Assessment of Diastolic Function in Single-Ventricle Patients After the Fontan Procedure.

BACKGROUND: Patients with functional single ventricles after the Fontan procedure have abnormal cardiac mechanics. The aims of this study were to determine factors that influence diastolic function and to describe associations of diastolic function with current clinical status. METHODS: Echocardiograms were obtained as part of the Pediatric Heart Network Fontan Cross-Sectional Study. Diastolic function grade (DFG) was assessed as normal (grade 0), impaired relaxation (grade 1), pseudonymization (grade 2), or restrictive (grade 3). Studies were also classified dichotomously (restrictive pattern present or absent). Relationships between DFG and pre-Fontan variables (e.g., ventricular morphology, age at Fontan, history of volume-unloading surgery) and current status (e.g., systolic function, valvar regurgitation, exercise performance) were explored. RESULTS: DFG was calculable in 326 of 546 subjects (60%) (mean age, 11.7 ± 3.3 years). Overall, 32% of patients had grade 0, 9% grade 1, 37% grade 2, and 22% grade 3 diastolic function. Although there was no association between ventricular morphology and DFG, there was an association between ventricular morphology and E', which was lowest in those with right ventricular morphology (P < .001); this association remained significant when using Z scores adjusted for age (P < .001). DFG was associated with achieving maximal effort on exercise testing (P = .004); the majority (64%) of those not achieving maximal effort had DFG 2 or 3. No additional significant associations of DFG with laboratory or clinical measures were identified. CONCLUSIONS: Assessment of diastolic function by current algorithms results in a high percentage of patients with abnormal DFG, but few clinically or statistically significant associations were found. This may imply a lack of impact of abnormal diastolic function on clinical outcomes in this cohort, or it may indicate that the methodology may not be applicable to pediatric patients with functional single ventricles.

Screening for aortic aneurysm after treatment of coarctation.

Isolated coarctation of the aorta (CoA) occurs in 6-8 % of patients with congenital heart disease. After successful relief of obstruction, patients remain at risk for aortic aneurysm formation at the site of the repair. We sought to determine the diagnostic utility of echocardiography compared with advanced arch imaging (AAI) in diagnosing aortic aneurysms in pediatric patients after CoA repair. The Congenital Heart Databases from 1996 and 2009 were reviewed. All patients treated for CoA who had AAI defined by cardiac magnetic resonance imaging (MRI), computed tomography (CT), or catheterization were identified. Data collected included the following: type, timing, and number of interventions, presence and time to aneurysm diagnosis, and mortality. Patients were subdivided into surgical and catheterization groups for analysis. Seven hundred and fifty-nine patients underwent treatment for CoA during the study period. Three hundred and ninety-nine patients had at least one AAI. Aneurysms were diagnosed by AAI in 28 of 399 patients at a mean of 10 ± 8.4 years after treatment. Echocardiography reports were available for 380 of 399 patients with AAI. The sensitivity of echocardiography for detecting aneurysms was 24 %. The prevalence of aneurysms was significantly greater in the catheterization group (p < 0.05) compared with the surgery group. Aneurysm was also diagnosed earlier in the catheterization group compared with the surgery group (p = 0.02). Multivariate analysis showed a significantly increased risk of aneurysm diagnosis in patients in the catheterization subgroup and in patients requiring more than three procedures. Aortic aneurysms continue to be an important complication after CoA repair. Although serial echocardiograms are the test of choice for following-up most congenital cardiac lesions in pediatrics, our data show that echocardiography is inadequate for the detection of aneurysms after CoA repair. Because the time to aneurysm diagnosis was shorter and the risk greater in the catheterization group (particularly for patients requiring more than one procedure), surveillance with cardiac MRI or CT should begin earlier in these patients.

Safety and imaging quality of MRI in pediatric and adult congenital heart disease patients with pacemakers.

