Cardiovascular magnetic resonance parameters associated with early transplant-free survival in children with small left hearts following conversion from a univentricular to biventricular circulation

BACKGROUND

We sought to identify cardiovascular magnetic resonance (CMR) parameters associated with successful univentricular to biventricular conversion in patients with small left hearts.

METHODS

Patients with small left heart structures and a univentricular circulation who underwent CMR prior to biventricular conversion were retrospectively identified and divided into 2 anatomic groups: 1) borderline hypoplastic left heart structures (BHLHS), and 2) right-dominant atrioventricular canal (RDAVC). The primary outcome variable was transplant-free survival with a biventricular circulation.

RESULTS

In the BHLHS group (n = 22), 16 patients (73%) survived with a biventricular circulation over a median follow-up of 40 months (4-84). Survival was associated with a larger CMR left ventricular (LV) end-diastolic volume (EDV) (p = 0.001), higher LV-to-right ventricle (RV) stroke volume ratio (p < 0.001), and higher mitral-to-tricuspid inflow ratio (p = 0.04). For predicting biventricular survival, the addition of CMR threshold values to echocardiographic LV EDV improved sensitivity from 75% to 93% while maintaining specificity at 100%. In the RDAVC group (n = 10), 9 patients (90%) survived with a biventricular circulation over a median follow-up of 29 months (3-51). The minimum CMR values were a LV EDV of 22 ml/m² and a LV-to-RV stroke volume ratio of 0.19.

CONCLUSIONS

In BHLHS patients, a larger LV EDV, LV-to-RV stroke volume ratio, and mitral-to-tricuspid inflow ratio were associated with successful biventricular conversion. The addition of CMR parameters to echocardiographic measurements improved the sensitivity for predicting successful conversion. In RDAVC patients, the high success rate precluded discriminant analysis, but a range of CMR parameters permitting biventricular conversion were identified.

Metabolites of the L-arginine-NO pathway in patients with left-to-right shunt

OBJECTIVES

The endogenous production of metabolites of the L-arginine-NO pathway has been found to be altered in patients with left-to-right shunt and pulmonary hypertension. The objective of this study was to analyze the influence of age and of the magnitude of the left-to-right shunt on plasma levels of L-arginine, cyclic guanosine monophosphate (cGMP), nitrite and nitrate in children and young adults presenting with left-to-right shunt.

METHODS

Twenty-nine patients with ventricular septal defect (n=18), atrial septal defect (n=6) and atrioventricular canal (n=5) were assigned to group I when the ratio of pulmonary to systemic blood flow (Qp/Qs) was less than 1.5 (n=10) and to group II when Qp/Qs > or = 1.5 (n=19). At cardiac catheterization blood samples were taken from the pulmonary vein or left ventricle. In 33 controls peripheral venous blood was obtained. cGMP levels were determined by radioimmunoassay, L-arginine, nitrite and nitrate by high performance liquid chromatography (HPLC).

RESULTS

L-arginine plasma levels were lower in group II than in controls (51.7 [23.3-82.2] versus 60.5 [32.4-85.9] pmol/l; p < 0.05 by KRUSKAL-WALLIS). Age did not influence the L-arginine plasma levels (p = 0.30). cGMP levels depended on age (p<0.01) and mean pulmonary artery pressure (p <0.01) but not on high pulmonary blood flow (p=0.85; ANOVA). Plasma nitrite and nitrate were not different in both groups and when compared with controls (nitrite: 26.0 [23.5-31.0] micromol/l; nitrate: 26.8 [24.0-32.0] micromol/l).

CONCLUSIONS

Age and pulmonary artery pressure exert important effects on plasma cGMP. Measurement of nitrite and nitrate in plasma alone may not reflect the endogenous NO production. Future studies should evaluate the role of plasma levels of L-arginine in patients with high pulmonary blood flow undergoing repair of their defect.

