Novel Technique to Evaluate Pulmonary Vascular Resistance in a Patient With Aortopulmonary Window.

We report a case of a 15-month-old female presenting with a large aortopulmonary window during a medical mission. The optimal surgical correction for this patient would be based on an estimation of her pulmonary vascular reactivity. This report details the use of antegrade/retrograde flow ratios using Doppler measurements in the proximal descending aorta at baseline and while receiving 100% oxygen. A large increase in the proportion of retrograde flow under the 100% oxygen condition suggested a reactive pulmonary vascular bed. She underwent a complete repair with patch closure of the aortopulmonary window. A postoperative echocardiographic assessment showed near normal right ventricular pressures.

Mucocutaneous lymph node syndrome (Kawasaki disease): delayed aortic and mitral insufficiency secondary to active valvulitis.

A 2 8/12 year old girl with acute mucocutaneous lymph node syndrome (Kawasaki disease), presented 17 months later with a new onset of mitral and aortic insufficiency. Congestive heart failure rapidly developed and double valve replacement was performed. Pathologic study of the excised valve tissue disclosed active valvulitis. This is the first report of late onset aortic and mitral valvulitis associated with Kawasaki disease.

Successful surgical repair of aortic atresia associated with normal left ventricle.

Surgical repair of aortic atresia with a large ventricular septal defect and a normally developed left ventricle was accomplished in a 14 month old infant. Palliative surgery at age 23 days consisted of bilateral banding of pulmonary artery branches and replacement of the ductus arteriosus with a Goretex conduit. Corrective surgery was accomplished by closure of the ventricular septal defect, insertion of a valved conduit between the apex of the left ventricle and the subdiaphragmatic aorta, removal of the pulmonary artery bands and division of the pulmonary-aortic conduit. The patient has a mild coarctation of the aorta and remains asymptomatic at 2 years of age.

Abnormal systemic venous Doppler flow patterns in atrial tachycardia in infants.

Congestive heart failure due to atrial tachycardia in the neonate may be caused in part by altered preload and changes in diastolic flow characteristics. During atrial tachycardia, venous flow reversal is present. Onset of flow reversal is associated with a ventriculoatrial interval. Decreased tricuspid valve inflow mean velocity and time velocity integral, decreased diastolic duration, and delayed diastolic onset were present during tachycardia when compared with sinus rhythm.

Usefulness of echocardiographic evidence of pericardial effusion and mitral regurgitation during the acute stage in predicting development of coronary arterial aneurysms in the late stage of Kawasaki disease.

In 28 patients with Kawasaki disease, the relation of specific echocardiographic findings identified during the acute study of the illness, including valvular regurgitation, to development of coronary aneurysms was evaluated. Initial studies were performed at the time of clinical presentation, 5 to 10 days after the onset of fever, and follow-up studies were performed 1 to 2 months later. Patients in whom coronary aneurysms developed were more likely to have pericardial effusion (p = 0.0006) or mitral regurgitation (MR) (p = 0.014) at initial echocardiographic study than those without aneurysms. Presence of either mitral regurgitation (MR) or pericardial effusion had a positive predictive value of 0.84 for aneurysm development. Twenty-three percent of patients had MR, and it was associated with mild LV dilatation (35 +/- 3 vs 32 +/- 5 mm, p less than 0.05). Insufficiency of other valves was rare. Thus, MR and pericardial effusion on acute phase echocardiographic examination may predict development of coronary aneurysms in Kawasaki disease. Mild MR occurs frequently in acute Kawasaki disease and is associated with mild LV dilation.

Retrograde dual atrioventricular nodal pathways.

