Central Venous Catheter induced Atrial Fibrillation-A Case Report

Though a common procedure, central venous access is related to morbidity and mortality of patients. Common cardiac complications caused by central venous catheters include premature atrial and ventricular contractions. But development of atrial fibrillation with haemodynamic instability is quite rare. We are reporting a patient who developed atrial fibrillation with hypotension while inserting central venous catheter through right subclavian vein by landmark technique. Patient was managed with DC cardioversion. Careful insertion of central venous catheter & prompt management of its complication is crucial to avoid catastrophe. J Bangladesh Coll Phys Surg 2021; 39(3): 200-204

Efficacy and safety of hybrid convergent procedure vs endocardial catheter ablation for the management of atrial fibrillation

Funding Acknowledgements Type of funding sources: None. Background- Little is known regarding the efficacy and safety of hybrid convergent epicardial and endocardial approach (CVP) that has emerged as an alternative to endocardial catheter ablation (CA) for the management of persistent and paroxysmal atrial fibrillation. Methods-Electronic databases ( PubMed, Embase, Scopus) were searched from inception to Jan 6th, 2020. Unadjusted odds ratios (OR) were calculated from dichotomous data using Mantel Haenszel (M-H) random-effects with statistical significance to be considered if the confidence interval excludes 1 and p < 0.05. The primary outcome of interest was recurrence of atrial tachyarrhythmia {Atrial fibrillation (AF)/Atrial flutter(AFL) /Atrial tachycardia(AT)} Secondary outcomes included any intervention (DC Cardioversion (DCCV), repeat ablation) and major adverse events (MAE). Results- A total of three studies with 336 (CVP = 190, CA = 146) participants were included. CVP was associated with significantly higher freedom from atrial tachyarrhythmia recurrence compared with CA therapy (RR 0.60, 95% CI 0.45-0.78; p = 0.0002; I2 = 0). Patients receiving CVP had lower odds of requiring any re-intervention (DCCV, repeat ablation) when compared to CA therapy (RR 4.11, 95% CI 1.17-14.46; p = 0.03; I2 = 0). However, CVP was associated with significantly higher rate of major adverse events (RR 0.44, 95% CI 0.30-0.65; p= <0.0001; I2 = 0). Conclusion-Treatment with Hybrid convergent ablation seems to be superior than endocardial catheter ablation for prevention of arrhythmia recurrence but may also cause more severe adverse effects. Abstract Figure.

Anti-arrhythmic drugs confer increased risks of bradyarrhythmia in patients undergoing direct current cardioversion for atrial fibrillation

Background Bradyarrhythmia is a known complication to direct current cardioversion (DC-cardioversion) in patients with atrial fibrillation (AF). However, whether concomitant treatment with anti-arrhythmic drugs (AADs) is associated with an increased risk of bradyarrhythmia in relation to the procedure is unknown. Purpose To investigate the short-term risk of bradyarrhythmia associated with AAD treatment in AF patients undergoing DC-cardioversion. Methods Using Danish nationwide registers, all AF patients treated with either an AAD (amiodarone, sotalol, dronedarone, flecainide, or propafenone) or rate-lowering drugs (beta-blocker, non- dihydropyridine calcium-antagonist, or digoxin) were identified at their first DC-cardioversion between 2001 and 2016. Patients were excluded if they were under 18 or above 100 years of age or had a pacemaker or implantable cardioverter defibrillator. The event of interest was a composite outcome of either a diagnosis of bradyarrhythmia (sinoatrial arrest, atrioventricular block, or unspecified bradycardia) or a procedure of pacemaker implantation. Patients were followed from the date of DC-cardioversion until event of interest, 90 days after the procedure, or at study end. Absolute risks of bradyarrhythmic events were estimated using the Aalen-Johansen estimator taking the competing risk of death into account. Hazard ratios (HR) with 95% confidence intervals (95% CI) of bradyarrhythmic events were computed using multivariable Cox models adjusted for age, sex, calendar year, as well as relevant comorbidity and concomitant medication. Results A total of 22,344 patients were included in the study with 3,224 (14%) individuals treated with an AAD. The median age was 67 years (interquartile range [IQR] 59–73) and most were males (69%). Patients treated with AADs were younger and had more ischemic heart disease, heart failure, and valvular disease. During follow-up we identified 601 cases of bradyarrhythmia. We found an absolute risk of bradyarrhythmic events at 90 days after cardioversion of 3.7% (95% CI 3.1–4.4) for patients treated with an AAD and 2.5% (95% CI 2.3–2.7) for patients treated with rate-lowering drugs (P<0.001) (Figure 1). AAD treatment conferred increased rates of bradyarrhythmia with a multivariable adjusted HR of 1.35 (95% CI: 1.10–1.65) compared to patients treated with rate-lowering drugs. Conclusion Using a large nationwide study population of patients with AF undergoing DC-cardioversion, concomitant treatment with AADs was associated with an increased risk of bradyarrhythmic events. Moreover, the absolute risks of bradyarrhythmic events after DC-cardioversion were higher than what has previously been reported. These data provide valuable insights aiding physicians in clinical decision making as well as informing patients prior to the procedure. Figure 1. Absolute risk and adjusted hazard ratio (HR) of bradyarrythmia. AAD: Anti-arrhythmic drugs. CI: Confidence Interval. Funding Acknowledgement Type of funding source: None

