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Reports on the usefulness of corticosteroid therapy in decreasing epinephrine requirements in critically ill infants with congenital heart disease. Baseline characteristics of patients involved in the study; Assessment of heart rate, blood pressure and white blood cell count before and after steroids; Indication of decreases in epinephrine dose.

Background: There is a need for a device that can be used to objectively evaluate the image quality provided by laparoscopic camera units in the operating room., Methods: The device that we developed consists of a regular 10-mm or 5-mm laparoscopic port with a rectangular test unit built at the end. A standard test pattern slide with resolution bars is used for measurements. Using this assembly, a single-chip laparoscopic camera was compared with a three-chip laparoscopic camera at different wiring formats and camera settings by measuring the resolution on the monitor screen., Results: Vertical resolution was found to be constant at 550 lines, regardless of the type of camera and wiring used. Of the three wiring formats, composite wiring provided the poorest image with both cameras. When enhancement was off, the horizontal resolution obtained with Y/C or RGB wiring was the same for the one-chip camera at 640 lines of horizontal resolution, whereas RGB cabling provided the best image for the three-chip camera at 800 lines., Conclusion: Using basic broadcasting principles, we have developed a simple device that is useful for the comparison of different camera, cabling, and laparoscope configurations in the operating room. This information can be used as objective criteria to judge the image quality in laparoscopic video- systems.

Disruption of any one of a large number of balanced systems that maintain cardiomyocyte structure and function can cause myocardial dysfunction. Such disruption can occur either in response to acute stresses such as cardiac surgery with cardiopulmonary bypass and cross-clamping of the aorta or because of more chronic stresses resulting from factors such as genetic abnormalities, infection, or chronic ischemia. Several currently available therapies such as beta-adrenergic receptor agonists and antagonists, phosphodiesterase inhibitors, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and other agents affect cardiomyocytes in ways that are more far reaching than initially appreciated when these agents were first introduced into clinical practice. As our knowledge and understanding of myocardial dysfunction increases, particularly in the neonatal and pediatric patient, we will be able to further target interventions to highly specific perturbations of cellular function and individual genetic variability.

Background: The use of the Veress needle in laparoscopy to create the pneumoperitoneum has inherent risks; it may cause vascular and visceral injuries. The open technique is compromised by the leakage of carbon dioxide and can also be time consuming. One alternative is to enter the abdomen using an optical trocar under direct view. Our aim was to determine whether the optical access trocar can be used to effect a safe and rapid entry in various laparoscopic procedures., Methods: Over a 4-year period, the Optiview trocar was used for initial entry in 650 laparoscopic procedures. The procedures included cholecystectomy (n = 282), transabdominal inguinal hernia repair (n = 76), radiofrequency ablation of liver tumors (n = 73), adrenalectomy (n = 54), appendectomy (n = 41), colorectal surgery (n = 39), and various other procedures (n = 85). The following parameters were analyzed: presence of previous abdominal operations, site and duration of entry, and complications., Results: Of the 650 patients, 156 (24%) had had previous abdominal operations. In 25 cases, previous trocar sites were reused for optical access. The optical trocar was inserted at the umbilicus in 495 patients (76%), in the right upper quadrant in 77 (12%), in the left upper quadrant in 26 (4%), in the upper midline in eight (1%), in the right lower quadrant in six (0.9%), and in the left lower quadrant in three (0.5%). In 35 patients undergoing posterior adrenalectomy, optical trocars were used to enter Gerota's space. Mean (SD) entry times were 92 (45) sec at the umbilical site, 114 (30) sec at the back, and 77 (35) sec at the remaining sites. Complications (0.3%) included one injury to the bowel and one injury to the gallbladder; however, they were recognized and repaired immediately., Conclusions: To our knowledge, this report comprises the largest series in which the optical access trocar was used for laparoscopic surgery. This device provides the basis for a safe and fast technique for initial trocar placement: it also has the potential to reduce costs. Thanks to our favorable experience, the optical trocar method has become the standard technique for abdominal access in our laparoscopic practice since 1995.

