Michele Brignole1, Jean Claude Deharo2, Carlo Menozzi3, Angel Moya4, Richard Sutton5, Marco Tomaino6, Andrea Ungar7. 1. Department of Cardiology, Arrhythmologic Centre, Ospedali del Tigullio, Via Don Bobbio 25, Lavagna, Italy. 2. Department of Cardiology, Hopital La Timone Adultes, 264 Rue Saint-Pierre, Marseille cedex 5, France. 3. Department of Cardiology, Arcispedale S. Maria Nuova, Viale Risorgimento 80, Reggio Emilia, Italy. 4. Department of Cardiology, Hospital Universitario Vall d'Hebron, Paseo valle d'Ebron 119-129, Barcelona, Spain. 5. Department of Cardiology, National Heart and Lung Institute, Imperial College, South Kensington Campus, London, UK. 6. Department of Cardiology, Ospedale di Bolzano, Via Lorenz Bohler 5, Bolzano, Italy. 7. Department of Cardiology, University of Florence, AOU Careggi, Viale Pieraccini 6, Florence, Italy.
Abstract
Aim: Although the efficacy of cardiac pacing in patients with neurally mediated syncope (NMS) and documented asystole is established, a more robust point estimate of the benefit, which is not possible with any individual study, is lacking. Methods and results: We undertook a meta-analysis of individual participant data from four studies that reported follow-up data on syncope recurrence with cardiac pacing in patients with NMS who had had an electrocardiographic (ECG) documentation of an asystolic event by means of implantable loop recorder (ILR). Of a total of 1046 patients, who had ILR implanted, 383 (36.6%) patients had an ECG documentation of a diagnostic event during mean follow-up of 13 ± 10 months. Of these, 201 (52%) patients, corresponding to 19.2% of the total ILRs, had an asystolic event of 12.8 ± 11.0 s duration documented and met the criteria for pacemaker therapy. Follow-up was available in 121 (60%) of those patients with asystolic events. Syncope recurred after pacing in 18 (14.9%) patients with an actuarial rate of 13% [95% confidence interval (CI) ±6] at 1 year, 21% (95%CI ±10) at 2 years, and 24% (95%CI ±11) at 3 years. On multivariable Cox regression analysis, positive tilt test response was the only significant predictor of syncope recurrence with a hazard ratio (95% CI) of 4.3 (1.4-13). On the contrary, type of asystolic event (sinus arrest or atrioventricular block), prodrome, cardiac abnormalities, number and duration of history of syncope, age, and gender were not predictors of recurrence of syncope. Conclusion: A long asystolic pause, suitable for pacemaker therapy, was found in one of five patients with ILR. After pacemaker implantation, most of these patients remained free of syncope recurrence for up to 3 years. The benefit of pacemaker was greater in patients with negative tilt test.
Aim: Although the efficacy of cardiac pacing in patients with neurally mediated syncope (NMS) and documented asystole is established, a more robust point estimate of the benefit, which is not possible with any individual study, is lacking. Methods and results: We undertook a meta-analysis of individual participant data from four studies that reported follow-up data on syncope recurrence with cardiac pacing in patients with NMS who had had an electrocardiographic (ECG) documentation of an asystolic event by means of implantable loop recorder (ILR). Of a total of 1046 patients, who had ILR implanted, 383 (36.6%) patients had an ECG documentation of a diagnostic event during mean follow-up of 13 ± 10 months. Of these, 201 (52%) patients, corresponding to 19.2% of the total ILRs, had an asystolic event of 12.8 ± 11.0 s duration documented and met the criteria for pacemaker therapy. Follow-up was available in 121 (60%) of those patients with asystolic events. Syncope recurred after pacing in 18 (14.9%) patients with an actuarial rate of 13% [95% confidence interval (CI) ±6] at 1 year, 21% (95%CI ±10) at 2 years, and 24% (95%CI ±11) at 3 years. On multivariable Cox regression analysis, positive tilt test response was the only significant predictor of syncope recurrence with a hazard ratio (95% CI) of 4.3 (1.4-13). On the contrary, type of asystolic event (sinus arrest or atrioventricular block), prodrome, cardiac abnormalities, number and duration of history of syncope, age, and gender were not predictors of recurrence of syncope. Conclusion:A long asystolic pause, suitable for pacemaker therapy, was found in one of five patients with ILR. After pacemaker implantation, most of these patients remained free of syncope recurrence for up to 3 years. The benefit of pacemaker was greater in patients with negative tilt test.
Authors: Richard Sutton; Jelle S Y de Jong; Julian M Stewart; Artur Fedorowski; Frederik J de Lange Journal: Heart Rhythm Date: 2020-02-06 Impact factor: 6.343