Electrocardiographic and Echocardiographic Features That Distinguish Anomalous Origin of the Left Coronary Artery from Pulmonary Artery from Idiopathic Dilated Cardiomyopathy

Many authors have reported noninvasive means of diagnosing anomalous left coronary artery from pulmonary artery (ALCAPA) and differentiating ALCAPA from idiopathic dilated cardiomyopathy (DCM). Systematic evaluation using these noninvasive diagnostic modalities is not available. To distinguish between ALCAPA and DCM using a systematic approach, we examined 23 patients with ALCAPA (age 1 month to 23 years, median 7 months) and 23 patients with DCM (age 5 days to 16 years, median 6.6 months). Standard 12-lead electrocardiograms (ECG) and 2-dimensional (2-D) and color Doppler echocardiograms were performed. A logistic regression model was applied using ALCAPA diagnosis as the dependent variable and ECG and echocardiographic findings as independent variables. A scoring system was created to establish the ALCAPA diagnosis based on results from the logistic regression. On the logistic regression, the ECG feature of QT pattern in aVL (Q wave ≥ 3 mm deep with an inverted T wave) and echocardiographic features of right coronary artery diameter to aortic annulus ratio ≥ 0.14, increased papillary muscle echogenicity, and Doppler color flow of LCA from aorta or pulmonary artery were the most significant differentiating features between the ALCAPA and DCM groups. A scoring system was developed using the previous five variables and assigning a score of 1 to each variable (−1 to Doppler color flow of LCA from aorta). The scoring system had sensitivity of 100% and specificity of 91% for ALCAPA diagnosis. Compared with previous reported diagnostic features in differentiating ALCAPA and DCM, the scoring system had a much higher specificity and positive predictive value. In conclusion, we selected the most useful ECG and echocardiographic features to differentiate between ALCAPA and DCM and created a scoring system to aid clinical diagnosis. This scoring system may be useful in evaluating children with acute congestive heart failure.     

Evaluation of Myocardial Perfusion Using Positron Emission Tomography in Infants Following a Neonatal Arterial Switch Operation

This study was performed to examine the use of positron emission tomography (PET) as a method of evaluating myocardial perfusion after the arterial switch operation for correction of transposition of the great arteries. Eleven asymptomatic patients (median age 2.3 years, range 1.3–4.3 years) post successful neonatal arterial switch repair for transposition underwent cardiac PET scanning using N¹³ ammonia before and after dipyridamole infusion. Reconstructed data from static scans were analyzed for regional perfusion defects before and after pharmacological stress. Simultaneous assessment of coronary flow before and after stress was performed using a Patlak graphical analysis of data from dynamic scans. Results obtained from PET scanning were correlated with patterns of coronary artery anatomy, electrocardiogram (ECG) recordings, and echocardiographic evaluation. PET scanning demonstrated normal distribution of myocardial perfusion before and after stress in all but one patient, who was found to have a discrete inferior transmural perfusion defect. The defect was well correlated with perioperative ECG changes and a complicated postoperative course. Myocardial blood flow before dipyridamole (0.690 ml/min/g) was similar to reported adult rest values. There was a small but significant (p < 0.002) increase in myocardial blood flow after dipyridamole stress with a mean coronary flow reserve of 1.19 (±0.103). Echocardiographic evaluation failed to demonstrate significant wall motion abnormalities in any of the patients. Cardiac PET scanning is a reliable noninvasive method for evaluation of myocardial perfusion in small children. In this study, the incidence of myocardial perfusion defects after the arterial switch operation is lower than previously reported. The data obtained concerning coronary flow and coronary flow reserve after the arterial switch need to be interpreted with caution because normal data in children are not available.     

Percutaneous transluminal angioplasty of the left internal thoracic artery graft: a case report of a child operated on for anomalous origin of the left coronary artery from the pulmonary artery

We report a case of an 8-year-old girl operated on with left internal thoracic artery–coronary artery anastomosis for anomalous left coronary artery from the pulmonary artery, in whom an early stenosis of the graft was successfully treated by percutaneous transluminal angioplasty.     