Thirty-one (3.5 percent) of 887 studied patients had retrograde dual atrioventricular (A-V) nodal pathways, as manifested by discontinuous retrograde A-V nodal conduction curves (29 patients) or by two sets of ventriculoatrial (V-A) conduction intervals at the same cycle length (2 patients). All patients had A-V nodal reentrant ventricular echoes of the unusual variety induced with ventricular stimulation (25 patients had single, 2 patients had double and 4 patients had more than three ventricular echoes). The weak link of the reentrant circuit was always the retrograde slow pathway. Eleven of the 31 patients also had anterograde dual A-V nodal pathways (bidirectional dual pathways). Eight patients (26 percent) had spontaneous as well as inducible A-V nodal reentrant paroxysmal supraventricular tachycardia (of the unusual type in three and the usual type in five). In addition, three patients (10 percent) had only inducible supraventricular tachycardia (two of the unusual and one of the usual type). Retrograde dual A-V nodal pathways are uncommon. They are associated with the finding of at least single A-V nodal reentrant ventricular echoes (all patients), anterograde dual pathways (one third of patients) and A-V nodal reentrant paroxysmal supraventricular tachycardia of the usual and unusual variety (one third of patients).

Complex ventricular ectopic activity in patients less than 20 years of age with or without syncope, and the role of ventricular extrastimulus testing.

To assess the potential for ventricular tachycardia (VT), ventricular extrastimulus testing was performed in 33 young patients with complex ventricular ectopic activity defined as multiform ventricular premature complexes (VPCs), couplets or nonsustained VT, or a combination, found during electrocardiographic monitoring. There were 21 male and 12 female patients with a mean age of 11 years (range 1 to 18). Patients were divided into 2 groups based on the presence (14 patients) or absence (19 patients) of syncope. Patients with syncope had ostensibly normal hearts (9 patients) or miscellaneous heart disease (5 patients). Patients without syncope had ostensibly normal hearts (8 patients) or miscellaneous heart disease (11 patients). Ventricular stimulation protocol consisted of burst pacing and 1 to 4 programmed extrastimuli decreasing to refractoriness at 3 drive-train cycle lengths, and at 2 pacing sites (right ventricular apex and outflow tract) during the drug-free baseline state and isoproterenol infusion. No patient had VT induced with 1 or 2 extrastimuli. VT was induced in 13 of 14 patients (93%) with syncope, and in 9 of 19 patients (47%) without syncope (p less than 0.05). Using a 3-extrastimuli protocol, 8 of 14 patients (57%) with and 3 of 19 patients (16%) without syncope had VT induced (p less than 0.05). These findings suggest that VT may be the cause of syncope in young patients with complex ventricular ectopic activity.

Procainamide-induced polymorphous ventricular tachycardia.

Seven cases of procainamide-induced polymorphous ventricular tachycardia are presented. In four patients, polymorphous ventricular tachycardia appeared after intravenous administration of 200 to 400 mg of procainamide for the treatment of sustained ventricular tachycardia. In the remaining three patients, procainamide was administered orally for treatment of chronic premature ventricular contractions or atrial flutter. These patients had Q-T prolongation and recurrent syncope due to polymorphous ventricular tachycardia. In four patients, the arrhythmia was rapidly diagnosed and treated with disappearance of further episodes of the arrhythmia. In two patients, the arrhythmia degenerated into irreversible ventricular fibrillation and both patients died. In the seventh patient, a permanent ventricular pacemaker was inserted and, despite continuation of procainamide therapy, polymorphous ventricular tachycardia did not reoccur. These seven cases demonstrate that procainamide can produce an acquired prolonged Q-T syndrome with polymorphous ventricular tachycardia.

Preparation of the left ventricle for anatomical correction in patients with simple transposition of the great arteries. Surgical guidelines.

