Magnetic resonance imaging in non-conditional pacemakers and implantable cardioverter-defibrillators: a systematic review and meta-analysis

AIMS: There is growing evidence that magnetic resonance imaging (MRI) scanning in patients with non-conditional cardiac implantable electronic devices (CIEDs) can be performed safely. Here, we aim to assess the safety of MRI in patients with non-conditional CIEDs. METHODS AND RESULTS: English scientific literature was searched using PubMed/Embase/CINAHL with keywords of 'magnetic resonance imaging', 'pacemaker', 'implantable defibrillator', and 'cardiac resynchronization therapy'. Studies assessing outcomes of adverse events or significant changes in CIED parameters after MRI scanning in patients with non-conditional CIEDs were included. References were excluded if the MRI conditionality of the CIEDs was undisclosed; number of patients enrolled was 0.5 V and impedance >50Ω was seen in 1.1% [95% confidence interval (CI) 0.7-1.8%] and 4.8% (95% CI 3.3-6.4%) respectively. The incidence of reduction in P- and R-wave sensing by >50% was 1.5% (95% CI 0.6-2.9%) and 0.4% (95% CI 0.06-1.1%), respectively. Battery voltage reduction of >0.04 V was reported in 2.2% (95% CI 0.2-6.1%). CONCLUSION: This meta-analysis affirms the safety of MR imaging in non-conditional CIEDs with no death or implantable cardioverter-defibrillator shocks and extremely low incidence of lead or device-related complications.Dian A. Munawar, Joel E.Z. Chan, Mehrdad Emami, Kadhim Kadhim, Kashif Khokhar, Catherine O’Shea ... et al

Implication of ventricular pacing burden and atrial pacing therapies on the progression of atrial fibrillation: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND:Atrial fibrillation (AF) is common after pacemaker implantation. However, the impact of pacemaker algorithms in AF prevention is not well understood. OBJECTIVE:The purpose of this study was to evaluate the role of pacing algorithms in preventing AF progression. METHODS:A systematic search of articles using the PubMed and Embase databases resulted in a total of 754 references. After exclusions, 21 randomized controlled trials (8336 patients) were analyzed, comprising studies reporting ventricular pacing percentage (VP%) (AAI vs DDD, n = 1; reducing ventricular pacing [RedVP] algorithms, n = 2); and atrial pacing therapies (atrial preference pacing [APP], n = 14; atrial antitachycardia pacing [aATP]+APP, n = 3; RedVP+APP+aATP, n = 1). RESULTS:Low VP% (10%). APP algorithm reduced premature atrial complexes (PAC) burden (mean difference [MD] -1117.74; 95% CI -1852.36 to -383.11; P = .003; I2 = 67%) but did not decrease AF burden (MD 8.20; 95% CI -5.39 to 21.80; P = .24; I2 = 17%) or AF episodes (MD 0.00; 95% CI -0.24 to 0.25; P = .98; I2 = 0%). Similarly, aATP+APP programming showed no significant difference in AF progression (odds ratio 0.65; 95% CI 0.36-1.14; P = .13; I2 = 61%). No serious adverse events related to algorithm were reported. CONCLUSION:This meta-analysis of randomized controlled trials demonstrated that algorithms to reduce VP% can be considered safe. Low burden VP% did not significantly suppress AF progression. The atrial pacing therapy algorithms could suppress PAC burden but did not prevent AF progression.Dian A. Munawar, Rajiv Mahajan, Thomas A. Agbaedeng, Anand Thiyagarajah, Darragh J. Twomey, Kashif Khokhar, Catherine O’Shea, Glenn D. Young, Kurt C. Roberts-Thomson, Muhammad Munawar, Dennis H.Lau, Prashanthan Sander

Meta-analysis of effects of epicardial fat on atrial fibrillation and ablation outcome

Abstract 354T. Agbaedeng, R. Mahajan, D. Munawar, A. Elliott, D. Twomey, S. Kurmar, D. Lau, P. Sander

