The use of non-invasive mapping in persistent AF to predict acute procedural outcome.

BACKGROUND: ECG imaging (ECGI) with phase mapping has been used to identify rotational activity non-invasively that can be targeted during atrial fibrillation (AF) ablation. Acute termination of AF using this method has shown improved clinical outcomes. In this study we sought to evaluate whether patterns of rotational density are associated with acute procedural outcomes when using a step-wise ablation strategy. METHODS: 50 patients with persistent or long-standing persistent AF underwent non-invasive 3D mapping with CardioInsight™ prior to AF ablation. Composite maps of rotational activity were created and prioritized based on the density of rotations on a biatrial model. Stepwise ablation of pulmonary vein isolation (PVI) ±â€¯rotations ± linear lesions was done with AF termination as the procedural endpoint. RESULTS: Acute termination of AF was achieved in 34 patients (68%). Median number of rotations in the left atrium (LA), interatrial septum and right atrium (RA) were 22.2 (9.4 to 29.3), 12.0 (4.3 to 13.4), 25.0 (14.5 to 31.3), respectively. In patients with acute AF termination, a higher number of rotations in the LA was observed, 20.3 (10.0 to 37.1) compared to 10.6 (7.7 to 17.2) in the RA (p = 0.02). Additionally, high density of rotations in the posterior inferior right atrium (segment 2B on the biatrial model) was observed in patients without acute AF termination (p = 0.02). CONCLUSION: Acute termination of persistent and long-standing persistent AF using rotational ablation guided by ECGI phase mapping can be achieved in a high percentage of both index and re-do cases. The distribution and pattern of these rotations may be associated with procedural outcomes and could potentially be used to stratify patients.

Developing home cleaning intervention through community engagement to reduce infections and antimicrobial resistance in Ghanaian homes.

Globally Antimicrobial Resistance (AMR) constitutes a health crisis, particularly in developing countries, where infectious disease are commonly fatal. There is clear evidence for microbial exposure and infection transmission within the home. Personal and environmental hygiene are the best ways of reducing household infections thus decreasing the need for antibiotics and consequently diminishing AMR. Despite this being an obvious step, research efforts to understand the home environment and its impact on AMR, cleaning and possible interventions on household cleaning are limited. We combined design and microbiology methods in an innovative mixed-method approach. A traditional survey design (n = 240), a design ethnography (n = 12), a co-design workshop and a pre-intervention microbiological dust sample analysis was undertaken to provide insights for codesign workshops in which new cleaning practices might be developed to minimise any AMR bacteria present in the household environments located in the Greater Accra Region of Ghana. Microbiological analysis of household dust showed that 36.6% of bacterial isolates detected were found to carry at least one resistance to the panel of antibiotics tested. Four scenarios were generated from an economic segmentation of the survey data. 50 ethnographic insights were 'presented' and descriptions of 12 bacteria species that showed resistance to one or more antibiotics (representing 176 bacterial isolates that showed resistance to one or more antibiotics found in the dust samples) were presented to the participants in a codesign workshop. An intervention, a new regime of cleaning practices agreed through the co-design workshop and practiced for thirty days, was made in (n = 7) households. The high prevalence of multidrug resistance observed in this study indicate the need for antibiotics surveillance program, not only in hospital settings but also in the household environment. There is, thus, an urgent need for targeting of interventions at the household level. Activating knowledge through community engagement in the research helps in increasing public perception and breaking down the scientist-public barrier.

Efficacy and safety of ventricular tachycardia ablation with mechanical circulatory support compared with substrate-based ablation techniques.

AIMS: Catheter ablation of ventricular tachycardia (VT) can be limited by haemodynamic instability. In these cases, substrate-based ablation is typically performed. An alternative is to perform activation and entrainment mapping during VT supported by a percutaneous left ventricular assist device (pVAD). We sought to compare the complication and success rates of pVAD-assisted VT ablation with scar-based techniques. METHODS AND RESULTS: Thirteen consecutive patients with haemodynamically unstable VT underwent pVAD-assisted ablation (pVAD group) and were retrospectively compared with 18-matched patients undergoing a substrate-based VT ablation (non-pVAD group). There was no significant difference in age or ejection fraction between the groups although pVAD patients tended to have more shocks in the preceding months. Procedure times were longer for the pVAD group. The number of monomorphic VTs induced was greater in the pVAD group (3.2 vs. 1.6, P= 0.04); however, after ablation, there was no difference in inducibility between the pVAD and non-pVAD group (10 of 13 vs. 12 of 18; 77 vs. 67%, P = 0.69). There was no difference in acute complications including stroke or death. At 9 ± 3 months, 1-year freedom from implantable cardioverter-defibrillator (ICD) shocks/therapies for sustained VT were similar (P= 0.96). In multivariable analysis, the absence of atrial fibrillation (hazard ratio=0.15, P= 0.04) was associated with a lower incidence of ICD shocks. CONCLUSIONS: In high-risk patients, pVAD-assisted VT ablation guided by activation and entrainment mapping is a feasible alternative to substrate mapping and allows outcomes comparable to substrate mapping.