Pulmonary artery banding in combination with an aortopulmonary shunt was performed on 16 patients with simple transposition of the great arteries to prepare the left ventricle for anatomical correction. Three groups were identified after operation: Group I (four patients) had increased pulmonary blood flow and tight pulmonary artery banding; Group II (four patients) had increased pulmonary blood flow and moderate pulmonary artery banding; Group III (eight patients) had normal pulmonary blood flow and moderate pulmonary artery banding. Postoperative low cardiac output was present in all patients in Group I, whereas mild heart failure was present in two patients in Group II and in two in Group III. There was one hospital death (6%). The follow-up period was 125 patient-months. Left ventricular systolic pressure rose from 63 +/- 11 torr before the operation to 101 +/- 35 torr after the procedure in Group I (p less than 0.05), from 59 +/- 10 to 93 +/- 33 torr in Group II (p less than 0.05), and from 55 +/- 10 to 84 +/- 16 torr in Group III (p less than 0.005). The increase in left ventricular muscle mass was from 44 +/- 2 gm/m2 preoperatively to 108 +/- 12 gm/m2 after operation in Group I (p less than 0.01), from 43 +/- 3 to 93 +/- 8 gm/m2 in Group II (p less than 0.02), and from 46 +/- 3 to 55 +/- 14 gm/m2 in Group III (p = no statistically significant difference). The postoperative change in left ventricular end-diastolic volume was from 100% +/- 17% to 133% +/- 23% of normal in Groups I and II (p less than 0.05) and from 123% +/- 29% to 107% +/- 36% of normal in Group III (p = no statistically significant difference). In preparing the left ventricle for anatomical correction, avoidance of severe pulmonary artery banding decreases the incidence of postoperative myocardial dysfunction, a moderate degree of volume overload and pulmonary artery banding provides the most effective stimulus for ventricular growth, and a small to moderate atrial septal defect is advantageous because it ensures the volume preload necessary for the development of the left ventricle.

Transposition of the great arteries with intact ventricular septum. Arterial switch in the first month of life.

Twenty-three infants with simple transposition of the great arteries and intact ventricular septum were operated on from October 1983 to October 1986. The age at operation in 22 infants ranged from 2 to 21 days and in one was 35 days (mean 9.82 +/- 6.86 days). The infants were evaluated with cardiac catheterization at 1 to 27 days of age. Twenty-two infants had balloon atrial septostomy, and 22 received prostaglandin E1 infusion. The left ventricular diastolic wall thickness, assessed by M-mode echocardiograms, varied between 2.8 and 4 mm. There were two hospital deaths in this group of 23 infants (mortality 8.6%), and there were no late deaths. All surviving patients are doing well clinically. One patient had asymptomatic nonsustained ventricular tachycardia necessitating phenytoin. Postoperative echocardiographic assessment performed on 15 patients at 0.93 +/- 0.61 years of age and cardiac catheterization and angiographic studies on seven patients at 1.07 +/- 0.13 years after operation revealed excellent ventricular performance, good semilunar valve function, and mild gradient at the right ventricular outflow with a mean right ventricular pressure of 37.4 +/- 4.1 torr.

Arterial switch in simple and complex transposition of the great arteries.

Arterial switch for repair of transposition of the great arteries was performed on 53 patients since October 1983. These patients were divided into three groups: group I, 25 infants with an intact ventricular septum who had primary repair in the first month of life (2 to 34 days of age, mean 9.7 +/- 6.6); group II, 13 patients with an intact ventricular septum who had anatomic repair after a preliminary procedure (pulmonary artery banding in 13, shunt in 10, atrial septectomy in 1); and group III, 15 infants with transposition of the great arteries and ventricular septal defect. In group III, six patients had Taussig-Bing abnormality, nine had previous pulmonary artery banding, three had coarctation of the aorta repaired earlier in life, and four were less than 2 weeks old. Overall early mortality was 9.4% (5/53: group I 8%, group II 7.6%, group III 13.3%). Two late deaths occurred in group II 10 and 12 weeks postoperatively after infection and high fever. A third late death 18 weeks postoperatively was due to aspiration in an infant with Goldenhar's syndrome. Mortality and morbidity decreased significantly after an initial learning period (no deaths from July 1985 to March 1987 overall, and none in the last 15 infants operated on in group I). The surviving 45 patients are doing well. All have normal sinus rhythm. Two had transient asymptomatic arrhythmias. Left and right ventricular function assessed by echocardiogram and postoperative cardiac catheterization were within normal ranges in all but two patients, one with pulmonary artery stenosis and one (Taussig-Bing abnormality with two large ventricular septal defects) with severe pulmonary vascular disease (9.6 units) observed before anatomic repair. The right ventricular pressure at catheterization ranged from 27 to 42 mm Hg in 12 patients and was 55 mm Hg in two. There was no aortic stenosis. Aortic insufficiency was trivial in three patients and mild in one. We conclude that excellent results can be obtained with arterial switch for transposition of the great arteries with or without ventricular septal defect, especially in neonates.