BACKGROUND: Magnetic resonance imaging (MRI) is a standard of care in evaluating many disease processes. Given concerns about device damage or movement, programming changes, lead heating, inappropriate pacing, and image artifact, MRI is contraindicated in pacemaker patients. Despite this, studies have demonstrated safety and efficacy of MRI in adults with acquired heart disease and endocardial pacing leads. We sought to evaluate MRI use in congenital heart disease (CHD) patients with predominantly epicardial pacing leads. METHODS: From July 2007 to October 2008, MRI (1.5 Tesla) was performed in 11 patients without alternative imaging modality who were not pacemaker dependent or possessing abandoned leads. Pacing was disabled during MRI. An electrophysiologist monitored electrocardiogram and hemodynamic parameters throughout each study. Device and lead function were evaluated before and after MRI, and at subsequent clinic visits. RESULTS: Eleven MRIs (four cardiac, seven noncardiac) were performed in eight patients. Mean patient age was 16.5 +/- 9.2 years (range 1.7-24.5) with five patients under the age of 16 years. Diagnoses included structural CHD in six patients and long QT syndrome and congenital heart block in one each. There were three dual- and five single- (three atrial, two ventricular) chamber devices, two endocardial, and nine epicardial leads. No inappropriate pacing or significant change in generator or lead parameters was noted. All MRI studies were of diagnostic quality. CONCLUSION: Diagnostic quality MRI can be performed safely in nonpacemaker-dependent CHD patients with predominantly epicardial leads. Further studies will define safe practice measures in this population, as well as in CHD patients with pacemaker dependency.

Late gadolinium enhancement: precursor to cardiomyopathy in Duchenne muscular dystrophy?

BACKGROUND: Progressive cardiomyopathy is a common cause of death in Duchenne muscular dystrophy (DMD), presumably secondary to fibrosis of the myocardium. The posterobasal and left lateral free wall of the left ventricle (LV) are initial sites of myocardial fibrosis pathologically. The purposes of this study were to assess whether cardiac magnetic resonance imaging (CMRI), utilizing late gadolinium enhancement (LGE), could identify fibrosis in selective areas of the myocardium, and to assess the relationship of the presence and extent of fibrosis to LV function. METHODS: The cardiology databases at Primary Children's Medical Center and Cincinnati Children's Hospital Medical Center were reviewed to identify patients with DMD who had undergone a CMRI within the last 2 years. Age, LV ejection fraction, LV mass, presence and location of LGE were documented. Volumes were measured using MASS (Medis, Inc.) to calculate ejection fraction and mass. LGE images were acquired and when positive, customized computer assisted sizing of the areas of late gadolinium enhancement were performed on all slices. Normal function was defined as LV ejection fraction >54%. RESULTS: A total of 74 patients with DMD had complete data sets (median age 13.7 years, range 7.7-26.4). Twenty-four patients (32%) had LGE involving the posterobasal region of the LV in a sub-epicardial distribution. Those patients with more involvement had spread to the inferior and left lateral free wall with progressive transmural fibrous replacement. There was relative sparing of the interventricular septum and right ventricle. Patients with LGE were significantly older than those without (mean age 16.4 vs 12.9 years, P < 0.001). LGE was positively associated with BSA-adjusted LV mass, LV end-diastolic volume, LV end-systolic volume, and RV end-systolic volume but inversely correlated with ejection fraction of the LV (P < 0.001) and RV (P = 0.004). CONCLUSIONS: LGE by CMRI is able to detect fibrosis in selective regions of myocardium in patients with DMD. Unfavorable LV remodeling, with a corresponding decreased ejection fraction, is associated with the presence of LGE. Serial studies are warranted to determine if LGE precedes a decrease in function, and if early medical management is useful in preventing progression once LGE is documented.

Intermediate-term results of repair for aortic, neoaortic, and truncal valve insufficiency in children.

