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Biomedical subjects

M L Jacobs

Publications and source records attributed to M L Jacobs.

At least 37 records · Page 2Linked to original sources
PubMed1998

One-lung Fontan operation: hemodynamics and surgical outcome.

BACKGROUND: This study examined the results of a Fontan operation for patients with acquired atresia of one main branch pulmonary artery. METHODS: The data for 7 patients identified as having a hypoplastic left pulmonary artery discontinuous from the right pulmonary artery were compared with those for 65 patients with continuous pulmonary arteries who consecutively underwent a completion Fontan procedure. RESULTS: No significant differences were found preoperatively with respect to right atrial pressure, aortic saturation, ventricular end-diastolic pressure, pulmonary artery pressure, pulmonary blood flow, or pulmonary vascular resistance. In the first 24 postoperative hours, there were no significant differences in heart rate, urine output, systemic venous pressure, or pulmonary venous pressure. Also, data regarding hospitalization length, effusions, and mortality were similar between the two groups. Postoperative systemic arterial saturation was lower in the one-lung group. There were no early postoperative deaths in the one-lung group, and 5 of the 7 patients are long-term survivors. CONCLUSIONS: A completion Fontan procedure can be successfully performed in patients with a hypoplastic and discontinuous left pulmonary artery, although postoperative systemic arterial saturation is not as high as in patients with continuous pulmonary arteries.

Atrial Function↗
PubMed1998

Intermediate survival in neonates with aortic atresia: a multi-institutional study. The Congenital Heart Surgeons Society.

OBJECTIVE: Controversy persists with regard to the treatment of patients with aortic atresia. Staged reconstructive operations and primary transplantation have been advocated as treatment strategies, but in many instances no treatment is undertaken. A multi-institutional study was undertaken for the purpose of characterizing this challenging patient group, comparing the prevalence and outcomes of the various treatment strategies, and identifying potential predictors of success or failure with each. METHODS AND RESULTS: A total of 323 neonates with aortic atresia were entered into a 21-institution prospective, nonrandomized study between January 1, 1994, and January 1, 1997. Three protocols were used, nonexclusively in many institutions: (1) staged reconstructive surgery with initial palliation by a Norwood procedure and eventual Fontan operation, (2) heart transplantation as initial definitive therapy, and (3) nonsurgical management. Analysis was based on initial protocol assignment: staged reconstructive surgery in 253 patients, heart transplantation in 49 patients, and nonsurgical management in 21 patients. For all patients initially entered into the 2 surgical treatment protocols, survival at 1, 3, 12, 24, and 36 months after entry was 67%, 59%, 52%, 51%, and 50%, respectively. A multivariable analysis found incremental risk factors for death at any time after entry to be lower birth weight (P=.04), associated noncardiac anomaly (P=.007), and entry into the nonsurgical protocol (P < .0001) or the staged reconstructive surgery protocol (P=.03). Four institutions had higher survival statistics; 2 used a heart transplantation protocol and 2 used a staged reconstructive surgery protocol. For the 113 patients treated at these 4 institutions, survival at 1, 3, 12, 24, and 36 months after entry was 77%, 70%, 64%, 62%, and 61%, respectively. Survival among the 4 institutions was similar (P=0.1). CONCLUSIONS: Among patients with aortic atresia, other features of cardiac structure including aortic size, degree of left ventricular hypoplasia, and degree of mitral hypoplasia or atresia are not predictive of survival from 2 surgical protocols. The highest survival was achieved with either treatment strategy at institutions strongly committed to the use of one or the other surgical management protocol.

Aortic Valve↗
PubMed1997

Comparison of patterns of pulmonary venous blood flow in the functional single ventricle heart after operative aortopulmonary shunt versus superior cavopulmonary shunt.

