Ashok V. Mehta

Ventricular septal defect in the first year of life

Of approximately 22,000 live births in the region under study during the last 4 years, ventricular septal defect (VSD) was identified as the primary or isolated congenital heart lesion in 124 infants who were followed up from birth for a minimum of 1 year (incidence, 5.7 per 1,000 live births). Doppler color flow mapping was performed in 93 of 124 patients; 47 had a muscular VSD and 46 had a perimembranous VSD. Only 1 patient had 2 muscular VSDs. None had a subpulmonic type of defect. Of 124 patients, 14 were lost to follow-up. Spontaneous closure was seen in 18 patients (42%) in the muscular group, in 9 (23%) in the perimembranous group and in 10 patients (37%) in the unclassified group by the end of the first year. The overall rate of spontaneous closure was 34% by the end of the first year. Congestive heart failure developed in 2 of 46 patients with muscular VSD and in 12 of 47 patients with perimembranous VSD. In the first year, 2 patients with muscular VSD as opposed to 5 with perimembranous VSD required surgery. Doppler color flow mapping is a valuable aid in the diagnosis of VSD and may be one reason for the observed increase in the incidence of VSD. The overall prognosis appeared much better in the muscular than the perimembranous type of VSD.

Familial Symptomatic Sinus Bradycardia: Autosomal Dominant Inheritance

Symptomatic sinus bradycardia, due to either sick sinus syndrome or vagotonia, can be familial, affecting several members of a family. We report an 18-year-old male patient with palpitations and limited exercise capacity who was noted to have severe sinus bradycardia. His resting heart rate was 40/min, with normal PR and corrected QT intervals, and sinus pauses up to 6 seconds during sleep. Exercise treadmill test and pharmacologic autonomic blockade during electrophysiologic studies abolished the bradycardia, suggestive of vagotonia rather than intrinsic sinus node dysfunction. This patients father and a female cousin had a similar clinical history but associated with syncope and severe sinus bradycardia. The mode of transmission appeared to be autosomal dominant. All three have permanent demand pacemakers implanted and are asymptomatic.

Urokinase treatment of neonatal aortoiliac thrombosis caused by umbilical artery catheterization: A case report

Umbilical artery catheterization is known to be associated with aortoiliac thrombosis in approximately 1% of newborns in whom catheters are placed. We describe a case of catheter-associated aortoiliac thrombosis in a newborn who was successfully treated by urokinase infusion. The infant was monitored by imaging studies followed by ultrasonography. The use of real-time ultrasonography enabled us to image this infants aortoiliac thrombosis in an accurate, noninvasive manner and monitor the effectiveness of thrombolytic therapy. The fibrinolytic state was achieved with a combination of intravenous and intraarterial infusions of urokinase. Frequent measurement of prothrombin time, activated partial thromboplastin time, fibrinogen, and thrombin time was used to guide fibrinolytic therapy. We reviewed the literature for similar cases of aortoiliac thrombosis in newborns; some were managed by medical means, others by operation. The success rate of the two approaches appeared to be approximately equal. Therefore we recommend the less invasive approach first--urokinase therapy--to be followed by surgical intervention if thrombolysis is unsuccessful.

Verapamil-induced gingival hyperplasia in children

Gingival hyperplasia (GH) occurs in 20 % to 40 So of all patients receiving long-term oral phenytoin therapy and phenytoin is probably the most common cause of GH in children and young ado1escents.l Several other drugs including nifedipine, a calcium channel blocker, have been reported infrequently to cause GH.2-4 We report here a similar GH in two children following the long-term administration of a large dose of verapamil for the management of supraventricular tachycardia (SVT). Verapamil-associated GH has not been reported previously in the English literature. Case Ntj. 1. SL is a 12-year-old girl who was first noted to have tachycardia during the prenatal period. She had a trial of digoxin, quinidine, and propranolol in high doses in various combinations, with partial control of her SVT. At 3 years of age, a diagnosis of a permanent form of junctional reciprocating tachycardia (long R-P’ tachycardia) was made by electrophysiologic study, and an intravenous verapamil trial (0.2 mg/kg) was successful. She had no ventricular dysfunction by echocardiography. She was started on oral verapamil, 80 mg twice a day (9 mg/kg/day), with partial control, and was maintained on a similar dose with respect to body weight for the next 4 years. At 7 years of age, she was changed to sustained-release verapamil, 240 mg twice a day (15 mg/kg/day). Following 2 weeks of therapy on this dose, her verapamil level was 1030 Fg/L and 590 PglL at 6 hours and 12 hours, respectively, after the oral dose of verapamil (therapeutic trough level 100 to 600 pg/ L). Following 6 weeks of verapamil therapy, she developed marked GH. The labial gingivae of the anterior maxillary and mandibular teeth were firm, red, and nodular, with minimal bleeding. Despite good dental hygiene and frequent dental visits, she had persistent GH. There were no other adverse effects of verapamil. At 11 years of age verapamil was discontinued because of partial control of the tachycardia. Six weeks later her GH significantly improved. Subsequently she was started on a regimen of oral propafenone without success. At present she is maintained on a regimen of oral Aecainide with fairly good control of the tachycardia. Case No. 2. DM is a 16-year-old young woman patient who was noted to have a tachycardia during the prenatal

