Clinical profile and outcomes of semi-permanent pacing in a tertiary care institute in southern India.

BACKGROUND: Semi-permanent pacing (SPP) includes the placement of a permanent lead through the internal jugular vein and connection to a pulse generator on the skin outside the venous access site. AIM: To evaluate the clinical profile and outcomes of semi-permanent pacing in a tertiary care institute in Southern India. METHODS: This is a retrospective observational study. All patients admitted and requiring management with semi-permanent pacing from January 2017 to June 2020 were included. RESULTS: From January 2017 to June 2020, 20 patients underwent semi-permanent pacing (SPP) with a median age of 54 (21-74) years. Males comprised a majority of the patients (55%). Hypertension was noted in 50% of patients and 30% were diabetic. The right internal jugular vein was the most common access in 95% of patients. The most common indication for semi-permanent pacing was pocket site infection in 30% of patients. There were no procedural complications. The median duration on SPP was 7 (5-14) days and the median duration of hospital stay was 13 (8-21) days. Permanent pacemaker implantation was done in 55% of patients. Mortality in our study group was 15% with 10% dying due to cardiogenic shock (post resuscitated cardiac arrest) and 5% dying due to non-cardiac cause (Epidural hematoma). CONCLUSION: In our study, semi-permanent pacing was noted to be a safe procedure and was more commonly indicated in emergent conditions with complete heart block secondary to underlying reversible causes and in the management of pocket site infection.

Influence of age at surgery on left ventricular strain in patients with anomalous origin of left coronary artery from pulmonary artery.

OBJECTIVES: Myocardial strain abnormalities are described after surgical repair of anomalous left coronary artery from pulmonary artery (ALCAPA) even after recovery of ventricular function. The factors that predispose to the presence of these strain abnormalities in the presence of normal ventricular function are unknown. The aim of this study was to find out whether the age at repair influences the presence of global and regional strain abnormalities on follow-up. METHODS: Repaired ALCAPA patients from a single centre (n = 40) with good ventricular ejection fraction on follow-up were recruited. Baseline and follow-up data were collected from electronic records. Global and regional myocardial strain assessment was done by speckle tracking echocardiography prospectively. The association between age at repair and strain abnormalities on follow-up was analysed. RESULTS: The patients who presented earlier had significantly worse ventricular function pre-operatively compared to older patients (P < 0.0005). Global longitudinal strain was abnormal in 40% of patients with normal ventricular ejection fraction on follow-up. Presence of longitudinal strain abnormalities was more in patients who underwent repair at older age than in those who were repaired earlier (P < 0.0005). The probability of having normal longitudinal strain on follow-up was 81.6% if surgery was done before 7.8 months of age. If operated before 6 months, the odds of having normal myocardial strain was 11 times higher. Regional strain abnormalities of varying severity were present in all patients in the left and in some patients in the right coronary artery territories. CONCLUSIONS: Older age at ALCAPA repair is associated with increased incidence of myocardial strain abnormalities. Regional strain abnormalities were found in both left and right coronary artery territories.

Assessment of Lewis negative phenotype as a risk factor for multivessel disease in patients with acute coronary syndrome.

INTRODUCTION: Acute coronary syndrome is a manifestation of coronary artery disease caused by decreased blood flow to the heart musculature resulting in ischaemia and infarction of the heart. The Lewis (Le) blood group system comprise mainly Lewis a & b antigens which are secreted in plasma and are expressed on red cells, platelets and endothelium. This study assesses the risk of multivessel disease in acute coronary patients with lewis negative (a- b-) phenotype. MATERIALS AND METHODS: The study included 183 patients diagnosed with acute coronary syndrome and who underwent coronary angiography to detect stenosis of the coronary vessels. The severity of the disease was classified based upon the number of vessels stenosed and their blood sample was phenotyped for Lewis antigens. The patients' risk factors, GRACE score and management were included for the study and multivariate logistic regression was carried out for analysis. RESULTS: The prevalence of Lewis (a- b-) was 27.4% and there was a significant association with multivessel disease (P<0.05). However, there was no association of lewis (a- b-) with any of the risk factors causing coronary disease. The adjusted odds ratio of triple vessel disease in lewis (a- b-) was 2.6, female gender was 0.6 and patients with diabetes mellitus was 3.1, respectively. The GRACE score showed a significant association with ABO blood group (P<0.05) but not with lewis (a- b-). DISCUSSION: Lewis negative patients are more likely to develop triple vessel disease compared to other lewis blood groups. This warrants further studies to investigate the link between lewis system and atherothrombosis.

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.

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.

Mitral valve leaflet diverticulum with vegetation-a rare complication in rheumatic heart disease.

Diverticulum of mitral leaflet is a rare complication, which is recognized by its central clearing with characteristic diastolic collapse and systolic expansion on echocardiogram. It is found to be commonly associated with infective endocarditis while various other mechanisms of its formation have been suggested. The present case with an underlying history of rheumatic heart disease complicated by infective endocarditis well demonstrates the formation of mitral leaflet diverticulum and its possible complications. Surgical findings revealed diverticulum of the anterior mitral leaflet, and the patient underwent double valve replacement.

