David A. Ott

Treatment of atrial automatic tachycardia by ablation procedures

Sixteen cases of atrial focus tachycardia are described clinically, electrophysiologically and hemodynamically. In each case multiple attempts at drug treatment (average 2.5 drugs) had failed. After delineation of the electrophysiologic mechanism, the patients were treated by surgical removal or cryoablation or catheter electroablation of the focus. In two of four patients catheter ablation was successful and without complication. Surgical treatment was successful in 13 of 14 patients. Left ventricular function, which had been abnormal in 10 patients, normalized in all but 1 patient whose echocardiographic shortening fraction improved from 10 to 27%. There have been no recurrences in a follow-up period of 6 months to 5 years (mean 2.2 years). It is recommended that any atrial automatic focus tachycardia that produces hemodynamic compromise undergo definitive treatment. Patients with chronic tachycardia rates of more than 140 beats/min should be followed up closely.

Junctional automatic ectopic tachycardia: New proposed treatment by transcatheter His bundle ablation☆

Three infants with junctional automatic ectopic tachycardia (JET) were seen over an 8-month period. Each had decreased left ventricular function. Two were treated with amiodarone, which together with propranolol reduced the tachycardia rate 10 to 40 bpm, but did not result in sinus rhythm. One patient died suddenly at home, as had 50% of our patients with JET treated with conventional medication. Two patients were treated by transcatheter ablation of the bundle of His and implantation of an atrial synchronous pacemaker. Neither has had subsequent tachycardia or required drugs. One patient resumed sinus rhythm and does not use his pacemaker. The other patient has complete AV block and continues to use her pacemaker. This aggressive approach to this lethal dysrhythmia offers hope for prevention of the former bad prognosis.

Influence of age on the effect of bidirectional cavopulmonary anastomosis on left ventricular volume, mass and ejection fraction

OBJECTIVESnWe sought to identify age-related differences in the ventricular response of patients after bidirectional cavopulmonary anastomosis (CPA) and to compare changes in the ventricular response among children < 3 years of age who underwent CPA with that of age-matched control subjects who had a systemic to pulmonary artery shunt alone.nnnBACKGROUNDnPre-Fontan CPA has been advocated over a systemic to pulmonary artery shunt alone in patients with a single ventricle to facilitate ventricular volume unloading and minimize risk of the Fontan operation.nnnMETHODSnOur study evaluated 23 patients who initially received a systemic to pulmonary artery shunt as an initial procedure before subsequent Fontan palliation. In eight of these patients (group I), bidirectional CPA was performed before age 3 years, and in four (group II), it was performed after age 10 years. The remaining 11 patients (group III, age and weight control group for group I) were maintained with their initial shunt until they underwent Fontan palliation. Serial echocardiographic analysis was used retrospectively to evaluate left ventricular volume and mass and systolic pump function (ejection fraction) before and after bidirectional CPA.nnnRESULTSnThrough 10 months of follow-up, group I patients showed significant decreases in indexed end-diastolic volume both after CPA (120 ml/m1.5 body surface area vs. 78 ml/m1.5, p = 0.001) and in comparison with values in patients in group II and III, who showed no changes in end-diastolic volume (p < 0.001). Indexed ventricular mass decreased moderately after bidirectional CPA in group I (from 228 g/m1.5 body surface area to 148 g/m1.5) but remained unchanged in groups II and III. The differences in trends between groups I and III were significant (p = 0.03). Ejection fraction decreased significantly in group II versus group I patients (0.48 to 0.27 vs. 0.51 to 0.52, p < 0.05) after CPA. Oxygen saturation measurements before and after bidirectional CPA revealed a significant increase in group I (73% to 86%, p < 0.001) and a decrease in group II (82% to 73%, p < 0.01).nnnCONCLUSIONSnBidirectional CPA facilitates ventricular volume unloading and promotes regression of left ventricular mass in younger children (< 3 years) in preparation for a Fontan operation. In contrast, bidirectional CPA is of questionable value in older children as a staging procedure for Fontan palliation.

Hypoplastic left heart syndrome: Is echocardiography accurate enough to guide surgical palliation?

Two-dimensional echocardiography can diagnose hypoplastic left heart syndrome. However, with the advent of the possibility of palliative open heart surgery, complete anatomic diagnosis is necessary. The anatomic findings of 15 neonates with hypoplastic left heart syndrome (age 1 to 10 days, mean 4.1) who had two-dimensional Doppler echocardiographic studies were compared with the results obtained by angiography (6 cases), surgery (11 cases) and autopsy (8 cases). Complete two-dimensional echocardiographic examination of the aortic arch, pulmonary and systemic venous return, atrial septum, ductus arteriosus and proximal coronary arteries was possible in all 15 neonates and correctly diagnosed hypoplastic left heart syndrome in each. Anatomic two-dimensional echocardiographic assessment was accurate in 13 (86%) of the 15 neonates and there were no false positive results. Undiagnosed associated abnormalities were hypoplasia of a left pulmonary artery in one patient and left superior vena cava in another. Accurate quantitation of the size of the tricuspid valve anulus, ascending aorta, pulmonary anulus and right and left pulmonary arteries was possible. Doppler examination was performed in seven patients and confirmed retrograde aortic arch flow and right to left systolic shunting in the patent ductus arteriosus. In selected neonates, surgical palliation can be attempted without angiography.

