Fetal atrioventricular septal defect associated with Patau and Edwards syndromes, as well as trisomy 22

The atrioventricular septal defect is usually associated with trisomy 21 and it may be observed in the heterotaxia syndromes. Atrioventricular septal defect may be associated with 8p deletion. There are reported cases of familial atrioventricular septal defect. Atrioventicular septal defect is rarely associated with other chromosomal abnormalities. We are reporting three unusual cases of atrioventricular septal defect that were associated with trisomy 13, 18 and 22. This association may be due to effect of genetic loci on the 13, 18 and 22 chromosome which could play the role in the development and fusion of endocardial cushion and atrioventricular septal defect.     

Congenitally corrected transposition with atrioventricular septal defect

We describe 4 cases of congenitally corrected transposition associated with atrioventricular septal defect, diagnosed by echocardiography and angiocardiography. Two had usual atrial arrangement and two had mirror imaged atrial arrangement . All cases were associated with subpulmonary valvar stenosis. All patients presented with cyanosis and were in sinus rhythm. Atrioventricular septal defect with common atrioventricular junction was easily diagnosed on the basis of a common atrioventricular valve permitting interatrial and interventricular communications. All patients had balanced right and left ventricles. The echocardiographic recognition of the ventricles was based on the presence of the moderator band within the morphologically right ventricle, the characteristics of the apical septal trabeculations, and the shape of the ventricles. Angiocardiographic recognition of the ventricles was achieved on the basis of right and left ventriculography. In one case with usual atrial arrangement, we recorded two His bundle potentials, one anteriorly and another posteriorly. Atrial stimulation revealed blocked atrioventricular conduction at the level of the posterior bundle, and normal atrioventricular conduction through the anterior bundle. In both cases with atrial mirror-imagery, only a posterior His bundle potential was found, with normal atrioventricular conduction revealed by atrial stimulation The clinical course with this combination depends on the other lesions present in addition to the common atrioventricular valve. Our electrophysiological studies show that the conduction system in presence of a common atrioventricular valve is as expected for congenitally corrected transposition with two atrioventricular valves.     

Monocusp homograft VSD patch in atrioventricular canal with tetralogy of Fallot

A monocusp aortic homograft was used to compensate for deficient right atrioventricular valve tissue during repair of complete atrioventricular canal defect with tetralogy of Fallot. The homograft was used to produce a comma-shaped ventricular septal defect patch together with the septal leaflet of the right atrioventricular valve, thus committing native leaflet tissue to left atrioventricular valve reconstruction. One year postoperatively the child is in New York Heart Association class I with no tricuspid regurgitation.     

Anatomically sound, simplified approach to repair of "complete" atrioventricular septal defect

BACKGROUND: There are few congenital anomalies of the heart that have benefited more from thorough anatomic analysis than the complex anomaly known as atrioventricular septal defect in the setting of common atrioventricular junction. Recent advances in understanding the anatomy of this lesion have led to alternative methods of repairing these defects. METHODS: The medical records of 21 consecutive patients undergoing repair of complete atrioventricular septal defect have been reviewed. Nine of these patients had a standard one- or two-patch repair, and 12 had direct closure of the ventricular element of the defect. RESULTS: Direct closure resulted in significantly shorter pump and cross-clamp times. Follow-up for an average of 34 months suggests that when direct closure can be performed, the results are comparable with those of the more standard technique. CONCLUSIONS: Our initial success with this approach is encouraging; however, longer follow-up is required to establish whether it will be broadly applicable.     

Size of ventricular structures influences surgical outcome in Down syndrome infants with atrioventricular septal defect

To evaluate the relation between ventricular structure size and surgical outcome in Down versus non-Down syndrome infants with an atrioventricular septal defect, we reviewed the charts and echocardiograms of 44 consecutive infants (34 with Down syndrome) who underwent atrioventricular septal defect repair. Children with Down syndrome had significantly greater aortic valve diameters, left ventricular valve areas, and left/right atrioventricular valve area ratios as well as fewer adverse outcomes than non-Down syndrome children.     