[Adult patients after surgery of ostium primum type of atrial septal defects in childhood: echocardiography study]

The authors examined, using transthoracic and transoesophageal echocardiography, 36 adult patients (15 men) aged 22 +/- 3.1 years (18-29 years) who were operated 12.2 +/- 3.7 years previously on account of a defect of the atrial septum type ostium primum. In these patients no other congenital cardiac defect was present. In addition to closure of the defect in the patients complete suture of the "cleft" of the anterior cusp of the mitral valve was performed, in 7 partial suture of the "cleft" of the anterior cusp of the mitral valve and in 4 commissuroplasty. In one instance later reoperation with replacement of the mitral valve by a mechanical prosthesis was performed. The control group was formed by 16 healthy volunteers (5 men) aged 22.1 +/- 3 years (19-31 years). Patients operated in childhood on account of an atrial defect of the ostium primum type have on echocardiographic examination, as compared with healthy volunteers, larger atria and the left ventricle, a thicker interventricular septum and left ventricular wall and a higher velocity of left ventricular filling during the late diastole. Higher values of parameters of the size and volume of the left ventricle are associated with the presence of mitral regurgitation. More marked changes of systolic or diastolic left ventricular function are not present, there are not even any echocardiographic signs of higher pressure in the atria and pulmonary artery. In none of the patients a residual shunt at the level of the atrial septum is present. Mitral regurgitation is found in two thirds of the patients, only in one case it was however moderately severe (grade 3). From the results it does not ensue which type of surgery of the "cleft" of the mitral valve has the best long-term results. In none of the patients tricuspid regurgitation of a higher grade than grade 1 is present.

Left-to-right shunt lesions

A left-to-right shunt lesions exists when blood from the left atrium, left ventricle, or aorta transits to the right atrium or its tributaries, the right ventricle, or the pulmonary artery. This article discusses: the incidence, types, embryology, clinical presentations, physical examinations, electrocardiographic features, chest radiographs, echocardiographic and cardiac catheterization issues, treatment, natural history of atrial septal defects, and outcomes of treatment of atrial septal defects, ventricular septal defects, patent ductus arteriosus, and endocardial cushion defects.

[Anesthesia in a patient with along-standing congenital heart malformation of the complete atrioventricular canal type for non-cardiac surgery]

Atrioventricular canal defects are a class of malformation attributable to anomalies in embryonic development of the anterior and posterior endocardial cushions. In the absence of surgical correction, death usually ensues in the first few years of life. Defects as severe as those observed in our patient are rare in adults. We describe the anesthetic management (epidural anesthesia with spontaneous ventilation by laryngeal mask) for a 46-year-old woman with this malformation who underwent emergency laparotomy.

Use of remifentanil in infants

We describe the use of remifentanil in three infants with complex medical issues (hepatic failure, cyanotic heart disease and renal compromise). The short duration of opioid effect even after a long period of drug infusion (18 h) suggests this drug may be useful in some infants. Continued study is warranted.

[Two cases of complete atrioventricular canal defect whose pulmonary vascular resistance were over 10 wood unit.m2 before 6 months of age]

We report two cases with complete form of atrioventricular canal defect (CAVCD) accompanied by Down's syndrome whose pulmonary vascular resistance (Rp) were more than 10 Wood unit.m2 at the age of less than 6 months. One child was 3-month-old boy whose Rp was 12 Wood unit.m2. The open lung biopsy at 3 months old showed histopathological change of Heath-Edwards grade I. He underwent intracardiac repair at the age of 4 months. He is doing well at 30 months of postoperative period. Another child was 5-month-old girl whose Rp was 15.5 Wood unit.m2. Histopathological change of lung at 5 months old demonstrated Heath-Edwards grade III. She underwent intracardiac repair at the age of 7 months, 2 months after lung biopsy. However, she died of oversystemic pulmonary hypertension and low output syndrome 7 days after surgery. The postmortem examination revealed that pulmonary vascular obstructive disease progressed during 2 months interval between the lung biopsy and the operation. In conclusion, cardiac catheterization with estimation of Rp should be performed in the cases of CAVCD, especially in those with Down's syndrome, in early infancy. If Rp is more than 10 Wood unit.m2 and lung biopsy indicates the surgical indication, surgical intervention should be done as soon as possible since the pulmonary vascular obstructive disease may progress in a short period.