Surgical Cutdown of the Right Carotid Artery for Aortic Balloon Valvuloplasty in Infancy: Midterm Follow-Up

A vascular approach for balloon aortic dilatation in infants is of major concern due to the high risk of femoral artery injury. To overcome this problem, a surgical right carotid artery (RCA) approach has been advocated. No reports are available on RCA after neonatal cutdown. Since 1990, RCA cutdown has been performed in 29 infants with congenital aortic stenosis. Periprocedural complications included one asymptomatic occlusion and one transient trauma of the stellate ganglion. At a mean follow-up of 4.4 ± 2.2 years from aortic valvuloplasty, ultrasound assessment of morphology and flow of RCA was performed in 17 children. RCA was patent in all patients. The mean ratio of right/left carotid artery diameter was 0.95 ± 0.16 (range 0.65–1.2). The site of surgical incision could be identified in 5 children in the absence of flow disturbance. A 6-year-old asymptomatic girl, who underwent two procedures, had a 35% reduction of RCA diameter at the site of cannulation and turbulent flow at Doppler interrogation, indicating mild obstruction. Our data demonstrate that RCA is well preserved after neonatal surgical cutdown; asymptomatic obstruction can occasionally be present.     

Estimation of Pulmonary Arterial Pressure in the Newborn: Study of the Repeatability of Four Doppler Echocardiographic Techniques

Despite the increasing use of Doppler echocardiographic (DE) techniques to determine pulmonary arterial pressure in the neonate undergoing intensive care, there have been no studies comparing their repeatability in this population. Our objective was to compare the repeatability of four such techniques in neonates. The study was conducted in two regional neonatal units serving the North East of England. Group A (repeatability between observers): Two experienced observers performed detailed DE examinations, one directly after the other. Group B (within observer repeatability/temporal variability): One observer performed two examinations 1 hour apart. Group A comprised 15 preterm babies (26–36 weeks' gestation, 975–2915 g), most with mild respiratory failure; 4 healthy term babies; and 7 with congenital heart disease, in whom tricuspid regurgitation (TR) only was measured. Their ages were 18 hours to 12 days. Group B comprised 11 babies aged 12–64 hours with moderate to severe respiratory failure; 10 were preterm (26–36 weeks, 785–2800 g). We recorded four measurements: (1) Peak velocity of TR in m/s; (2) peak left-to-right ductal flow velocity (PDAmax in m/s); (3) TPV/RVET ratio; and (4) PEP/RVET ratio, where TPV = time to peak velocity at the pulmonary valve, PEP = right ventricular preejection period, and RVET = right ventricular ejection time. The Bland-Altman analysis was used to produce the coefficient of repeatability (CR: 95% confidence limits of repeatability), also expressed as a repeatability index (CR/mean value) and as a number of ``confidence steps'—a measure of sensitivity of the technique to hemodynamic change (range of values within the population/CR). Between-observer and within-observer repeatabilities were similar. Within-observer CR and index (%) results were for TR ± 0.26 m/s (9%); for PDAmax, ± 0.48 m/s (39%); TPV/RVET 0.1:1.0 (34%), PEP/RVET 0.12:1.00 (36%). TR and PDAmax had the largest number of confidence steps in the expected range of values (TR 8.5; PDA max 6.5; TPV/RVET 3.2; PEP/RVET 3.2). The most repeatable technique was TR, but PDAmax would also be useful for a serial study owing to the potential for large change. Systolic time interval ratios were less repeatable and likely to be less sensitive indicators of hemodynamic change.     

Transcarotid Balloon Valvuloplasty with Continuous Transesophageal Echocardiographic Guidance for Neonatal Critical Aortic Valve Stenosis: An Alternative to Surgical Palliation