In this study we investigated the patterns of pulmonary venous flow in children with functional single ventricles to obtain a better understanding of the determinants of transpulmonary blood flow. Sixty-eight patients with functional single ventricles and aortopulmonary shunt (n = 34, group I), or superior cavopulmonary connection (n = 34, group II) underwent transesophageal Doppler echocardiographic assessment of flow in the left upper pulmonary vein before undergoing the next stage of surgery. Twelve patients from group II also underwent simultaneous evaluation of superior vena caval flow. Biphasic forward pulmonary venous flow was noted in 62 patients in sinus rhythm (S wave in systole, D wave in diastole); in 6 patients with junctional rhythm, significant early systolic reversal of flow was present. Both the S- and D-wave velocity-time integrals (VTI) were greater in group I than in group II (S(VTI) 9.9 +/- 4.2 vs 8.0 +/- 2.6, p = 0.02; D(VTI) 8.0 +/- 3.5 vs 4.2 +/- 2.6, p <0.001). In both groups, pulmonary venous flow was predominantly systolic; however, the proportion of flow during ventricular systole was significantly greater in group II than in group I (S(VTI)/D(VTI) group II: 2.4 +/- 1.5; group I 1.4 +/- 0.5, p = 0.001; percent systolic fraction of pulmonary venous flow group II = 67%, group I = 56%, p <0.001). Analysis of superior vena caval flow in group II revealed a single predominant wave with onset at early systole and peak in late systole at a mean of 150 ms after the pulmonary venous S-wave peak. Our data suggest that ventricular systole (i.e., atrial relaxation, atrioventricular valve descent) asserts great influence on transpulmonary blood flow in the functional single ventricle.

Echocardiography, Doppler↗
PubMed1997

Late surgical fenestration for complications after the Fontan operation.

BACKGROUND: Significant morbidity after Fontan operation results in either takedown, heart transplantation, or death. Initial creation of a fenestration results in less morbidity and mortality; however, the role of late creation of a fenestration in aiding patients manifesting morbidity after an initial nonfenestrated Fontan operation is unclear. METHODS AND RESULTS: We reviewed our experience with late creation of a surgical fenestration in 9 patients (5.2 +/- 3.1 years old) exhibiting chronic effusions (n = 4) or protein-losing enteropathy (PLE) (n = 5) after lateral tunnel-type Fontan operation. Patients with effusions had creation via coronary punch of two or three 3-mm defects; patients with PLE had creation of a large, 5-mm defect. One child with effusions and multisystem organ failure before fenestration died 7 weeks after surgery secondary to low cardiac output; the other 3 had resolution of effusions within 4 to 6 weeks. Of the 5 with PLE, 3 had normalization of serum proteins and resolution of symptoms at 2 to 6 weeks. The 2 failures had arterial saturations > 89% after surgery. Follow-up was from 25 to 30 months. Spontaneous closure of defects occurred in all 3 with effusions. No return of symptoms was noted in 2; however, the third reaccumulated effusions and has undergone refenestration with a large defect. All 3 patients with PLE have remained asymptomatic with patency of the fenestration (4 to 5 mm on echocardiography) and arterial saturation < or = 85% for > 2 years. CONCLUSIONS: Late surgical creation of fenestration results in resolution of morbidity after Fontan operation. Improvement is related to the degree of right-to-left shunt created.

Cardiac Catheterization↗
PubMed1997

Pulmonary AV malformations after superior cavopulmonary connection: resolution after inclusion of hepatic veins in the pulmonary circulation.

BACKGROUND: A high incidence of pulmonary arteriovenous malformations (PAVMs) has been reported in patients who have polysplenia and congenital heart disease after superior cavopulmonary anastomosis. Interruption of hepatic venous return to the pulmonary circulation is believed to potentiate the development of PAVMs. Surgical inclusion of hepatic flow in the pulmonary circulation may result in their resolution. METHODS: We reviewed 3 patients with congenital heart disease and polysplenia in whom PAVMs developed and who had subsequent hepatic vein inclusion in the pulmonary circulation. RESULTS: Patients underwent superior cavopulmonary connection at a median age of 8 months. The PAVMs were diagnosed at a median duration of 8 months after operation (arterial saturation <75% in room air). Hepatic venous flow was included in the pulmonary circulation at operation. Resolution of PAVMs occurred at a median duration of 7 months after operation (arterial saturation >90% in room air). CONCLUSIONS: Surgical inclusion of hepatic venous blood in the pulmonary circulation results in the resolution of PAVMs. Electively associating the hepatic veins with the pulmonary vasculature may prevent the development of PAVMs in patients who are at risk.

