The benefit of cardioneuroablation to reduce syncope recurrence in vasovagal syncope patients: a case-control study.

BACKGROUND: Adequate and effective therapy for resistant vasovagal syncope patients is lacking and the benefit of cardioneuroablation (CNA) in this cohort is still debated. The aim of this study is to assess the long-term effect of CNA versus conservative therapy (CT) in a retrospectively followed cohort. METHODS: A total of 2874 patients underwent head-up tilt test (HUT) and 554 (19.2 %) were reported as positive, with VASIS type 2B response or > 3 s asystole in 130 patients. After exclusion of 29 patients under 18 years and over 65 years of age, 101 patients were included final analysis. Fifty-one patients (50.4%) underwent CNA and 50 (49.6%) patients received CT. After propensity score matching, 19 pairs of patients were successfully matched. The recurrence rate of syncope was compared between groups. RESULTS: During a median follow-up of 22 months (IQR, 13-35), syncope was seen in 12 (11.8%) cases. In the 19 propensity-matched patients, recurrent syncope was observed in 8 patients in the CT group and in 2 patients in the CNA group, respectively. In mixed effect Cox regression analysis, CNA was associated with less syncope recurrence risk at follow-up (HR 0.23, 95% CI 0.03-0.99, p = 0.049). The 4-year Kaplan-Meier syncope free rate was 0.86 (95% CI, 0.63-1.00) for CNA group and 0.50 (95% CI, 0.30-0.82) for CT group in the matched cohort. CONCLUSIONS: In highly selected patients with HUT-induced cardioinhibitory response, CNA is associated with a significant reduction in syncope recurrence during follow-up when compared to CT.

Safety and Efficacy of Ibutilide for Acute Pharmacological Cardioversion of Rheumatic Atrial Fibrillation.

INTRODUCTION: Ibutilide is indicated for acute cardioversion of nonvalvular atrial fibrillation (AF). However, its efficacy and safety in the pharmacological cardioversion of rheumatic AF are unknown. METHODS: Patients with mild-to-moderate rheumatic mitral valve (MV) disease with symptomatic, paroxysmal, or persistent AF were included in the analysis. Intravenous ibutilide was administered at doses tailored to body weight (0.5-2.0 mg) for over 10 min. The primary end point was efficacy, assessed as the rate of conversion of AF to sinus rhythm. The secondary end point was safety, including arrhythmic events and death within 24 h of drug initiation. RESULTS: From June 2016 to October 2018, 165 patients (94 with mitral stenosis, 23 with mitral regurgitation, 11 with mixed MV disease, and 37 with MV replacement) received ibutilide (mean dose 0.90 ± 0.54 mg). Ibutilide successfully converted AF to sinus rhythm in 127/165 (76.9%) patients, with a conversion time of 7.9 ± 4.1 min. The QTc increased from 419.9 ± 15.8 to 487.5 ± 34 ms after ibutilide administration (p < 0.001). The mean change in QTc after ibutilide administration (∆QTc) was 72.01 ± 36.03. There were no deaths, but 3 patients (1.8%) developed torsades de pointes (TdP) requiring defibrillation 55 ± 37 min after infusion. CONCLUSION: Ibutilide cardioverted 77% of rheumatic AF to sinus rhythm, indicating its potential as a clinically useful option for pharmacological cardioversion of rheumatic AF. TdP is a potentially serious adverse event that requires careful monitoring.

Clinical and Electrophysiological Correlates of Incessant Ivabradine-Sensitive Atrial Tachycardia.

BACKGROUND: Incessant focal atrial tachycardia (FAT), if untreated, can lead to ventricular dysfunction and heart failure (tachycardia-induced cardiomyopathy). Drug therapy of FAT is often difficult and ineffective. The efficacy of ivabradine has not been systematically evaluated in the treatment of FAT. METHODS: The study group consisted of patients with incessant FAT (lasting >24 hours) and structurally normal hearts. Patients with ventricular dysfunction as a consequence of FAT were not excluded. All antiarrhythmic drugs were discontinued at least 5 half-lives before the initiation of ivabradine. Oral ivabradine (adults, 10 mg twice 12 hours apart; pediatric patients: 0.28 mg/kg in 2 divided doses) was initiated in the intensive care unit under continuous electrocardiographic monitoring. A positive response was defined as the termination of tachycardia with the restoration of sinus rhythm or suppression of the tachycardia to <100 beats per minute without termination within 12 hours of initiating ivabradine. RESULTS: Twenty-eight patients (mean age, 34.6±21.5 years; women, 60.7%) were included in the study. The most common symptom was palpitation (85.7%) followed by shortness of breath (25%). The mean atrial rate during tachycardia was 170±21 beats per minute, and the mean left ventricular ejection fraction was 54.7±14.3%. Overall, 18 (64.3%) patients responded within 6 hours of the first dose of ivabradine. Thirteen of 18 ivabradine responders subsequently underwent successful catheter ablation. FAT originating in the atrial appendages was a predictor of ivabradine response compared with those arising from other atrial sites (P=0.046). CONCLUSIONS: Ivabradine-sensitive atrial tachycardia constitutes 64% of incessant FAT in patients without structural heart disease. Incessant FAT originating in the atrial appendages is more likely to respond to ivabradine than that arising from other atrial sites. Our findings implicate the funny current in the pathogenesis of FAT.