Background: Accurate staging of malignant tumors in the liver has major implications in defining prognosis and guiding both surgical and nonsurgical therapy. Intraoperative ultrasound in open surgery compares favorably with computed tomography (CT) in the detection of liver tumors; however, there is little experience with laparoscopic ultrasound (LUS)., Hypothesis: Laparoscopic ultrasound is more sensitive than triphasic CT for detecting primary and metastatic liver tumors., Design: Prospective study., Setting: University hospital., Patients: Fifty-five patients with a total of 222 lesions, including primary and metastatic liver tumors, who underwent both CT examinations and LUS as a part of a tumor ablation procedure., Interventions: Triphasic spiral CT scans of the liver were obtained within 1 week before surgery. Liver LUS was performed with a linear 7.5-MHz side-viewing laparoscopic transducer., Results: The LUS detected all 201 tumors seen on preoperative CT and detected 21 additional tumors (9.5%) in 11 patients (20.0%). These tumors missed by CT ranged in size from 0.3 to 2.7 cm. Smaller tumors tended to be missed by CT scan (28.6% of the lesions <1 cm, 15.8% of those 1-2 cm, 4% of those 2-3 cm, and 0% of those >3 cm), as did those in segments III and IV. There was good correlation between the size of lesions imaged by the 2 modalities (Pearson r = 0.86; P<.001)., Conclusion: Laparoscopic ultrasound offers increased sensitivity over CT for the detection of liver tumors, especially for smaller lesions. This study documents the ability of LUS in detecting liver tumors and argues for more widespread use in laparoscopic staging procedures.

Objective: Changes in exhaled nitric oxide levels often accompany conditions associated with elevated pulmonary vascular resistance and altered lung mechanics. However, it is unclear whether changes in exhaled nitric oxide reflect altered vascular or bronchial nitric oxide production. This study determined the effects of acute hypoxia and reoxygenation on pulmonary mechanics, plasma nitrite levels, and exhaled nitric oxide production., Methods: Ten piglets underwent 90 minutes of hypoxia (fraction of inspired oxygen = 12%), 1 hour of reoxygenation on cardiopulmonary bypass, and 2 hours of recovery. Five additional animals underwent bypass without hypoxia. Exhaled nitric oxide, plasma nitrite levels, and pulmonary mechanics were measured., Results: Exhaled nitric oxide decreased to 36% of baseline by end hypoxia (34 +/- 14 vs 12 +/- 9 ppb, P =.005) and declined further to 20% of baseline at end recovery (7 +/- 6 ppb). Aortic nitrite levels decreased from baseline during hypoxia (from 102 +/- 13 to 49 +/- 7 micromol/L, P =.05) but returned to baseline during recovery. Pulmonary arterial nitrite also decreased during hypoxia (from 31.4 +/- 7.8 to 22.9 +/- 9.5 micromol/L, P =.04) and returned to baseline at end recovery. Decreased production of exhaled nitric oxide was associated with impaired gas exchange (alveolar-arterial gradient = 32 mm Hg at baseline and 84 mm Hg at end recovery), decreased pulmonary compliance (6.6 +/- 0.9 mL/cm H(2)O at baseline, 5.0 +/- 0.7 mL/cm H(2)O at end hypoxia, and 5.4 +/- 0.7 mL/cm H(2)O at end recovery), and increased inspiratory airway resistance (41 +/- 4 cm H(2)O. L(-1). s(-1) at baseline, 56 +/- 4.9 cm H(2)O. L(-1). s(-1) at end hypoxia, and 50 +/- 5 cm H(2)O. L(-1). s(-1) at end recovery)., Conclusions: A decrease in exhaled nitric oxide persisted after hypoxia, and plasma nitrite levels returned to baseline on reoxygenation, indicating that alterations in exhaled nitric oxide during hypoxia-reoxygenation might be unrelated to plasma nitrite levels. Furthermore, decreased exhaled nitric oxide corresponded with altered pulmonary mechanics and gas exchange. Reduced exhaled nitric oxide after hypoxia-reoxygenation might reflect bronchial epithelial dysfunction associated with acute lung injury.

