Early and Long-Term Clinical Outcomes of Ductal Stenting Versus Surgical Aortopulmonary Shunt Among Young Infants with Duct-Dependent Pulmonary Circulation.

Surgical aortopulmonary shunting (SAPS) and ductal stenting (DS) are the main palliations in infants with cyanotic congenital heart diseases (CHD). We aimed to study the safety and efficacy of DS and to compare it with SAPS as a palliative procedure in infants with CHD and duct-dependent pulmonary circulation. Retrospective institutional clinical data review of consecutive infants aged < 3 months who underwent DS or SAPS over 5 years. The primary outcome was procedural success which was defined as event-free survival (mortality, need for re-intervention, procedural failure) at 30 days post-procedure. The secondary outcome was defined by a composite of death, major adverse cardiovascular events, or need for re-intervention at 6 months and on long-term follow-up. We included 102 infants (DS, n = 53 and SAPS, n = 49). The median age at DS and SAPS was 4 days (IQR 2.0-8.5) and 8 days (IQR 4.0-39.0), respectively. The median weight at intervention was 3.0 kg (IQR 3.0-3.0) and 3.0 kg (IQR 2.5-3.0) in the two respective arms. Tetralogy of Fallot with pulmonary atresia was the most common indication for DS and SAPS. The 30-day mortality was significantly higher in SAPS group as compared with DS group (p < 0.05). However, 30-day major adverse cardiac events (MACE) rates were similar in both groups (p = 0.29). DS was associated with shorter duration of mechanical ventilation, duration of stay in the intensive care and hospital stay than with SAPS. At 6 months, there was no significant difference in terms of mortality or event-free survival. Long-term MACE-free survival was also comparable (p = 0.13). DS is an effective and safer alternative to SAPS in infants with duct-dependent pulmonary circulation, offering reduced procedure-related mortality and morbidity than SAPS. Careful study of ductal anatomy is crucial to procedural success. However, long-term outcomes are similar in both procedures.

Left cardiac sympathetic denervation in children with Jervell Lange-Nielsen syndrome and drug refractory torsades - A case series.

INTRODUCTION: Long QT syndrome is an inherited malignant channelopathy which leads to life-threatening arrhythmia, with multiple genotypes. Jervell and Lange-Nielsen syndrome (JLNS) is an autosomal recessive subtype of this disease, characterized by congenital sensorineural deafness and a high incidence of sudden cardiac death (SCD). METHODOLOGY: We prospectively followed up six children who underwent left cardiac sympathetic denervation (LCSD) for JLNS in view of high-risk features despite being on maximally tolerated doses of oral propranolol. RESULTS: Mean age at diagnosis was 2.75 ± 0.39 years, with a significant delay between onset of symptoms and diagnosis (mean 7.2 ± 3.5 months). All had sensorineural hearing loss, conforming to the JLNS phenotype. Mean QTc interval was 603 ± 93 ms, with T wave alternans (TWA) seen in all cases. All were started on propranolol and subsequently subjected to LCSD, and 3 underwent AAI permanent pacemaker implantation. Over a mean follow-up of 20 months, there was a significant reduction in QTc (603 ± 93 ms to 501 ± 33 ms, p = .04), which was persistent on follow-up (525 ± 41 ms) and only two out of six had persistent T wave alternans on ECG (p < .01). None of these children had presyncope, syncope, seizures, torsades de pointes, cardiac arrest or death on follow up following LCSD. CONCLUSION: Jervell Lange-Nielsen syndrome is a subtype of LQTS with high-risk features. LCSD, an effective therapeutic option for those having symptoms despite being on propranolol, results in significant reduction of QTc interval and amelioration of symptoms.

Interesting phenomenon during positioning of the 3830 lead deep inside the septum by rapid rotations. What is the mechanism?

A 66-year-old lady having complete AV block with narrow QRS escape had undergone left bundle branch pacing (LBB) with 4.1-F diameter 3830 Select SecureTM pacing lead (Medtronic Inc., Minneapolis, MN, USA). The pacing lead was placed with the inter-ventricular septum, 2 cm inferior to the distal His region towards the right ventricular apex, by 5 rapid turns. During the rapid turns, an interesting phenomenon was noted [Fig. 1A & B]. What is the mechanism?

Study of atrial arrhythmias after surgical or device closure of atrial septal defect.