The shocking lack of significant increases in high sensitivity troponin values after cardioversion

Background and introduction Cardioversion is commonly used to terminate cardiac arrhythmias. Some previous reports have suggested that cardioversion results in myocardial injury as evidenced by increased levels of cardiac troponin. However, many of these studies were done years ago with less sensitive troponin assays and monophasic waveform defibrillators. Purpose To determine if external direct current (DC) cardioversion with biphasic rectilinear waveform shocks results in myocardial injury as assessed by high sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI). Methods Patients scheduled for elective DC cardioversion for atrial fibrillation or atrial flutter were recruited. Plasma samples for measurement of hs-cTnT and hs-cTnI were obtained pre-cardioversion and as late as feasible but at least 6 hours post-cardioversion [median of 9 (7–11) hours]. Results A total of 96 patients were recruited. One patient was excluded because the pre-cardioversion sample was hemolysed. Median (25th–75th interquartile range) cumulative energy delivered was 121.6J (62.4–277.4J) and median highest energy individual shock was 121.0J (62.1–146.2J). A total of 39 (41.1%) patients received more than 1 shock, 23 (24.2%) patients received a cumulative energy of 300J or higher and 5 (5.3%) patients received a cumulative energy of 1,000J or more. The median pre-cardioversion hs-cTnT value was 11.48 (7.19–18.38) ng/L and the median hs-cTnI value was 5.1 (2.0–9.4) ng/L. Median post-cardioversion hs-cTnT value were 12.46 (7.98–20.28) ng/L and hs-cTnI value were 6.3 (3.5–10.0) ng/L. Wilcoxon-Signed ranks test showed a statistically significant change between the pre-and-post cardioversion hs-cTnT values (Z=−4.237, p<0.001) and hs-cTnI values (Z=−4.822, p<0.001). In only 5 (hs-cTnT) and 4 patients (hs-cTnI) was there an increase of >5 ng/L. There were 5 cases where the post-cardioversion values of both hs-cTnT and hs-cTnI were above the 50% reference change value. There was no relation between the change in hs-cTn values and sex, number of shocks, total energy delivered (even in those who received more than 1,000J), highest energy per shock, total current delivered, highest current delivered per shock or transthoracic impedance. Conclusion(s) There is a statistically significant but very small change in median hs-cTnT and hs-cTnI values (1 ng/L and 1.2 ng/L respectively) after DC cardioversion. The results were similar even in patients where high energy shocks were delivered and did not vary based on the pre cardioversion baseline value. Patients who have marked troponin elevations after cardioversion should be assessed for other causes of myocardial injury. It should not be assumed that they have myocardial injury from the cardioversion alone. Figure 1 Funding Acknowledgement Type of funding source: Other. Main funding source(s): Dr. Allan Jaffe has substantial research funds from both grants and private industry. Funds were used to pay for blood sample collection and analysis of high sensitivity cardiac troponin T at Mayo Clinic. Abbott Laboratories donated reagents for the high sensitivity cardiac troponin I analysis.

P1530 Dense spontaneous echo contrast and thrombus in patients on new oral anticoagulant and warfarin therapy: a retrospective audit