OBJECTIVE: Repair of aortic valve insufficiency is difficult, and durability is relatively unknown in children. This study evaluates the intermediate-term results of repair of the systemic semilunar valve, including the native aortic valve, neoaortic valve (anatomic pulmonary), and truncal valve. METHODS: We reviewed the records of 54 children (aged 2 days to 18 years) who underwent repair of the functional aortic valve for moderate or greater insufficiency from 1991 to 2005. Valve anatomy was tricuspid aortic in 26 patients, bicuspid aortic in 11 patients, tricuspid neoaortic in 9 patients, bicuspid neoaortic in 1 patient, and truncal valve in 7 patients. Multiple surgical techniques were used in most of the 54 patients, including leaflet plication in 17, leaflet repair in 15, commissuroplasty in 32, pericardial cusp augmentation in 8, and sinus of Valsalva reduction in 3. RESULTS: There was 1 early death and no late deaths. Actuarial freedom from reoperation was 68% at 5 years and 58% at 10 years. Freedom from aortic valve replacement was 82% at 5 years and 73% at 10 years. Duration of cardiopulmonary bypass was the most significant risk factor for reoperation with multivariate analysis. Of the 40 patients who have not undergone reoperation, 37 have had follow-up echocardiograms with the latest study (4.5 +/- 4.2 years) demonstrating trace to 1+ insufficiency in 23 patients, 1 to 2+ in 12 patients, 2 to 3+ in 1 patient, and 3 to 4+ in 1 patient. CONCLUSION: Repair of the insufficient systemic semilunar valve offers acceptable 10-year freedom from reoperation and functional results, and should be considered for most children.

Anomalous right coronary artery from the pulmonary artery: noninvasive diagnosis and serial evaluation.

Isolated anomalous origin of the right coronary artery from the main pulmonary artery (ARCAPA) is a rare congenital cardiac malformation. We reviewed the current literature and found only 31 patients with ARCAPA. We report the first case that was diagnosed and followed on a noninvasive basis with cardiovascular magnetic resonance after surgical re-implantation. This report of a patient with ARCAPA showed resolving coronary artery sizes secondary to decreased pulmonary steal. Cardiovascular magnetic resonance is an accurate and reliable imaging modality that allows serial noninvasive follow up in patients with coronary artery anomalies.

Usefulness of real-time navigator magnetic resonance imaging for evaluating coronary artery origins in pediatric patients.

Navigator coronary magnetic resonance imaging (MRI) was evaluated in assessing coronary artery origins in a pediatric and adolescent population. Sixty-five consecutive infants, children, or adolescents (age range 11 days to 21 years) were referred for MRI evaluations to assess coronary artery origins. Coronary artery origins were unambiguously delineated in 62 of 65 patients. In 3 patients, irregular arrhythmias precluded cardiac gating of the magnetic resonance acquisition. Two patients had anomalous coronary artery origins detected. Twenty-six patients required sedation for the studies. Free-breathing 3-dimensional MRI with real-time navigator correction is a robust method for delineating the coronary artery origins in pediatric and adolescent patients.

Myocardial performance index with sevoflurane-pancuronium versus fentanyl-midazolam-pancuronium in infants with a functional single ventricle.

BACKGROUND: Patients with congenital heart disease characterized by a functional single ventricle make up an increasing number of patients presenting for cardiac or noncardiac surgery. Conventional echocardiographic methods to measure left ventricular function, i.e., ejection fraction, are invalid in these patients because of altered ventricular geometry. Two recently described Doppler echocardiographic modalities, the myocardial performance index and Doppler tissue imaging, can be applied to single-ventricle patients because they are independent of ventricular geometry. This study assessed the changes in myocardial performance index and Doppler tissue imaging in response to two anesthetic regimens, fentanyl-midazolam-pancuronium and sevoflurane-pancuronium. METHODS: Thirty patients aged 4-12 months with a functional single ventricle were randomized to receive fentanyl-midazolam or sevoflurane. Myocardial performance index and Doppler tissue imaging were measured by transthoracic echocardiography at baseline and two clinically relevant dose levels. RESULTS: Sixteen patients receiving sevoflurane and 14 receiving fentanyl-midazolam were studied. Myocardial performance index was unchanged from baseline with either agent (fentanyl-midazolam: 0.50 +/- 15 baseline vs. 0.51 +/- 0.15 at dose 2; sevoflurane: 0.42 +/- 0.14 baseline vs. 0.46 +/- 0.09 at dose 2). Doppler tissue imaging S (systolic)- and E (early diastolic)-wave velocities in the lateral ventricular walls at the level of the atrioventricular valve annulus were unchanged in the sevoflurane group; however, both Doppler tissue imaging S- and E-wave velocities were decreased significantly from baseline at dose 1 and dose 2 with fentanyl-midazolam, consistent with decreased longitudinal systolic and diastolic ventricular function. CONCLUSIONS: Myocardial performance index, a global measurement of combined systolic and diastolic ventricular function, is not affected by commonly used doses of fentanyl-midazolam or sevoflurane in infants with a functional single ventricle.