Purpose: Tunneled catheters are an alternative means of vascular access for patients in need of hemodialysis who cannot undergo dialysis through a surgical shunt. This study was undertaken to evaluate the performance of the Tesio dialysis catheter., Materials and Methods: A prospective study of the Tesio catheter was performed. Follow-up data regarding catheter function and adequacy of dialysis were obtained from nine hemodialysis facilities., Results: Seventy-nine Tesio catheters were placed in 71 patients. Immediate technical success was 99% (78 of 79 catheters). The procedure complication rate was 9% (seven catheters). Only two complications required intervention: one fatal air embolism and one chest wall hematoma. Sixty-seven catheters in 60 patients were followed up for a total of 4,367 catheter days. Overall, catheter-related infection occurred in 9% (six of 67 catheters). Primary catheter patency was 87% at 1 week, 82% at 1 month, 72% at 3 months, and 66% at 6 months. Mean blood flow was 286 mL/min immediately after insertion, 301 mL/min at 3 months, and 306 mL/min at 6 months. Adequate dialysis dose as reflected by a urea reduction ratio of 60 or more or a urea kinetic modeling, or Kt/V, value of 1.2 or more was observed on at least one occasion for 74% and 76% of catheters, respectively., Conclusion: The Tesio catheter is a reasonable means of vascular access for patients who undergo dialysis but are not candidates for surgical shunt placement.

Hypothesis: Tube cholecystostomy followed by interval laparoscopic cholecystectomy is a sale and efficacious treatment option in critically ill patients with acute cholecystitis., Design: Retrospective cohort study within a 4 1/2%-year period., Setting: University hospital., Patients: Of 324 patients who underwent laparoscopic cholecystectomy, 65 (20%) had acute cholecystitis; 15 of these 65 patients (mean age, 75 years) underwent tube cholecystostomy., Intervention: Thirteen patients at high risk for general anesthesia because of underlying medical conditions underwent percutaneous tube cholecystostomy with local anesthesia. Laparoscopic tube cholecystostomy was performed on 2 patients during attempted laparoscopic cholecystectomy because of severe inflammation. Interval laparoscopic cholecystectomy was attempted after an average of 12 weeks., Main Outcome Measures: Technical details and clinical outcome., Results: Prompt clinical response was observed in 13 (87%) of the patients after tube cholecystostomy. Twelve patients (80%) underwent interval cholecystectomy. Laparoscopic cholecystectomy was attempted in 11 patients and was successful in 10 (91%), with 1 conversion to open cholecystectomy. One patient had interval open cholecystectomy during definitive operation for esophageal cancer and another had emergency open cholecystectomy due to tube dislodgment. Two patients (13%) had complications related to tube cholecystostomy and 2 patients died from sepsis before interval operation. One patient died from sepsis after combined esophagectomy and cholecystectomy. Postoperative minor complications developed in 2 patients. At a mean follow-up of 16.7 months (range, 0.5-53 months), all patients were free of biliary symptoms., Conclusions: Tube cholecystostomy allowed for resolution of sepsis and delay of definitive surgery in selected patients. Interval laparoscopic cholecystectomy was safely performed once sepsis and acute infection had resolved in this patient group at high risk for general anesthesia and conversion to open cholecystectomy. Just as catheter drainage of acute infection with interval appendectomy is accepted in patients with periappendiceal abscess, tube cholecystostomy with interval laparoscopic cholecystectomy should have a role in the management of selected patients with acute cholecystitis.

Background: Acute hypoxia results in increased pulmonary vascular resistance. Despite reoxygenation, pulmonary vascular resistance remains elevated and pulmonary function is altered. Endothelin-1 might contribute to hypoxia-reoxygenation-induced pulmonary hypertension and to reoxygenation injury by stimulating leukocytes. This study was carried out using an established model of hypoxia and reoxygenation to determine whether endothelin-1 blockade with Bosentan could prevent hypoxia-reoxygenation-induced pulmonary hypertension and reoxygenation injury., Methods: Twenty neonatal piglets underwent 90 minutes of hypoxia, 60 minutes of reoxygenation on cardiopulmonary bypass, and 2 hours of recovery. Control animals (n = 12) received no drug treatment, whereas the treatment group (n = 8) received the endothelin-1 receptor antagonist, Bosentan, throughout hypoxia., Results: In controls, pulmonary vascular resistance increased during hypoxia to 491% of baseline and remained elevated after reoxygenation; however in the Bosentan group, it increased to only 160% of baseline by end-hypoxia, then decreased to 76% at end-recovery. Arterial endothelin-1 levels in controls increased to 591% of baseline after reoxygenation. Arterial nitrite levels decreased during hypoxia in controls but were maintained in the Bosentan group. Consequently, animals in the Bosentan group had better postreoxygenation pulmonary vascular resistance, A-a gradient, and airway resistance along with lower myeloperoxidase levels than controls., Conclusions: Acute hypoxia and postreoxygenation pulmonary hypertension was attenuated by Bosentan, which maintained nitric oxide levels during hypoxia, decreased leukocyte-mediated injury, and improved pulmonary function.

