Paolo Guccione

Anomalous coronary artery origin from the pulmonary artery: correlation between surgical timing and left ventricular function recovery

BACKGROUND This study investigates the correlation between surgical timing and 15-year longitudinal left ventricular and mitral valve function, after repair of anomalous coronary artery origin from the pulmonary artery. METHODS Between 1987 and 2002, 31 patients (median age, 7.1 months) underwent repair for anomalous origin of the left (n = 28), right (n = 2), or both (n = 1) coronary arteries from the pulmonary artery. Repair was accomplished by subclavian interposition in 5 patients, intrapulmonary tunnel in 12, and direct aortic reimplantation in 14. Primary mitral valve repair was never associated with coronary revascularization. Total follow-up was 186.4 patient-years (mean, 77.2 months). RESULTS Fifteen-year actuarial survival was 92.9% +/- 4.9% for coronary transfer, 40.0% +/- 21.9% for subclavian interposition, and 89.9% +/- 7.5% for intrapulmonary tunnel (p = 0.019). Five patients required further intervention for supravalvular pulmonary stenosis (n = 3), baffle leak (n = 1), and mitral valve replacement (n = 1). Coronary transfer allowed best freedom from long-term reoperation (92.3% +/- 7.4%). Left ventricular shortening fraction increased from 17.3% +/- 6.3% before operation to 34.1% +/- 4.6% at last follow-up (p < 0.01). Regression analysis demonstrated a linear relationship between age at repair and shortening fraction recovery (r(2) = 0.573, p < 0.01). Patients younger than 6 months of age showed worse preoperative shortening fraction (15.9% +/- 5.2%) and best longitudinal shortening fraction recovery (36.4% +/- 5.1%; p < 0.001). Major improvement in mitral valve function was observed within 1 year from surgery in 90.4% of survivors. CONCLUSIONS Repair of anomalous coronary artery origin from the pulmonary artery in younger symptomatic infants offers the best potential for recovery of left ventricular function, despite a worse initial presentation. Coronary transfer is associated with superior long-term survival and freedom from reoperation. Most patients with patent two-coronary repair will recover normal mitral valve function; therefore, simultaneous mitral valve surgery seems unwarranted.

Permanent overdrive atrial pacing in the chronic management of recurrent postoperative atrial reentrant tachycardia in patients with complex congenital heart disease

This study investigated the value of permanent atrial pacing as an adjunct to the current therapy in the chronic management of recurrent postoperative atrial reentrant tachycardia in patients with complex congenital heart disease. We studied the postpacing clinical course in 18 patients with recurrent atrial reentrant tachycardias unresponsive to conventional therapy who had an implanted atrial pacemaker. The pacemaker was programmed at a lower pacing rate 20% faster than the spontaneous mean daily rate previously determined with 24‐hour Holter monitoring. Serial Holter recordings and pacemaker programming sessions were subsequently performed trying to mantain a paced atrial rhythm overdriving the spontaneous rhythm as long as possible. Twenty‐four hour Holter monitoring documented a prevalent (> 80%) paced rhythm during the daily hours in all patients during the follow‐up; all patients, however, required at least once a variation In programmed mode and pacing rate. Antiarrhythmic medications were discontinued after 6 months if the patient remained arrhythmia free while on pacing. Recurrences of atrial reentrant tachycardia occurred in five patients (29%) during the initial 6 months interval after the pacemaker implantation, while late recurrences occurred in only two patients (11 %). One patient died suddenly 10 months after the pacemaker implant. At the end of the follow‐up, 15 patients (83%) were arrhythmia‐free and only 2 of them were still on antiarrhythmic drugs. We conclude that permanent atrial overdrive pacing can be an important tool in the management of patients with atrial reentrant tachycardia following repair of congenital heart disease.

Treatment of pulmonary artery stenosis after arterial switch operation: Stent implantation vs. balloon angioplasty

The development of pulmonary artery stenosis is a potential complication during the mid‐ to long‐term follow‐up after arterial switch operation (ASO) for transposition of the great arteries. Surgical results have been disappointing and conventional balloon dilation yields a fairly important incidence of failures and recurrences. We evaluated our results with implantation of balloon‐expandable stents in 5 out of 13 patients with a previously attempted unsuccessful conventional balloon dilation of pulmonary artery branch stenosis after ASO. In two more cases, stents were used as a primary procedure. Balloon angioplasty achieved a 15% increase in mean diameter of the stenosis vs. 124% with the use of stents (P < 0.01), a 10% decrease of the pressure gradient across the stenosis vs. 71% of stents (P < 0.01), and a 10% drop in RV/aorta pressure ratio vs. 43% of stents (P < 0.01). Compared to conventional balloon angioplasty in our series, stents were more effective in the treatment of patients with peripheral pulmonary artery stenosis after ASO. Balloon dilation should be considered in selected cases unsuitable for treatment with endovascular stents. Cathet. Cardiovasc. Intervent. 50:207–211, 2000.

