Detection of "pathologic" prosthetic valve stenosis via exercise Doppler echocardiography

To detect borderline mitral valve dysfunction in asymptomatic patients, with Björk-Shiley valves, we studied the patients' hemodynamics at rest and during exercise by Doppler echocardiography. Supine bicycle exercise was performed by 65 patients. The patients were divided into two groups according to the measurements of the exercise Doppler echocardiography: a normally functioning group (n = 45) and a borderline group (n = 20). The valve area at rest was 2.0 +/- 0.6, 2.1 +/- 0.7, and 2.3 +/- 0.5 cm2 with valve sizes of 25, 27, and 29 mm, respectively, in the normal group and 1.9 +/- 0.5, 1.9 +/- 0.4, and 2.1 +/- 0.3 cm2 in the borderline group. The mitral valve area did not significantly change with exercise in either group. In the normal group, peak gradients increased from 9.9 +/- 3.5, 9.7 +/- 1.1, and 9.5 +/- 1.6 mmHg with valve sizes of 25, 27, and 29 mm, respectively, at rest to 15.1 +/- 3.1, 14.0 +/- 3.3, and 14.8 +/- 2.6 mmHg with exercise. Mean gradients increased from 5.2 +/- 1.2, 5.9 +/- 1.3, and 5.8 +/- 1.8 mmHg with valve sizes of 25, 27, and 29 mm, respectively, at rest to 8.0 +/- 2.5, 9.1 +/- 2.0, and 8.8 +/- 1.6 mmHg with exercise. In the borderline group, peak gradients increased from 10.5 +/- 3.1, 10.1 +/- 2.1, and 10.8 +/- 1.7 mmHg with valve sizes of 25, 27, and 29 mm, respectively, at rest to 24.5 +/- 4.2, 23.6 +/- 4.4, and 22.4 +/- 3.2 mmHg with exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of bidisomide (SC-40230), a new class I antiarrhythmic agent, on ventricular arrhythmias induced by coronary artery occlusion and reperfusion in anesthetized rats; comparison with mexiletine and disopyramide

We investigated the antiarrhythmic effects of bidisomide (SC-40230), a new class I antiarrhythmic drug, in early-phase ventricular arrhythmias induced by coronary artery occlusion and reperfusion in anesthetized rats. The effects of bidisomide were compared with those of mexiletine (MXT) and disopyramide (DSP), established class I antiarrhythmic drugs. Drugs were administered intravenously, 5 min before induction of coronary occlusion. Bidisomide (5 mg/kg) reduced the number of premature ventricular complexes and the incidence of ventricular tachycardia and ventricular fibrillation similarly to MXT and DSP in rats with ventricular arrhythmias induced by coronary artery occlusion. In rats with ventricular arrhythmias induced by coronary artery reperfusion following a 5-min coronary occlusion, the antiarrhythmic effects of 5 mg/kg of bidisomide were similar to those of the same doses of MXT and DSP. All three drugs significantly slowed the heart rate. Our results suggest that bidisomide may effectively reduce the severity of life-threatening ventricular arrhythmias that occur during acute coronary syndrome.

Surgical indications and treatment of mitral valve disease associated with secundum atrial septal defect with special reference to left ventricular geometry and function

There are few reports that discussed surgical indications and selection of surgical procedures for secundum atrial septal defect (ASD) associated with mitral valve disease from the viewpoint of left ventricular geometry and function. Our study on 20 patients (6 patients with ASD and MS, 14 patients with ASD and MR) indicated that adult patients with ASD and MS can be treated surgically even when left ventricular end-diastolic volume index (LVEDVI) is as low as 35 ml/m2 (one third of the normal level). Left ventricular wall movement returned to normal one year following surgery. Therefore, rather than myocardial impairment, right ventricular volume load disturbing left ventricular dilatation would be the more likely cause of diminished left ventricular function before surgery in the ASD and MS group. In both groups, two patients who initially had undergone mitral valve replacement died from low output syndrome because of the mismatch between the left ventricular volume and the prosthesis used, whereas there were no deaths in the patients who had mitral valve repair. For this reason, mitral valve repair is the treatment of choice for patients with both secundum ASD and mitral valve disease. When valve replacement is the only alternative, selection of prosthetic valves and maintenance of cardiac output by temporary cardiac pacing are important considerations. A low profile valve with a larger orifice area should be selected to avoid the mismatch between a left ventricular volume and a prosthesis.