The surgical management of patients with complete atrioventricular canal has evolved over the past 20 years from a staged approach with preliminary pulmonary artery banding and eventual definitive repair, to an era of complete repair in early infancy. Although once considered high risk, the early mortality is now low and is primarily related to pulmonary hypertension secondary to a prolonged delay in diagnosis and referral. While controversy still exists over the techniques of repair, evaluation of outcome of atrioventricular canal should now be focused on the long-term function of the mitral valve, and the overall long-term survival. A detailed description of the single-patch technique and management of the atrioventricular valve, as well as an indepth discussion of outcome is presented.

Unlabelled: The purpose of this report is to review our surgical experience with primum atrial septal defect. Since 1982, infants with primum atrial septal defect have undergone complete repair consisting of closure of the cleft of the left atrioventricular valve and atrial septal defect with a pericardial patch. Ages at operation ranged from early neonatal period until 5 years. In most patients, echocardiography was diagnostic and cardiac catheterization was performed in children with associated defects. Severe congestive heart failure and left atrioventricular valve regurgitation necessitated earlier correction. Infants with coarctation of the aorta and primum atrial septal defect underwent a two-stage procedure involving coarctation resection followed by complete repair. The early mortality rate is less than 1% and has a reoperation rate of less than 3%. The overall long-term survival of patients with primum atrial septal defect matches that of the general population., Conclusion: The diagnosis of primum atrial septal defect can easily be made by echocardiography with cardiac catheterization reserved for patients with associated left-sided obstruction. For patients in stable condition, the total repair can be performed before 2 to 3 years of age with minimum mortality. In infants with severe congestive heart failure, earlier correction should be contemplated, although it carries a higher morbidity. The associated coarctation of aorta is infrequent, but requires resection before intracardiac repair. The long-term results with this lesion repair are excellent.

Amino acid enrichment of cardioplegic solutions has been shown to improve both the metabolic and functional recovery of ischemic myocardium. However, because of the marked systemic vasodilatation involved, use of amino acid enrichment is limited to the periods of induction and reperfusion. Fumarate is a Krebs' cycle intermediate whose conversion to succinate is responsible for the generation of adenosone triphosphate and the oxidation of the reduced form of nicotinamide-adenine nucleotide which is the pathway by which aspartate exerts its effect. Fumarate may also function as a free-radical scavenger and is involved in calcium transport. To determine if fumarate-enriched blood cardioplegia would improve the functional recovery of the neonatal heart, 14 neonatal piglet hearts were isolated and placed on a blood-perfused working heart circuit. After the baseline functional and metabolic assessment was done, cold ischemic arrest was initiated with either standard blood cardioplegic solution (group I; N = 7) or fumarate-enriched (13 mmol/L) blood cardioplegic solution (group II; N = 7). Cardioplegic solution was given at a pressure of 40 mm Hg every 20 minutes for 2 hours, and topical hypothermia was used. Sixty minutes after warm whole blood reperfusion, the functional recovery at left atrial pressures of 3, 6, 9, and 12 mm Hg was 70%, 66%, 66%, and 65%, respectively, in group I, versus 102%, 106%, 105%, and 109%, respectively, in group II (p < 0.05). The tissue creatinine phosphate levels after reperfusion were significantly higher in group II hearts (15.0 +/- 1.2 mumol/g dry heart tissue) than in group I hearts (9.2 +/- 1.9 mumol/g dry heart tissue), although the adenosine triphosphate levels were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

