Roger B.B. Mee

Task Force 4: organization of delivery systems for adults with congenital heart disease

The delivery of appropriate care to adults with congenital heart disease (ACHD) is a largely unmet challenge in the U.S. and elsewhere. To meet this challenge, a structure and process for the organization and delivery of care is proposed. We will use the “severe heart failure care model”

Evidence for rejection of homograft cardiac valves in infants

OBJECTIVEnConcern about the durability of small homograft cardiac valves has been expressed by surgeons, and evidence has been found that homograft valves evoke a recipient immune response. We reviewed our experience with homograft valves for evidence of rejection.nnnMETHODSnA search of our files revealed 11 homograft cardiac valves removed at reoperation and one at autopsy. Six valves were from adults, five were from infants, and one was from a 13-year-old child. Immunohistochemical studies with antibodies against smooth muscle actin, CD20, CD43, CD34, and CD68 were performed on the homografts containing inflammatory infiltrates. These valves happened to be the valves from the five infants. These five valves were also stained with Gram and Gomoris methenamine silver stains.nnnRESULTSnThe failed homografts from the adults and 13-year-old child showed leaflet calcification, fibrosis, and degeneration, but no inflammation. The valves from the infants all failed in less than 8 months. The valve leaflets were thickened, and the valve leaflets and aortic sleeves contained a hyperplastic intimal layer with numerous spindle cells positive for smooth muscle actin embedded in a glycosaminoglycan matrix. The homografts contained multiple foci of inflammation consisting of T lymphocytes (in all five infant valves) and B lymphocytes (in three of the five infant valves). Special stains for organisms were negative.nnnCONCLUSIONSnRapid failure plus lymphocytic infiltration in valve leaflets and aortic sleeves is consistent with rejection. The hyperplastic intima is similar to coronary arteries in transplant-associated vascular disease. Our observations are consistent with other reports of rapid failure of homograft valves in this age group.

Modified Norwood procedure for hypoplastic left heart syndrome

BACKGROUNDnSince June 1994, we have used a modification of the Norwood technique in 13 patients presenting with the hypoplastic left heart syndrome or similar variants.nnnMETHODSnThis technique involves coarctation repair, arch reconstruction, and creation of a neo-ascending aorta using autologous great vessel tissue only. Pulmonary blood flow is provided by a central shunt of 3.0- to 4.0-mm Gore-Tex.nnnRESULTSnThe mean age and weight at operation were 15 days (range, 1 to 77 days) and 3.2 kg (range, 1.7 to 4.6 kg), respectively. The mean circulatory arrest time was 32 minutes (range, 25 to 50 minutes). There was one operative death, and there have been no late deaths. Seven patients have gone on to conversion to a bidirectional cavopulmonary shunt at a mean age of 6 months. There have been no cases of recurrent coarctation, arch obstruction, or left pulmonary artery stenosis. Significant coronary insufficiency requiring revision of the ascending aortic reconstruction has developed in 2 patients.nnnCONCLUSIONSnWe believe this approach offers the advantage of using the patients own native tissue for all great vessel reconstruction. This technique may also allow 10 to 15 minutes less of circulatory arrest time. The theoretic benefits include improved growth of repaired structures and avoidance of homograft or prosthetic material. The long-term results remain to be elucidated.

Repair of insufficient bicuspid aortic valves

A technique for the repair of bicuspid aortic valves that includes resection of the flail segment of the prolapsing leaflet, annuloplasty, and resection of the raphe, when present, has been reported. To assess the efficacy of this technique in the repair of insufficient bicuspid aortic valves, the results in 72 consecutive patients were assessed. The mean age of the patients was 39 +/- 11 years; 94% were male. Fifty-six patients (78%) underwent isolated aortic valve repair, 9 (12.5%) underwent aortic and mitral valve repair, and 7 (9.7%) had other associated procedures. All patients underwent leaflet resection, including 35 (48%) at the raphe. The mean aortic occlusion time was 39 +/- 12 minutes. There were no operative deaths. The severity of aortic insufficiency, as assessed by Doppler echocardiography (graded from 0 to 4) preoperatively and intraoperatively and at late follow-up, was 3.6 +/- 0.6, 0.4 +/- 0.4, and 0.9 +/- 0.8, respectively, with a p value of < 0.0001 for the latter two values versus the preoperative one. There have been no postoperative deaths. Patients did not receive anticoagulation treatment and there were no strokes or episodes of endocarditis. Six patients have required reoperation; 3 underwent repeat repair. The Kaplan-Meier freedom from aortic valve reoperation probabilities at 12 and 24 months were 94% and 89.5%, respectively. We conclude that valvuloplasty for insufficient bicuspid aortic valves is technically safe, is associated with a low incidence of recurrent insufficiency, and has been associated with no other valve-related complications.

Factors associated with early extubation after cardiac surgery in young children.

