Single dose myocardial protection technique utilizing del Nido cardioplegia solution during congenital heart surgery procedures.

BACKGROUND: The single dose cardioplegia technique for myocardial protection during congenital heart surgery is a viable alternative to multidose protocols. METHODS: Thirty-four pediatric patients with aortic cross clamp times greater than 90 minutes were grouped by modified adult (MA) multidose solution or del Nido (dN) single dose solution. Also, data from eight patients where the cross clamp times were greater than two hours on one dose of dN solution were included. RESULTS: In the 90-minute plus arm of the study, there were no significant differences between the groups when comparing the risk adjustment for congenital heart surgery (RACHS) (p=0.6), cardiopulmonary bypass times (CPB) (p=0.5), aortic cross camp times (p=0.5), weights (p=0.7) and number of intraoperative exogenous blood units (p=0.5). There were significant differences between the groups (p<0.05) in the number of cardioplegia doses and with perioperative glucose levels. In the greater than two hours group, the incidence of complete heart block (CHB) was 0.125% and there were no deaths or mechanical circulatory support (MCS) devices used. CONCLUSION: del Nido cardioplegia solution is a reasonable tool for myocardial protection during congenital heart surgery that significantly decreased the number of cardioplegic interventions and perioperative glucose values in our study groups.

Twenty-year experience with heart transplantation for infants and children with restrictive cardiomyopathy: 1986-2006.

Idiopathic restrictive cardiomyopathy (RCM) is a rare cardiomyopathy in children notable for severe diastolic dysfunction and progressive elevation of pulmonary vascular resistance (PVR). Traditionally, those with pulmonary vascular resistance indices (PVRI) >6 W.U. x m(2) have been precluded from heart transplantation (HTX). The clinical course of all patients transplanted for RCM between 1986 and 2006 were reviewed. Preoperative, intraoperative and postoperative variables were evaluated. A total of 23 patients underwent HTX for RCM, with a mean age of 8.8 +/- 5.6 years and a mean time from listing to HTX of 43 +/- 60 days. Preoperative and postoperative (114 +/- 40 days) PVRI were 5.9 +/- 4.4 and 2.9 +/- 1.5 W.U. x m(2), respectively. At time of most recent follow-up (mean = 5.7 +/- 4.6 years), the mean PVRI was 2.0 +/- 1.0 W.U. x m(2). Increasing preoperative mean pulmonary artery pressure (PA) pressure (p = 0.04) and PVRI > 6 W.U. x m(2) (chi(2)= 7.4, p < 0.01) were associated with the requirement of ECMO postoperatively. Neither PVRI nor mean PA pressure was associated with posttransplant mortality; 30-day and 1-year actuarial survivals were 96% and 86%, respectively. Five of the seven patients with preoperative PVRI > 6 W.U. x m(2) survived the first postoperative year. We report excellent survival for patients undergoing HTX for RCM despite the high proportion of high-risk patients.

Bidirectional cavopulmonary anastomosis: impact on diastolic ventricular function indices.

Systolic ventricular function has been demonstrated to remain unchanged following bidirectional cavopulmonary anastomosis (BCPA). The effects of BCPA on diastolic ventricular performance have not been critically assessed. The objective of this study was to evaluate the changes in diastolic ventricular function indices early after BCPA. Nineteen patients were enrolled prospectively. Transthoracic echocardiograms were performed at a median of 4 days prior to and 5 days subsequent to BCPA. Diastolic and systolic echocardiographic indices of ventricular performance were measured for the dominant ventricle. End diastolic volume decreased postoperatively (71.1 +/- 21.1 vs 68.08 +/- 17.9 ml/m2, p = 0.05). Tei index increased postoperatively (0.51 +/- 0.2 vs 0.62 +/- 0.1, p = 0.002), whereas inflow Doppler E velocity (70.3 +/- 13 vs 56.3 +/- 24.7 cm/sec, p = 0.04), E/A ratio (1.18 +/- 0.52 vs 0.84 +/- 0.2, p = 0.02), tissue Doppler E' velocity (9.5 +/- 2.5 vs 6.4 +/- 3.2 cm/sec, p = 0.03) and diastolic flow propagation velocity (56.5 +/- 12 vs 52.8 +/- 11 cm/sec, p = 0.04) all decreased. There was no change in ventricular mass, area change fraction, heart rate, or inflow Doppler A or tissue Doppler A' and S' velocities. This study demonstrated that diastolic indices of ventricular performance are altered indicating decreased diastolic function early following BCPA. Whether this observation is a result of a change in ventricular mass:volume ratio, loading conditions of the ventricle, ventricular geometry, or the effects of cardiopulmonary bypass remains to be determined.