The concept of the partial Fontan procedure, first described with the adjustable atrial septal defect (ASD) and more recently with the fenestrated technique, has become an accepted approach for the management of high-risk patients undergoing the Fontan procedure. Experience with both techniques has shown that a patent ASD placed in a prosthetic interatrial baffle may close spontaneously over a period of weeks to months. The mechanism and timing of spontaneous closure, as well as the effect of antiplatelet therapy on this process, are poorly understood. To better define this process, the interatrial septum of 15 mongrel dogs was excised and replaced with a fenestrated Gore-Tex (W.L. Gore, Flagstaff, AZ) patch. Postoperative echocardiography confirmed the patency of the ASD and left-to-right shunting. Animals were sacrificed 4 to 6 weeks postoperatively, or sooner if infection or other postoperative complications developed. Eight animals underwent no antiplatelet or anticoagulation therapy postoperatively, and 7 received antiplatelet therapy with aspirin. Patches were removed at the end of the study period and analyzed. By 6 weeks, all 2.7-mm and 4-mm holes had closed spontaneously in all animals that had not received antiplatelet therapy. The earliest closure occurred at 1 week. With antiplatelet therapy, hole closure was found to be delayed but not prevented, and was complete by 6 weeks in all but 1 animal. Histologic examination of the explanted patches revealed that closure was accomplished primarily through the ingrowth of fibrous tissue, accompanied by an inflammatory cell infiltrate.(ABSTRACT TRUNCATED AT 250 WORDS)

The truncal valve regurgitation that frequently arises in patients with truncus arteriosus accounts for increased operative and late mortality. Five patients underwent truncal valve repair at UCLA Medical Center between August 1990 and September 1991. This group consisted of 2 infants who underwent complete repair and 3 who underwent valve repair together with right ventricle-pulmonary artery conduit replacement. The techniques used for repair were individualized according to the specific valve morphology, and consisted of the suturing of partially developed commissures, suspension of the cusps, resection of redundant portions of the cusps, annuloplasty at the commissures, and resection of excrescences on the surface of valve leaflets. In 1 infant who had a severely dysplastic truncal valve, stenosis and regurgitation recurred and progressed, and he died 4 months after truncal valve replacement. The remaining 4 patients, who were followed for from 8 to 21 months after repair, are in New York Heart Association class I, and have minimal or no aortic regurgitation. Except in patients with severely deformed and dysplastic valves, truncal valve repair can be an attractive and successful alternative to valve replacement.

University of Wisconsin solution has proved to be a superior form of cardioplegia for cardiac transplantation, demonstrating better functional recovery than that provided by extracellular crystalloid solutions. Furthermore, experimental data have suggested a role for University of Wisconsin solution in protection of the neonatal heart during operations for congenital heart defects. However, significant concerns have been raised regarding potential endothelial injury from the high potassium concentration contained in University of Wisconsin solution that could affect its safety and thus its clinical application. Fourteen neonatal (aged 1 to 3 days) piglet hearts were harvested and supported on an isolated, blood-perfused circuit. Endothelium-dependent vasodilatation was measured by bradykinin (10(-6) mol/L) infusion and nitric oxide release was determined. Endothelium-independent vasodilatation was then induced by sodium nitroprusside (10(-6) mol/L) infusion. A 2-hour period of cold cardioplegic arrest was instituted with multidose University of Wisconsin solution (group 1, n = 7) or blood cardioplegia (group 2, n = 7). After reperfusion and stabilization, another stimulation with bradykinin and nitroprusside was carried out and nitric oxide was again measured. After 2 hours of arrest with University of Wisconsin solution, there was a near-complete loss of vasodilatation in response to bradykinin infusion; coronary blood flow reached 245% of baseline before arrest versus only 117% of baseline after arrest (p = 0.0011). This correlated with an inability of the endothelium to release nitric oxide (96 +/- 30 nmol/min before arrest versus -32 +/- 9 nmol/min after arrest, p = 0.0039. In group 2, the vasodilatory response to bradykinin was preserved after arrest and reperfusion; 265% of baseline before arrest versus 222% of baseline after arrest. These results demonstrate a loss of endothelium-dependent vasodilatation after multidose University of Wisconsin cardioplegia caused by the inability of the endothelium to release nitric oxide. In contrast, blood cardioplegia does not result in impaired endothelial function.