Background Device closure of atrial septal defect (ASD) has emerged as a treatment modality for the past 3 decades and has changed the natural history of ASD compared to that of surgical closure. Early intervention in ASD retards the geometrical and electrical remodelling of the atrium that contributes to the development of atrial tachyarrhythmias. We studied the incidence of atrial arrhythmias in patients undergoing surgical and device closure of ASD. Methods We did this retrospective observational study at a tertiary referral centre, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala. Patients of all age groups undergoing surgical and device closure of ASD between 1 January 2003 and 31 December 2008 were included to compare the incidence and nature of atrial arrhythmias and also analyse the difference in new-onset atrial arrhythmias between the two arms. Results Of 277 patients, 144 with surgical closure and 133 with device closure were followed up for 10-15 years. A larger number of men underwent surgical closure (41.7%) compared to device closure (25.6%). The mean (SD) follow-up was 12.6 (3.7) years in the surgical closure group and 10.9 (2.6) years in the device closure arm. There were a larger number of patients with atrial tachyarrhythmias in the surgical closure group (6.3%) compared to the device closure group (0.8%) at baseline (p=0.02). A significantly larger number of patients had atrial fibrillation in the surgical closure group (5.6%) compared to the device closure group (0.7%) at baseline (p=0.003). Pulmonary hypertension at baseline was present in 38.9% of patients in the surgical closure group and in 23.3% of patients in the device closure group (p=0.006). New-onset atrial arrhythmias occurred in patients ≥30 years of age (p=0.006) and exclusively in patients with pulmonary hypertension in the surgical group (3.7%) and in the device closure group (6.6%). This was statistically significant in the device closure group (p=0.05) but not in the surgical closure group (p=0.13). The incidence of new-onset arrhythmias was not statistically significant in both groups. Conclusions Atrial arrhythmias were significantly more common in patients who underwent surgical or device closure at ≥ 30 years of age and in patients with pulmonary hypertension. There was no difference in new-onset atrial arrhythmias between the surgical and device closure groups. Our study results suggest that surgical or device closure before 30 years of age and before the development of atrial arrhythmias may be beneficial with respect to the development of atrial arrhythmias.

Discordant responses to his refractory premature ventricular beats (PVBs) during a regular narrow QRS tachycardia. What is the mechanism.

A 32-year-old lady was evaluated for recurrent episodes of palpitation. During one of the palpitation episodes a regular narrow QRS tachycardia was documented, and it got terminated with the administration of IV adenosine. The baseline 12 lead electrocardiogram (ECG) did not show any manifest preexcitation. There was no evidence of structural heart disease by echocardiogram. Patient underwent an electrophysiology (EP) study after informed consent. Quadripolar catheters were placed at the His region and right ventricular (RV) apex. A decapolar catheter was placed in the coronary sinus (CS) with CS 9, 10 dipoles at CS OS region and CS 1, 2 dipoles at CS distal region. A mapping & ablation catheter was positioned at right atrial (RA) appendage. Baseline atrial and ventricular pacing protocols could not be performed as both atrial and ventricular pacing were easily inducing a regular narrow QRS tachycardia. His refractory premature ventricular beats [PVBs] were delivered from RVRV apex and left ventricular [LV] free wall. Discordant responses were obtained. What is the mechanism?

Regular narrow QRS tachycardia. What is the mechanism?

A 45-years-old lady with no structural heart disease on echocardiogram presented with recurrent episodes of palpitation. There was no baseline preexcitation. Twelve lead surface electrocardiograms (ECG) recorded during one of the episodes are provided. What is the likely mechanism of the tachycardia? [Figure: see text].

Transition during radiofrequency ablation of manifest preexcitation. What is the mechanism?

A 45-year-old lady was evaluated for recurrent episodes of palpitation. Her 12­lead electrocardiogram (ECG) showed manifest but incomplete pre-excitation consistent with left sided accessory pathway. There was no structural heart disease by echocardiogram. She underwent an electrophysiology (EP) study after informed consent. A narrow QRS tachycardia consistent with orthodromic AV re-entry got induced. The accessory pathway was mapped to 2 'O clock of the mitral annulus (MA). While radio frequency ablation (RFA) was being performed at that site, an interesting phenomenon was observed (Figs. 1 & 2). What is the mechanism?

A Comparative Study of Invasive Modalities for Evaluation of Pulmonary Arteriovenous Fistula after Bidirectional Glenn Shunt.