Expression of adenylyl cyclase V/VI mRNA and protein is upregulated in cyanotic infant human myocardium.

We have previously demonstrated that both basal and isoproterenol-stimulated activities of myocardial adenylyl cyclase were greater in cyanotic patients with tetralogy of Fallet (TOF) than those in acyanotic patients. However, it was not determined whether increased enzyme activity was related to a similar increase in adenylyl cyclase protein and mRNA expression. In the current study, we examined the mRNA and protein expression of cardiac adenylyl cyclase, types V and VI, in cyanotic and acyanotic patients with TOF. Ribonuclease protection assays and immunoblotting were performed on myocardial specimens obtained from cyanotic patients with TOF and acyanotic patients with TOF or ventricular septal defect. We demonstrated that in both cyanotic and acyanotic patients, there was more type V adenylyl cyclase mRNA than type VI. Types V and VI cardiac adenylyl cyclase mRNA were significantly increased in myocardium of the cyanotic group compared to the acyanotic group. Protein expression of both V and VI adenylyl cyclases was correspondingly upregulated in cyanotic patients compared to acyanotic patients. Our results indicate that gene and protein expression of cardiac adenylyl cyclases, types V and VI, is increased in the cyanotic myocardium. These results suggest that chronic hypoxemia may regulate the expression of adenylyl cyclase enzymes.

Bulboventricular foramen resection: hemodynamic and electrophysiologic results.

BACKGROUND: The two major surgical approaches to the relief of bulboventricular foramen (BVF) obstruction in patients with single left ventricle (LV) are the Damus-Kaye-Stansel (DKS) procedure or direct BVF resection. Theoretical advantages of the DKS include better out-flow gradient relief, lower potential incidences of postoperative heart block and lower incidences of reoperation. Potential disadvantages of this approach include increased semilunar valvar insufficiency, lack of feasibility when attempting septation-type operations for univentricular hearts, and a technically more difficult operation. We report the results of direct surgical BVF resection. METHODS: From June 1990 to June 1999, 9 patients had direct BVF resection performed at our institution. The median age at surgery was 16.5 years (range 1 month to 27 years). Diagnoses in these patients were [S,L,L] single LV (n = 8) and [S,D,D] single LV tricuspid atresia (n = 1). Eight of 9 patients had pulmonary artery bands placed either before BVF resection or at the same time as this procedure. Three patients required reoperation for reobstruction at the BVF (12 total operations in 9 patients). RESULTS: Median preoperative peak systolic gradient across the BVF measured at cardiac catheterization was 47 mm Hg (range 10 to 63 mm Hg). The median peak gradient measured by Doppler echocardiography was 44 mm Hg (range 5 to 125 mm Hg). Eight of 9 patients survived the operation to discharge from the hospital and 7 of 9 are alive at follow-up. At a median follow-up of 22 months (range 5 to 76 months), 8 of 8 surviving patients had an unobstructed BVF as determined by qualitative two-dimensional echocardiography and Doppler color flow imaging. There was one perioperative and one late death 5 months postoperatively (secondary to fungal sepsis). No patient developed new or worsened aortic insufficiency after BVF resection. Eight of 9 patients had no change in AV nodal conduction after surgery. One patient developed Mobitz II heart block requiring postoperative implantation of a pacemaker. CONCLUSIONS: Direct resection of an obstructive BVF can be performed with total relief of obstruction although reoperation may be required. Atrioventricular nodal function can be preserved in most patients with this operative approach, including those with [S,L,L] segmental anatomy.

Heart transplant in a factor VIII-deficient patient with a high-titre inhibitor: perioperative management using high-dose continuous infusion factor VIII and recombinant factor VIIa.