Management of postoperative chylopericardium in childhood.

1. Josephson ME, Kastor JA. Paroxysmal supraventricular tachycardia. Is the atrium a necessary link? Circulation 1976;54:430-435. 2. Miller JM, Rosenthal ME, Vasallo JA, Josephson ME. Atrioventricular nodal reentrant tachycardia: studies on upper and lower “common pathways”. Circulation 1987:75:930-940. 3. Ross DL, Johhson DC, Denniss AR, Cooper MJ, Richards DA, Uther JB. Curative surgery for atrioventricular junctional (“AV nodal”) reentrant tachycardia. JACC 1985,6:1383S1392. 4. Cox JL, Holman WL, Cain ME. Cryosurgical treatment of atrioventricular node reentrant tachy-

Pacemaker Treatment of Sick Sinus Syndrome in Children

The sick sinus syndrome is being recognized with increasing frequency in children. Although it is sometimes benign, it can be serious or have fatal consequences. Fifty-one patients (mean age 10.5 years) underwent permanent cardiac pacing for sick sinus syndrome. Twenty patients had epicardial ventricular pacing and 12 had an epicardial atrial implant. Seven had endocardial atrial pacing, six epicardial atrioventricular (AV) sequential pacing, four epicardial universal pacing and two endocardial universal pacing. Of the 49 symptomatic patients, 45 had relief of symptoms. Eleven of 18 patients with associated tachyarrhythmias had amelioration of their tachycardia. There were no early but two late deaths unrelated to the pacemakers. Seven patients during a mean follow-up period of 26 months required reoperation for pacing lead or sensing problems. Permanent pacing for sick sinus syndrome in children is a safe and symptomatically effective procedure.

Intraoperative balloon valvuloplasty for critical aortic valvular stenosis in neonates

Abstract Critical aortic stenosis (AS) in the neonate represents a particularly severe form of AS where normal compensatory mechanisms are unable to maintain homeostasis, even at rest. Critical AS may be defined as aortic valve stenosis with congestive heart failure and signs of decreased systemic cardiac output. 1 When patients present in infancy with aortic valve stenosis and congestive heart failure, medical management is frequently unsuccessful. Various surgical procedures using both open and closed heart techniques have been attempted to relieve critical AS in infancy. 2–7 Percutaneous transluminal balloon valvuloplasty has been performed in patients with critical AS in infancy. 7 This procedure is technically difficult and at times impossible. The use of balloon valvuloplasty in the operating room has been described for the treatment of AS. 8,9 The technical aspects of intraoperative balloon valvuloplasty and the range of application are still being investigated. Reported complications include severe aortic regurgitation and disruption of an aortic valve cusp. This report describes the use of intraoperative balloon valvuloplasty in 4 neonates who presented with critical AS in the first week of life.

Surgery without angiography for neonates with aortic arch obstruction

Traditional diagnostic assessment of the neonate and infant with congenital abnormalities of the aorta causing left ventricular outflow tract obstruction has required catheterization and angiography. However, these patients frequently present critically ill and invasive diagnostic procedures may be associated with significant risks. Two-dimensional echocardiography has been used for aiding diagnosis of aortic arch abnormalities, but there has been little information concerning its use as the definitive imaging technique for preoperative assessment. We reviewed neonates who required urgent surgery for congenital obstruction of the aorta. The diagnosis was made using two-dimensional echocardiographic imaging and Doppler techniques for hemodynamic assessment in lieu of catheterization and angiography in all. Anatomic detail provided by the noninvasive approach was both sensitive and specific in guiding surgery in all but one case. We conclude that echocardiography eliminates the need for invasive preoperative diagnostic procedures in selected neonates with congenital aortic arch obstruction.

Infusion of blood from pericardial sac into femoral vein: a technique for survival until operative closure of a cardiac perforation during balloon septostomy

Technique employee chez un nourrisson presentant une laceration de loreillette gauche, une tamponade et un choc apres septostomie pour transposition des gros vaisseaux

Experience with the ST. JUDE MEDICAL® Valve and the IONESCU-SHILEY® Bovine Pericardial Valve at the Texas Heart Institute

Over the past 6 years surgeons at the Texas Heart Institute have implanted the IONESCU-SHILEY® bovine pericardial valve and the ST. JUDE MEDICAL® mechanical heart valve. Between July 1978 and September 1983, 2680 patients had valve replacement with the IONESCU-SHILEY® valve with a mean follow-up of 24.6 months and a maximum follow-up of 73.8 months. Between November 1978 and October 1983, 615 patients underwent valve replacement with the ST. JUDE MEDICAL valve with a mean follow-up of less than 10 months and a maximum of 60 months. Both prostheses are suitable choices for a valve substitute. Each has a low profile, can be implanted easily, has favorable hemodynamic characteristics and a low incidence of thromboembolism. While the incidence of failure of the IONESCU-SHILEY bioprosthesis is still low to 5 years, we are concerned that this incidence may increase with longer follow-up. In our experience with ST. JUDE MEDICAL valves, structural failure has not occurred up to 5 years after implantation. We currently favor using the ST. JUDE MEDICAL valve in all patients requiring valve replacement except in those who cannot take warfarin anticoagulation.