Oral propafenone therapy for children with arrhythmias: Efficacy and adverse effects in midterm follow-up

The use of oral propafenone was assessed in 57 children. Mean age was 4.8 +/- 5.2 years (range 1 day to 17 years). Twenty-three patients were less than 1 year of age (40%) and 10 were less than 1 month of age (18%). Arrhythmias included supraventricular tachycardia in 32 patients (57%), atrial flutter in six (10%), and ventricular tachycardia in 19 (33%). Cardiac diagnoses included: an otherwise normal heart in 30 (53%); unoperated congenital heart defect in 11 (19%); cardiomyopathy in nine (16%); and an operated congenital heart defect in seven (12%). Mean dose of propafenone was 13.1 mg/kg/day (range 8 to 15). Success (assessed by relief of symptoms and serial 24-hour ECGs) was achieved in 16 of 32 patients with supraventricular tachycardia (50%), three of six with atrial flutter (50%), and 8 of 19 with ventricular tachycardia (42%). Drug efficacy in patients with and without organic heart disease was 30% (8 of 27) and 63% (19 of 30), respectively (p less than 0.05). Mean duration of therapy in patients in whom the drug was effective was 22.9 +/- 13.2 months (range 6 to 60). Growth was unimpaired in all patients. A neonate with nonsustained monomorphic ventricular tachycardia had sustained ventricular tachycardia during the second day of propafenone therapy at a dose of 13 mg/kg/day. Sustained ventricular tachycardia disappeared when the drug was discontinued. Another patient had an asymptomatic and transient increase in the glutamic pyruvic transaminase level. No adverse hemodynamic effects were observed. In conclusion, propafenone is an effective antiarrhythmic drug in children with normal hearts; it is less effective in patients with heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy and safety of ventricular rate responsive pacing in children with complete atrioventricular block

Single chamber rate responsive pacing offers many potential advantages over the more complex dual chamber atrial tracking pacing mode in children, and the preservation of atrioventricular synchrony could be unnecessary in selected groups of pediatric patients. Twenty‐two pediatric patients (age range 9 months to 12 years; mean 6.5 years) had implantation of ventricular rate responsive (VVIR) pacemakers over a 2‐year period. All patients had chronic third‐degree atrioventricular block, and a normal ventricular function at rest. During the follow‐up each patient underwent a 24‐hour Holter monitoring, and ten performed a graded treadmill test in both ventricular fixed rate (VVI) and rate responsive (VVIR) pacing mode. Paced ventricular rates were found to be normal for age in all 22 patients; maximum rate did not reach the higher programmed rate during daily activities in any patient. Comparing the mean paced ventricular rate to the mean rates of blocked P waves, six patients showed a difference of more than 20 beats/min, which induced the pacemaker parameters to be reprogrammed. In all patients a significant correlation was found between variations of paced ventricular rate and variations of spontaneous blocked atrial rhythm (P < 0.05); this correlation persisted in the subsequent Holter controls in the ten patients with longer follow‐up. Exercise tolerance resulted normal in the ten patients who performed a treadmill test either in VVIR or VVI mode, with increased maximal heart rates and maximal systolic blood pressure in VVIR mode (P < 0.0013). Rate responsive ventricular pacemakers seem to adequately respond to the physiological needs of daily life of this selected group of children requiring permanent pacing.

Indication for systemic-pulmonary artery shunts guided by two-dimensional and Doppler echocardiography: criteria for patient selection.

From June, 1983, to February, 1987, 91 patients with pulmonary outflow tract obstruction underwent a systemic-to-pulmonary artery shunt without an invasive study. The surgical indication was based on two-dimensional (2-D) and Doppler echocardiography only. In 82 patients (90.1%), 2-D and Doppler echocardiography allowed correct assessment of the intracardiac anatomy and of the morphology of the pulmonary arteries, pulmonary veins, and aortic arch. The aortic arch anatomy was misdiagnosed in 6 patients (6.6%) who underwent a modified instead of a classic Blalock-Taussig shunt. In 3 patients (3.3%), the indication for the systemic-pulmonary artery shunt was inappropriate; in 1, operative death resulted from the incomplete diagnosis. After the preselection of patients based on knowledge of the anatomical patterns, a systemic-pulmonary artery shunt may be performed without cardiac catheterization if these rules for definitive patient selection are followed: (1) accurate clinical assessment to identify the patients with restricted pulmonary blood flow; (2) precise intracardiac diagnosis by 2-D and Doppler echocardiography; and (3) definitive 2-D echocardiographic visualization of the pulmonary venous connection and the confluence of the pulmonary arteries.