Pulmonary vascular disease and operative indications in complete atrioventricular canal defect in early infancy

Pulmonary vascular disease was morphometrically analyzed in 67 patients (mean age, 19 months) with isolated complete atrioventricular canal defect. Complete obstruction of the small pulmonary arterial lumen resulting from acute fibrous proliferation and atrophy of the peripheral arterial media, which were considered absolute operative contraindications, were characteristic in six patients with Down's syndrome. Morphometric analysis of medial thickness revealed that thinning of the media of the small pulmonary arteries is generally observed at around 6 months of age in patients with complete atrioventricular canal defect and that the media in patients who have complete atrioventricular canal defect and Down's syndrome was thinner than that in such patients without Down's syndrome. These results suggest that thinning of the media as a result of two factors--Down's syndrome and aging--facilitates the rapid occurrence of fibrous intimal proliferation. Therefore intracardiac repair is desirable within 6 months of life, before medial thinning, in patients with complete atrioventricular canal defect and Down's syndrome. Excluding patients with absolute operative contraindications, the scores of the index of pulmonary vascular disease in operative survivors were below 2.0 and death occurred when scores were more than 2.2. The pulmonary vascular resistances measured in room air and by the oxygen inhalation and tolazoline tests in patients with operative contraindications were more than 7.3, 3.8, and 6.6 units.m2, respectively. We thus conclude that lung biopsy should be undertaken for patients in whom pulmonary vascular resistance is beyond these values to determine the appropriateness of surgical intervention.     

First degree atrioventricular block caused by a calcified tumor of the atrioventricular septum

First degree atrioventricular block occurred in a 69-year-old patient with a calcified atrioventricular septum tumour. The patient suffered several episodes of syncope and the only abnormality found in the routine clinical work-up was a remarkable first degree atrioventricular block. The echocardiogram, computed tomography (CT) and the magnetic resonance imaging (MRI) procedure showed a calcified tumour in the posterior part of the left ventricle, between the left atrium and left ventricle, just beneath the aortic root spreading to the interventricular septum. It was suggested that the first degree atrioventricular block was caused by the tumour. The symptoms were relieved by implantation of permanent cardiac pacemaker.     

Paroxysmal atrial tachycardia with second-degree atrioventricular block

Paroxysmal atrial tachycardia with atrioventricular block usually indicates potentially dangerous overdigitalization, and serious heart disease is almost universally present. In this report, we describe a patient with a structurally normal heart who manifested spontaneously intra-atrial reentrant tachycardia with Wenckebach atrioventricular block in the absence of medications. In this patient, the longest atrial paced cycle length that induced atrioventricular nodal block was 390 ms, and the atrial cycle length during tachycardia ranged from 360 to 400 ms. The electrophysiologic study in our patient demonstrated that second-degree atrioventricular block during atrial tachycardia may occur in patients without structural heart diseases or taking any medication.     

Predisposing factors of valve regurgitation in complete atrioventricular septal defect

OBJECTIVES: We sought to determine the intrinsic risk factors of valve regurgitation in complete atrioventricular septal defect. BACKGROUND: Progression of regurgitation varies in each case, although the structure of the common atrioventricular valve itself is a predisposing factor. METHODS: In 90 consecutive patients undergoing surgical repair, we evaluated the preoperative and postoperative regurgitation, valve morphology, age at surgery and associated anomalies. A regurgitation jet with a high velocity reaching the deep left atrial wall by echocardiography was estimated as marked regurgitation. RESULTS: None of the 40 patients with Rastelli type C and an undivided inferior bridging leaflet had preoperative regurgitation in the first year of life, and 12% of them (95% confidence intervals [CI]: 0% to 28%) showed regurgitation at the age of 2. Of the remaining 50 with Rastelli type A and/or a divided inferior leaflet, regurgitation was determined in 21% (95% CI: 6% to 35%) of those 1 year old and in 49% (95% CI: 29%7 to 69%) of those 2 years old (p < 0.01). All patients underwent corrective surgery using the double-patch technique, with the "cleft" being sutured adequately. Irrespective of the valve morphology, regurgitation remained in 52% (12 of 23) of those with preoperative regurgitation, whereas regurgitation developed postoperatively in 28% (16 of 58) of those without regurgitation (p < 0.001). CONCLUSIONS: Those with Rastelli type C and an undivided inferior leaflet had a lesser degree of progression of preoperative regurgitation. However, regurgitation was likely to exist even after adequate repair once regurgitation had already advanced. Therefore, early primary repair before progression of the regurgitation may be the key to maintaining better competence of the atrioventricular valve.     