Cardiac outflow tract septation process in the mouse model of transposition of the great arteries

It has been reported that all-trans retinoic acid induces transposition of the great arteries (TGA) at 80-90% in ICR mice. The authors revealed that retinoic acid affects the initial formation of the conus cushions leading to a loss of spirality in the cardiac outflow tract. However, the aberrant process of septation has not been precisely defined. In this study, we observed the hearts of live embryos using a video system followed by scanning electron microscopic examination. First, we found that, in the retinoic acid-treated embryos, the proximal outflow tract cushions, in addition to hypoplasia and dysplasia, did not establish the continuity with the distal outflow tract cushions and could not contribute to the outflow septation. Second, the distal outflow tract did not rotate counter-clockwise, retaining the outflow septum anlage in the superoinferior position. Third, a tongue-like mesenchymal tissue had developed on the right anterior rim of the muscular interventricular septum and was incorporated into the interventricular septum. Altogether, these processes contributed to establishing a reversed relationship between the outflow septum anlage and the ventricular septum anlage. On the other hand, right-ward deviation of one or both of the distal outflow tract cushions, relative to the mesenchymal tissue, gave rise to variable degrees of overriding of the pulmonary artery orifice. We conclude that, due to hypoplasia and dysplasia of the proximal outflow tract cushions and lack of distal outflow tract rotation, the outflow septum anlage took an inverted relationship with the ventricular septum anlage. Various types of rightward shift of the outflow tract cushions produced a morphological spectrum of TGA-type cono-truncal anomalies.

Primum atrial septal defect

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.

Twenty-year experience with repair of complete atrioventricular septal defects

BACKGROUND

To determine factors predicting mortality and morbidity after repair of complete atrioventricular septal defect, we retrospectively analyzed preoperative, operative, and postrepair factors on the outcome of 115 consecutive complete atrioventricular septal defect repairs at The Children's Hospital of Wisconsin between January 1974 and December 1993.

METHODS

For the entire experience the operative mortality was 13.9% (16 patients). During the most recent era, January 1988 to December 1993, operative mortality was 3.6% (2 of 55 patients). This was significantly improved from the two previous eras, January 1974 to December 1980, 28% (7 of 25) and January 1981 to December 1987, 20% (7 of 35 patients) (p = 0.02). There were seven late deaths; 10-year actuarial survival, including operative mortality was 81%. Age at complete repair decreased; before 1982 all patients were more than 12 months of age, whereas after 1982 64% (56 of 88 patients) were 12 months of age or less.

RESULTS

Moderate or severe preoperative left atrioventricular valve regurgitation was not a risk factor for operative mortality. For operative survivors with moderate to severe preoperative left atrioventricular valve regurgitation (n = 17), late postoperative left atrioventricular valve regurgitation (follow-up data available on 15 patients) was significantly reduced (severe = 1, moderate = 5, mild = 9; p = 0.007).

CONCLUSIONS

Early mortality was predicted by the era of surgical repair. Conversion to routine repair during infancy was achieved with a simultaneous decrease in operative mortality. For patients with moderate to severe preoperative left atrioventricular valve regurgitation, significant improvement in the degree of left atrioventricular valve regurgitation can be expected without an increase in operative or late mortality or morbidity.