Anatomic reconstruction for recurrent aortic obstruction in infants and children.

BACKGROUND: Patients undergoing operative repair of aortic obstruction are at a lifelong risk of recurrent obstruction, and there is controversy regarding the optimal surgical technique. We have used an alternative strategy for recurrent aortic obstruction, typically involving anatomic reconstruction by means of a median sternotomy, and describe our techniques and results. METHODS: Twenty-one patients presented with recurrent aortic arch obstruction. Mean age and weight were 7.8 +/- 5.4 years (range, 0.21 to 15.2 years) and 30.6 +/- 21.8 kg (range, 3.6 to 90 kg), respectively. Recurrence involved the aortic arch to some degree in each case, as the mean preoperative transverse aortic arch z score was -2.9 +/- 1.6 (range, -7.0 to 0.1). Thoracotomy was possible in 2 patients, using re-resection with end-to-end anastomosis (n = 1) and patch aortoplasty (n = 1). The remaining 19 patients required median sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest for complete relief of obstruction by aortic arch advancement (n = 10), patch aortoplasty (n = 8), or interposition grafting (n = 1). RESULTS: There was 1 hospital death. Invasive blood pressure monitoring revealed no residual arm-to-leg gradient in 19 patients and a 20-mm Hg gradient in 2 patients. There have been no late deaths. No patients have undergone subsequent aortic intervention, and all are asymptomatic up to 85 months postoperatively. Two patients are currently followed with a 10-mm Hg arm-to-leg blood pressure gradient. CONCLUSIONS: Anatomic reconstruction for recurrent aortic obstruction can be safely accomplished in the majority of patients. We favor median sternotomy because of the ability of establishing cardiopulmonary bypass, the facility of anatomic reconstruction techniques, and the ability to repair concomitant cardiovascular lesions.

The Warden procedure for partially anomalous pulmonary venous connection to the superior caval vein.

PURPOSE: When there is partially anomalous pulmonary venous connection to the superior caval vein, intracardiac repair alone can result in obstruction. Although the Warden procedure involving translocation of the superior caval vein is commonly performed as an alternative to atriocavoplasty, follow-up of a larger number of patients in the modern era is lacking. We report and discuss the experience of a single institution with the Warden procedure for correction of partially anomalous pulmonary venous connection to the superior caval vein. METHODS: Since 1995, all 16 patients presenting with partially anomalous pulmonary venous connection to the superior caval vein underwent the Warden procedure at a mean age of 7.1 +/- 4.2 years, with a range from 0.2 to 14.3 years, and a mean weight of 24.7 +/- 14.0 kg, with a range from 4.1 to 52.9 kg. There were 9 males and 7 females. In 8 patients, we performed 10 concomitant procedures, including closure of an atrial or ventricular septal defect in 7, and advancement of the aortic arch in the other. RESULTS: There were no deaths, and only one episode of postoperative sinus bradycardia with intermittent junctional rhythm, which resolved spontaneously during temporary atrial pacing. All patients were discharged home in normal sinus rhythm at an average of 4.1 +/- 2.2 days after the procedure, with a range from 2 to 10 days. All are currently in the first grade of the New York Heart Association up to 5.6 years postoperatively. There is currently no evidence of sinus nodal dysfunction, nor obstruction of the superior caval vein, in any patient. CONCLUSION: The Warden procedure for partially anomalous pulmonary venous connection to the superior caval vein produces excellent results, preserves the function of the sinus node, and should be routinely considered for the repair of this lesion.