Re-entrant ventricular tachycardia in a postoperative case of tetralogy of Fallot - Ablated successfully under the three-dimensional mapping system.

A 47-year-old female underwent cardiac repair for tetralogy of Fallot at the age of 12 years. Subsequently, she was asymptomatic on follow-up. Recently, she presented elsewhere with palpitations and presyncope with documented ventricular tachycardia (VT) having left bundle branch block morphology with inferior QRS axis and late precordial transition. She was reported to have cardioverted and referred to our center for electrophysiology study (EP). She underwent EP study which induced clinical VT which was hemodynamically stable and the mechanism of VT was confirmed as re-entry. With the help of three-dimensional mapping system, VT circuit was identified in the posterior right ventricular outflow tract region between the pulmonary valve and upper end of ventricular septal defect patch. Delivery of radiofrequency energy during VT terminated the tachycardia with no further inducible VT despite aggressive pacing protocols.

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?

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.

Prognostic value of late gadolinium enhancement in cardiac MRI of non-ischemic dilated cardiomyopathy patients.

BACKGROUND: The role of late gadolinium enhancement (LGE) in cardiac MRI (CMR) as prognostic marker in non-ischemic dilated cardiomyopathy (NIDCM) is evolving. OBJECTIVE: To study the effect of LGE in the prognosis of NIDCM patients. METHODS: 112 consecutive NIDCM patients, who underwent CMR, were prospectively followed up for 745 ± 320 days. Primary end point was occurrence of MACE {composite of all-cause mortality, resuscitated cardiac arrest, sustained ventricular tachycardia (VT)/appropriate ICD shock, heart failure (HF) hospitalization}. RESULTS: LGE was present in 44 out of 112 patients (39%). The primary end point (MACE) was significantly higher in LGE + ve group compared to the LGE -ve group (72.7% vs. 29.4%; p < 0.0001). Similarly, cardiac mortality (9.1% vs 2.9%; p < 0.049), VT (13.6% vs. 2.9%; p < 0.031), HF hospitalization (63.6% vs. 30.9%; p < 0.001) were significantly more in LGE + ve group. In univariate model, LGE demonstrated the strongest association with MACE (Hazard ratio [HR] = 2.96 [95% CI 1.685 to 5.201; p < 0.0001). LGE extent of >14% of LV predicted MACE with 90.6% sensitivity and 86% specificity. HR of LGE extent >14% of LV for MACE is 6.12; p < 0.01. LGE was associated with MACE irrespective of its location, pattern or distribution. Multivariate model showed LGE and its extent >14% of LV volume were strongest predictor of MACE. CONCLUSION: LGE and its extent >14% predicts adverse cardiac events in NIDCM irrespective of LVEF and LGE location, pattern or distribution. This study emphasises the role of CMR in risk stratification of NIDCM patients and guiding therapy.

Immediate, early and mid-term outcomes following balloon mitral valvotomy in patients having severe rheumatic mitral stenosis with significant tricuspid regurgitation.

BACKGROUND: The study examined the influence of significant tricuspid regurgitation (TR) on the immediate, early and mid-term outcomes of patients with severe mitral stenosis (MS) undergoing balloon mitral valvotomy (BMV). METHODS: Among the 818 consecutive patients who underwent elective BMV in this institute from 1997 to 2003, 114 had significant TR. After propensity score-matched analysis, the data of 93 patients with significant TR were compared with the data of 93 patients who had no significant TR at the baseline. Outcomes were assessed immediately, at 1 year (early) and at 5 years (mid-term) after BMV. RESULTS: Patients with significant TR presented more frequently with NYHA class III-IV status, atrial fibrillation (AF), severe pulmonary hypertension (PH), advanced mitral valve disease as assessed by echocardiographic score > 8, and with history of previous BMV. After propensity score-matched analysis, it was found that the immediate procedural success (54.8% vs. 58.1%, P = 0.650), immediate in-hospital events and prevalence of AF and heart failure at 1 year of follow-up were comparable between the two groups. At 5 years after BMV, the significant TR group had higher prevalence of heart failure and AF, greater attrition in mitral valve area (MVA) and higher pulmonary artery (PA) pressure. CONCLUSIONS: Significant TR identifies a sicker patient population with MS. Even though patients with significant TR have comparable immediate and early outcomes after BMV, they have poor outcomes on mid-term follow-up. Longer follow-up with more patients is needed to assess survival aspect of TR on patients undergoing BMV and also to look at the need for interventions to address the significant TR, apart from the mitral valve interventions.

Wide and narrow QRS tachycardias: What is the mechanism?

A 50-year-old lady was referred for radiofrequency catheter ablation of narrow QRS tachycardia that was terminated with intravenous adenosine. Twelve-lead Electrocardiogram (ECG) was normal during sinus rhythm. The electrophysiological study showed an Atrio-Hisian (AH) interval of 104 ms and Hisio-Ventricular (HV) interval of 45 ms during sinus rhythm. Atrial pacing reproducibly induced regular broad (left bundle branch block morphology) and narrow QRS tachycardias. A spontaneous premature ventricular ectopic from right ventricular apex has resulted in transition of the tachycardia from wide to narrow. What are the likely mechanisms?