Arteriovenous Malformations↗
PubMed1997

Effect of surgical reconstruction on flow profiles in the aorta using magnetic resonance blood tagging.

BACKGROUND: The aorta that has undergone an aorta-pulmonary artery anastomosis may not exhibit the same velocity profile as the nonreconstructed aorta, whose velocity profile is thought to be uniform across the vessel diameter (plug flow). This may have an impact on fluid dynamics and will alter Doppler flow calculations. Our objective was to determine the impact of surgical reconstruction on the velocity and flow profiles of the reconstructed ascending and descending aorta. METHODS: Using a magnetic resonance imaging tagging technique that labels flowing blood (bolus tagging), we studied 22 patients (mean age, 8.6 +/- 4.7 years) who had had a Fontan procedure. A cine sequence labeled the blood and acquired the image after 20 ms in the middle of the ascending aorta and behind the left atrium in the descending aorta. The repetition time was 50 ms. RESULTS: The reconstructed ascending aorta displayed a velocity profile skewed anteriorly, whereas in the nonreconstructed aorta, the velocity profile was flat. Reconstructed aortas also displayed flows that were higher anteriorly, took a longer time to reach maximum velocity, and were less like "plug" flow than the nonreconstructed aorta. The descending aorta, regardless of whether aortic reconstruction was present, displayed velocity profiles (at various phases of systole) skewed posteriorly. CONCLUSIONS: The reconstructed aorta displays disturbed flow, and the velocities across the ascending aortic diameter are more varied than those in aortas without reconstruction and are skewed anteriorly. The descending aortic velocity profile in children is skewed posteriorly, regardless of whether aortic reconstruction is present. This information may help design and build a "better" aortic reconstruction.

Adolescent↗
PubMed1997

Cerebral oxygenation during cardiopulmonary bypass in children.

OBJECTIVE: Previous work has found cerebral oxygen extraction to decrease during hypothermic cardiopulmonary bypass in children. To elucidate cardiopulmonary bypass factors controlling cerebral oxygen extraction, we examined the effect of perfusate temperature, pump flow rate, and hematocrit value on cerebral hemoglobin-oxygen saturation as measured by near infrared spectroscopy. METHODS: Forty children less than 7 years of age scheduled for cardiac operations with continuous cardiopulmonary bypass were randomly assigned to warm bypass, hypothermic bypass, hypothermic low-flow bypass, or hypothermic low-hematocrit bypass. For warm bypass, arterial perfusate was 37 degrees C, hematocrit value 23%, and pump flow 150 ml/kg per minute. Hypothermic bypass differed from warm bypass only in initial perfusate temperature (22 degrees C); hypothermic low-flow bypass and low-hematocrit bypass differed from hypothermic bypass only in pump flow (75 ml/kg per minute) and hematocrit value (16%), respectively. Cerebral oxygen saturation was recorded before bypass (baseline), during bypass, and for 15 minutes after bypass had been discontinued. RESULTS: In the warm bypass group, cerebral oxygen saturation remained at baseline levels during and after bypass. In the hypothermic bypass group, cerebral oxygen saturation increased 20% +/- 2% during bypass cooling (p < 0.001), returned to baseline during bypass rewarming, and remained at baseline after bypass. In the hypothermic low-flow and hypothermic low-hematocrit bypass groups, cerebral oxygen saturation remained at baseline levels during bypass but increased 6% +/- 2% (p = 0.05) and 10% +/- 2% (p < 0.03), respectively, after bypass was discontinued. CONCLUSIONS: In children, cortical oxygen extraction is maintained during warm cardiopulmonary bypass at full flow and moderate hemodilution. Bypass cooling can decrease cortical oxygen extraction but requires a certain pump flow and hematocrit value to do so. Low-hematocrit hypothermic bypass and low-flow hypothermic bypass can also alter cortical oxygen extraction after discontinuation of cardiopulmonary bypass.