Biosynthesis of mucin derived from a 60-kDa precursor protein in the human stomach

We studied the biosynthesis of mucin in the human stomach using an anti-mucin core peptide monoclonal antibody, 3G12. Human stomach mucosa was labeled with [35S]methionine, and chased for 3 h. An approximately 60-kDa subunit of human gastric mucin precursor protein was detected in the intracellular product. Under nonreducing conditions, dimer, trimer, and tetramer mucin precursor protein (120, 180, 240 kDa) were detected. Treatment with tunicamycin or endo-beta-N-acetylglucosaminidase H had no effect on the 60-kDa subunit and its oligomers. Extracellular products contained only the high molecular weight mucin, and the secretion was not affected by tunicamycin. By treatment with monensin or brefeldin A, the mature mucin was not secreted extracellularly. These findings suggested that a 60-kDa subunit of the mucin precursor protein was biosynthesized into mature mucin after oligomerization to tetramers, and that neither the oligomerization nor the intracellular transport of the mucin in the human stomach was associated with N-glycosylation.

Biosynthesis and secretion of mucin-related products in Hs746T gastric cancer cells

We have previously studied the biosynthesis and secretion of mucin in the normal human stomach and reported that the tetramer of the 60-kDa subunit of mucin core protein was synthesized and highly glycosylated, and that only high molecular weight mucin was secreted. In this study, we investigated the mucin-related products of a gastric cancer cell line (Hs746T). Analysis of intracellular and extracellular products immunoprecipitated with an anti-apomucin monoclonal antibody revealed that a 110-kDa protein, the dimer of the 55-kDa subunit, was synthesized and secreted. Tunicamycin treatment inhibited the secretion of the 110-kDa protein. These findings suggest that N-glycosylation may be involved in the secretory mechanism of the mucin-related product.

Enhancement in gastric mucosal laminin receptor expression with ulcer healing by sucralfate

The expression of gastric mucosal laminin receptor during chronic ulcer healing in the presence of sucralfate treatment was investigated. Rats with induced gastric ulcers were treated twice daily for 20 consecutive days either with sucralfate at 100mg/kg or vehicle, and at different stages of treatment used for gastric mucosal laminin receptor quantitation. The assays revealed that accelerated ulcer healing (8 days) in the presence of sucralfate was accompanied by a significant enhancement in the laminin receptor expression. A 2.8-fold increase in the receptor expression over that of controls occurred by the 3rd day of sucralfate treatment, reached a maximum of 3.1-fold increase by the 7th day and remained elevated even after 20 days of treatment. The results attest to the ability of sucralfate to stimulate and promote the events associated with gastric mucosal integrity restoration.

Nonpeptide ligands for human gamma delta T cells

gamma delta T cells respond to a variety of microbial pathogens and transformed cells. Their limited receptor repertoire and activation by mycobacterial antigens resistant to proteases suggest that they may recognize nonpeptide antigens. We have tested a variety of nonpeptide molecules for stimulation of human gamma delta T cells. Synthetic alkyl phosphates, particularly monoethyl phosphate (MEP), selectively activated gamma delta T cells and stimulated their proliferation in vitro. All gamma delta T cells stimulated by MEP expressed V gamma 2/V delta 2 receptors. The purified natural ligand of mycobacteria is chemically similar to, though distinct from, MEP and contains a phosphate residue that is critical for biological activity. Recognition and expansion of a specific T-cell receptor-bearing population to non-peptide ligands is unprecedented among T cells. We suggest that MEP mimics small natural ligands capable of expanding one subset of gamma delta T cells and that this recognition of nonpeptide antigens may play an important role in human immunity to pathogens.