Neonatal critical aortic valve stenosis is a life-threatening malformation if untreated. Before the late 1980s, the preferred treatment was surgical valvotomy; however, operative mortality was high. Early reports of transcatheter balloon dilation were encouraging, although femoral artery damage and aortic valve insufficiency were procedural limitations. With new balloon catheter technology, transumbilical, transvenous, and transcarotid approaches have been advocated, although a comparison with recent surgical results has not been performed. We compared all neonates who presented to our institution since 1985 with the diagnosis of critical aortic stenosis. Ten patients underwent surgical transventricular valvotomy and 13 patients underwent balloon valvuloplasty via a right carotid cutdown with continuous transesophageal echocardiographic guidance. Prior to intervention, all patients had either left ventricular dysfunction, an aortic valve gradient >100 mmHg, significant mitral valve insufficiency, and/or ductal dependent systemic blood flow. All patients had successful relief of aortic valve obstruction with normalization of left ventricular function and successful discontinuation of prostaglandin E₁. Use of continuous transesophageal echocardiographic guidance resulted in fluoroscopic exposure of only 12 ± 8 minutes. At the latest follow-up, a similar proportion of patients has required additional aortic valve procedures (38% vs 25%) and overall mortality (20% vs 15%) is similar. In the transcarotid group, 9 of 13 patients (69%) have a normal appearing right carotid artery by Duplex imaging, and no neurologic events have been reported. Balloon aortic valvuloplasty via a right transcarotid approach is safe, simplifies crossing the valve, and is effective for the initial palliation of neonatal critical aortic stenosis. The use of transesophageal echocardiographic guidance reduces fluoroscopy exposure, enables accurate assessment of hemodynamics without catheter manipulation or angiography, and avoids femoral artery injury.     

Real-Time Magnetic Resonance Imaging: Diagnostic and Interventional Applications

The advent of ultra-fast imaging techniques has extended the utility of magnetic resonance imaging (MRI) from a static and purely diagnostic status to an imaging modality ideally suited for a number of therapeutic applications. These advances—along with the recent development and refinement of miniature intravascular imaging catheters and MRI-compatible guidewires, balloon catheters, and radiofrequency ablation catheters—have created an exciting forum of novel approaches for detecting and treating both acquired and congenital cardiovascular disease. This review covers the current state of the art in fast cardiovascular MRI, catheter-tracking techniques for MR fluoroscopy, and currently available interventional MRI systems. Early diagnostic and therapeutic applications, such as high-resolution intravascular and intracardiac imaging, balloon angioplasty, stent placement, and radiofrequency ablation techniques, are discussed and extended to several potential approaches specific to pediatric cardiac therapeutic catheterization. Lastly, saftey aspects of MR-guided interventional procedures are presented.     

Progressive Congenital Valvar Aortic Stenosis During Infancy: Five Cases

We report our experience with asymptomatic valvar aortic stenosis diagnosed during infancy. During the period between November 1, 1986 and October 31, 1992 a total of 13 infants were diagnosed with asymptomatic aortic stenosis, 5 of whom showed rapid progression over the first 2 years of life. Two of these asymptomatic infants had severe aortic stenosis by 2 months of age, requiring intervention. We agree that aortic stenosis is a progressive lesion even in mild cases, but we emphasize the need for close clinical and echocardiographic follow-up of these asymptomatic children during infancy to prevent congestive heart failure and sudden death.     

Circulating Cardiac Troponin I Levels in Kawasaki Disease

In addition to the vascular findings of Kawasaki disease (KD), clinical, electrocardiographic, and/or echocardiographic signs of myocarditis are recognizable in the acute phase of KD in many patients. The mechanism of myocarditis and an association with the development of subsequent coronary artery abnormalities in KD is unknown. Previous studies of serum cardiac troponin I (cTnI) measurements in pediatric populations have suggested a possible utility of measurements in diagnosis and follow-up of KD. We designed a retrospective study to evaluate cTnI measurements during acute KD and to assess the predictive value of cTnI measurements in acute KD for the subsequent development of coronary artery abnormalities. Twenty-nine children were studied. Group 1 consisted of 15 KD patients who developed coronary artery abnormalities as detected by transthoracic echocardiographic evaluation. Group 2 consisted of 14 KD patients with persistently normal coronary artery findings on echocardiograms. A control group consisted of 11 children, none of whom were known to have had clinical findings of KD or myocarditis. The mean cTnI values for all three groups were lower than the values suggestive of cardiac damage: group 1 = 0.11 ± 0.16 ng/ml, group 2 = 0.15 ± 0.34 ng/ml, and control = 0.04 ± 0.08 ng/ml. The current study demonstrates that there is no significant elevation of cTnI in KD patients. Additionally, there is no correlation between cTnI measurements and the finding of myocarditis, as reflected by decreased cardiac function, or the subsequent development of coronary artery abnormalities.     