Brain↗
PubMed1997

Effect of BMI, insulin dose and number of injections on glycaemic control in insulin-using diabetic patients. Studygroup Diabetes Rijnmond (SDR).

BACKGROUND: Strict glucose control is essential to the prevention of diabetic complications. The level of glycaemic control in insulin-treated patients with diabetes mellitus (DM) in a routine clinical setting is not known. METHODS: In a cross-sectional survey comprising 8 hospitals in the Rijnmond area, The Netherlands, age, body mass index (BMI), insulin dose, number of injections, and HbA1c were scored in 712 patients with insulin-dependent DM (IDDM) and 462 patients with non-insulin-dependent DM (NIDDM). RESULTS: In IDDM and NIDDM patients, respectively, age (mean +/- SD) was 40 +/- 17 and 65 +/- 12 years, BMI was 24.1 +/- 3.5 and 27.3 +/- 4.1 kg/m2, daily insulin dose was 49 +/- 18 and 44 +/- 18 U (P < 0.001). Intensive therapy (> or = 4 injections or continuous subcutaneous insulin infusion) was used in 59% of IDDM and 13% of NIDDM patients. HbA1c below the upper normal limit was achieved in 11% of the patients, and within 20% above the upper normal limit in 37%. Obesity was positively associated with HbA1c in NIDDM patients (P < 0.01). A higher insulin dose was associated with higher HbA1c in both IDDM and NIDDM patients (P < 0.01). CONCLUSIONS: Good glycaemic control was established in 37% of our patients. Intensive insulin treatment and higher insulin dose did not improve glucose regulation. Obesity is a risk factor for poor glycaemic control.

Adult↗
PubMed1997

Tetralogy of Fallot with absent pulmonary valve: echocardiographic morphometric features of the right-sided structures and their relationship to presentation and outcome.

Respiratory symptoms in tetralogy of Fallot with absent pulmonary valve are believed to be due to bronchial compression secondary to dilated pulmonary arteries; however, not all patients are born compromised. Echocardiographic morphometry of the right-sided structures was investigated to determine the possible relationship between anatomy and clinical presentation. Twenty-five patients were identified, and 15 had preoperative echocardiograms. Patients were divided into two groups: those with respiratory distress (group I, n = 9) and those without (group II, n = 6). No difference was noted in branch pulmonary artery diameters between groups; however, the pulmonary valve/ aortic valve ratio, reflecting the dimension of the narrowest pathway from the right ventricle, was larger in group I (0.74 +/- 0.15 versus 0.60 +/- 0.07, p < 0.05). Pulmonary valve diameter correlated with main and right pulmonary artery diameters. We conclude that patients with tetralogy of Fallot with absent pulmonary valve and respiratory compromise have a greater pulmonary valve/aortic valve ratio but do not have greater dilatation of proximal branch pulmonary arteries. This suggests that the pathophysiology is not due solely to compression of the bronchi but is also related to the blood flow dynamics in the pulmonary vessels.

Adolescent↗
PubMed1997

Free and total insulin-like growth factor I (IGF-I), IGF-binding protein-1 (IGFBP-1), and IGFBP-3 and their relationships to the presence of diabetic retinopathy and glomerular hyperfiltration in insulin-dependent diabetes mellitus.