Micropathologic changes of pars tensa in children with otitis media with effusion

Clinical studies have supported a relationship between otitis media with effusion in children and chronic otitis media in adults. Although clinical studies are numerous, relatively little is known about the histopathologic changes of the tympanic membrane in otitis media with effusion. Tympanic membranes were taken from the intermediate zone of the anteroinferior quadrant of the tympanic membrane during surgery for placement of tympanostomy tubes in 30 children (age range, 4 to 10 years) who did not show any improvement after 3 months of conservative treatment for otitis media with effusion. Control specimens were taken from normal temporal bones at autopsy. All specimens were observed with light and electron microscopy. Histologic degeneration of the tympanic membrane of patients with otitis media with effusion occurred most often in the lamina propria and the submucosal layer. There was an increase in the thickness of the tympanic membrane as a result of edema and fibrosis of the submucosal layer. A decrease in the thickness of the outer and inner fibrous layers occurred in the lamina propria. The histopathologic changes observed in the lamina propria may result in a change in the elastic properties of the tympanic membrane.

Criteria to detect mitral prosthetic valve dysfunction via continuous wave Doppler echocardiography

To detect the diagnostic criteria for mitral prosthetic valve dysfunction, Doppler echocardiography was used to assess valve function following mitral valve replacement in 100 patients [50 with St. Jude Medical (SJM) valves, 50 with Björk-Shiley (B-S) valves]. Mitral valve area (MVA) was calculated by dividing a constant of 220 by pressure half time (PHT) measured via Doppler technique [220/PHT]. The relationship of MVA to left ventricular function, geometric valve area (GVA) of the prosthetic valve, body surface area (BSA), and maximum disc-opening angle (maxOA) were assessed. In the SJM valves, MVA significantly correlated with valve area index (GVA/BSA). The % area index [(MVA/valve area index) x 100] was 100.2 +/- 12.8% on the average and no patients with the SJM valve showed the %area index of less than 73%. There was no incidence of valve dysfunction in the SJM valves. We concluded from these results that if the % area index is less than 73% (mean -2SD), the SJM valve dysfunction should be diagnosed. When the B-S valves were examined, there were 19 patients in whom the maximum opening angle had decreased to under 58 degrees. These patients also had decreased MVA and % area index. Evaluation of the relationship between the maximum opening angle and the % area index revealed that the patients in whom the maximum opening angle had diminished to under 50 degrees had low % area index (of less than 70%).(ABSTRACT TRUNCATED AT 250 WORDS)

The clinical and pathological features of isolated aortic regurgitation in relation to its etiology

Chronic isolated aortic regurgitation (AR) caused by degenerative, rheumatic, and Marfan etiologies were compared in a study of 87 patients. There were three hospital deaths in the Marfan group, but none in the rheumatic and degenerative groups. The late postoperative survival rates at 5 and 10 years were 98% and 94%, respectively, in the rheumatic group; 84% and 84%, respectively, in the degenerative group; and 85% and 78%, respectively, in the Marfan group. An analysis of the late complications disclosed a higher incidence of aortic dissection and paravalvular leakage in the degenerative and Marfan groups than in the rheumatic group. In the degenerative group, 4 of the 32 patients developed acute aortic dissection within 3 years following aortic valve replacement. The aortic root diameter in these 4 patients was more than 40 mm at the time of surgery, whereas it was less than 40 mm in the remaining 28 patients. In conclusion, considering the progressive nature of myxomatous degeneration, patients with a severely dilated aortic root diameter should be monitored carefully with echocardiography after surgery.