Long-term efficacy and safety of atenolol for supraventricular tachycardia in children

Propranolol, a first-generation nonselective β-adrenoceptor blocking agent, is commonly used to treat pediatric arrhythmias. Atenolol, relatively longacting, cardioselective β-adrenoceptor blocking agent, has been successfully used in adults with supraventricular tachycardia (SVT). There is only one report on the use of atenolol in children with SVT, and our report is on the first long-term prospective study to evaluate the use of atenolol in children. A group of 22 children <18 years of age with clinical SVT were enrolled in the study. The tachycardia was documented on electrocardiograms in each case and was confirmed by electrophysiologic studies in some. Once-a-day oral atenolol was started as a monotherapy. Of the 22 children with various types of SVT, 13 (59%) were well controlled on long-term oral atenolol therapy. The effective dose of atenolol ranged between 0.3 and 1.3 mg/kg/day (median effective dose 0.7 mg/kg/day). Five children had some adverse effects. However, none in the successful group of 13 patients required drug discontinuation because of such effects. Once-a-day oral atenolol as a monotherapy is effective and relatively safe for long-term management of SVT during childhood. It is an attractive alternative β-adrenoceptor blocking agent for the management of pediatric arrhythmias.

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.

Pharmacokinetics of Nadolol in Children with Supraventricular Tachycardia

The pharmacokinetics of intravenous and oral nadolol, a long‐acting β‐adrenoceptor blocking agent, were investigated in six children receiving the drug for treatment of supraventricular tachycardia. In the youngest patient (age 3 months), no distribution phase was seen. In children younger than 22 months of age, nadolol is more rapidly eliminated (t1/2 = 4.3 hours or less) than in older children, in whom elimination is more similar to that in adults (t1/2 ∼ 7.3–15.7 hours). After intravenous administration, nadolol displayed two‐compartment pharmacokinetics with a distribution phase (t1/22 = 0.2–1.1 hours) followed by elimination. Large changes in nadolol pharmacokinetics may occur during the first year of life. Nadolol should be used cautiously in infants.

Absent left pulmonary vein without anomalous connection: Diagnosis and management in the newborn

Unilateral atresia of the pulmonary vein is an uncommon condition and is often associated with partial anomalous venous connection. Various forms of alternative channels have been described.l-” While the term “atresia” is used to denote the existence of a variable size and length of cordlike pulmonary veins without any lumen, “absence” is used here to denote that no such connection exists between the pulmonary hilum and left atrium, as a result of either agenesis or involution. To our knowledge, only two cases of unilateral absence of the pulmonary vein without anomalous connection have been reported in the English literature.4 We report a case of unilateral pulmonary edema caused by an absent left pulmonary vein without anomalous connection, diagnosed and managed successfully by surgery in a newborn. A full-term male infant (birth weight 3011 gm) was born by emergency cesarean section because of fetal bradycardia to a 23-year-old gravida I, white female. The child was

Experience with moricizine HCl in children with supraventricular tachycardia

Eight children, age between 4.5 and 19 years were treated with moricizine for supraventricular tachycardia during the last 3 years. The tachycardia was documented by surface electrocardiogram (ECG), and/or by ambulatory ECG in all the children and the mechanism of tachycardia was determined by previously published surface ECG and electrophysiologic criteria in all but one child. Of the eight children, three had atrial ectopic tachycardia, three had automatic junctional ectopic tachycardia, one had atrioventricular (AV) nodal reentry tachycardia and one had atrial reentry. All the children except one had failed trial of two or more antiarrhythmic drugs prior to moricizine therapy. The duration of moricizine therapy ranged from 4 days to 25 months. In three of the eight children (patients 3, 5 and 7), who presented with AV nodal reentrant tachycardia, automatic junctional ectopic tachycardia and atrial ectopic tachycardia, respectively, moricizine therapy was effective in restoring sinus rhythm and controlling the clinical tachycardia. Only one child (patient 1) developed proarrhythmia, an episode of fast, narrow-QRS supraventricular tachycardia lasting for 30 s, on the third day of therapy. This was subsequently confirmed by electrophysiologic study to be AV nodal reentrant tachycardia. The other side effects noted were non-cardiac, not dose-dependant and did not require dis-continuation of therapy. Based on our small series and those of others, moricizine, a newer class I anti-arrhythmic agent, has a limited but useful role in the management of recalcitrant type of supraventricular tachycardia, such as ectopic atrial and junctional tachycardia in children.

Mitral valvar prolapse and regurgitation combined with aortic regurgitation in a child with Sanfilippo syndrome type A

Cardiovascular involvement is commonly reported in various muco- polysaccharidoses. We report a first case of Sanfilippo syndrome type A in a 12-year-old white female who has developed combined progressive mitral valvar regurgitation due to prolapse and aortic regurgitation.