Four years prior to transplantation, a 14-year-old boy with severe haemophilia A and a high-responding factor VIII (FVIII) inhibitor developed an anteroseptal myocardial infarct while receiving high doses of an activated prothrombin complex concentrate (PCC). Cardiac transplantation was required for survival because of the ensuing cardiomyopathy. At surgery, the patient's inhibitor titre was 1.8 Bethesda units (BU). High-dose bolus therapy, followed by a continuous infusion of FVIII provided excellent operative and initial postoperative haemostasis without additional blood-product support. Once anamnaesis developed on day 6 postoperatively, recombinant factor VIIa (rFVIIa) therapy was initiated. Haemostasis remained excellent, except for the transient increase in chest-tube bleeding that was noted on day 7. epsilon-Aminocaproic acid was added and haemostasis was re-established. On day 15, rFVIIa was replaced with alternate day infusions of prothrombin complex concentrates (PCCs). On day 21 following the transplant, the patient was discharged, remaining on daily FVIII immune tolerance and thrice-weekly PCC prophylaxis. He remains well 24 months after transplant with an inhibitor titre of 39 BU. This paper describes the second case of cardiac transplantation complicated by haemophilia and an inhibitor, and discusses preoperative planning and operative and postsurgical haemostasis management.

Regression of pulmonary arteriovenous malformations following heart transplantation.

Pulmonary arteriovenous malformations (PAVMs) can occur following caval to pulmonary artery connection, Glenn and/or Fontan procedure, leading to severe cyanosis and exercise intolerance. It is unknown whether these abnormalities regress or persist following heart transplantation (HTx). Twenty patients with failed Fontan or Glenn procedures were screened for PAVMs prior to HTx by contrast echocardiography, selective pulmonary angiography, and pulmonary venous desaturation. Age at transplant, diagnosis, previous operations, time from Glenn to transplant, systemic oxygenation, hemoglobin level, and ventricular function were determined. The clinical course after HTx was characterized in three patients with significant PAVMs. Indications for HTx were exercise intolerance and severe cyanosis in one patient, and cyanosis and ventricular dysfunction in two. Pre-HTx, mean systemic saturation was 67%; mean pulmonary venous wedge saturation was 81%. Post-HTx, oxygen saturations were normal (> 96%) at 14, 40, and 180 days. Contrast echocardiography, performed 1 month to 3.3 yrs after HTx, showed no intrapulmonary shunting in two patients and minimal shunting in one. One patient suffered an embolic stroke from right-to-left shunting post-HTx. All patients are alive and well 35, 71, and 73 months post-HTx. In patients with single ventricle physiology, PAVMs are not an absolute contraindication to HTx. Heart-lung transplant may not be required for these patients.

Two-dimensional echocardiographic assessment of right ventricular function as a predictor of outcome in hypoplastic left heart syndrome.

This study was undertaken to assess the importance of right ventricular function at the time of initial presentation on early and intermediate outcome in patients with hypoplastic left heart syndrome (HLHS). Several studies have attempted to define physiologic risk factors for poor early outcome following the Norwood palliation for HLHS. No clinical or hemodynamic factors including right ventricular function have been found to reliably predict Norwood I operative survival. The relation between initial ventricular function and later survival has not been investigated. To assess the importance of right ventricular (RV) function at the time of initial presentation on outcome in patients with HLHS, systolic function was determined by qualitative and quantitative methods in 60 consecutive patients before surgical intervention. The effects on stage I operative survival, survival to stage II, and overall survival were analyzed. Initial RV function did not impact on stage I survival. However, analysis of later outcome of the stage I survivors showed that those with prestage I RV dysfunction had significantly greater mortality before stage II. Actuarial survival 18 months after Norwood surgery was 93% for patients with initially normal RV function compared with 47% for those with abnormal function (p = <0.005). The relative risk for later mortality was approximately 11 times greater for patients with initial RV dysfunction. Thus, RV dysfunction identifiable soon after initial presentation does not impact on early survival after Norwood I operation for HLHS. Intermediate and overall survival, however, is significantly decreased in patients with initially diminished RV function.

