Benefit of Dual-chamber Pacing With Closed Loop Stimulation (CLS) in Tilt-induced Cardioinhibitory Reflex Syncope

Inclusion Criteria: Patients affected by clinical diagnosis of reflex syncope who meet all the following criteria: * age \>=40 years * significant limitation of social and working life due to unpredictable or frequent syncope recurrences, ≥2 within the last year. * type 2B cardio-inhibitory response to TT (according to the VASIS classification). * Alternative therapies have failed or were not feasible. * exclusion of other possible competitive causes of syncope. Exclusion Criteria: \- Any other indication to IPG, implantable defibrillator (ICD), cardiac resynchronization therapy (CRT), according to current guidelines Any cardiac dysfunctions possibly leading to loss of consciousness: * overt heart failure; * ejection fraction (LVEF) \<40% (Echo-assessed within 3-month prior to study participation); * myocardial infarction; * diagnosis of hypertrophic or dilated cardiomyopathy; * clinically significant valvular disease; * sinus bradycardia \<50 bpm or sinoatrial block; * Mobitz I second-degree atrioventricular block; * Mobitz II second or third-degree atrioventricular block; * bundle-branch block; * rapid paroxysmal supraventricular tachycardia or ventricular tachycardia; * preexcited QRS complexes; * prolonged QT interval; * Brugada syndrome; * arrhythmogenic right ventricular cardiomyopathy * Symptomatic orthostatic hypotension diagnosed by standing BP measurement; * Nonsyncopal loss of consciousness (eg, epilepsy, psychiatric, metabolic, drop-attack, cerebral transient ischemic attack, intoxication, cataplexy). * Symptomatic cardioinhibitory carotid sinus hypersensitivity.