[Changes of arterial CO2 (PaCO2) and urine output by carbon dioxide insufflation of the peritoneal cavity during laparoscopic cholecystectomy]

We studied on the effects of carbon dioxide insufflation during laparoscopic cholecystectomy on the arterial blood gas analysis and urine output. Intra-abdominal pressure was increased up to either 10cmH2O or 15cmH2O, and we compared the PaCO2 values before and during insufflation. Both increase of PaCO2 and decrease in pH were larger in intra-abdominal pressure of 15cmH2O than 10cmH2O. In the intra-abdominal pressure 15cmH2O group, the increase of PaCO2 by CO2 peritoneal insufflation was significantly larger in operative time of more than 60 minutes group than in less than 60 minutes group, but no significant changes were observed in 10cmH2O group. In the group of obesity index of more than 120, elevation levels of PaCO2 by CO2 insufflation were significant, but in the group of less than 120 no significant elevation were observed. The tendency that the urine output during operation was decreased as increase of intra-abdominal pressure or operative time, but the obesity had no definite effects on urine output. Insufflation of the abdomen with CO2 caused large changes in PaCO2 or pH in the patients with a previous history of major cardiopulmonary disorder. It was shown that the low insufflation pressure and short operative time is good for the maintenance of normal physiological state.

[The indication of operative procedure for a metastatic spine tumor: a scoring system for the preoperative evaluation of the prognosis]

Since 1987, the operative procedure for a metastatic spine tumor has been decided on the basis of a scoring system for the preoperative evaluation of prognosis. Six parameters which affected the prognosis were employed in this assessment: 1) the general condition, 2) the number of extraspinal bone metastases, 3) the number of metastases in the vertebral body, 4) incidence of metastasis to a major internal organ (lungs, liver, kidneys, and/or brain), 5) the primary site of the cancer, and 6) the severity of spinal cord palsy. Each parameter was scored from 0 (high risk) to 2 (low risk) points. An excisional operation was performed when the total score was above 9 points, while a palliative operation was indicated for those who scored under 5 points. This assessment system was evaluated for 113 cases who had undergone surgery according to this criterion. The survival period of 92.3% of patients who scored less than 6 points was less than 6 months, while that of 78.3% of patients who scored more than 8 points was more than one year. The total score obtained for each patient correlated with the prognosis, and was valuable in predicting prognosis for a lesion at any stage. In conclusion, it was appropriate to indicate the operative procedure for a metastatic spine tumor according to this scoring system.

cDNA cloning of monodehydroascorbate radical reductase from cucumber: a high degree of homology in terms of amino acid sequence between this enzyme and bacterial flavoenzymes

The FAD-enzyme monodehydroascorbate (MDA) reductase catalyzes the regeneration of ascorbate from the MDA radical using NAD(P)H as the electron donor [Hossain and Asada (1985) J. Biol. Chem. 260: 12920]. We cloned a cDNA of MDA reductase from cucumber seedlings and deduced its entire sequence of amino acid residues. The cDNA library from cucumber seedlings in the expression vector was screened with an antiserum against cucumber MDA reductase. Inserts from three immunoscreened clones hybridized with two oligonucleotide probes designed on the basis of the sequences of two peptide fragments from the cucumber enzyme. The nucleotide sequences of these three clones were determined and the longest one contained an open reading frame of 1,302 bp in length. The molecular mass of the translation product predicted from the open reading frame was 47 kDa, the same as that determined for the purified enzyme. The amino acid sequences determined from fragments of lysyl endopeptidase-digested MDA reductase could be aligned with that deduced from the open reading frame, although substitution of several residues was apparent. Thus, the open reading frame encoded an isozyme of MDA reductase of cucumber different from the purified enzyme. MDA reductase has the FAD- and NAD(P)H-binding domains of flavoproteins but shares only limited homology in terms of amino acid sequence with flavoenzymes from eukaryotes.

Cytokeratin patterns of normal middle ear epithelia in humans, cats, and chinchillas

We describe the cytokeratin patterns of epithelia from the tympanic orifice, tympanic cavity, and mastoid cavity of humans, cats, and chinchillas, and compare these findings with those of tracheal epithelium and external canal epidermis. Our findings are as follows: 1) middle ear epithelium from all locations demonstrates some type of cytokeratin staining, 2) broad-spectrum cytokeratin antibodies stain epithelia of middle ear cleft, tracheal epithelium, and external canal epidermis in all species, 3) specific cytokeratin antibodies reveal species-related differences in middle ear and tracheal epithelia, 4) middle ear and tracheal epithelia usually have the same pattern, and 5) none of the monospecific cytokeratin antibodies have a positive reaction with external canal epidermis. These findings suggest that the cytokeratin patterns of middle ear epithelium are useful in studying the hyperplastic and metaplastic changes in otitis media; however, caution must be exercised when making interspecies comparisons.

