[Neurocardiogenic syncopes in patients with implanted pacemakers]

Recently the tilting table test (tilting up to 70 degrees angle) has established itself for the diagnosis of neurocardiogenic syncope (NS). Usually patients with bradycardic arrhythmias or asystole are treated by pacemaker implantation. But if the syncope is of neurocardiogenic aetiology other therapeutic alternatives must be chosen. We here report on seven patients in whom a pacemaker had been implanted in the treatment of syncopes, in ignorance of their neurocardiogenic aetiology, yet they had recurred.

Pacemakers had been implanted in eight patients: two with sick sinus syndrome, three with sinus bradycardia, one with brady-tachyarrhythmia, one with asystole and one with Mobitz-type 2 degrees AV block. All patients continued to have syncopes, when sitting or standing, months to years after the pacemaker implantation. The tilting table test (up to 30 min at an angle of 70 degrees) was positive in all patients. There was no case of pacemaker malfunction.

One patient declined further treatment. The remaining seven patients were symptom-free in the tilting table test on various medications: theophylline up to 2 x 350 mg, metoprolol up to 2 x 100 mg or disopyramide 3 x 100 mg.

Patients with syncope while sitting or standing should undergo the tilting table test to determine whether the cause is neurocardiogenic so that pacemaker implantation can be avoided. The majority of patients with NS can be successfully treated by drugs. But in some patients pacemaker implantation may have to considered if drug treatment has failed.