Remote ischemic preconditioning for prevention of contrast induced nephropathy-Insights from an Indian study.

OBJECTIVES: To study if four cycles of remote ischemic preconditioning (RIPC) could offer protection against contrast induced nephropathy (CIN) and post procedural renal dysfunction in high risk patients undergoing percutaneous coronary intervention (PCI). METHODS: This was a prospective single blind randomized sham controlled trial where patients undergoing coronary angioplasty with stage III chronic kidney disease were randomized into sham preconditioning and remote ischemic preconditioning. The primary outcome was the reduction in the incidence of CIN. The secondary outcomes were the maximum improvement in eGFR, maximum reduction in serum creatinine and composite of requirement of hemodialysis, death and rehospitalization for heart failure up to 6 weeks after PCI. RESULTS: Eleven out of fifty patients in the study group developed CIN (22%) compared to eighteen out of the fifty control patients (36%) (p=0.123). There was a statistically significant improvement in the post procedure creatinine values at 24h (p=0.013), 48h (p=0.015), 2 weeks (p=0.003), 6 weeks (p=0.003) and post procedure glomerular filtration rate (eGFR) values at 24h (p=0.026), 48h (p=0.044), 2 weeks (p=0.015) and 6 weeks (p=0.011) in study group compared to control group. The secondary outcome composite of requirement of hemodialysis, death and rehospitalization for heart failure was not statistically significant (p: 0.646). CONCLUSION: RIPC does not result in significant reduction of CIN. However RIPC helps in the prevention of post procedural worsening in eGFR and serum creatinine even up to 6 weeks.

Coronary angioplasty in spontaneous coronary artery dissection-Strategy and outcomes.

OBJECTIVE: To study the clinical, angiographic and technical characteristics of patients with spontaneous coronary artery dissection (SCAD) undergoing percutaneous coronary intervention (PCI). METHODS: This was a retrospective single center study where patients with angiographically confirmed SCAD undergoing PCI over a period of 4 years (2013-2017) were analyzed. We also sought to identify the clinical and angiographic predictors of procedural failure during PCI. RESULTS: There were a total of 42 patients with angiographically confirmed SCAD during the study period of which 16 patients (38.1%) underwent PCI. 14 out of the 16 patients (87.5%) taken up for PCI had technical success. In all patients the lesion was initially attempted to cross with a floppy wire and if unsuccessful it was escalated to a hydrophilic wire and finally to a stiff wire The SCAD lesion was crossed with a floppy wire in 71.4% of patients, with a hydrophilic wire in 14.2% and a stiff wire in 7.1% of patients. Wire escalation was required in 5 patients (31.3%) and in 60% of cases there was a technical success after wire escalation. Presence of diabetes mellitus, hypertension, dyslipidemia, smoking, coexisting atherosclerosis, diffuse nature of the lesion, and baseline Thrombolysis in Myocardial Infarction (TIMI)≤2 flow did not predict procedural failure during PCI. CONCLUSION: PCI in SCAD is associated with a fair rate of technical success in our population. Choosing an initial floppy wire and then escalating to a hydrophilic wire followed by a stiff wire is an optimal revascularization strategy.

Predictors of contrast induced nephropathy and the applicability of the Mehran risk score in high risk patients undergoing coronary angioplasty-A study from a tertiary care center in South India.

OBJECTIVE: To study the incidence and predictors of Contrast induced nephropathy (CIN) in high risk patients undergoing coronary angioplasty. To study the applicability of the Mehran Risk Score (MRS) in the prediction of CIN in our population. METHODS: This was a prospective observational study where patients with an estimated glomerular filtration rate (eGFR) between 30 and 60ml/mt undergoing elective percutaneous coronary intervention (PCI) over a period of 15 months were evaluated prospectively for the development of CIN. The patients who developed CIN were then analysed for the presence of specific risk factors. The patients were categorized into the 4 risk groups based on the MRS. RESULTS: 100 high risk patients underwent PCI during the study period. The incidence of CIN was 29%. On multivariate analysis, the presence of anemia (p=0.007), increased contrast volume usage (as defined by >5* B.Wt/S.cr) (p=0.012) and usage of loop diuretics (p=0.033) were independently found to confer a significant risk of CIN. In patients belonging to the high Mehran risk group (MRS10- 15) and very high risk group (MRS >15) the risk of CIN was 3 fold (OR: 3.055, 95% CI: 1.18-7.94, p=0.022) and 24 fold (OR: 24, 95% CI: 2.53-228.28, p=0.006) higher respectively when compared to intermediate and low risk patients (MRS <10). CONCLUSION: The incidence of CIN in high risk patients undergoing PCI is substantially higher in our population compared to similar studies in the west. The MRS risk prediction is pertinent even in an Indian population.