Should We Check It? Assessing Interrogation of Cardiac Implantable Electronic Devices in the Emergency Department-The CHECK-ED Study: Implications for Service Planning and Care Delivery

Background: Requests from the emergency department (ED) for cardiac implantable electronic device (CIED) checks constitute a large workload for cardiac electrophysiology services. We sought to determine the yield of, and clinical characteristics associated with, clinically relevant (remarkable) issues from ED CIED checks. Methods Consecutive CIED checks from our ED over a 12-month period were studied. A remarkable issue (RI) was defined as arrhythmia relating to the presentation or device/lead issue requiring reprogramming or intervention. The association between the presenting complaint and an RI was assessed using regression analysis. Multivariable regression model was used to identify pre-specified patient-level characteristics that were predictive of a RI. Results: A RI was found in 28% (n=98) of 354 ED CIED checks for 306 patients (76616 yrs, 59% male). Most patients had no RI (n=224, 73%). One third of checks occurred after-hours and these had a higher yield of RIs than those during routine clinic hours (35% vs 23%, p=0.018). Presenting with a perceived ICD shock was predictive of a RI (odds ratio [OR] 6.0, 95% CI=1.8–20.0). Syncope/presyncope was five-fold less likely to be predictive of a RI (OR 0.19, 95% CI=0.13–0.28) despite being the most common indication for CIED check (51%, n=180 checks). Only history of AF was predictive of RI while advancing age was predictive of not finding a RI. Conclusion: Almost three-quarters of ED CIED checks did not yield any RI. Patient-reported ICD shock and history of AF were predictive of RI, while syncope/presyncope was not. New models of care especially during afterhours, may help to reduce the burden on cardiac electrophysiology services and health care costs.Bradley M. Pitman, Vincent Schirripa, Dian A. Munawar, Kadhim Kadhim, Catherine J. O, Shea, Ricardo S. Mishima, Kurt Roberts-Thomson, Glenn D. Young, M Christopher X. Wong, Prashanthan Sanders, Dennis H. La

Outcomes of persistent and long-standing persistent atrial fibrillation ablation: a systematic review and meta-analysis

Aims: Several techniques have been utilized for the ablation of persistent (P) and long-standing persistent (LsP) atrial fibrillation (AF); however, the best approach of substrate ablation remains poorly defined. This study aims to examine the impact of ablation approach on outcomes associated with P or LsP AF ablation by conducting a meta-analysis and regression on contemporary literature. Methods and Results: A systematic literature review was conducted up to 29 July 2015 for scientific literature reporting on outcomes associated with P or LsP AF ablation. One hundred and thirteen studies reported outcomes in a total of 18 657 patients undergoing various ablation approaches for the treatment of P-LsP AF between 2001 and 2015. The point efficacy estimate of a single-AF ablation procedure without the use of anti-arrhythmic drugs was 43% (95% CI; 39-47%). Multiple procedures and/or the use of anti-arrhythmic drugs increase success to 69% (95% CI; 66-71%). Meta-regression revealed that ablation technique (P < 0.001) and left atrial size (P = 0.02) were predictive of single procedure, drug-free success. The addition of extra-pulmonary substrate approaches was associated with declining efficacy when compared to a pulmonary vein ablation alone. Conclusion: The efficacy of a single-AF ablation procedure for P or LsP AF is 43%; however, can be increased to 69% with the use of multiple procedures and/or anti-arrhythmic drugs. Current literature supports the finding that pulmonary vein antrum ablation/isolation is at least equivalently efficacious to other contemporary P-LsP ablation strategies.Jock A. Clarnette, Anthony G. Brooks, Rajiv Mahajan, Adrian D. Elliott, Darragh J. Twomey, Rajeev K. Pathak, Sharath Kumar, Dian A. Munawar, Glenn D. Young, Jonathan M. Kalman, Dennis H. Lau, and Prashanthan Sander