The precise hemodynamic effects of latissimus dorsi cardiomyoplasty have not been well characterized. We prospectively studied 11 mongrel dogs using a rapid ventricular pacing model of congestive heart failure. Six dogs received a nonstimulated left latissimus dorsi cardiomyoplasty wrap, and 5 control dogs were paced only. Two-dimensional transthoracic echocardiography was performed on all dogs at baseline and then weekly for 4 weeks. Measurements obtained included left ventricular diameters, lengths, volumes, and ejection fractions. Progressive left ventricular enlargement, increase in volumes, and worsening ejection fractions developed in both groups. However, less left ventricular dilatation and higher ejection fractions were seen in dogs that received a cardiomyoplasty wrap. A nonstimulated cardiomyoplasty wrap significantly attenuated the degree of left ventricular enlargement, increase in left ventricular volumes, and decrease in ejection fraction in a rapid pacing model of congestive heart failure. Apart from its effect on systolic augmentation with a stimulated muscle wrap, cardiomyoplasty may have an important "girdling" effect on the left ventricle that prevents dilatation and deterioration of left ventricular function.

In this report, explanted hearts from transplant recipients with the diagnosis of idiopathic cardiomyopathy underwent a blood cardioplegia arrest and extended subatrial resection to preserve their coronary sinus venous system. The coronary sinus and left and right coronary arteries were then cannulated and warm blood cardioplegia retrograde infused at a pressure of 30 to 40 mm Hg. Effluent from the coronary arteries and thebesian veins was then collected. Hearts were subsequently fixed with retrograde glutaraldehyde perfusion and perfused retrograde with NTB-2 (an inert intracapillary marker). Histologic sections were examined from 12 separate sites. There was no significant difference in the percentage of capillaries perfused by retrograde-delivered cardioplegia between corresponding regions of the left and right ventricles. However, effluent analysis indicated that 67.2% +/- 6.4% of retrograde-delivered blood cardioplegia was shunted through thebesian veins, thereby bypassing the microvasculature, whereas 29.3% +/- 6.3% and 3.5% +/- 3.1% traversed the myocardium supplied by the left and right coronary arteries, respectively. The results indicate that all regions of both ventricles are perfused by retrograde blood cardioplegia. However, they also suggest that nutrient flow to the microvasculature of the right ventricle is minimal during retrograde cardioplegia.

Between October 1983 and August 1991, 29 consecutive Damus-Stansel-Kaye procedures were performed. Indications for operation included restrictive bulboventricular foramen or subaortic stenosis associated with complex univentricular congenital heart disease (25) and Taussig-Bing heart, subaortic stenosis, or both associated with complex biventricular congenital heart disease (4). Twelve patients underwent concurrent Fontan procedures. Average age at operation was 39.8 months (range, 1 to 132 months). Average outflow tract gradient was 28 mm Hg (range, dynamic to 80 mm Hg). Of the 29 patients, 23 were male and 6 were female. There were three early deaths (10%), two in patients who had a concurrent Fontan procedure. Although there was a trend toward lower age and higher outflow tract gradients in nonsurvivors, these and other factors were not statistically significant predictors of death. Actuarial freedom from cardiac-related death was 88% at 5 years (n = 7). In a mean follow-up of 3.5 years (range, 0.1 to 7.7 years), 3 patients have required reoperation (10%), 2 for aortic valve insufficiency (5 days and 2.75 years) and 1 for a gradient across the anastomosis (5.75 years). Actuarial freedom from reoperation related to a failed Damus-Stansel-Kaye procedure was 90% at 4 years and 75% at 6 years (n = 7).

Reperfusion injury remains a limiting factor in extending ischemic storage time for human heart transplantation. In this study, initial myocardial reperfusion with an oxygenated perfluorochemical (Fluosol) was investigated as a means of limiting such injury. Neonatal piglet hearts were arrested with crystalloid cardioplegia, excised, and stored for 12 hours in saline solution at 0 degrees C. Initial reperfusion (10 minutes) was either with whole blood (n = 6), unmodified perfluorochemical (n = 8), or aspartate/glutamate-enriched perfluorochemical cardioplegia (n = 6), and was followed by an additional 40 minutes of whole blood perfusion. Functional evaluation was then completed, and left ventricular biopsy specimens were taken. A control group (n = 7) was evaluated without an intervening period of ischemia. At a left ventricular end-diastolic pressure of 9 mm Hg, hearts stored in whole blood cardioplegia developed a left-ventricular stroke work index of 3.8 +/- 2.3 x 10(3) erg/g (mean +/- standard error of the mean). Under the same conditions, perfluorochemical-reperfused hearts achieved a stroke work index of 14.6 +/- 1.3 x 10(3) erg/g, significantly greater than that of the whole blood group (p < 0.001). Stroke work index for hearts reperfused with aspartate/glutamate-enriched perfluorochemical cardioplegia was 19.8 +/- 1.6 x 10(3) erg/g, significantly increased over that of the nonenriched perfluorochemical group (p < 0.01) and not different from values obtained in controls (19.2 +/- 0.8 x 10(3) erg/g).(ABSTRACT TRUNCATED AT 250 WORDS)