The existing literature on serum insulin-like growth factor I (IGF-I) levels in insulin-dependent diabetes mellitus (IDDM) is conflicting. Free IGF-I may have greater physiological and clinical relevance than total IGF-I. Recently, a validated method has been developed to measure free IGF-I levels in the circulation. Serum free and total IGF-I, IGF-binding protein-1 (IGFBP-1), and IGFBP-3 levels were measured in 56 insulin-treated IDDM patients and 52 healthy sex- and age-matched controls. Diabetic retinopathy was established by direct fundoscopy. In 54 IDDM patients, the glomerular filtration rate (GFR) and effective renal plasma flow were calculated from the clearance rate of [125I]iothalamate and [131I]iodohippurate sodium. Fasting free IGF-I, total IGF-I, and IGFBP-3 levels were significantly lower in IDDM patients than in age- and sex-matched healthy controls (free IGF-I, P < 0.005; total IGF-I, P < 0.001; IGFBP-3, P = 0.001), whereas IGFBP-1 levels were higher (P < 0.001). In IDDM subjects, decreases in free IGF-I, total IGF-I, and IGFBP-3 levels with age were observed (free IGF-I, r = -0.27 and P = 0.05; total IGF-I, r = -0.52 and P < 0.001; IGFBP-3, r = -0.37 and P = 0.005). Free IGF-I was inversely related to fasting glucose in IDDM subjects (r = -0.35; P = 0.01), whereas the relationship between total IGF-I and fasting glucose did not reach significance (r = -0.27; P = 0.06). Age-adjusted free IGF-I levels were significantly higher (P < 0.05) in IDDM subjects with retinopathy than in subjects without retinopathy after adjustment for age. Total IGF-I and IGFBP-3 levels were positively related to GFR (total IGF-I, r = 0.35 and P < 0.05; IGFBP-3, r = 0.28 and P < 0.05). Both of these differences lost significance after adjustment for age. Free IGF-I, total IGF-I, and IGFBP-3 levels were lower and IGFBP-1 levels were higher in insulin-treated IDDM subjects compared to those in age- and sex-matched controls. Free IGF-I, total IGF-I, and IGFBP-3 levels decreased significantly with age in IDDM subjects. Age-adjusted free IGF-I levels in subjects with diabetic retinopathy were higher than those in subjects without diabetic retinopathy. Total IGF-I and IGFBP-3 levels were positively related to GFR in IDDM subjects, but these relations were lost after adjustment for age. Measurement of serum free IGF-I levels in IDDM subjects did not have clear advantages compared to that of total IGF-I, IGFBP-1, and IGFBP-3 levels. Serum IGF-I and IGFBPs reflect their tissue concentrations to a various degree. Consequently, extrapolations concerning the pathogenetic role of the IGF/IGFBP system in the development of diabetic complications at the tissue level remain speculative.

Adolescent↗
PubMed1997

Effect of long-acting somatostatin analog (Somatulin) on renal hyperfiltration in patients with IDDM.

OBJECTIVE: To investigate whether long-acting somatostatin (SMS) can suppress renal hyperfiltration in patients with IDDM. RESEARCH DESIGN AND METHODS: A double-blind, randomized treatment of nine patients with IDDM was used. Selection criteria were renal hyperfiltration (glomerular filtration rate [GFR] > or = 129 ml.min-1.1.73 m2) and absence of hypertension and macroalbuminuria. Treatment was either with a long-acting SMS analog (Somatulin, 30 mg) or with placebo, given by intramuscular injections every 10 days for 9 months. GFR, effective renal plasma flow (ERPF), IGF-I, and 24-h growth hormone (GH) profiles were used as evaluation parameters. RESULTS: Five patients were randomized to Somatulin, four patients to placebo. One of the patients treated with Somatulin stopped after 3 months because of persistent abdominal discomfort after the injections. Somatulin treatment for 3 months lowered GFR and ERPF compared with placebo (P < 0.05). After 9 months, the differences were no longer significant. After 3 months, IGF-I concentrations were decreased in all Somatulin-treated patients. GH secretion tended to increase in the placebo group. CONCLUSIONS: The administration of long-acting Somatulin to patients with IDDM and renal hyperfiltration leads to only a temporary reduction of ERPF/GFR.

Adult↗
PubMed1996

Protein-losing enteropathy after Fontan operation: resolution after baffle fenestration.

A 4-year-old child with hypoplastic left heart syndrome and a 6-year-old child with tricuspid atresia had both undergone staged reconstructive operations culminating in a Fontan operation. Peripheral edema, ascites, and hypoalbuminemia refractory to dietary manipulation and steroid therapy developed in both patients. After hemodynamic assessment, each child underwent surgical creation of a 4.8-mm fenestration in the previously placed baffle that separated the systemic venous pathway from the pulmonary venous atrium. Peripheral edema and ascites promptly resolved and serum protein levels normalized within 2 weeks after operation. Systemic arterial saturation is 86% in each child, and both children remain clinically well with no evidence of protein-losing enteropathy on normal diets and without specific medical therapy.