Aberrant Left Coronary Artery Arising from the Right Sinus of Valsalva with a Right Coronary Arteriovenous Malformation

An 11-year-old boy presented with myocardial ischemia and was found to have an aberrant left main coronary artery from the right sinus of Valsalva coursing between the aorta and pulmonary artery, as well as a small arteriovenous malformation from a right atrial branch of the right coronary artery to the right atrium. Distinctive echocardiographic findings were supported by angiographic and magnetic resonance imaging studies. Treadmill and scintigraphic stress testing were normal. Corrective surgery was accomplished by a modified technique to unroof the intramural proximal course of the left coronary artery, without postoperative complications. The anatomy and pathophysiology of this rare coronary lesion are reviewed.     

Tetralogy of Fallot with Major Aortopulmonary Collaterals: Early Total Repair

Tetralogy of Fallot with pulmonary atresia and major aortopulmonary collaterals is a complex lesion distinguished by marked heterogeneity of pulmonary blood supply. Over the past two decades, investigators have developed various approaches to the management of this anomaly generally based on the concept of staged unifocalization of pulmonary blood supply. Although such approaches may represent an improvement on the natural history of this lesion, they remain inadequate for a substantial portion of patients born with tetralogy of Fallot and major aortopulmonary collaterals. Since 1992, our approach has been to perform one-stage complete unifocalization through a midline approach in all but a few extremely complicated patients. We aim to repair these patients early in infancy, with an emphasis on native tissue–tissue reconstruction, in order to optimize prospects for survival with a good functional outcome in as many patients as possible. In this review, we present our philosophy and our experience with unifocalization and repair in 72 patients.     

X-Chromosomal (p21) Muscular Dystrophy and Left Ventricular Diastolic and Systolic Function

In order to screen for cardiac abnormalities, we prospectively studied 15 patients (age 8–25 years, mean 15.5 years) with Duchenne's (DMD) (n= 9) and Becker's (BMD) (n= 6) muscular dystrophy using the echocardiogram. Data were compared to a control group of 92 healthy individuals (age 7.9–25 years, mean 14.3 years). Left ventricular filling in diastole showed a different pattern when comparing echocardiographic Doppler results in patients and controls: Patients had lower peak velocity of early left ventricular diastolic filling (E-vmax)(P < 0.0001) and smaller time velocity integral of the E-wave (E-tvi)(P < 0.0001). In contrast, the atrial component (A-vmax, A-tvi) of diastolic filling in DMD/BMD showed no significant difference to controls. The mean area of the mitral valve orifice was significantly larger in patients (P < 0.0001) without presence of mitral regurgitation. Systolic left ventricular function was significantly impaired in the DMD/BMD group; we found lower heart rate corrected fiber shortening velocity VCFc (P < 0.001) and higher peak systolic wall stress (P < 0.001) in DMD/BMD. In 8 of 15 patients, peak systolic wall stress was above 95th percentile of controls. In 6 of 15 patients, VCFc was lower than the 5th percentile of controls. Systolic and diastolic myocardial impairment was found even in young patients and at low stages of disability—equally among patients with DMD or BMD. Diastolic left ventricular impairment predominantly affected the early diastolic filling, but atrial compensation was poor. Peak systolic wall stress measurements were particularly useful in patients with CMP, reflecting the left ventricular afterload.     

Branch Pulmonary Artery Growth After Blalock–Taussig Shunts in Tetralogy of Fallot and Pulmonary Atresia with Ventricular Septal Defect: A Retrospective, Echocardiographic Study

We performed a retrospective echocardiographic study in tetralogy of Fallot (TOF) or pulmonay atresia with ventricular septal defect (PA&VSD) to evaluate the effects of Blalock–Taussig shunt on branch pulmonary artery growth. There were 35 patients with TOF and 11 with PA&VSD. We measured the right and left pulmonary artery area index and also the combined pulmonary artery area index, both before and after shunt operation. The mean ± SD of these three variables before the shunt operation in the TOF group were 63.5 ± 22.5, 57.8 ± 24.9, and 121.4 ± 42.8 mm²/m²; after shunt operation they were 98.5 ± 33.6, 85.9 ± 31.9, and 184.0 ± 59.8 mm²/m², respectively (p values <0.0001, <0.0002, and <0.0001, respectively). In the PA&VSD group the comparable values before shunt operation were 66.5 ± 16.0, 55.4 ± 10.6, and 120.9 ± 26.9 mm²/m² and after shunt operation were 90.5 ± 22.9, 77.2 ± 24.1, and 166.6 ± 44.4 mm²/m², respectively (p values <0.0006, <0.014, and <0.002, respectively). We also examined the effect of distensibility of pulmonary arteries by comparing the percentage change in size of the combined pulmonary artery area index in the first 4 months after shunt with those after this time (p < 0.023). There were no significant differences between left- and right-sided shunts, origin and distal pulmonary artery growth, and the TOF and PA&VSD groups.     