Serial echocardiographic measurements of the pulmonary autograft in the aortic valve position after the Ross operation in a pediatric population using normal pulmonary artery dimensions as the reference standard.

Serial echocardiographic measurements of the annulus and sinus were obtained in children before the Ross operation, and early and late postoperatively. Values were compared with normal standards for the aorta and pulmonary artery (PA). There was no significant difference between PA annulus measurements before surgery and the corresponding autograft immediately afterward (1.73 +/- 0.60 cm preoperatively; 1. 63 +/- 0.58 cm postoperatively, p = NS). Late after surgery the mean annulus diameter was enlarged compared with the normal aorta (DeltaZ 1.9 +/- 2.4), but remained relatively unchanged compared with the normal PA (DeltaZ 0.7 +/- 1.1, p <0.01). In contrast, the autograft sinus was dilated early after surgery (1.83 +/- 0.58 cm preoperatively; 2.18 +/- 0.73 cm postoperatively, p <0.01). Mean sinus Z score further increased compared with both the aorta (DeltaZ 1.3 +/- 1.7) and PA (DeltaZ 1.3 +/- 1.6). Use of standard PA measurements may be important in the assessment of autograft enlargement. Minimal change in autograft Z scores over time suggests that annulus enlargement is mainly due to somatic growth. In contrast, the autograft sinus showed an immediate and continued disproportionate increase in size over time, suggesting that sinus enlargement is largely due to passive dilation.

Hypoplastic left heart syndrome: valuing the survival.

OBJECTIVE: To examine the survival, developmental status, quality of life, and direct medical costs of children with hypoplastic left heart syndrome who have undergone stage I, II, and III reconstructive surgery. METHODS: A total of 106 children underwent staged repair for classic hypoplastic left heart syndrome between February 1990 and March 1999 (stage I: 106; stage II: 49; stage III: 25; 4 converted to heart transplantation). Survival was analyzed by the Kaplan-Meier method. In a cross-sectional study, parents assessed quality of life by completing the Infant/Toddler Child Health Questionnaire or Child Health Questionnaire Parent Format-28; they assessed developmental progress by completing the Ages and Stages Questionnaire. The ratio-of-costs-to-charges method was used to derive hospital costs, and payments were used to capture physician time and wholesale pricing for outpatient medications. RESULTS: Institutional 1-year and 5-year actuarial survivals were 58% and 54%. Birth weight, the need for preoperative inotropic drugs, and surgical experience were predictors of survival. Norwood I patients achieved fewer developmental benchmarks than those who survived to subsequent stages. Child Health Questionnaire Parent Format-28 mean summary scores for physical and psychosocial health were 48.5 +/- 6.3 and 42.8 +/- 9.9. The median inpatient costs for stage I, II, and III repairs were $51,000, $33,892, and $52,183, respectively. Monthly outpatient and readmission costs were less than 10% of total costs. CONCLUSION: A prospective, large-scale study of the comprehensive outcomes of staged repair and transplantation is needed. This study will need to address the longer-term developmental and quality-of-life outcomes, as well as the long-term cost effectiveness of these procedures.

Outcome after orthotopic cardiac transplantation in adults with congenital heart disease.

BACKGROUND: Advances in surgical and medical management have greatly improved long-term survival rates in patients with congenital heart disease (CHD). As these patients reach adulthood, myocardial dysfunction can occur, leading to cardiac transplantation. METHODS AND RESULTS: We reviewed the pretransplantation and posttransplantation courses of 24 patients >18 years old (mean age, 26 years; range, 18 to 56 years) with CHD who received a transplant between January 1985 and September 1998. The relation between preoperative and perioperative risk factors for complications and death was assessed. Single ventricle was the pretransplantation diagnosis for 12 patients (50%), and d-transposition of the great vessels was the diagnosis for 4 patients (16%). Twenty-two patients had a mean of 2 previous operations. At cardiac transplantation, additional surgical procedures were required to correct extracardiac lesions in 18 patients (75%). Refractory heart failure was present in 22 patients, significant cyanosis was present in 7, and protein-losing enteropathy was present in 4. There were 5 early deaths due to bleeding (n=3) and infection (n=2). The Kaplan-Meier survival rate after cardiac transplantation was 79% at 1 year and 60% at 5 years. No anatomic or surgical risk factor was predictive of death. The outcome of patients with CHD who received a transplant was compared with that for patients without CHD (n=788). Mean bypass and ischemic times were significantly longer in patients with CHD than in patients without CHD. Survival rates after transplantation did not differ significantly between patients with and those without CHD (P=0.83). CONCLUSIONS: Successful cardiac transplantation is obtainable in adults with complex CHD, with an outcome similar to that of patients without CHD. A detailed assessment of cardiac anatomy and careful surgical planning are essential to the pretransplantation and posttransplantation management of these patients.