Ascites↗
PubMed1996

Morphometric analysis of unbalanced common atrioventricular canal using two-dimensional echocardiography.

OBJECTIVES: This study was designed to define morphometric echocardiographic variables of unbalanced common atrioventricular canal (CAVC) that could aid in appropriate referral for surgical repair. BACKGROUND: Unbalanced CAVC has a high surgical mortality rate. This may be secondary to inappropriate referral of some patients for two-ventricle repair (closure of septal defects) instead of single-ventricle repair (Norwood palliation and Fontan operation). METHODS: The echocardiograms of 103 patients with CAVC were retrospectively reviewed. In the subcostal left anterior oblique view, the area of the atrioventricular (AV) valve aportioned over each ventricle was measured, and an AV valve index (AVVI) was calculated as left/right valve area. The ventricular cavity ratio between the two ventricles was estimated as left ventricular length times width divided by right ventricular length times width. These variables were correlated with surgical referral and outcome. RESULTS: Patients previously categorized as having balanced CAVC all had AVVI > 0.67 (n = 77). Of the patients with unbalanced CAVC (n = 26), 11 had ductal-dependent circulation and underwent Norwood palliation (AVVI 0.21 +/- 0.13, mean +/- SD), and 15 had two-ventricle repair (AVVI 0.51 +/- 0.12, p < 0.0001). Of these 15 patients, 9 have survived, with no difference in mean AVVI between survivors and nonsurvivors (0.52 +/- 0.11 versus 0.49 +/- 0.13, p = 0.72). For all 103 patients, AVVI correlated with ventricular cavity ratio. However, of the unbalanced CAVC group who underwent two-ventricle repair, three nonsurvivors had a discrepancy between AVVI and ventricular cavity ratio (low AVVI but normal ventricular size). A large ventricular septal defect was present in all six nonsurvivors but in only four of nine survivors (p < 0.05). CONCLUSIONS: Echocardiographic morphometry is useful in defining unbalance in CAVC. If AVVI is < 0.67 in the presence of a large ventricular septal defect, a single-ventricle approach to repair should be considered.

Child, Preschool↗
PubMed1996

Growth hormone responses to growth hormone-releasing hormone and clonidine in patients with type I diabetes and in normal controls: effect of age, body mass index and sex.

OBJECTIVE: Increased plasma concentrations of GH and increased GH responses to provocative stimuli are reported in patients with poorly controlled type I diabetes and are suggested to be related to complications. Our aim was to investigate GH concentrations in moderately controlled patients. PATIENTS AND MEASUREMENTS: We have investigated IGF-I concentrations and fasting GH concentrations and the response to 1 microgram/kg body weight GH-releasing hormone (GHRH) intravenously and/or to 150 micrograms clonidine intravenously in 77 moderately controlled patients with type I diabetes and in 46 healthy controls. RESULTS: Median HbA1c in the patients was 8.5% (upper level of normal 6.3%). Fasting GH and GH concentrations after the administration of GHRH were not significantly different in patients with type I diabetes compared with normal controls. Fasting and stimulated GH concentrations after the administration of clonidine were significantly higher in the patients, but this could be explained by their lower age and body mass index compared with controls. In controls but not in patients there was a negative correlation between GH and glucose concentrations. IGF-I was significantly lower in patients with diabetes than in controls, even after correction for age, body mass index and sex. CONCLUSIONS: Patients with moderately controlled type I diabetes mellitus have normal baseline and stimulated GH concentrations after the administration of GHRH or clonidine compared with healthy controls, when corrected for age, body mass index and sex. However, these 'normal' GH concentrations must be considered inappropriately high in view of the hyperglycaemia in these patients. The low plasma IGF-I concentrations might be responsible for the GH over-production.

Adolescent↗
PubMed1996

Hypertriglyceridemia enhances monocyte binding to endothelial cells in NIDDM.