Situs Inversus Totalis and Corrected Transposition of the Great Arteries {I,D,D} in Association with a Previously Unreported Vascular Ring

A 3-month-old girl with ``noisy breathing' was found to have situs inversus totalis, corrected transposition of the great arteries {I,D,D}, and a vascular ring. The ring was composed of a left aortic arch with normal branching pattern and a right ligamentum arteriosum that extended from a diverticulum off the descending aorta and coursed retroesophageal and to the right to join the pulmonary artery. There was no circumflex component of the aorta or aberrant subclavian artery. The descending aorta was left sided. Compression of the esophagus and trachea was noted on contrast esophagram, magnetic resonance imaging (MRI), and at the time of surgery to divide the vascular ring. In association with her corrected transposition, the patient also was shown to have a mild Ebstein's deformity of the right-sided (systemic) atrioventricular valve and electrocardiographic evidence of Wolfe–Parkinson–White syndrome. The combination of situs inversus totalis, corrected transposition of the great arteries {I,D,D}, and an aortic arch anomaly has not been previously reported. In addition, the aortic arch anomaly suggested by MRI imaging and confirmed at surgery has previously only been postulated to exist but to our knowledge never reported.     

Diagnostic and Perinatal Management of Fetal Extrasystole

Fifty fetuses referred to the Polish Mother's Memorial Hospital for fetal echocardiography between January 1, 1991 and June 1, 1995 were evaluated. The mean fetal gestational age at the time of diagnosis of arrhythmia was 34.1 weeks, and the mean gestational age at the time of delivery was 38.7 weeks. Checkup echocardiographic examinations were performed every 10–14 days, for a mean 2.4 studies per fetus. In most cases (48/50, 96%), premature atrial contractions were present during the first echocardiography examination. The fetal heart study was normal in 30 cases; in 7 (14%) there was tricuspid valve regurgitation, in 7 (14%) an atrial septal aneurysm, in 4 congenital heart defects, in 1 myocardial hypertrophy, and in 1 disproportion in the four-chamber view. Of the 50 fetuses, 43 underwent regular echocardiographic monitoring alone; in 7 cases, based on the presence of additional echocardiographic findings, pharmacotherapy was applied (digoxin, verapamil, or both). Three neonates died after delivery owing to malformations in two cases (one critical aortic stenosis, one spina bifida plus hygroma colli) and due to myocarditis in one case. In six of seven newborns treated in utero, myocarditis was diagnosed after birth (including the one with neonatal demise). Most of the newborns were in good condition after birth, their mean Apgar score being 8.6 and the mean birth weight 3259 g. We concluded that most extrasystoles represent an isolated anomaly, not affecting the fetal condition. Their presence should not influence the obstetric care and may require only echocardiographic monitoring. In most of our cases the premature contractions subsided after birth, although sometimes they preceded fetal supraventricular tachycardia or appeared after congenital myocarditis.     

Reversible Cardiomyopathy Secondary to α-Interferon in an Infant

Interferon-α (IFN-α) is a biological response modifier with antiviral and tumoral effect that is used in the treatment of chronic myelogenous leukemias. Adverse effects are well documented and cardiovascular disturbances mostly include hypotension and tachycardia and rarely cardiomyopathy. We report on an infant with chronic myelomonocytic leukemia (CML) diagnosed at 3 months of age who was treated with increasing IFN-α dosage (2.5–5.5 million U/m²/day) given subcutaneously for 7.5 months. At that age, he presented anorexia, general malaise, and nocturnal sweating for about a week, followed by respiratory distress and tachycardia. Diagnosis of congestive heart failure was suspected and documented by cardiomegaly and echographic changes of left ventricular dilated cardiomyopathy, with a 40% left ventricular ejection fraction (EF) and 20% fractional shortening (FS). He was treated with digoxin, furosemide, and angiotensin converting inhibitors, and IFN-α was discontinued. Progressive improvement of cardiac function was observed within 7 months of the events with normalization of the echocardiographic findings (EF 60%, FS 31%). We should emphasize the possibility of severe and reversible cardiac toxicity of IFN-α in infancy.     