Experience with St. Jude Medical valve prosthesis in children. A word of caution regarding right-sided placement.

Thirty-six children aged 6 months to 18 years, underwent insertion of 37 St. Jude Medical cardiac prostheses. In 20, the valve was placed in the aortic or mitral position, and in 16 in the pulmonary or tricuspid position. There was one (2.8%) hospital death. All patients received maintenance doses of salicylates and dipyridamole after the operation. Follow-up data are available for all patients for 12 to 24 postoperative months. There was no incidence of valve dysfunction or thromboembolic complication in any of the 20 patients with valves in the systemic (left) side of the circulation, and all manifested improvement in their functional class. In contrast, six (37%) of the 16 patients with valves in the pulmonary (right) side of the circulation developed dysfunction of the prosthesis 1 to 6 months after insertion. Prosthesis failure was associated with fibrous tissue growing into the struts, leading to leaflet immobilization. At 2 years, the actuarial functional life was 100% for mitral and aortic valves and 70% for pulmonary and tricuspid valves. The data illustrate the excellent hemodynamic function of the St. Jude Medical valve in children. The absence of thromboembolic complications warrant continued implantation of the prosthesis in the left side without warfarin anticoagulation therapy, but the high incidence of valve dysfunction in the pulmonary position does not justify its continued use in the right side.

An alternative approach to the surgical management of physiologically corrected transposition with ventricular septal defect and pulmonary stenosis or atresia.

A modified approach to the surgical management of corrected transposition of the great vessels with ventricular septal defect and pulmonary stenosis or atresia was used successfully in two patients. The procedure consisted of performing a venous switch operation, directing the blood flow from the morphologically left ventricle (right-sided chamber) into the aorta through the ventricular septal defect and inserting a valved conduit between the left-sided morphologically right ventricle and the pulmonary artery. This approach has several advantages when compared with the traditional surgical management, which consists of closure of the ventricular septal defect and a left ventricular (right-sided chamber) to pulmonary artery conduit. It uses the morphologically left ventricle as the systemic pumping chamber, thereby minimizing long-term ventricular failure. It allows closure of the defect from the right ventricular side of the septum, thus decreasing the prevalence of complete atrioventricular block. It also avoids use of the tricuspid valve as the systemic atrioventricular valve and therefore decreases the chance of postoperative valve regurgitation.

The Damus-Stansel-Kaye procedure. Should the aortic valve or subaortic valve region be closed?

Two patients (one with transposition of the great arteries and another with Taussig-Bing anomaly) underwent the Damus-Stansel-Kaye procedure (Group I). Significant aortic valve insufficiency developed postoperatively in both patients. In contrast, seven patients with a univentricular heart and subaortic stenosis from a variety of reasons underwent creation of an aortopulmonary window (Group II), a procedure very similar to the proximal main pulmonary artery-aortic root anastomosis of the Damus-Stansel-Kaye procedure. Aortic valve insufficiency had not developed after up to 7 years of follow-up in this group (average 43 months). Postoperative angiograms suggest that aortic valve incompetence in Group I may have been caused by prolapse of the aortic valve. The valvular structures are subjected to high systolic pressures and face a dilated, low-pressure right ventricle. Aortic root distortion may have contributed, as well. In Group II patients, the aortic valve structures face a small, thick-walled chamber. The orientation of the aortic valve vis-a-vis the right ventricle changed postoperatively in Group I but not in Group II patients. Our experience suggests that the aortic valve or subaortic valve region should be closed at the initial repair in patients with low pulmonary vascular resistance who are undergoing the Damus-Stansel-Kaye procedure, to minimize the need for reoperation for aortic valve insufficiency.

Effects of elevated coronary sinus pressure on left ventricular function after the Fontan operation. An experimental and clinical correlation.