Although standard blood cardioplegia provides good myocardial protection for cardiac operations in adults, protection of the cyanotic, immature myocardium remains suboptimal. Calcium, which has been implicated in reperfusion injury and in the development of "stone heart" in mature myocardium, is routinely lowered in standard cardioplegic solutions. Immature, neonatal myocardium has lower intracellular calcium stores and is more reliant on extracellular calcium for contraction. To determine if normocalcemic cardioplegia would result in improved cardiac function in the neonatal heart, we conducted a series of experiments using an isolated, blood-perfused working heart model. Thirty-two neonatal piglet hearts (24 to 48 hours) were excised without intervening ischemia and were placed directly on a blood-perfused circuit. Baseline stroke work index was assessed. Hearts were then arrested with cold cardioplegic solution delivered at 45 mm Hg for 2 minutes: group I, low-calcium blood cardioplegic solution (Ca = 0.6 mmol/L); group II, normal-calcium blood cardioplegic solution (Ca = 1.1 mmol/L); group III, University of Wisconsin solution; and group IV, University of Wisconsin solution with added calcium (Ca = 1.0 mmol/L). Cardioplegic solution was administered every 20 minutes for 2 hours and topical hypothermia was used. Hearts were then reperfused with warm whole blood. Functional recovery, expressed as a percentage of control stroke work index, was determined minutes after reperfusion. Hearts preserved with normocalcemic cardioplegic solution (groups II and IV) had complete functional recovery at 60 minutes, whereas hearts preserved with low-calcium cardioplegic solution (groups I and III) achieved functional recoveries of only 80% and 65%, respectively, at a left atrial pressure of 9 mm Hg. Electron micrographs taken 1 hour after reperfusion showed minimal edema and only mild myofibrillar changes. They were identical in both the low-calcium and normocalcemic groups. Complete functional recovery is possible in immature myocardium when calcium is added to either blood or an intracellular crystalloid cardioplegic solution. The addition of calcium does not result in ultrastructural damage and does result in good functional recovery.

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.

Blood cardioplegia is considered by many to be the preferred solution for myocardial protection. Proposed benefits include the ability to deliver oxygen and the ability to maintain metabolic substrate stores. However, the decreased capacity of blood to release oxygen at hypothermic conditions as well as the presence of deleterious leukocytes, platelets, and complement may limit complete functional recovery. Fluosol is an asanguineous solution with the ability to bind and release oxygen linearly at low temperatures. Neonatal piglet hearts (24 to 48 hours old) were excised and supported on an isolated, blood-perfused working heart model. After baseline stroke-work index was determined, hearts were arrested with either normocalcemic blood cardioplegia (group 1, n = 8) or normocalcemic Fluosol cardioplegia (group 2, n = 8). Cold cardioplegia was administered at 45 mm Hg every 20 minutes for 2 hours. Hearts were then reperfused with whole blood. Functional recovery, expressed as percent of control stroke-work index, was determined 60 minutes after reperfusion at left atrial pressures of 3, 6, 9, and 12 mm Hg. Functional recovery at 60 minutes was similar between group 1 (95%, 93%, 93%, 88%) and group 2 (100%, 94%, 94%, 95%) at left atrial pressures of 3, 6, 9, and 12 mm Hg, respectively. Mean lactate consumption 5 minutes after reperfusion was significantly greater (p = 0.0001) in group 1 (31.8 +/- 6.3 micrograms.min-1 x g-1) than in group 2 (-0.59 +/- 0.1 microgram.min-1 x g-1), indicating superior metabolic recovery in the blood cardioplegia hearts. Edema formation, as determined both by water content (group 1, 81.10%; group 2, 81.63%) and by electron microscopy, was not significantly different between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

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.