Surgical management of complete atrioventricular canal associated with tetralogy of Fallot

Between 1984 and 1993, 12 children with an atrioventricular canal and tetralogy of Fallot underwent surgical repair. The mean(s.d.) age at operation was 58(18) months, and the mean(s.d.) body weight 15(4) kg. Nine patients underwent 11 palliative procedures. The ventricular septal defect was closed through a combined (right atrial and right ventricular) approach in nine cases, and through a right atrial approach in three, using a prosthetic patch with a wide anterior extension, secured with a running suture. The 'ostium primum' defect was closed with a separate prosthetic patch in 11 cases (double-patch technique). Right ventricular outflow obstruction was relieved by a composite infundibular patch (seven cases) or a transanular patch (five). There were four hospital deaths (33%). These were caused by low cardiac output in three cases and infection in one (three deaths occurred in patients with a transanular patch). One patient has so far died during follow-up. Assessment at 50(36) months by echo-Doppler showed moderate-to-severe 'mitral' regurgitation in three cases, and moderate 'tricuspid' regurgitation with right ventricular dysfunction in one case. Two patients have required further surgery.

Complete atrioventricular septal defect and Ebstein anomaly

The newborn reported here presented with congestive heart failure and cyanosis on the first day of life. Echocardiographic examination revealed complete atrioventricular septal defect and Ebstein anomaly, a rare combination that has not been previously reported in the literature.

[Surgical treatment of incomplete endocardial cushion defect in adult patients]

Seven adult patients (> or = 40 years old) and six pediatric patients with incomplete endocardial cushion defect (ECD) underwent corrective surgery in our institution. Preoperative catheterization study showed that the left-to-right shunting rate and the pulmonary-to-systemic flow ratio were greater in adult patients than those in pediatric patients, but systolic pulmonary arterial pressure was not high and similar in the two groups. The degree of mitral regurgitation by left ventriculography was mild or moderate in both groups. However, in adult patients, a variety of arrhythmias were observed. Postoperatively, NYHA grades and arrhythmia improved markedly in the adult patients. Surgical correction for ECD is recommended even in adult patients before aggravation of cardiac failure and arrhythmia.

Long-term follow-up of cardiac rhythms after biatrial transseptal approach (Dubost's incision)

Biatrial transseptal approach (Dubost's incision) was performed 54 times on 47 patients from November 1973 to December 1982 at National Fukuoka Higashi Hospital in Japan. The patients consisted of 19 males and 28 females, with ages ranging from 14 to 66 (mean 45.9 years). Forty-four out of 47 cases had rheumatic heart disease while one had endocardial cushion defect, one had Lutembacher's syndrome, and one had left atrial myxoma. Preoperative electrocardiograph showed atrial fibrillation in 37 cases (78.7%) and normal sinus rhythm in 10 cases (21.3%). The follow-ups of the patients were a minimum of 8 years and a maximum of 16 years (mean 9.6 years) with 97.8% completion. Cumulative follow-up period was 448.9 patient years. Postoperatively, atrial fibrillation persisted in all except two. In those patients, normal sinus rhythm was observed until postoperative six months and seven years, respectively. Normal sinus rhythm persisted in six cases, and changed into junctional rhythm in four. One of them changed into atrial fibrillation at 10.6 years postoperatively. We conclude that Dubost's incision provides an excellent operative field for mitral and tricuspid valve surgery without serious internodal conduction disturbances.

The effects of right ventricular hemodynamics on left ventricular configuration

While abnormalities of right ventricular hemodynamics are known to affect interventricular septal position and shape, their effect on left ventricular shape and possibly function have been less well studied. Accordingly, the two-dimensional echocardiographic appearance of the left ventricle was studied in 11 patients with right ventricular volume overload, 16 with right ventricular pressure overload, nine with combined pressure and volume loads of the right heart and 17 normal control subjects. An index of left ventricular shape (SI) was calculated from end diastolic, mid systolic and end systolic left ventricular short axis area (A) and circumference (C) taken at the level of the tips of the mitral leaflets, using the formula SI = 4 pi A/C2. The left ventricles of normal subjects had relatively round configurations throughout the entire cardiac cycle (SI = 0.86 at end diastole, mid and end systole). Pure right ventricular volume overload produced left ventricular deformity at end diastole only (SI at end diastole = 0.78), with a return to normal configuration during systole. Pure right ventricular pressure load resulted in left ventricular deformation throughout the cardiac cycle, with shape indices ranging between 0.77 and 0.80. Combined pressure and volume overload produced left ventricular deformation during the entire cycle which was of an order of magnitude more severe than any other group (SI = 0.69, 0.70 and 0.65, at end diastole, mid and end systole, respectively). The shape index at end systole showed an inverse correlation with the relative right-to-left ventricular systolic pressure ratio (P = 0.001, r = 0.76). It is concluded that left ventricular configuration is affected by right ventricular hemodynamics.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical and medical results of complete atrioventricular canal: a ten year review