An experimental model was devised to evaluate the effects of elevated coronary sinus pressure on left ventricular performance. Thirteen mongrel dogs were used. The coronary sinus was cannulated and its entire blood flow diverted into a reservoir. The pressure in the coronary sinus was increased from 5 to 25 torr by elevating the drainage reservoir in a stepwise fashion. Cardiac index, coronary arteriovenous difference, rate of rise of left ventricular pressure, left ventricular systolic time intervals, and coronary blood flow were measured. When the coronary sinus pressure reached 15 torr, there was a significant decrease in cardiac index (3.60 +/- 0.5 to 2.70 +/- 0.6 L/min/m2, p less than 0.001), coronary blood flow (13.7 +/- 3.1 to 7.0 +/- 2.1 ml/min, p less than 0.001), rate of rise of left ventricular pressure (1,567 +/- 275 to 1,331 +/- 314, p less than 0.05), and an increase in coronary arteriovenous difference (62.8% +/- 9.3% to 70.5% +/- 5.4% saturation, p less than 0.03). These experimental results were correlated with postoperative catheterization findings in 24 patients with the Fontan procedure. Patients with a mean right atrial pressure less than 15 torr had a left ventricular ejection fraction of 93% +/- 6% of predicted, whereas patients with a right atrial pressure of 15 torr or more had a left ventricular ejection fraction of 75% +/- 13% of predicted (p less than 0.001). These experimental and clinical data strongly suggest that elevated coronary sinus pressure has deleterious effects on ventricular function after the Fontan procedure. Modifications of the procedure, such as using the rudimentary right ventricle when feasible or diverting coronary sinus flow to the pulmonary venous atrium, might decrease coronary sinus hypertension and improve long-term results.

Biventricular repair of hypoplastic right ventricle assisted by pulsatile bidirectional cavopulmonary anastomosis.

The right ventricle in patients with severe outflow obstruction or atresia and a small tricuspid valve often remains too hypoplastic even after optimal palliation to tolerate biventricular repair with closure of the atrial septal defect. In these patients, nonpulsatile cavopulmonary (Glenn) anastomosis has traditionally facilitated biventricular repair. In 1989, Billingsley and associates reported the addition of a bidirectional cavopulmonary anastomosis to the definitive biventricular repair in patients with hypoplastic right ventricle, pulmonary atresia, and intact ventricular septum. The atrial septal defect was left open with an adjustable snare for later closure. We report five patients with hypoplastic right ventricle (mean diastolic volume 48.4%, mean stroke volume 40.2% of predicted value) who had the atrial septal defect closed at the time of the biventricular repair. Four patients, who had the bidirectional cavopulmonary anastomosis supplementing the biventricular repair, had no evidence of excessive right atrial or superior vena cava hypertension postoperatively. One patient, who had atypical tetralogy of Fallot with tricuspid stenosis, developed recurrent pericardial tamponade and marked hepatomegaly following conventional tetralogy repair with closure of the atrial septal defect. These complications were controlled with the addition of bidirectional cavopulmonary anastomosis 2 months later. Postoperative hemodynamic or Doppler studies in these patients revealed pulsatile flow in the entire pulmonary artery system, including the artery distal to the Glenn anastomosis. This modification of biventricular repair allows primary closure of the atrial septal defect and provides pulsatile arterial flow in the entire pulmonary artery, even when the right ventricle is significantly hypoplastic.

Dobutamine stress echocardiography: experience in pediatric heart transplant recipients.

BACKGROUND: Transplant coronary arteriopathy causes late death and is difficult to detect noninvasively. Dobutamine stress echocardiography is being used for risk stratification in adult recipients at some transplant centers, thus we investigated its role in a pediatric population. METHODS: We performed 46 stress echo studies (mean age = 11.8 years; mean years post transplantation = 4.3). An atropine/dobutamine protocol (5-40 mcg/kg/min) was used to attain a predicted target heart rate. Serial echocardiographic images were acquired at baseline and at each increment of dobutamine and recovery, and were digitized online. Data were correlated with endomyocardial biopsy (n = 23), coronary angiography (n = 26) or autopsy (n = 6). All studies were well tolerated. RESULTS: Target heart rate was achieved in 41/46 (89%) studies. The mean heart rate significantly increased from 95 to 169 beats/min and mean systolic blood pressure from 123 to 153 mm Hg (p<.05). The mean peak pressure-rate product was 23,041 beats-mm Hg/min. Coronary arteriopathy was confirmed in 5 patients by angiography (n = 3) explanted heart (n = 1) or autopsy (n = 4). In this group, abnormalities included a new reversible wall motion abnormality (n = 2), left ventricular cavity dilation with stress (n = 3), ischemia (n = 2), increased mitral insufficiency (n = 1) and marked diastolic dysfunction (n = 1). A positive study predicted death or graft failure (p< .0005). CONCLUSIONS: Echocardiographic abnormalities during stress correlated with coronary arteriopathy in this small cohort of patients; however, larger multi-center studies are warranted to assess the utility of dobutamine stress echocardiography for risk stratification for coronary disease in pediatric transplant recipients.