Different subsets of CNS neurons express different glycosaminoglycan epitopes on large perineuronal proteoglycans

Proteoglycans are known to occur in the central nervous tissue, but their function is not well understood. We made a biochemical study of four perineuronal antigens on different subsets of rat brain neurons and found that three antigens recognized by antibodies against glycosaminoglycan epitopes were large proteoglycans. Molecular masses estimated by immunoblotting were 700 kDa for 473, 376 and 1B5 antigens and 600 kDa for the 374 antigen. Reactivities of the antigens on immunoblots to monoclonal antibodies (MAbs) 473 and 376 were lost, and that to MAb 1B5 uncovered, after chondroitinase ABC treatment as in the brain sections. The elution profiles from ion-exchange and gel-filtration column chromatography of 473, 376 and 1B5 antigens were quite similar, but those of 374 antigen were slightly different. The immunoaffinity-purified 473 antigen migrated at 700 kDa on sodium dodecylsulfate gel electrophoresis, and chondroitinase ABC treatment decreased the molecular mass to 600 kDa. The 473 antigen was recognized by MAbs 376 and 1B5 although these MAbs also reacted with 473-negative 700 kDa molecules. These results suggest that neuronal subset-specific glycosylation may occur on the 700 kDa proteoglycans, and that the glycosaminoglycan structures may be involved in the pericellular diversity of CNS neurons.

[A case of congenital atrial flutter associated with atrial septal defect]

We report the case of a 8-month-old boy with atrial septal defect associated with congenital atrial flutter. He was operated on for ASD successfully. Atrial flutter in infants has been reported to be uncommon and to have a poor prognosis when associated with underlying cardiac disease. Therefore, early surgical intervention may improve the prognosis.

Evaluation of clinical lumbar instability using the treadmill

The physical signs of lumbar instability have not yet been clearly defined. Furthermore, they do not always coincide with the abnormal movement on flexion-extension radiographs. Thus, the treadmill was used to evaluate clinical lumbar instability. The subjects were 82 patients with degenerative lumbar disease aggravated by walking or daily physical activities. The reproduction and provocation of low-back pain or pain in the lower extremities was examined during walking on a treadmill. The responses of the reproduction and provocation of the symptoms were divided into four grades. Fifteen cases were examined again using a treadmill after body casting to determine the indication for fusion surgery. As a result, the responses in the reproduction or provocation test using a treadmill manifest more dominant reflection of clinical symptoms suggesting clinical lumbar instability than the existence of the abnormal movement on flexion-extension radiographs. Reexamination after body casting was useful to determine the indications of fusion operations. The reproduction or provocation test using a treadmill was implied as a possible functional evaluation method of clinical lumbar instability.

Introduction of functional groups onto the surface of polyethylene for protein immobilization

Amino and carboxyl groups could be introduced onto the surface of high-density polyethylene film by utilizing graft polymerization of acrylamide and the subsequent Hofmann degradation and alkaline hydrolysis of grafted polyacrylamide. Graft polymerization was carried out by immersing an argon-plasma treated film in an aqueous solution of the monomer, followed by heating after degassing the monomer/film mixture. The surface density of these functional groups could be increased up to 10(-7) mol/cm2. The surfaces having amino and carboxyl groups exhibited positive and negative zeta potentials, respectively, when contacted with KCl aqueous solution. Both of the functional groups introduced onto the polyethylene surface were found to be utilizable for covalent immobilization of protein using carbodiimide for the carboxylic group or mediators such as glutaraldehyde and ethylene glycol diglycidyl ether for the amino group.