The files of 121 patients who presented to Children's Hospital of Michigan over the last 10 years with complete atrioventricular (AV) canal were reviewed to evaluate long-term management and overall outcome. Of 121 patients, 70 underwent corrective surgery, 21 (30%) of whom died perioperatively. The surgical mortality rate was 13% when patients with hypoplastic left or right ventricle (n = 6), double-orifice mitral valve or extreme deficiency of mitral tissue (n = 5), and pulmonary vascular obstructive disease (n = 5) were excluded. Of the 49 patients who survived operation, 36 are in New York Heart Association class I, 1 patient requires a pacemaker and 3 died late. In 34 of the 51 patients (28%) who did not undergo operation, pulmonary vascular obstructive disease developed; it occurred within 12 months in 10 patients (8%). Eight other patients who did not undergo operation died before planned surgery (age 1 to 9 months). Although surgical prognosis in good candidates is acceptable, the overall prognosis for children with complete AV canal is guarded because of the risk of early death or early pulmonary vascular obstructive disease and frequently unfavorable anatomy.

Results of total correction in complete atrioventricular septal defects with congenital or surgically induced right ventricular outflow tract obstruction

The outcome of total repair in 29 children who had complete atrioventricular septal defect (AVSD) and congenital or surgically induced right ventricular outflow tract obstruction (RVOTO) is reviewed. All 11 patients with congenital RVOTO had normal pulmonary artery (PA) pressure before the complete repair. Of the 18 children who had undergone PA banding, seven had PA pressure above 30 mm Hg (mean, 53.5). Two had elevated pulmonary vascular resistance (greater than 3 units). Early mortality was 18.2% for the patients with congenital RVOTO and 44.4% for those who had undergone PA banding (p not significant). After a mean follow-up of 5 years, the results are good in the survivors of both groups. Analysis of multiple-risk factors indicate that, for the total group of patients, death was significantly more common in children less than 5 years of age (p less than 0.01) or less than 15 kg (p less than 0.02) than in older or larger patients.

Secondary left atrioventricular valve replacement in atrioventricular septal (AV canal) defect: a method to avoid left ventricular outflow tract obstruction

Patients with atrioventricular septal defects are morphologically predisposed to subaortic obstruction. Some individuals require secondary left atrioventricular valve replacement for severe incompetence persisting after repair, and they are especially susceptible to left ventricular outflow tract obstruction. A surgical technique is described for replacement of the atrioventricular valve which seems to avoid the complication of left ventricular outflow tract obstruction by the prosthesis.

Cardiovascular disease in Down syndrome

This article focuses on the clinical evaluation of children with cardiovascular diseases associated with Down syndrome. Recent advances in diagnosis and management are discussed and the medical or surgical approach to the patient with severe cardiovascular malformations is presented.

Postoperative changes of pulmonary vascular resistance in patients with complete atrioventricular canal defect. Relation to the age at primary repair