Repair of the left AV valve in atrioventricular septal defect in adults

BACKGROUND: This study examined the septal cleft and septal commissure of the left atrioventricular (AV) valve, which are two different anatomical structures. METHODS: We presented 36 cases of adult partial atrioventricular septal defect. A distinction was made between patients based on the anatomy of the anterior leaflet of the left AV valve. The left AV valve appeared to be normal or to have minimal radial openings from the free edge of the anterior leaflet of the left AV valve in 10 patients (28%). There was a septal commissure structure in 8 (22%), and a septal cleft structure in 18 (50%) patients. In the commissure type anatomy, leaflet coaptation was usually adequate and no or mild degree of left AV regurgitation existed preoperatively. Cleft type structure usually was associated with some degree of left AV regurgitation. Attempts were made to close the septal clefts and leave the septal commissures unsutured during the repair of the partial AV septal defects. RESULTS: We have not found any increase of left AV regurgitation in patients with commissures during the follow-up period. Closure of the cleft successfully eliminated regurgitation. Long-term results for septal cleft and septal commissure after repair of partial AV septal defect were excellent with survival of 100% and freedom from reoperation of 100% at mean 6.5 years. CONCLUSIONS: Septal cleft and septal commissure should be considered two different structures. Repairing procedures for left AV valve abnormalities associated with partial AV septal defect should only be done in patients who have cleft type of leaflet structure.     

Primary repair is superior to initial palliation in children with atrioventricular septal defect and tetralogy of Fallot

OBJECTIVE:The objective was to explore the best management algorithm for atrioventricular septal defect in conjunction with tetralogy of Fallot. METHODS: We reviewed the cases of 38 children referred to our division (March 1981-August 1997) who had atrioventricular septal defect associated with tetralogy of Fallot; 32 (84%) had Down syndrome. Twenty-one received initial palliation with a systemic-to-pulmonary artery shunt; of these, 2 (9.5%) died before complete repair. Thirty-one children underwent complete repair; 14 of these (45%) had undergone initial palliation (mean age at shunt 20 +/- 24 months). Right ventricular outflow obstruction was relieved by a transannular patch in 22 (71%); 14 (64% of 22) had a monocuspid valve inserted. Four required an infundibular patch. RESULTS: Two children (6.4%) died early after repair; 1 had undergone previous palliation. Patients with palliation underwent repair at an older age (78 vs 36 months), required longer ventilatory support (8 vs 4 days) and inotropic support (8 vs 4 days), and had longer intensive care stays (11 vs 6 days) and hospital stays (24 vs 15 days). Eleven children (35%) underwent reoperation, 7 (58%) for right ventricular outflow reconstruction and pulmonary arterioplasty. Reoperation was more frequent in the palliation group than in the primary operation group (64% vs 12%). The single late death was related to a reoperation in the palliation group. CONCLUSIONS: Atrioventricular septal defect with tetralogy of Fallot can be repaired with a low mortality rate. Initial palliation with a shunt resulted in a more complex postoperative course and a higher reoperative rate. Primary repair is superior to initial palliation with later repair.     

Atrioventricular valve function after single patch repair of complete atrioventricular septal defect in infancy: how early should repair be attempted?