Severe Left Ventricular Dysfunction and Arrhythmias as Complications of Gram-Positive Sepsis: Rapid Recovery in Children

Severe left ventricular dilatation and dysfunction in children may be associated with poor outcome in as many as 45% of cases. The prognosis for children with poor left ventricular function or arrhythmias associated with septic shock may be better, however, this has been inadequately studied. We report the favorable outcome of three children who presented with Gram-positive sepsis and significant cardiovascular compromise—two with severely dilated, poorly contractile left ventricle, and one with mild left ventricular dysfunction and incessant, malignant, and rapid atrial and ventricular arrhythmias. Our experience with these patients shows that complete and rapid resolution of these complications may be achieved with aggressive therapy.     

Atypical Bland–White–Garland Syndrome with Stenosis of the Origin of the Left Coronary Artery: Catheter Intervention After Mammary Artery Bypass Stenosis and Residual Fistula to the Pulmonary Trunk

A 16-year-old boy with anomalous origin of the left coronary artery from the pulmonary artery, Bland–White–Garland syndrome, underwent a mammary artery bypass grafting to the left coronary artery (LCA) together with closure of the stenosed origin of the left coronary artery. A residual LCA to pulmonary artery fistula and stenosis of the shunt at the implantation site developed that resulted in a dominant perfusion of the LCA from the right coronary artery. Interventional catheterization was performed with stenting of the LCA mammary artery anastomosis and subsequent coil occlusion of the residual fistula. After this intervention the LCA was exclusively perfused by the mammarian bypass with no residual leak to the pulmonary artery.     

Diagnostic and Cost Effectiveness of Telemonitoring the Pediatric Pacemaker Patient

Although recommended as part of a comprehensive pacemaker follow-up protocol, the diagnostic and cost-effectiveness of routine telephone monitoring (TM) in children in the United States is largely unknown. Patient age and size with inherent age-related problems and potential inability to correlate symptoms with pacemaker performance places the pediatric patient in a unique category, different from that of the adult. A total of 96 patients, ages 0.2–32.0 years (mean 12.0 years) were followed for 3 years after pacemaker implant with both routine monthly and anytime emergency TM. A total of 1372 routine transmissions were performed of a recommended 3456 (40% patient compliance). Of these, 99% showed normal rhythm or pacemaker function. The remaining 1% demonstrated asymptomatic pacemaker dysfunction requiring intervention or new-onset dysrhythmias. A total of 75 emergency transmissions were undertaken for patient/parent-perceived problems, only 8% of which showed pacemaker dysfunction or dysrhythmias. The sensitivity of patient/parent capacity to detect pacemaker problems or dysrhythmias based on clinical findings was 29%, with a positive predictive value of 8%. The specificity of routine monthly TM to screen for asymptomatic pacemaker dysfunction or new-onset dysrhythmias was 95%, with a negative predictive value of 99%. TM was effective (p < 0.001) for correlating the presence or absence of pacemaker problems with subjective complaints at any patient age. Financial charges for use of TM were significantly less (p < 0.01) than comparable outpatient visits.     

Effects of Age and Respiration on Right Ventricular Diastolic Filling Patterns in Normal Children

Right ventricular diastolic filling was assessed in 88 normal Chinese children using Doppler echocardiographic interrogation of diastolic transtricuspid valve flow. Any influences of age and respiration on right ventricular diastolic filling were also investigated. The results showed that age-dependent differences were apparent for filling times, associated with the decrease in heart rate with increasing age. In addition, peak transtricuspid flow velocities were markedly greater in inspiration than in expiration, with corresponding increases in filling times and velocity–time integrals. The influence of age and respiration on transtricuspid flow parameters should be considered in the evaluation of right ventricular diastolic function by Doppler echocardiography. We believe that measurements should be standardized for respiratory phase and that right ventricular diastolic function parameters should be taken at end-inspiration and end-expiration, respectively.