Incremental value of continuous non-invasive blood pressure control to assess hypotension during atrial fibrillation ablation

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. INTRODUCTION: Atrial Fibrillation (AF) ablation is associated with continuous blood pressure (BP) variations related to anesthesiological regimen and energy delivery. Conventional BP monitoring with non-invasive periodic brachial BP controls can miss potential hypotensive events. Continuous non-invasive blood pressure (CNBP) measurement using the volume-clamp method (Clearsight) was demonstrated to be a reliable and effective tool for the assessment of BP during AF ablation. PURPOSE: Aim of the study was to investigate the incidence of hypotensive events during AF ablation. METHODS: We included consecutive patients scheduled for AF ablation and monitored in parallel with a periodic (10 minutes) brachial BP cuff and in continuous with the CNBP System (Clearsight). All CNBP data were analyzed with the Acumen Analytics software for hypotension evaluation. According to the anesthesiological regimen, patients were divided in 2 Groups, the General Anesthesia (GA) and the Deep Sedation (DS) group. Area under the threshold (AUT, mmHg x min) of 65 mmHg and Time Weighted Average (TWA, mmHg, i.e., the AUT divided by the total duration of procedure in minutes) of area under threshold (MAP <65 mmHg) were compared between the two groups. RESULTS: Forty-eight patients were included, 10 (21%) in the General Anesthesia Group and 38 (79%) in the Sedation Group. Hypotension was detected in 18 patients, 9/10 (90%) were recorded in the GA group and 9/38 (23.7%) in the DS one. A total of 85 hypotensive events were recorded, 68 (80%) in the GA and 17 (20%) in the DS Group. In the overall population, mean duration of hypotensive events was 4.87 minutes (range 0 – 14.73 minutes), mean MAP < 65 mmHg was 54.25 ± 7.2 mmHg, mean AUT (MAP <65 mmHg) was 79.4 mmHg x min (range 0 – 1237.7) and mean TWA was 0.41 mmHg (range 0 – 6.9). Hypotensions were more often documented in GA than in DS patients (mean difference 6.35 events/procedure, C.I. 2.66 – 10.10, p<0.05) so as AUTs (mean difference 319.90 mmHg x min, C.I. 30.00 – 609.80, p=0.034) and TWAs (mean difference 1.64 mmHg, C.I. 0.18 – 3.09, p=0.032) which were significantly higher in the GA group. Brachial periodic BP measurement every 10 minutes missed the majority (n=52, 61.2%) of hypotensive events. CONCLUSIONS: CNBP demonstrated a high incidence of hypotension during AF ablation, specially under GA, which are usually missed by the standard intermittent brachial non-invasive BP monitoring. Real time hypotension predictive CNBP indexes could be valuable in this setting. [Figure: see text] [Figure: see text]