventricular valve annuloplasties, 4 Damus-Stansel-Kaye procedures, and 2 resections of subaortic membranes. Modifying the Fontan procedure in this fashion was particularly useful in the management of 2 patients with pulmonary atresia and intact ventricular septum who had right ventricular-dependent coronary blood flow. Cavopulmonary anastomosis and atrial septectomy were performed in both patients, with resultant inflow of oxygenated blood to the right ventricle and coronary arteries. Excellent postoperative results were noted in each. Postextubation hemodynamics for the entire group included a mean right atrial pressure of 13 mm Hg (range 11 to 17 mm Hg), a mean left atrial pressure of 6 mm Hg (range 3 to 12 mm Hg), and a room air oxygen saturation of 96% (range 92% to 98%). Seven patients had pleural effusions, 3 required postoperative pacemaker placement, and 2 required reoperation for tamponade. A venous assist device was required in one patient on the second postoperative day, but the patient was weaned successfully within 24 hours. One early death (2.6%) occurred in a patient who had intractable ventricular fibrillation 2 days after operation. There was one late cardiac death (2.7%) caused by ventricular failure and one late noncardiac death. These results demonstrate that total cavopulmonary connection provides excellent early definitive treatment, with low morbidity and mortality, for a variety of complex congenital heart lesions.

Adolescent↗
PubMed1991

Improved methods in long term venous access using the P.A.S. Port.

An over-all lower cost implantable chronic venous access is readily accomplished using the Cath-finder and implantable P.A.S. Port. This system has few complications and is less expensive, time saving and easy to maintain. The Cath-finder system allows the surgeon to access accurately the central venous circulation without the use of a fluoroscope. The implantable P.A.S. Port has wide acceptance with many types of patients, including those with tumors, cystic fibrosis and AIDS.

Catheterization, Central Venous↗
PubMed1988

Delayed pelvic abscess eight years after generalized peritonitis.

Recently, during a locally severe epidemic of gastroenteritis, a young woman presented, with the symptoms prevalent in her community, harboring an intraabdominal abscess. The case is presented along with a discussion of unusual and delayed presentations of abscesses in the literature. Early diagnosis is imperative because of the very significant morbidity and mortality accompanying delayed treatment.

Abdomen↗