The postoperative changes of pulmonary vascular resistance (PVR) of two age groups of children with complete atrioventricular canal (CAVC) were compared. Patients were divided by age at the time of primary repair; Group-1 (G-1, n = 4) with age below 2 years (average 13.8 mo.) and Group-2 (G-2, n = 5) with age over 2 years (average 44.0 mo.). All except one were Down's syndrome. Preoperatively, pulmonary to systemic resistance ratio (Rp/Rs) were 0.87 +/- 0.50 in G-1 and 0.41 +/- 0.13 in G-2 (n.s.), and postoperative study (average 6.5 mo.) showed no significant falls in Rp/Rs in both groups. However, G-2 showed significantly lower Rp/Rs postoperatively (0.79 +/- 0.19 in G-1 vs 0.27 +/- 0.12 in G-2, p less than 0.05). Mean pulmonary artery pressure (mPA) showed significant fall after surgery in only G-2 (66.8 +/- 6.6 to 31.8 +/- 11.6 mmHg, p less than 0.005). Anatomically, type-A showed better postoperative change in mPA compared to type-C. This study summarized the early progression of pulmonary vascular obstructive disease with poor postoperative improvement even the primary repair was done before 2 years of age. The less advanced pulmonary vascular disease in G-2 might have some relations to the natural selection of the disease.

Anatomic and functional "obstruction" of the outflow tract in atrioventricular septal defects with separate valve orifices ("ostium primum atrial septal defect"): an echocardiographic study

Left ventricular (LV) outflow tract (OT) obstruction can be treacherous in any form of atrioventricular (AV) septal defect. The properties of the LVOT were investigated echocardiographically in 64 patients with separate valve orifices ("ostium primum atrial septal defect") who had survived corrective surgery. M-mode and cross-sectional echocardiographic (echo) images were made of the LVOT. The degree of malalignment of the aorta with the ventricular septum, the left atrium-aortic ratio, the fractional LV shortening and the diameter of the LVOT were recorded. Fixed anatomical obstruction was found in 3 patients, consisting of muscular bands or abnormal attachment of tension apparatus. Malalignment of the aorta with the ventricular septum was found in 62% of the patients. The diameter of the LVOT was smaller than that of the aortic root in 71% of the cases. The mean diameter of the LVOT was 92 +/- 27% (range 35 to 143%) of the aortic root diameter. Because its walls are mainly muscular, the LVOT constricts during systole. The mean end-systolic diameter of the LVOT was 77 +/- 22% (range 23 to 129%) of the aortic root diameter. Sequential measurements showed that the LVOT constricted gradually, but the velocity of constriction in patients with the most severe narrowing showed a distinct maximum in the first fifth of systole. In conclusion, a series of elements contribute to a potentially perilous arrangement of the LVOT in patients with AV septal defect. This intrinsically narrow tunnel was constricted during systole by its muscular walls.(ABSTRACT TRUNCATED AT 250 WORDS)

[Electro-vectorcardiographic behavior of right bundle branch block in endocardial cushion defects. Its probable relation to the so-called left anterior fascicular hemiblock]

We have investigated the possible ECG signs of incomplete Left Anterior Hemiblock (LAH). As an experimental model we chose the endocardial cushion defect, which is proved to have a ventricular activation correspondent to different degrees of LAH due to the particular disposition of the AV node and the His bundle. The VCG of 50 patients with endocardial cushion defect were divided into 5 groups according to the entity of the left and superior deviation of the maximum left vector. Comparison with the ECG signs shows that: a) minimal degrees of LAH occur with simple counterclockwise rotation of the frontal loop without a significant left axis deviation; b) there is no linear correlation between the importance of the left axis deviation and the signs of left ventricular activation asincronism. We conclude that, with the exception of this particular congenital heart disease, minimal LAH degrees can only be suspected on the basis of a counterclockwise VCG frontal loop, because the ECG diagnosis is possible only when the left axis deviation becomes important.

Effect of palliative and corrective surgery on ventricular volumes in complete atrioventricular canal