Objective Children undergoing congenital heart surgery require mechanical ventilation. We sought to identify pre- and intraoperative factors (PrO, IO) associated with successful early extubation <24 hrs. Design and Patients We performed a retrospective chart review of children <36 months old who underwent congenital heart surgery from January 1998 to July 1999. Setting Pediatric intensive care unit in a children’s hospital. Measurements Generalized Estimating Equation models were fit to assess the association between PrO and IO and early extubation while accounting for the correlation between surgeries performed on the same patient. Estimated odds ratios (EOR) and 95% confidence intervals were calculated. Multivariable models were constructed using a forward selection process with inclusion criteria of p < .05. Multivariable models, which included PrO and IO variables, were adjusted for procedure group. The area under the receiver operating characteristic curve was computed for each model. Results A total of 203 children underwent 219 surgeries; 103 (47%) children were extubated in <24 hrs, with only one (1%) failed extubation. PrO variables associated with successful early extubation included age >6 months (EOR, 6.1), absence of pulmonary hypertension (EOR, 9.1), gestational age >36 wks (EOR, 4.6), and absence of congestive heart failure (EOR, 2.4). IO variables were less likely to be associated with successful early extubation. Our model of PrO variables with multiple factors showed that presence of two factors was associated with an EOR of 4.2 for successful early extubation compared with children with zero or one factor. Presence of three and four factors was associated with an EOR of 18.0 and 76.5, respectively. The area under the receiver operating characteristic curve for this model is 0.816. Incision type, complex vs. simple procedure, and palliative vs. complete repair were not associated with success of early extubation. Conclusions Early extubation is possible in many very young children undergoing congenital heart surgery, with a low rate of failed extubation. The model would be improved by prospective validation with larger numbers at multiple institutions.

Senning plus arterial switch operation for discordant (congenitally corrected) transposition

BACKGROUNDnCongenitally corrected transposition of the great arteries is a complex cardiac lesion, usually associated with ventricular septal defect, left ventricular outflow tract obstruction, and tricuspid valve abnormalities. A subset of patients without left ventricular outflow tract obstruction have undergone Senning plus arterial switch operation in an attempt to place the left ventricle in the systemic circuit and the right ventricle in the pulmonary circuit.nnnMETHODSnFourteen patients have had the operation performed since July 1989. Age and weight medians were 12 months (range, 0.5 to 120 months) and 8.2 kg (range, 3.2 to 34 kg). All but 1 patient had a left ventricular to right ventricular pressure ratio greater than 0.7, due to a large ventricular septal defect (with or without a previous pulmonary artery band), severe congestive heart failure caused by right ventricular dysfunction and tricuspid insufficiency, or a pulmonary artery band for left ventricular retraining. At least 10 patients had strong contraindications to classic repair, including right ventricular hypoplasia (n = 2), moderate to severe right ventricular dysfunction (n = 5), or moderate to severe tricuspid insufficiency (n = 9).nnnRESULTSnThere was one hospital death, occurring in a neonate (7%; 95% confidence interval = 0% to 34%). Actuarial survival beyond 10 months is 81% (95% confidence interval = 42% to 95%), currently with 389 patient-months of total follow-up time. The median grade of tricuspid insufficiency fell from 3/4 preoperatively to 1/4 postoperatively (p = 0.003). Right ventricular function is normal in 11/12 current survivors, all but 1 of whom are in New York Heart Association class I or II.nnnCONCLUSIONSnSenning plus arterial switch operation is a good option for selected patients with congenitally corrected transposition of the great arteries with a similar or lower early risk (as compared with classic repairs). Some of the long-term problems associated with congenitally corrected transposition of the great arteries may be avoided with this strategy.

Staged repair of tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries

OBJECTIVEnTo assess the results of a staged surgical approach for tetralogy of Fallot with pulmonary atresia, hypoplastic or absent pulmonary arteries, and major aortopulmonary collateral arteries.nnnMETHODSnWe retrospectively reviewed a consecutive series of these patients from a single institution.nnnRESULTSnFrom July 1993 to April 2001, 46 consecutive patients with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collateral arteries were treated with staged surgical repair. The operative sequence usually began with a central aortopulmonary shunt followed by unifocalization of aortopulmonary collateral arteries depending on the source and distribution of pulmonary blood flow. Twenty-eight patients (61%) subsequently underwent complete repair with ventricular septal defect closure and right ventricle to pulmonary artery connection. Those patients who underwent complete repair had a median of 3 total operations (range 1-6). The ratio of the mean pulmonary artery pressure to the mean systemic blood pressure at the time of complete repair was 0.36 (range 0.19-0.58). Two of the 28 repaired patients (7.1%) required subsequent fenestration of the ventricular septal defect closure due to later development of supersystemic right ventricular pressure and right ventricular failure. Eighteen patients (39%) have undergone 1 or more staging operations and are considered good candidates for eventual complete repair. There were no hospital deaths. There was 1 late death (2.2%; 95% CI 0.4-11.3%) in a patient born prematurely who developed severe bronchopulmonary dysplasia precluding complete repair.nnnCONCLUSIONSnFor tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries, a staged surgical approach yields low overall mortality and acceptable hemodynamics after complete repair.

