The Syncope-Stopper study: comparison of the effectiveness and complications of upfront pacing with standard care for high-risk adult patients with unexplained syncope

Syncope-Stopper

Patient / Population Intervention / Exposition Comparaison Critère de jugement

In 200 older adults with high-risk unexplained syncope, upfront pacemaker implantation reduced cardiovascular death, recurrent syncope, bradycardia or device complications at 12 months compared with standard monitoring.

N

200patients

Schéma

Australian (Victoria) multicentre, prospective, open-label, 1:1 randomised controlled trial across six recruiting hospitals in metropolitan Melbourne; investigator-initiated, sponsored by Alfred Health with funding from Monash University and the National Heart Foundation, no commercial sponsor; age 55 years or older, at least one unexplained syncope in the preceding 12 months and a DROP score of 2 or more (distal conduction disease, no related historical precipitant, older age over 65, PR prolongation); excluded were an existing Class I device indication, likely neurocardiogenic/vasovagal aetiology (postural systolic fall over 30 mmHg, carotid sinus hypersensitivity, situational syncope), LVEF under 40%, prior pacemaker/ICD/loop recorder, contraindication to transvenous pacing and comorbidity precluding follow-up; upfront permanent pacemaker implanted by a cardiologist with pacing expertise versus standard care as directed by the treating team (Holter or implantable loop recorder); 12 months of follow-up.

Critère

12-month composite of recurrent syncope, bradycardia requiring pacemaker implantation, cardiovascular death, or device-related complication requiring re-intervention

Pertinence

2Important — l’un des piliers parmi d’autres.

RésultatThe composite occurred in 17.2% with upfront pacing and 31.7% with standard care (HR 0.49, 95% CI 0.27–0.87; P = 0.014). Recurrent syncope fell from 21.8% to 11.1% (11 of 99 vs 22 of 101; HR 0.47, 95% CI 0.23–0.97; P = 0.037, NNT 9.3), and bradycardia leading to a pacemaker occurred in 0% versus 18.8% (P < 0.001). Cardiovascular death was 3.0% in both arms and all-cause mortality 4.0% versus 3.0%. Major device complications were 3.0% versus 1.0% and minor complications 9.1% versus none. Emergency presentations were 24.2% versus 40.6% (P = 0.016), admissions 36.4% versus 63.4% (P < 0.001), and median admission days 0 versus 3.

William JB, Voskoboinik A, et al. Presented at ESC Congress 2026, Hot Line 10, 31 August.

Discussion et critique

Two of the four components of the composite are decided by the assignment itself: bradycardia leading to a pacemaker cannot occur in patients who already have one, and it supplied 19 of the standard-care events. Read the composite with that in mind and the trial still holds, because recurrent syncope halved on its own — 11.1% against 21.8%, with an NNT of 9 in patients averaging 80 years, two thirds of whom faint without warning and nearly half of whom had already been injured. The strategy is unblinded and small, mortality is unchanged, and 9% paid a minor device complication; what the DROP score buys is a pretest probability of bradyarrhythmia high enough that waiting to document it costs more than pacing without proof.