Background Cardioembolic stroke is a known complication of atrial fibrillation (AF), which is increasing in global prevalence. Spontaneous echo contrast (SEC) in the left atrium (LA) is a precursor for thrombus formation detected on transesophageal echocardiography (TEE). There is limited data regarding the prevalence of dense SEC and/or left atrial thrombus (LAT) detected by TEE in patients on novel oral anticoagulants (NOACs) compared with Warfarin. Purpose To determine and compare the prevalence of dense SEC and/or LAT among patients with AF/atrial flutter undergoing TEE while on continuous NOAC or Warfarin therapy. Methods Retrospective analysis of prospectively entered data for all patients who were on continuous oral anticoagulants and underwent TEE with DC cardioversion, over a 9-year period (1st January 2011 to 31st December 2018) at a public teaching hospital in NSW, Australia. SEC was classified according to emptying flow velocities, as per the European Association of Cardiovascular Imaging guidelines. Results Among the 195 patients, 94 (48%) patients were on NOAC therapy (52% Apixaban, 25% Rivaroxaban, 23% Dabigatran) while 101 (52%) patients were on Warfarin. There was no difference in age (mean ± SD: 64 ± 12 vs. 65 ± 13, p = 0.71) or proportion of males (71% vs 69%, p = 0.76) between patients on NOAC therapy compared with Warfarin. However, the NOAC therapy group had a lower prevalence of ischaemic heart disease (IHD) (18% vs. 33%, p < 0.05) and chronic kidney disease (CKD) (2% vs. 19%, p < 0.001), in addition to a lower CHA2DS2-VASc score (2.1 ± 1.7 vs 2.7 ± 1.7, p = 0.03) and higher haemoglobin levels (145.3 ± 19 vs 133.8 ± 24, p = 0.001). The overall rate of dense SEC and/or LAT detected by TEE was 9.7%. There was no significant difference in the prevalence of dense SEC and/or LAT between patients on NOACs and Warfarin (6.4% vs. 12.9%, p = 0.13). On multivariable analysis of IHD, CKD, Warfarin, NOACs and CHA2DS2-VASc score, there was no significant difference in prevalence of SEC/LAT between Warfarin and NOACs. Conclusions In this study, 6.4% of patients on continuous NOACs and 12.9% of patients on Warfarin therapy had dense SEC and/or LAT detected by TEE. Although the trend towards higher rates of dense SEC and pre-thrombus in the Warfarin group did not reach statistical significance, it still holds clinical significance as these patients cannot be cardioverted. Therefore, these data support the need to consider anticoagulant optimisation in the overall management of patients with SEC.

Endomyocardial fibrosis presented by ventricular tachycardia: case report

Background Endomyocardial fibrosis (EMF) is a form of restrictive cardiomyopathy that is diagnosed mainly in children and young adults and is geographically found in Africa, Latin America, and Asia. It is a condition with high morbidity and mortality, unknown etiology, and no definitive treatment. Although its main clinical presentation is congestive heart failure with or without related supraventricular arrhythmia like atrial fibrillation, it very rarely presents with ventricular arrhythmias and tachycardias (VA, VT). Case presentation We report a case of right ventricular (RV) EMF presented with recurrent attacks of hemodynamically unstable VT that required direct current (DC) cardioversion. The diagnosis was suspected by transthoracic echocardiography (TTE) and established by cardiac magnetic resonance (CMR). The patient underwent implantable cardioverter–defibrillator (ICD) implantation for secondary prevention of VT, and he was discharged safely on antiarrhythmic drugs with regular follow-up visits. Conclusion EMF presenting with VT are quite rare and to the best of our knowledge, our case is the fourth case in the literature to report VT as a clinical presentation of EMF.

Catheter ablation for atrial fibrillation is associated with lower incidence of heart failure and death

Aims Catheter ablation for atrial fibrillation (CAF) improves symptoms, but whether CAF improves outcome is less clear. The purpose of this study was to investigate whether CAF is associated with improved outcome in atrial fibrillation (AF) patients with previous direct current (DC) cardioversion. Methods and results We performed a nationwide cohort study including all patients who underwent their 1st direct current cardioversion for AF in the period 2003–15 (N = 25 439). End points were all-cause death, cardiovascular death, stroke/thromboembolism, and incident heart failure (HF). Catheter ablation for AF was treated as a time-varying covariate and the association with outcome was assessed using Cox regression. We also constructed a propensity-matched cohort and assessed the association between CAF and outcome. Median follow-up was 5.3 years (inter-quartile range 3.0–8.7 years). A total of 3509 patients (13.8%) underwent CAF during the study period. Following adjustment for age, gender, comorbidities, medications, educational level, household income, and CHA2DS2VASc score, CAF was associated with reduced risks of all-cause death, cardiovascular death, and incident HF [all-cause death: hazard ratio (HR) 0.69, P < 0.001; cardiovascular death: HR 0.68, P = 0.003; incident HF: HR 0.76, P = 0.011]. Catheter ablation for AF was not associated with a reduced risk of stroke/thromboembolism. These results were replicated in a propensity-matched cohort. Conclusion In AF patients with a prior DC cardioversion, CAF was associated with a reduced risk of all-cause and cardiovascular death. This may be due to a reduced risk of HF.