Development of pulmonary AV fistula (PAVF) after bidirectional glenn shunt (BDG) results in significant cyanosis, impaired exercise performance, and increased morbidity and mortality. We attempted to detect and quantify PAVF in post-BDG patients by saline contrast transesophageal echocardiography (TEE) and compare with pulmonary angiography and pulmonary vein oximetry. This was a prospective study done between 2017 and 2018. Twenty-five children who underwent BDG and planned for cardiac catheterization prior to Fontan completion were included in the study. All patients underwent pulmonary angiography, oximetry, and saline contrast TEE at the time of cardiac catheterization. Twenty-two patients had undergone unilateral BDG surgery and three were palliated by bilateral BDG. The mean oxygen saturation was 80 ± 5.2%. Thirteen patients (52%) had preserved antegrade pulmonary blood flow. Eighteen patients (72%) had PAVF by angiography and oximetry, while 19 (76%) had PAVF identified by contrast echocardiography. There was moderate correlation between the degree of pulmonary venous desaturation and grading of PAVF by contrast echocardiography. PAVF was predominantly located in the lower zones of the lungs. Higher grades of PAVF were not seen in patients with preserved antegrade flow after BDG. Angiographically detected PAVF showed a steady increase with increasing delay to cardiac catheterization from BDG. Significant reduction in systemic saturation was limited to advanced grades of PAVF in patients after BDG. Saline contrast TEE, pulmonary venous oximetry, and pulmonary angiography equally identified PAVF in patients after BDG. Prognostic utility of the same needs to be assessed by long-term follow-up of these subjects.

Management of a complicated 'pacemaker pocket' site infection.

Pocket site infection after implantation of a pacemaker is a dreaded complication which requires removing the device and reimplanting it at a contralateral site. Difficulties arise when the patient is dependent on pacing and when there are issues with venous access at the contralateral site. We report a patient with pacemaker pocket site infection with congenital complete heart block managed with explantation of the device, semi-permanent pacing during antibiotic treatment, reimplantation of the device at the contralateral site and management of subtotal subclavian vein stenosis noted during reimplantation.

Tachycardiomyopathy managed by successful ablation of right ventricular outflow tract premature ventricular complexes.

Tachycardiomyopathy is a common reversible cause of left ventricular dysfunction. Prompt diagnosis and treatment of this condition is essential to ensure a good prognosis for the patient. We report a case of tachycardiomyopathy due to frequent premature ventricular complexes arising from the right ventricular outflow tract midseptum managed with successful ablation.

Tricuspid annular PVCS: Radiofrequency ablation by subtricuspid retrograde catheter approach.

Tricuspid annular PVCs constitute 8% of idiopathic PVCs and 5% of RV PVCs. Although a rare entity to encounter in routine clinical practice, it can be a prime culprit behind major arrhythmic burden in few individuals. Electroanatomic approach with sub tricuspid retrograde catheter technique can target those annular PVCs and decrease the arrhythmia burden to normal or near normal range. Although procedural approach for parahisian PVCs requires a close look to avoid injury to native conduction system, TA PVCs are a real challenge due to inherent catheter instability and contact issue in sub tricuspid retrograde approach.

Clinical profile & long-term natural history of symptomatic coronary artery disease in young patients (<30 yr).

Background & objectives: Several studies have shown a high prevalence of cardiovascular risk factors in patients in the age group of 30-74 yr, but there is a paucity of data in young patients below 30 yr. We analyzed the clinical and coronary angiographic profile of patients <30 yr of age with symptomatic coronary artery disease (CAD) and also assessed their intermediate and long-term outcomes. Methods: All patients less than 30 yr of age who presented with symptomatic CAD from 1978 to 2017 in the department of Cardiology of a tertiary care hospital in south India, were studied for coronary risk factors and angiographic and treatment patterns, and the follow up data were collected. Results: The mean age of the 159 patients <30 yr of age was 26.7±3.29 yr. Male preponderance was observed (91.8%), 63.5 per cent patients were smokers and 88.3 per cent were dyslipidaemic. Acute myocardial infarction was the most common mode of presentation. Forty one per cent patients were non-adherent to medications. Risk factor control was inadequate with respect to smoking cessation, alcoholism, physical activity and dietary regulation. The predictors of long-term mortality were multivessel CAD [hazard ratio (HR): 1.927, 95% confidence interval (CI): 1.003-3.701] and reduction in ejection fraction (EF) (10% decrease in EF; HR: 1.349, 95% CI: 1.096-1.662). Overall mortality was 30 per cent at 10 yr and 48 per cent at 20 yr. Interpretation & conclusions: Decreasing EF and multivessel involvement were found to be the strong correlates for long-term mortality in young patients below 30 yr of age with CAD. High long-term mortality rates and poor risk factor control suggest the vast scope for the improvement of outcomes in these patients with aggressive risk factor control.

