[Pacemaker ECG quiz no. 24. Implanted the wrong device?].

In a 73-year-old patient, a loop recorder was implanted for syncope of unknown origin which allowed the diagnosis of sinus node disease with sinus bradycardia and sinus arrest. At implantation of a dual-chamber pacemaker, the loop recorder was not explanted. During a pacemaker check-up visit a few months later, the patient complained about slight dizziness together with palpitations. While the interrogation of pacemaker memory did not provide any significant information, the loop recorder had stored several arrhythmias. This case demonstrates that it may be useful not to explant a loop recorder at the time of pacemaker implantation.