Tracheobronchial anomalies in children with congenital cardiac disease.

OBJECTIVE: To perform preoperative airway evaluations, using radiographic analysis, to review the tracheal anatomy in children with congenital cardiac disease. DESIGN: Prospective. SETTING: A university children's hospital. PARTICIPANTS: One hundred patients. MEASUREMENTS AND MAIN RESULTS: One magnified airway film (high kilovoltage filtered) was performed preoperatively on 100 consecutive children presenting for repair of congenital cardiac disease. Events at intubation, with respect to endotracheal tube size (internal diameter in millimeters) and difficulties with placement of the tube, were recorded. Postoperative morbidity, specifically related to underlying airway anomaly, was documented. Eleven children had positive radiographic findings after review of magnified airway films. Six of 11 patients had evidence of tracheobronchial pathology, and five patients had no tracheal pathology. Difficulties with intubation were noted in two children. No perioperative morbidity was noted in any patient. CONCLUSION: The use of preoperative magnified airway films for tracheal evaluations in children with cardiac disease should be considered.

Usefulness of preoperative echocardiography in predicting left ventricular outflow obstruction after primary repair of interrupted aortic arch with ventricular septal defect.

Residual left ventricular outflow tract (LVOT) obstruction is a significant problem after repair of interrupted aortic arch (IAA) and ventricular septal defect. Resection of subaortic tissue at the time of primary repair, however, is associated with increased morbidity and mortality. We reviewed the preoperative echocardiograms and the postoperative clinical course and echocardiograms of 23 consecutive patients who underwent primary repair of IAA without widening of the subaortic region. Nine patients (39%) developed significant LVOT obstruction (pressure gradient >40 mm Hg). LVOT obstruction was noted postoperatively in 7 of 9 patients by 1 month, 8 of 9 by 2 months, and 9 of 9 by 1 year. On retrospective analysis of the preoperative echocardiograms, the indexed cross-sectional area of the LVOT, the subaortic diameter index, and the subaortic diameter Z score were all significantly smaller in those requiring reintervention (p <0.04, p <0.05, p <0.05, respectively). Of these, indexed cross-sectional area had the least reproducibility and subaortic diameter index the most (coefficient of variation of 26.3% vs 11.2%). In conclusion, most patients who develop significant LVOT obstruction after repair of IAA do so within 1 month of operation. Although subaortic indexed cross-sectional area is the most sensitive predictor of LVOT obstruction after primary repair of IAA, other more simple standardized measurements of the subaortic diameter were comparably predictive and had better reproducibility.

Pediatric cardiac surgery: the effect of hospital and surgeon volume on in-hospital mortality.

OBJECTIVE: To examine the relationship between annual provider (hospital and surgeon) volume of pediatric cardiac surgery and in-hospital mortality. DESIGN: Population-based retrospective cohort study using a clinical database. SETTING: The 16 acute care hospitals in New York with certificate of need approval to perform pediatric cardiac surgery. PATIENTS: All children undergoing congenital heart surgery in New York from 1992 to 1995. MAIN OUTCOME MEASURES: Risk-adjusted mortality rates for various hospital and surgeon volume ranges. Adjustments were made for severity of illness using logistic regression. RESULTS: A total of 7169 cases were analyzed. After controlling for severity of preprocedural illness using clinical risk factors, hospitals with annual pediatric cardiac surgery volumes of fewer than 100 had significantly higher mortality rates (8.26%) than hospitals with volumes of 100 or more (5.95%), and surgeons with annual volumes of fewer than 75 had significantly higher mortality rates (8.77%) than surgeons with annual volumes of 75 or more (5.90%). CONCLUSIONS: Both hospital volume and surgeon volume are significantly associated with in-hospital mortality, and these differences persist for both high-complexity and low-complexity pediatric cardiac procedures.