Response to atrial overdrive pacing during narrow QRS tachycardia. What is the mechanism?

A 35-year old lady with no pre-excitation on surface electrocardiogram underwent EP study for recurrent palpitation and documented adenosine responsive narrow QRS tachycardia. Regular narrow QRS tachycardia was induced with critical AH delay on programmed atrial stimulation. An atrial overdrive pacing (AOD) was performed during the tachycardia (Fig: 1 & 2). What is the response to AOD and what is the mechanism of tachycardia?

Interesting response to ventricular overdrive pacing during regular narrow QRS tachycardia. What is the mechanism?

33 year old gentleman has undergone an electrophysiology study for recurrent paroxysmal palpitation. During one of the episodes of palpitation a regular narrow QRS tachycardia was documented which has terminated with intravenous adenosine. Baseline electrocardiogram did not show any pre-excitation. Atrial-His (AH) and His-Ventricular (HV) intervals were normal at baseline. There was no evidence of dual atrioventricular (AV) nodal physiology. Earliest atrial electrogram during ventricular pacing was recorded at coronary sinus (CS) 9,10 dipoles placed at CS OS region. Narrow QRS tachycardia with cycle length (TCL) of 400 ms and earliest retrograde atrial activation at CS 9,10 dipoles was induced with programmed ventricular stimulation. Ventricular overdrive (VOD) pacing was performed at 30 ms shorter than TCL during the tachycardia (Fig: 1). What is the mechanism of tachycardia?

Response of narrow QRS tachycardia in a patient with surgical closure of atrial septal defect to atrial overdrive pacing: What is the mechanism?

A 57-year old woman who had pericardial patch closure of ostium secundum atrial septal defect (ASD) at the age of 23 years presented with shortness of breath. Her echocardiogram showed no residual ASD, good biventricular function and normal pulmonary artery pressures.

Interesting case of dual tachycardia in a patient with surgical closure of atrial septal defect.

A 34-year-old gentleman, who had undergone pericardial patch closure of ostium secundum atrial septal defect (ASD) at 8 years of age, was evaluated for shortness of breath. Electrocardiogram revealed typical atrial flutter with varying atrioventricular conduction. Echocardiogram showed no residual ASD or pulmonary hypertension and good biventricular function. He was taken for an electrophysiological study with the intention of radiofrequency ablation of the typical flutter.

Classical response of antidromic atriofascicular tachycardia to premature atrial extrastimulus delivered during septal refractoriness.

A 23-year-old gentleman presented with a history of palpitations. The 12-lead electrocardiogram showed no manifest ventricular pre-excitation. Echocardiogram was within normal limits. A retrograde study showed concentric activation of the atrium with decremental conduction. Atrial pacing from right atrial free wall showed progressive pre-excitation. No anterograde nodal duality was documented.

Interesting case of narrow QRS tachycardia. What is the mechanism?

A 67-year-old female presented with history of recurrent palpitations. During one of the episodes of palpitation, a narrow QRS tachycardia was recorded and it was reported to be terminated with intravenous adenosine. The 12-lead electrocardiogram (ECG) showed no manifest ventricular preexcitation. ECG was within normal limits. The patient underwent an electrophysiology study after informed consent. She was taking calcium channel blockers and that was stopped five half-lives prior to the procedure. As catheters were being placed, a narrow QRS tachycardia got induced. During the study, there was development of right bundle branch block during the tachycardia. What is the mechanism of the tachycardia?

The mysterious "double" arch.

A child with cyanosis and heart failure was noted to have two different vascular arches of similar caliber on echocardiography. A systematic analysis of the rhythm and flow patterns revealed the mysterious "double" arch.

Narrow QRS tachycardia with extreme rightward axis. What is the mechanism?

A 25 year old lady presented with palpitation to the emergency department. Her pulse rate was 210 beats per minute. She was hemodynamically stable with a blood pressure of 100/60 mm Hg. 12 lead surface electrocardiogram (ECG) was recorded during the presentation (Fig. 1) and rhythm strip (Fig. 2A) during administration of IV adenosine. What is the likely diagnosis?