BACKGROUND: Though repair of complete atrioventricular septal defect in infancy has become routine at most centers, it is not unusual for very young infants to be managed medically because of concerns about the fragility of the atrioventricular valve tissue. METHODS: Since July 1992, seventy-two infants have undergone primary repair of complete atrioventricular septal defects at a median age of 3.9 months (40% < 3 months). A single-patch technique was used in all patients. The cleft was closed completely in 61 patients and partially (n = 10) or not at all (n = 1) in select patients at risk for valve stenosis. Left atrioventricular valve annuloplasty was performed in 18 patients. On the basis of transesophageal echocardiographic findings, 10 patients were returned to bypass for revision of the valve repair. RESULTS: There was one early death in a patient with single left papillary muscle, no early reoperations, and no new permanent arrhythmias. Only three patients had moderate left atrioventricular valve regurgitation at discharge. During a median follow-up of 24 months, there was one late death and five reoperations for left atrioventricular valve regurgitation (n = 2) and/or systemic outflow obstruction (n = 4). Follow-up left atrioventricular valve regurgitation was moderate in three patients, mild in 14, and none/trace in 54. Age had no relation to postoperative atrioventricular valve regurgitation, death, or reoperation. CONCLUSIONS: Despite concerns about fragility of valve tissue in very young patients, excellent results can be achieved with meticulous techniques. From neonates to older infants, age at repair does not influence outcome or valve function.     

Impact of heart rate and atrioventricular delay on left ventricular diastolic filling in patients with dual-chamber pacing for sick sinus syndrome or atrioventricular block

We examined the effect of left ventricular filling on different combinations of programmable heart rate and atrioventricular delay in patients with dual-chamber pacemakers. Pacing mode with heart rates of 60 beats/min and 156 ms of atrioventricular delay induced a diastolic pattern that resembles more than others the one observed in healthy subjects in sinus rhythm.     

Congenital complete atrioventricular block and prolapsing mitral valve

Congenital complete atrioventricular block and prolapsing mitral valve are described in a 41-year-old woman who exhibited ventricular arrhythmias and symptoms initially attributed to her atrioventricular block. The importance of physical examination to elicit clues in the diagnosis of prolapsing mitral valve is emphasized.     

Transcatheter radiofrequency ablation. Early experience with supraventricular tachyarrhythmias related to accessory atrioventricular and dual atrioventricular nodal pathways

OBJECTIVE: To describe our initial experience with transcatheter radiofrequency ablation, a useful new treatment for supraventricular tachyarrhythmias related to the presence of an accessory atrioventricular (AV) pathway or dual atrioventricular nodal pathways. PATIENTS AND METHODS: One hundred and ten patients, including 77 with accessory pathways, 32 with dual atrioventricular (AV) nodal pathways and one with both, underwent electrophysiological studies and were treated with transcatheter radiofrequency ablation in a large metropolitan teaching hospital. RESULTS: Ninety-five patients (86%) were without evidence of accessory pathway conduction or inducible supraventricular tachycardia and were free of symptoms after a mean follow-up of 13 months (range, 3.0-51 months). Sixty-six of 79 accessory pathways (83.5%) were ablated including 42 of 46 left-sided (91%), 14 of 21 posteroseptal (66%), six of seven anteroseptal (86%), three of four right-sided and one of one midseptal pathways. Thirty-one patients with AV nodal reentry were successfully treated by ablation of either the slow (12 patients) or fast (19 patients) conducting AV nodal pathway. There was a progressive improvement in the success rate of the first procedure from 17% to 64% with the use of large-tip catheters and from 64% to 91% when a purpose-built radiofrequency generator was employed. Complications occurred in nine patients: cardiac tamponade (two patients); mild mitral regurgitation (four); subclavian vein thrombosis (one); transient cerebral ischaemic attack (one); and non-thrombocytic purpuric rash (one). These occurred predominantly during the early experience and were without long-term sequelae. Late in our experience, one patient developed complete atrioventricular block requiring permanent pacemaker implantation. CONCLUSIONS: In this institution, radiofrequency catheter ablation has been a safe and effective treatment strategy for patients with life-threatening or highly symptomatic supraventricular arrhythmias.     