[A case of partial anomalous pulmonary venous connection to the high superior vena cava with intact atrial septum]

A 16-year-old female with partial anomalous pulmonary venous connection to the high superior vena cava underwent a successful correction using only autologous pericardium. Right upper pulmonary venous blood returned to the left atrium via the superior vena cava and the constructed atrial septal defect. The right atrium received blood from the brachiocephalic vein through the conduit. The azygos vein was not identified. Post-operative examination revealed that there were no pressure gradients across the superior vena cava and the conduit. She was discharged from the hospital on the 14th post-operative day.

[Perioperative insertion of peritoneal dialysis catheter]

Silicon rubber peritoneal dialysis catheter (Tenkoff) was inserted perioperatively in neonates undergoing cardiac surgery and also in those patients in whom right-sided heart failure may occur. This method is easy and safe even in neonates. Post operative excessive fluid retention could be avoided using this method.

Criteria to select proper valve prosthesis for aortic valve replacement. Comparative assessment of various valve prostheses via continuous wave Doppler echocardiography

Continuous wave Doppler echocardiography was used to measure pressure gradients (PG) across various aortic valve prostheses [St. Jude Medical (SJM) valve: 55 cases; Björk-Shiley (B-S) valve: 18 cases; Lillehei-Kaster (L-K) valve: 25 cases; and Omniscience (O-S) valve: 49 cases]. Disc-opening angles of the L-K and O-S valves were measured via cineradiography. Pressure gradient across the SJM valve tended to be low. Increase in pressure gradients during exercise tended to be greater in the small valves. There was a significant correlation between the valve area index (VAI) and pressure gradients in the SJM valve (PG = 85.3-40.2 x VAI, r = -0.71, p < 0.005) and in the B-S valve (PG = 64.6-23.3 x VAI, r = -0.89, p < 0.025). To keep pressure gradients below 20 mmHg, SJM valve #23 and B-S valve #25 should be selected for patients with a body surface area of 1.3-1.7 m2. In the L-K and O-S valves, there was no significant correlation between VAI and PG, likely because the disc-opening angles of these valves were suboptimal--averaging 57 degrees in the L-K valve and 47 degrees in the O-S valve. None of the patients with SJM or B-S valves had pressure gradients of 50 mmHg or above. However, pressure gradients exceeded 50 mmHg in 7 cases with the L-K valve (28%) and 10 with the O-S valve (20%), suggesting the necessity of careful follow-up in patients with these prostheses.

Major histocompatibility antigen-restricted cytotoxicity in inflammatory bowel disease

BACKGROUND

The role of cytotoxicity mediated by peripheral blood mononuclear cells for colonic epithelial cells in inflammatory bowel disease (IBD) is still controversial. To clarify it, we studied major histocompatibility antigen (MHC)-restricted T cell-mediated cytotoxicity (CTL).

METHODS

Cytotoxicity was measured by 51Cr release from colonic cells after the 6-hour incubation with peripheral blood mononuclear cells in 11 IBD patients (6 with Crohn's disease and 5 with ulcerative colitis).

RESULTS

CTL activity (E/T ratio = 200:1 or 100:1) for autologous target cells was significantly increased (22%-40%) in 5 of 6 CD and 4 of 5 UC patients (22%-64%) compared with that for allogeneic target cells. The increase in CTL activity was mainly inhibited by anti-MHC class I and CD8 monoclonal antibodies (50 micrograms/mL), while it was partially inhibited by anti-MHC class II or CD4 antibodies in some patients. Complement-mediated depletion of CD2+ cells also significantly decreased CTL activity.

CONCLUSIONS

The results indicate that MHC-restricted T cell cytotoxicity may play a role in mucosal damage in some patients of IBD.