Results of the double switch operation in the current era

BACKGROUNDnIn patients with atrioventricular and arterioventricular discordance congenitally corrected transposition, the morphologically right ventricle may progressively deteriorate while functioning in the systemic circuit. The double switch operation has been proposed to limit this functional deterioration.nnnMETHODSnFrom October 1993 to August 1998, the records of 27 patients with congenitally corrected transposition were reviewed. Age at operation ranged from 3 months to 55 years. Associated defects included ventricular septal defects in 18, pulmonary atresia in 7, and pulmonary stenosis in 11 patients. Twenty-two patients had double switch operations (10 arterial switch plus Senning procedures and 12 Rastelli plus Senning procedures). Five patients were not candidates for the double switch. Before the double switch, 6 patients required pulmonary artery banding and 10 had functioning systemic to pulmonary artery or cavopulmonary shunts.nnnRESULTSnThere was no early or late mortality. Two patients required pacemaker implantation, both later regained normal sinus rhythm. Tricuspid valve function improved in all patients except one. Moderate left ventricular dysfunction developed 5 months postoperatively in 1 patient.nnnCONCLUSIONSnThe double switch operation can be performed in selected patients with minimal early morbidity and mortality. Longer follow-up is necessary to determine whether this complex approach is indeed warranted.

Improving early and intermediate results of truncus arteriosus repair: a new technique of truncal valve repair

BACKGROUNDnDespite improved surgical results for truncus arteriosus, overall mortality rates, remain higher than those reported for other complex congenital heart diseases, especially with truncal valve regurgitation or an interrupted aortic arch.nnnMETHODSnSeventeen patients had complete repair of the truncus arteriosus at the Cleveland Clinic Foundation between August 1993 and June 1997. The age at operation ranged from 2 days to 4.5 years. Associated abnormalities included interrupted aortic arch in 3 patients and abnormal coronary artery anatomy in 3. Four patients had more than moderate truncal valve insufficiency requiring concomitant truncal valve repair.nnnRESULTSnThere were no early deaths and only one late death at a mean follow-up of 24 months. The death occurred 3 months postoperatively and resulted from refractory pulmonary vascular obstructive disease in a patient who was referred at 1 year of age. Reoperation was required in 4 patients.nnnCONCLUSIONSnEven in the presence of associated anomalies complete repair was performed with a low mortality rate. Truncal valve repair can be performed safely in the neonate with good results.

Ventriculo-arterial discordance: switching the morphologically left ventricle into the systemic circulation after 3 months of age

OBJECTIVEnTo retrospectively examine a 4 year policy of restoring the morphologically left ventricle to the systemic circuit in patients presenting after 3 months of age with ventriculo-arterial discordance with or without associated atrio-ventricular discordance. This policy was stimulated by the known tendency of the morphologically right ventricle to develop dysfunction sooner or later when left in the systemic circuit. Such a policy dictates a more complex surgical approach and, at this point, it remains controversial whether or not the increased surgical complexity is warranted.nnnMETHODSnFrom July 1, 1993 to March 31, 1997, a total of 29 patients were entered into a protocol for placement of the morphologically left ventricle into the systemic circuit. Three groups of patients were identified. Group I; congenitally corrected transposition in 14 patients -- were treated with either a Senning plus arterial switch operation or Senning plus Rastelli procedure. Group II; failed atrial switch procedure in 12 patients of which nine proceeded to arterial switch operation with Senning or Mustard takedown and atrial reseptation. Group III; D-transposition of the great vessels presenting more than 1 year after birth in three patients who underwent arterial switch operation alone. A deconditioned morphologically left ventricle required reconditioning by means of preparatory pulmonary artery banding in 17 of 29 patients. In the patients requiring pulmonary artery banding, an average of 2.1 pulmonary artery bandings was required to prepare the morphologically left ventricle for a systemic pressure workload.nnnRESULTSnIn those patients with a deconditioned morphologically left ventricle requiring preparatory pulmonary artery banding, the mean ratio between the left ventricular and right ventricular systolic pressure increased from 0.48 to 0.95. The left ventricular mass increased from 46.6 to 81.8 g/m2 in five patients subjected to serial MRI measurement. Three patients failed the preparatory pulmonary artery banding and did not proceed to anatomical correction. Two subsequently died at a later time. In the patients proceeding to complete anatomical correction: group I -- there were no early or late deaths. Two patients required pacemaker implantation post-operatively. Group II -- there were two in-hospital deaths, one early due to intrapulmonary hemorrhage and one late, secondary to postoperative left ventricular failure with a stormy post-operative course requiring successful ECMO placement and weaning. These patients were 18 and 25 years old, respectively. One patient proceeded to cardiac transplantation 3 months after surgery due to ongoing morphologically left and right ventricular dysfunction. Group III -- all patients continue to do well.nnnCONCLUSIONSnLate anatomic correction of ventriculo-arterial discordance with or without atrio-ventricular discordance can be performed at a relatively low risk. Reconditioning of the morphologically left ventricle can be achieved by sequential pulmonary banding but is not without risk. Failure to achieve adequate reconditioning of the morphologically left ventricle by pulmonary artery banding in the older patient probably increases the risk of non-survival and may be offset by timely transplantation. Longer follow-up and an assessment of the functional status of these patients is required to assess whether or not this complex surgical approach is indeed warranted.