Double-outlet right ventricle (tetralogy of Fallot type) associated with anomalous origin of the left coronary artery from the right pulmonary artery: report of successful total repair in a 2-month-Old infant.

The case reported herein demonstrates the rare association of double-outlet right ventricle (tetralogy of Fallot type) with anomalous origin of the left coronary artery from the pulmonary artery. It is the first reported successful total surgical repair in an infant.

Outcome after the single-stage, nonfenestrated Fontan procedure.

BACKGROUND: A completed Fontan circulation is the goal in the management of patients with single-ventricle physiology. To achieve this end, a two-stage rather than a single-stage approach is carried out routinely at many centers. Some groups have advocated baffle fenestration for virtually all patients to minimize post-Fontan complications. Other centers perform single-stage Fontan operations and do not fenestrate. Thus controversies have arisen regarding the indications for the staged procedure versus single stage and for fenestration versus no fenestration. METHODS AND RESULTS: The preoperative risk factors and postoperative course were characterized in 61 consecutive patients (median age, 3.3 years) undergoing a single-stage, nonfenestrated Fontan. The patients were followed for 3.5+/-1.9 years. The relationship between preoperative risk factors and mortality and morbidity was assessed. Preoperative risk factors assessed included age <2 years (n=18), branch pulmonary artery stenosis (n=20), elevated mean pulmonary artery pressure >15 mm Hg (n=16), atrioventricular valve regurgitation (n=5), and decreased ventricular function (n=2). Total caval pulmonary anastomosis was performed in 53 patients. Additional surgery was required at the time of the Fontan in 25 patients (41%). The median duration of mechanical ventilation was 1 day; median chest tube drainage was 5.5 days (range, 1 to 35). Oxygen saturation rose significantly postoperatively, from 83% to 95%. Early mortality was 4.9%; one patient died from pacemaker failure 9 months postoperatively, and one patient underwent successful heart transplant 4 months post-Fontan. One- and 5-year actuarial survival was 93%. No preoperative risk factor was associated with a failed Fontan or significant effusions. CONCLUSIONS: A single-stage, nonfenestrated Fontan was performed in a large group of patients with excellent surgical results and intermediate outcome. There is no evidence that a two-stage approach and/or baffle fenestration is required for a large cohort of patients who are candidates for a Fontan operation.

Survival and risk factor analysis for the Norwood procedure for hypoplastic left heart syndrome.

The optimal approach to hypoplastic left heart syndrome (HLHS) is controversial. The palliative Norwood operation, cardiac transplantation, and no surgical intervention have all been advocated. Centers that perform the Norwood operation have met with varied results, and conflicting reports exist regarding factors predictive of stage I outcome. From January 1990 to January 1996, 67 patients with HLHS were admitted with intent to perform the staged Norwood procedure. Fourteen patients did not undergo surgery. In the 53 patients treated surgically, outcome was reviewed, and 10 potential risk factors for first stage mortality were analyzed. Forty-one infants survived the Norwood I operation to hospital discharge (77% of the surgically treated patients and 61% of the entire group, including those who did not undergo operation) with 6 additional deaths 3 to 5 months after operation. Univariate analysis showed cardiopulmonary bypass time and circulatory arrest time to be significant risk factors for hospital mortality. Multivariate analysis revealed only cardiopulmonary bypass time as significant (p <0.01). Of the 15 prenatally diagnosed newborns who underwent surgery, 11 survived (p = 0.72). Ten of 11 patients with preoperative organ damage survived (p = 0.42). Among the 35 bidirectional Glenn (Norwood II) and Fontan (Norwood III) procedures performed, there were 2 deaths. The 5-year actuarial survival for patients who underwent operations was 61%. The Norwood procedure is a favorable option for the infant with HLHS. Surgical survival may be affected by a prolonged cardiopulmonary bypass time, but is not affected by other factors analyzed, including prenatal diagnosis and preoperative organ damage.