Effect of short-term administration of dexamethasone on canine antral gastrin gene expression

The acute effect of corticosteroids on the release and biosynthesis of gastrin still remains unclear. We report the effect of short-term administration of dexamethasone on the antral gastrin gene expression and gastrin levels in 6 dogs, which were treated with dexamethasone (1.5 mg/kg, i.m. daily) for 3 days. One day after treatment, gastrin mRNA levels increased (152 +/- 14%), but serum and tissue gastrin showed no significant changes. With 2 and 3 days of dexamethasone treatment, gastrin mRNA (2 days: 163 +/- 28%, 3 days: 170 +/- 22%), serum gastrin (2 days: from 94 +/- 12 to 168 +/- 23 pg/ml, 3 days: to 180 +/- 16 pg/ml) and tissue gastrin concentration (2 days: from 480 +/- 32 to 664 +/- 31 pg/mg tissue protein, 3 days: to 708 +/- 45 pg/mg tissue protein) significantly increased. However, gastrin mRNA levels were not increased even after 1 day culture of canine antral tissue with dexamethasone in vitro. These findings suggest that short-term administration of corticosteroid may increase the canine gastrin gene expression in vivo by an unknown pathway.

Tetralogy of Fallot: favorable outcome of nonneonatal transatrial, transpulmonary repair

This report describes our experience with 366 patients who had a transatrial, transpulmonary repair of tetralogy of Fallot between December 1980 and December 1991. Included in this group are patients with tetralogy of Fallot plus atrioventricular septal defect as well as patients displaying all degrees of aortic override (in the presence of subaortic ventricular septal defect and right ventricular outflow tract obstruction). Median age was 15.3 months and median weight, 12.3 kg. Of the 366 patients, 72% required a pericardial patch to reconstruct the main pulmonary artery or right ventricular outflow tract. Serious coronary anomalies were seen in 11 patients, without influencing surgical approach. There were two hospital deaths (0.5%; 70% confidence limits, 0.2% to 1.2%). Actuarial survival was 97.5% at 42 months (95% confidence limits, 95% to 99%) reflecting four late deaths over 1,129 patient-years of follow-up. Postoperative cardiac catheterization studies were performed in 61 patients at a mean follow-up interval of 23 months. Mean right ventricular/left ventricular systolic pressure ratio after repair was 0.46 (standard deviation, 0.28), and mean gradient across the right ventricular outflow tract was 15 mm Hg (standard deviation, 24 mm Hg). Actuarial freedom from reoperation for any reason has been 95% (95% confidence limits, 92% to 97%) at 5-year and 10-year follow-up. These early and medium-term results encourage us to continue with transatrial, transpulmonary repair of tetralogy of Fallot. We believe that this approach has an operative risk similar to or lower than transventricular repair, and that it will result in better preservation of right ventricular function in the long term.

Repair of hypoplastic or interrupted aortic arch via sternotomy

Herein we describe our experience with repair of interrupted aortic arch and coarctation plus hypoplastic aortic arch in 55 consecutive infants (1984 to 1990). Median age at operation was 6 days and median weight 3.1 kg. Associated severe intracardiac anomalies were the rule. All patients had significant congestive cardiac failure, and the majority required prostaglandin E1 resuscitation and inotropic support (with or without ventilation) before the operation. All operations were performed via sternotomy with core cooling and circulatory arrest. Isolated myocardial perfusion was used in 13 patients during arch repair. A complete intracardiac (biventricular) repair was performed except in patients expected to require a Fontan operation as definitive treatment. The operative mortality overall was 14.5% (confidence limits 10% to 22%). For arch repair plus biventricular intracardiac repair, the operative mortality was 9% (confidence limits 5% to 15%), and for arch repair plus palliative intracardiac repair, 40% (confidence limits 22% to 60%). The mortality in the isolated myocardial perfusion group was 0% (confidence limits 0% to 14%), which may be related to reduced myocardial ischemic time (p less than 0.05). Actuarial survival was 75% (confidence limits 65% to 83%) at 12 months, with no subsequent deaths over 1294 patient-months (mean 28 months) of follow-up. Actuarial freedom from recurrent arch obstruction was 69% (confidence limits 48% to 85%) at 46 months' follow-up. Primary repair of interrupted aortic arch and coarctation plus hypoplastic arch compares favorably with a staged approach and is recommended even when complex intracardiac anatomy is present.