Dual-Chamber Pacing in the Treatment of Neurally Mediated Tilt-Positive Cardioinhibitory Syncope

Abstract

Background-This study was performed to compare implantation of a DDI pacemaker with rate hysteresis with no implant in respect to syncopal recurrences in patients with severe cardioinhibitory tilt-positive neurally mediated syncope. Methods and Results-Forty-two patients from 18 European centers were randomized to receive a DDI pacemaker programmed to 80 bpm with hysteresis of 45 bpm (19 patients) or no pacemaker (23 patients). Inclusion criteria were Ն3 syncopes over the last 2 years and a positive cardioinhibitory (Vasovagal Syncope International Study types 2A and 2B) response to tilt testing. The median number of previous syncopal episodes was 6; asystolic response to tilt testing was present in 36 patients (86%) (mean asystole, 13.9Ϯ10.2 seconds). All patients were followed up for a minimum of 1.0 years and a maximum of 6.7 years (mean, 3.7Ϯ2.2). One patient (5%) in the pacemaker arm experienced recurrence of syncope compared with 14 patients (61%) in the no-pacemaker arm (Pϭ0.0006). In the no-pacemaker arm, the median time to first syncopal recurrence was 5 months, with a rate of 0.44 per year. On repeated tilt testing performed within 15 days after enrollment, positive responses were observed in 59% of patients with pacemakers and in 61% of patients without pacemakers (PϭNS). Conclusions-In a limited, select group of patients with tilt-positive cardioinhibitory syncope, DDI pacing with hysteresis reduced the likelihood of syncope. The benefit of the therapy was maintained over the long term. Even in untreated patients, the syncopal recurrence burden was low. A negative result of tilt testing was not a useful means to evaluate therapy efficacy. (Circulation. 2000;102:294-299.)

2013 ESC Guidelines on Cardiac Pacing and Cardiac Resynchronization Therapy

“…En todos los estudios de estimulación cardiaca en pacientes vasovagales positivos a la basculación, se usó la estimulación cardiaca bicameral (con una función de respuesta en frecuencia que, ante una disminución rápida del ritmo cardiaco, el marcapasos instauraba estimulación cardiaca DDD rápida), pero no se comparó con la estimulación cardiaca bicameral convencional [20][21][22][23][24] .…”

“…La eficacia de la estimulación cardiaca se estudió en cinco ensayos clínicos multicéntricos aleatorizados [20][21][22][23][24] ; tres estudios sin enmascaramiento dieron resultados positivos y dos estudios con enmascaramiento dieron resultados negativos [21][22][23][24] . En los estudios aleatorizados y abiertos SYDIT y VASIS-PM 20,24 , se seleccionó a los pacientes por la respuesta cardioinhibitoria positiva (sobre todo asistólica) durante la prueba de basculación.…”

“…En los estudios aleatorizados y abiertos SYDIT y VASIS-PM 20,24 , se seleccionó a los pacientes por la respuesta cardioinhibitoria positiva (sobre todo asistólica) durante la prueba de basculación. La recurrencia del síncope a los 2 años en el grupo con marcapasos fue del 7% en SYDIT y el 6% en VASIS-PM.…”

Evaluation and Management of Syncope

“…Two trials showed that patients with tilt-positive cardioinhibitory syncope benefited from pacing. 34,35 However, the control groups did not get a device and placebo effect could not be excluded. In a subsequent trial, patients with pacemakers were randomized to the device being "on" or "off", and pacing therapy did not reduce NCS incidence.…”

Non‐Pharmacological Management of Neurocardiogenic Syncope

“…In the late 1990s, reports were published of a decrease in rates of neurally mediated episodes of syncope by overdrive dual chamber pacing at 100 to 110 bpm, compared to non-paced patients with standard therapy. [27][28][29] However, in more recent trials, this was shown to be attributable to a placebo effect of pacemaker implants. 30,31) Thus, as in the case of drug therapy, the effectiveness of pacing for neurocardiogenic syncope has not been confirmed.…”