The effect of pulmonary artery banding (PAB) and intracardiac repair on ventricular volumes was studied in 35 patients with uncomplicated complete atrioventricular canal (CAVC). Right ventricular (RV) and left ventricular (LV) end-diastolic volumes (EDV), determined from biplane cineangiograms using Simpson's rule, were expressed as a percent of normal mean (% Nl) for body surface area; normal range (mean +/- 1SD) is equivalent to 75%-125% Nl. In preoperative studies (RV 26, LV 33), EDV averaged 149 +/- 51% and 184 +/- 50% Nl, respectively, P vs Nl less than 0.001 for both. In one of 26 patients, RV was very small (45% Nl), and one of 33 had a small LV (70% NI). In 13 patients studied post-PAB, RVEDV and LVEDV were lower than in the preoperative group (P less than 0.001) and averaged 114 +/- 40% and 126 +/- 52% Nl, respectively. In three of 13, RV was small (67% and 71% Nl) or very small (56% Nl). Three others had a small (71% and 67% Nl) or very small (56% Nl) LV. In serial pre- and post-PAB studies (RV 9, LV 11), EDV was increased or normal in all preoperatively. In seven of nine, RVEDV decreased, falling below normal range in three. In eight of 11, LVEDV decreased, falling below normal in three. Following repair, RV and LVEDV averaged 80 +/- 20% Nl and 126 +/- 23% Nl, respectively, in seven patients. Four of the seven had RVEDV below normal range. Two patients with a small ventricle had intracardiac repair and did well.(ABSTRACT TRUNCATED AT 250 WORDS)

Complete atrioventricular canal with survival to the eighth decade

Survival to the eighth decade of patients with atrioventricular canal is extremely rare. A patient is presented with such survival of the complete form of the defect. This possibly represents the first such report in the medical literature. The value of 2-dimensional echocardiography, particularly with venous contrast studies, in establishing the diagnosis, is shown.

Efficacy of pulmonary artery banding in infants with complete atrioventricular canal

Total correction in infants less than 1 year old with complete atrioventricular (AV) canal carries a significant operative mortality. However, past reports suggest that the alternative palliative procedure, pulmonary artery banding (PAB), may be contraindicated in the presence of severe mitral insufficiency and/or a large left ventricular to right atrial shunt. Contrary to these previous reports, we report the results in 21 consecutive patients with congestive heart failure who underwent PAB at a mean age of 3.9 +/- 2.8 months and at a weight of 3.6 +/- 0.9 kg. (17/21 less than 6 months). Regardless of mitral valve competency, PAB was performed in conjunction with ligation of a patent ductus arteriosus (11 patients) and coarctation repair (two patients) with one death secondary to gastrointestinal bleeding (4.7% in-hospital mortality); one patient required early band readjustment because of hypoxemia. Repeat cardiac catheterization in 10 patients performed 4 to 41 months after PAB showed significant reduction in pulmonary hypertension and flow with no change in pulmonary vascular resistance. All infants were symptomatically improved after PAB and four have undergone successful total correction. Previous reports since 1977 indicate a significantly higher risk for total repair of complete A V canal before 1 year of age (36/147, 24%) than the risk for PAB in this series (p less than .05). Therefore, we believe that PAB is a rational alternative to total repair as the initial surgical treatment for symptomatic infants with complete A V canal, particularly when anatomic variants known to increase operative risk are recognized before cardiotomy.

Epicardial and endocardial activation in patients with endocardial cushion defect

Epicardial and left ventricular endocardial activation were assessed in 5 patients (aged 4 months to 9.5 years) with endocardial cushion defect (ECD) during surgical repair. Epicardial activation was recorded from 40 to 47 sites over the epicardium; left ventricular endocardial activation was measured at 3 sites immediately after institution of cardiopulmonary bypass. Compared with the reported activation sequence in normal hearts, the pattern of excitation in hearts of patients with ECD was abnormal; epicardial excitation began at the left ventricular diaphragmatic surface and spread laterally and anteriorly over the anterobasal left ventricle. It then merged with right ventricular wavefronts ending along the right ventricular anterior atrioventricular groove and outflow tract. Left ventricular endocardial activation also occurred earliest in the diaphragmatic segment of the left ventricle with later wavefronts recorded laterally and anteriorly. This study demonstrates, for the first time in human subjects, correlation between left ventricular epicardial and endocardial activation in patients with ECD. The data indicate that earliest endocardial and epicardial activation occurs at the left ventricular diaphragmatic segments of the heart, and are consistent with the known posterior and inferior displacement of the specialized atrioventricular conduction system in patients with ECD.