Myocardial acoustics in pediatric allograft rejection.

BACKGROUND: Ultrasonographic tissue characterization is the assessment of physical properties of biologic tissue on the basis of quantitative analysis of its acoustic characteristics. Abnormalities in microscopic structure that occur with cardiac allograft rejection may result in characteristic alterations in myocardial acoustics. Ultrasonographic tissue characterization may allow noninvasive detection of rejection. METHODS: Findings in 22 pediatric heart transplant patients undergoing routine surveillance for rejection by endomyocardial biopsy were prospectively evaluated. Off-line ultrasonographic tissue characterization analysis was done on transthoracic echocardiograms obtained at each biopsy. Within patients, tissue characterization texture measures derived from the ultrasonographic image data were compared with histologic findings. Univariate multiple regression analysis was used to identify texture measures associated with acute allograft rejection in a subgroup (n = 8) with at least one biopsy-proven episode of moderate rejection. RESULTS: Measures of homogeneity (co-occurrence matrix correlation and heterogeneity (run-length nonuniformity) decreased with moderate rejection (p < 0.03). Homogeneity measures decreased if the patient had a previous episode of rejection. Several measures of heterogeneity (gray level difference and run-length statistics) were affected by the presence of edema. Run-length nonuniformity was the only measure that differentiated moderate rejection from edema. Discriminant analysis on all 22 patients correctly identified 96% of first rejection episodes (sensitivity 80%, specificity 64%), 93% of moderate and severe rejection episodes (sensitivity 71%; specificity 62%), and 69% of all rejection episodes (sensitivity 51%, specificity 91%). CONCLUSIONS: Histologic changes associated with moderate and severe pediatric allograft rejection as reflected by characteristic alterations in myocardial acoustics can be assessed with ultrasonographic tissue characterization. Histologic changes associated with transplantation itself (resolution of rejection and edema) also affect myocardial acoustics and must be taken into account in rejection surveillance.

Does banding the pulmonary artery affect pulmonary valve function after the Damus-Kaye-Stansel operation?

BACKGROUND: The Damus-Kaye-Stansel (DKS) operation can be an effective palliation in patients who have single-ventricle physiology and systemic outflow obstruction. Pulmonary artery banding (PAB) may be used as a preliminary procedure in these patients to limit overperfusion of the pulmonary circulation. In some series, the DKS operation has been associated with pulmonary insufficiency (PI). We retrospectively analyzed medical records of our patients who had PAB and later DKS to determine the incidence of PI in these patients. METHODS: Between 1982 and 1996, 15 patients underwent PAB before DKS. Median age at PAB placement was 7 days and median duration of PAB was 7 months. Echocardiograms obtained before PAB, before DKS, and at the most recent post-DKS follow-up were reviewed. RESULTS: Follow-up ranged from 1 to 15 years (mean follow-up, 7.5 years). One patient had trivial PI before PAB, which progressed to moderate PI at the last follow-up. Only 1 other patient had mild PI, but only at the last follow-up after DKS. CONCLUSIONS: These findings suggest that prior PAB does not appear to cause significant PI in patients slated for DKS, and the incidence of significant PI after the DKS operation is relatively low.

Supraarterial decompression myotomy for myocardial bridging in a child.

A 10-year-old boy presented with a history of exertional chest pain. An electrocardiogram demonstrated an inferior apical myocardial infarction. Cardiac catheterization revealed myocardial bridging of the left anterior descending coronary artery with evidence of intramyocardial obstruction during systole. The patient underwent successful treatment with supraarterial decompression myotomy and remains symptom free at 1 year.