Complete transposition of the great arteries: Visualization of left and right outflow tract obstruction by oblique subcostal two-dimensional echocardiography

Subcostal oblique 2-dimensional echocardiography was performed in 64 infants younger than 2 years with complete transposition of the great arteries (TGA) (situs solitus, concordant atrioventricular and discordant ventriculoarterial connections). All patients examined before cardiac catheterization had a correct diagnosis by 2-dimensional echocardiography using the subcostal oblique views. Twelve patients had associated left ventricular (LV) outflow tract obstruction and 7 had right ventricular (RV) outflow obstruction. The standard parasternal views failed to diagnose obstruction in 1 patients with LV outflow obstruction and 5 with RV outflow obstruction; the subcostal left oblique cut and long axis of the left ventricle visualized all left-sided obstructions, and right-sided obstructions were correctly displayed in 5 of 7 cases using a combination of left oblique and right oblique cuts. Two-dimensional echocardiographic subcostal oblique views allow an excellent definition of the morphologic characteristics of RV and LV outflow tracts in patients with TGA and improve the diagnosis of the outflow obstruction in these malformations.

Significance of high voltage QRS anterior forces in young asymptomatic adults. Evaluation by wide-angle two-dimensional echocardiography

Thirteen asymptomatic adults less than 40 years old who showed tall right precordial R waves on the ECG were examined by VCG, M-mode and two-dimensional echocardiography (2D Echo). Common causes of QRS anterior displacement, such as right ventricular enlargement or right bundle branch block, were excluded in each subject. Although each subject was normal at physical examination, 2D Echo revealed areas of left ventricular hypertrophy in eight of these 13 subjects. Four had a prevailing hypertrophy of the basal portion of the interventricular septum, three had an isolated apical hypertrophy, and one had a diffuse concentric left ventricular hypertrophy. Results were normal in five cases. 2D Echo classification was confirmed by heart catheterization findings, when available. The subjects with asymmetric septal hypertrophy showed low-voltage QRS leftward forces on the ECG and VCG. ECGs and VCGs were not useful in differentiating the subjects with atypically distributed left ventricular hypertrophy from the normals: high-voltage QRS leftward forces and T wave abnormalities were evident in some subjects of both groups. Tall right precordial R waves may constitute a marker of hypertrophic cardiomyopathy in asymptomatic young adults. 2D Echo is useful to exactly classify these subjects.

Ductus Arteriosus in Pulmonary Atresia with and Without Ventricular Septal Defect: Anatomic and Functional Differences

The pulmonary circulation is dependent on the ductus arteriosus in all patients with pulmonary atresia and intact ventricular septum and in some with pulmonary atresia and ventricular septal defect (tetralogy of Fallot type). To assess the time of ductal closure in these two patient categories, we compared the ages at first operation in 58 patients with pulmonary atresia and intact ventricular septum and 32 with pulmonary atresia and septal defect. The age distribution differed significantly between the groups. Whereas 90% of the children with intact ventricular septum required surgery in the first week of life, 50% of those with ventricular septal defect underwent surgery after the first month and 25% after the third month. The previously described and now confirmed anatomic differences of ductus arteriosus or different levels of endogenous prostaglandins may explain persistent patency of the ductus in pulmonary atresia with ventricular septal defect. The phenomenon may have important clinical implications regarding the timing and choice of surgical procedure.

Erythrocytosis and severe asphyxia: Two different causes of neonatal myocardial infarction

Neonatal acute myocardial infarction is a rare event that carries a high mortality rate. We describe the cases of two newborns who survived acute myocardial infarction and discuss the management. The first neonate was born with severe asphyxia and left ventricular myocardial infarction with ventricular tachycardia. In this patient, systemic flow was maintained by right-to-left shunting through the patent ductus arteriosus. The second neonate presented with a haematocrit of 80% and an inferolateral myocardial infarction. Intensive treatment of low cardiac output syndrome led to survival of both high-risk neonates. In the follow-up, at 48 and 4 months, respectively, ventricular function recovered in both patients.