Page 44 - Journal of Structural Heart Disease Volume 2, Issue 1

Original Research Article
38
Base line EKG
At baseline, all patients had 12-lead EKG prior to VSD closure. EKG was normal in 40 (89%) patients and abnormal in 5 (11%) patients [4 incomplete right bundle branch block (ICRBBB) and 1 complete right bundle branch block (CRBBB) (Figure 1)].
Latest EKG
long-term follow up.
Interestingly, we noted resolution of ICRBBB in two
of the four who had it at baseline EKG before closure and both had normal EKG at all follow-up visits. Of the other two patients of ICRBBB at baseline, one pro- gressed to CRBBB and one maintained the same after device closure.
For all groups at long-term follow up, no mortal- ity, stroke or neurologic de cit, device migration, wire fracture, thromboembolism, endocarditis, or hemolysis was seen.
Discussion
Nonsurgical closure of VSD has been an attractive option to avoid arti cial circulation and sternotomy scars. The Amplatzer muscular occluder has been suc- cessfully used to close muscular VSDs [6, 7] and a spe- cially designed Amplatzer ventricular septal occluder has been used in perimembranous defects [8, 10, 14]. The Amplatzer duct occluder has been used success- fully for the closure of tunnel-type VSDs with aneu- rysmal tissue [11, 12]; recently, ADO - II has been tried with good success rates and minimal rhythm distur- bances [13]. One of the major drawbacks for membra- nous VSD closure is the signi cant incidence of heart block and rhythm abnormality. In one study, the CAVB was reported as high as 5.8% [17] with the need for pacemaker therapy. In other studies, the major ad- verse events have been reported as low as 0.6% in pm- VSD patients under 3 years of age using symmetrical devices [15]. Late occurrence of CAVB also has been re- ported at 1 year follow up [20]. The junctional rhythm at early (within 48 hours) post-device pmVSD implan- tation indicates an in ammatory process around the atrioventricular node. Some studies showed occur- rence of early post-implantation junctional rhythm up to 14% of their patients [15]. This can explain the observed bene t of steroid administration in some patients who developed CAVB early post-device implantation [15].
We showed a low incidence of CAVB in one (2.9%) patient in the pmVSD group with a mean follow up of 62 months. This patient developed CAVB between 6 and 12 months post-implantation, remained as- ymptomatic, and was diagnosed by routine EKG. This warrants the necessity of long-term follow up of all
During 8 year follow up, EKG ndings were ana- lyzed in all 45 subjects. At a median follow up of 61.9 months, EKG revealed one patient with muscular VSD had developed ICRBBB. There were total 5 patients with CRBBB at the latest follow up. Out of these 5 pa- tients, 3 patients had new onset CRBBB, fourth patient had progression of base line ICRBBB to CRBBB and in the fth patient the base line CRBBB persisted as it is at the latest follow up. All the patients with CRBBB were having pmVSD and they received a pmVSD Am- platzer device of mean size 10.5 mm at a mean age of 9.4 years and weight of 26.7 kg. There was no CRBBB observed in muscular VSD patients at follow up.
Complete left bundle branch block (CLBBB) was seen in two (4%) patients in this cohort, one had pmVSD and one had muscular VSD. Both patients re- ceived muscular VSD Amplatzer devices (6 mm size) and their mean age and weight were 4.3 years and 19.5 kg, respectively.
Complete atrioventricular block occurred in one (2.9%) of the patients in the perimembranous VSD group. This patient received a 12-mm membranous type Amplatzer device, and his age and weight were 5 years and 17 kg, respectively. He developed CRBBB immediately after the procedure, which persisted for 6 months; at 1 year follow up, he was found to have CAVB and underwent placement of a permanent pacemaker.
Other arrhythmias observed in the pmVSD group included 3 beats run of ventricular tachycardia in one patient and ectopic atrial tachycardia in another pa- tient. Occasional premature ventricular contractions were observed in one of the cases from the muscu- lar VSD group (Tables 3 and 4). All the patients who received ADO Amplatzer devices (six patients with pmVSD and one muscular VSD) had no arrhythmia or conduction abnormality at either immediate or
Journal of Structural Heart Disease, February 2016
Volume 2, Issue 1: 35-41