Standard methods of myocardial preservation for heart transplantation have generally provided good results. Preservation times beyond 3 hours, however, have been associated with decreased survival. Leukocyte-mediated reperfusion injury is partly responsible for decreased graft function after prolonged graft ischemia. Leukocyte-depleted reperfusion has been shown experimentally to improve cardiac function after cold ischemic arrest. To determine the efficacy and safety of leukocyte-depleted reperfusion, 20 patients were enrolled in a randomized, double-blind clinical trial to be treated with either warm whole blood reperfusion (group I; n = 9) or warm leukocyte-depleted blood reperfusion (group II; n = 11). Reperfusion with leukocyte-depleted blood or whole blood was carried out for 10 minutes, with enriched cardioplegic solution added for the first 3 minutes of reperfusion. The mean donor and recipient age and the ischemic time (142 versus 153 minutes) were not significantly different between the two groups. Coronary sinus release of creatinine phosphokinase-MB 5 minutes after reperfusion was significantly less in group II (1.65 EU/min) than in group I (3.83 units/min; p = 0.05). Thromboxane B2 release was also significantly less (p = 0.05) in group II (33.6 pg/min) than in group I (67.0 pg/min). All hearts functioned adequately in both groups. The duration of inotropic support was shorter in group II than in group I, but the difference was not statistically significant. Postoperative hemodynamics, rejection episodes, and infectious complications were also not significantly different between groups in a mean follow-up of 9 months. Mean ejection fraction 1 month after operation was 65% in both groups. One early death occurred at 66 days secondary to infection; two late deaths occurred in group II, both from rejection. Leukocyte-depleted reperfusion is safe and easily applied in the operating room. Furthermore, leukocyte-depleted reperfusion decreases biochemical evidence of reperfusion injury. Although not influencing postoperative cardiac function when the ischemic time is short, less than 3 hours, leukocyte-depleted reperfusion may prevent significant reperfusion injury and improve posttransplantation graft function when ischemic times are long. Safe extension of the ischemic time would expand the donor pool and allow for better crossmatching.

The Damus-Stansel-Kaye procedure has been applied for the relief of outflow tract obstruction caused by a restrictive bulboventricular foramen or subaortic stenosis in patients with complex univentricular heart disease. The procedure may also be part of a biventricular repair of a Taussig-Bing transposition of the great arteries. This report details technical modifications of the procedure to ensure unobstructed blood flow from the pulmonary artery to the aorta and to maintain the integrity of the pulmonary and aortic valves.

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)

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.

The present study examines whether leukocyte depletion can prevent postreperfusion ultrastructural injury in transplanted human hearts. Thirty-two patients undergoing orthotopic cardiac transplantation were randomized to receive either enriched, warm, whole blood (Group I; n = 16) or enriched, warm, leukocyte-depleted blood (Group II; n = 16) reperfusion. Donor hearts were arrested with 1 liter of 4 degrees C crystalloid cardioplegia and topically cooled. RV endomyocardial biopsies taken at end-ischemia and following reperfusion were assessed in a blinded fashion and graded according to injury (1 = minimal to 4 = severe). The mean ischemic time (Group I = 142 min, Group II = 153 min) was similar in the two groups. End-ischemic biopsies showed mild-moderate interstitial edema and mild capillary endothelial swelling in both groups with similar injury scores (Group 1 = 1.3 +/- 0.09 (means +/- SEM), Group 2 = 1.25 +/- 0.08). Postreperfusion biopsies in Group I showed nuclear chromatin clumping, moderate mitochondrial swelling, marked capillary endothelial swelling, and marked interstitial edema with a grade of 2.6 +/- 0.14 (P less than 0.001, paired t test). In contrast, postreperfusion biopsies in Group II showed minimal changes with a grade of 1.33 +/- 0.09, P less than 0.0001 in comparison to Group I Leukocyte-depleted reperfusion of human transplanted hearts prevents ultrastructural injury. This may allow safe extension of the ischemic period and result in improved graft function.

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.

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)

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.