OBJECTIVE: The mechanisms by which diabetes leads to rapidly progressive atherosclerosis are not fully understood. Adherence of monocytes to the arterial wall is an early event in the development of atherosclerotic lesions. RESEARCH DESIGN AND METHODS: The binding of freshly isolated monocytes from patients with NIDDM, IDDM, and healthy control subjects to a monolayer of endothelial cells obtained from human umbilical vein was investigated. RESULTS: Endothelial adherence of monocytes from normolipidemic patients with IDDM (15.8 +/- 4.5%) or NIDDM (16.9 +/- 4.6%) was comparable to that of monocytes from a control population (15.3 +/- 3.5%). In patients with NIDDM with a serum triglyceride concentration > 2.5 mmol/l, the percentage of cells that adhere to endothelial cells in vitro was significantly increased (23.3 +/- 3.1%). Glycemic control did not correlate with monocyte adherence. The presence of symptomatic atherosclerotic disease, age, or sex was not associated with a change in monocyte binding in vitro. CONCLUSIONS: The results suggest that in NIDDM hypertriglyceridemia should be treated to reduce the high risk for atherosclerosis.

Adult↗
PubMed1996

Early reduction of the volume work of the single ventricle: the hemi-Fontan operation.

BACKGROUND: In hearts with a functional single ventricle, cavity volume and myocardial muscle mass increase as a consequence of the excessive volume work associated with parallel pulmonary and systemic circulations. The hemi-Fontan operation was conceived as a means of accomplishing early reduction of the volume work of the single ventricle. METHODS: All patients presenting in infancy with single-ventricle physiology were managed by early hemi-Fontan operation in anticipation of a subsequent completion Fontan operation. Between May 1989 and August 1995, 400 patients less than 2 years of age underwent hemi-Fontan operations. Mean age at operation was 8.5 months (range, 2 months to 24 months). The hemi-Fontan operation included association of superior vena(e) cava(e) with the branch pulmonary arteries, augmentation of the central pulmonary arteries, occlusion of the inflow of the superior vena cava into the right atrium, and elimination of other sources of pulmonary blood flow. RESULTS: Operative mortality ( < 30 days) was 31 of 400 patients (7.8%). For the last 200 patients, operative mortality was 8 of 200 (4.0%). Younger age at operation was not an independent risk factor for operative mortality. Urgent operation in the presence of a hemodynamic burden requiring concomitant procedures was associated with increased mortality. CONCLUSIONS: The hemi-Fontan operation can be accomplished with low operative mortality in young patients, achieving early reduction of the volume work of the single-ventricle heart.

Age Factors↗
PubMed1995

Interrupted aortic arch. Impact of subaortic stenosis on management and outcome.

Interrupted aortic arch (IAA) is often related developmentally to subaortic obstruction (SAO). When severe, SAO must be addressed in surgical management of IAA. From 1990 to 1993, 25 neonates presented for initial surgical management of IAA complexes. Associated lesions were ventricular septal defect (VSD) with or without atrial septal defect (19 patients), truncus arteriosus (3 patients), tricuspid atresia with transposition of the great arteries (1 patient), aortic atresia with VSD (1 patient), and d-transposition of the great arteries with VSD (1 patient). Overall hospital mortality was 20% (five deaths). One death was related to sepsis and two to sudden hemodynamic decompensation (a 2-kg premature infant after arch repair and VSD closure and a neonate with IAA-truncus arteriosus after arch repair and truncus repair with aortic root replacement). Two deaths were related to low cardiac output in patients with severe subaortic narrowing (< 3 mm by two-dimensional echocardiography), which was not addressed surgically. Of 10 additional patients judged preoperatively to have severe SAO, 1 underwent resection of the infundibular septum together with VSD closure and arch reconstruction, and 9 underwent a modification of Norwood's operation with arch reconstruction and proximal pulmonary artery to aortic anastomosis (7 with systemic to pulmonary artery shunts and 2 with right ventricle to pulmonary artery outflow tract reconstruction). One patient died 2 months after surgery of staphylococcal sepsis. All 9 others were discharged well. Subaortic narrowing is a physiologically important element of IAA complexes. When SAO is severe, satisfactory initial palliation can be achieved by a modification of Norwood's operation.

Aorta, Thoracic↗