Atresia of the right atrioventricular orifice

The results are reported of a study of 83 necropsied hearts with atresia of the right atrioventricular orifice. It is emphasised that right atrial or atrioventricular orificial atresia is a better term to describe this anomaly than "tricuspid atresia". Use of the latter term can be confusing when the morphologically tricuspid valve is located beneath the left atrium. It is accepted that the definition employed may include cases in which the mitral valve may be atretic, blocking normal exit from the right atrium, but it is argued that such cases would present clinically as "tricuspid atresia" and therefore are correctly designated as right atrial orificial atresia. The results show that the majority of hearts with right atrial orificial atresia have the ventricular morphology of primitive ventricle, most with, but a few without an outlet chamber. However, in a minority of hearts an imperforate membrane interposes between the right atrium and a formed but hypoplastic right ventricle. In two of the hearts, the imperforate membrane showed features of Ebstein's malformation. The hearts could be further subdivided according to the ventriculoarterial connection. Most had normally connected arteries (66 of 83), and all but 2 also had normal relations between the arteries; in these 2 hearts there was "anatomically corrected malposition". Twelve hearts showed transposition, one had double-outlet outlet chamber, and another persistent truncus arteriosus. The remaining 3 hearts, all without outlet chamber, had by definition a double outlet connection. A segmental approach provides the best way of classifying this anomaly, and an embryological explanation is offered for the variations in anatomy observed.     

Double switch operation in cardiac anomalies with atrioventricular and ventriculoarterial discordance

Since June 1987, 10 of 19 consecutive patients with atrioventricular and ventriculoarterial discordance (average age 4 +/- 2 years) had undergone a double switch operation with the morphologically left ventricle used as a systemic ventricle. There were two combinations of procedures. Atrial switch combined with arterial switch was used in two patients who had a normal pulmonary valve. Atrial switch combined with ventriculoarterial switch by Rastelli's procedure was used in eight patients with pulmonary stenosis or atresia and a large ventricular septal defect. One early death and two late deaths have occurred in a postoperative follow-up period of up to 4 years. Subsequent problems were mainly related to the results of atrial switch procedures in patients who had a small atrium because of low pulmonary flow, especially in patients with apicocaval juxtaposition. Our experience suggested that the double switch operation would open a new era of definitive surgical treatment in half of the patients with atrioventricular and ventriculoarterial discordance.     

Duration of complete atrioventricular block after congenital heart disease surgery

Children with complete heart block following surgery for congenital heart diseases were prospectively followed to assess the timing for recovery of atrioventricular conduction, and to determine if there were clinical variables that reliably predict permanent heart block. Recovery of atrioventricular conduction occurred by postoperative day 9 in 97% of patients with transient heart block.     

Variation of P-QRS relation during atrioventricular node reentry tachycardia

OBJECTIVES: The main objective of this study was to characterize the phenomenon of variation in the P-QRS relation during atrioventricular node reentry tachycardia. BACKGROUND: Variation of P-QRS relation during tachycardia has been observed occasionally in atrioventricular node reentry tachycardia. However, the incidence, the characteristics and the mechanisms of this phenomenon have not been investigated previously. METHODS: Retrospective analysis was performed in 311 consecutive patients with slow-fast form and 108 patients with atypical or multiple form of atrioventricular node reentry tachycardia to examine whether variation of P-QRS relation with changes in AH, HA and AH/HA (A = atria; H = His bundle) ratio occurred during tachycardia. RESULTS: A total of 28 patients, 8 with slow-fast and 20 with atypical or multiple tachycardias, were found to manifest this phenomenon. There were 6 males and 22 females, with an average age of 38+/-16 years. In 10 patients, this phenomenon occurred transiently following electrical induction of the tachycardia. In 15 patients, changes in AH, HA and AH/HA ratio were associated with the occurrence of Wenckebach or 2:1 block proximal to the His bundle (H) recording site without interruption of the tachycardia. In nine patients, three with nonsustained tachycardia and six after administration of adenosine triphosphate, this phenomenon was observed at the termination of the tachycardia. This phenomenon was usually accompanied by a mild lengthening of the tachycardia cycle length. CONCLUSIONS: Variation of P-QRS relation with or without block may occur during atrioventricular node reentry tachycardia, especially in atypical or multiple-form tachycardias. It was postulated that decremental conduction in the distal common pathway, which exists between the distal link of the reentry circuit and the H, is primarily responsible for this phenomenon.