Primo-implantation of a dual-chamber pacemaker in a patient with symptomatic first-degree AV block with proven AV dyssynchrony at an abnormally long PQ interval (pseudopacemaker syndrome)

First-degree atrioventricular block (first-degree AV block) is defined as a PR interval exceeding 200 ms [1]. The abnormally long PR interval may result in the condition resembling pacemaker syndrome, i.e. the collision of the atrial systole and the ventricular systole, being accompanied with similar symptoms including cardiac failure even if the systolic function of the left ventricle [2] is normal. This is called “pseudopacemaker syndrome” [3], [4], [5], [6], [7], [8], [9], [10]. This paper describes the case of a female patient with a significantly long PR interval after the replacement of the mitral valve, showing symptoms of pseudopacemaker syndrome. This is a relatively rare clinical condition. When it occurs, the implantation of a pacemaker in Class IIa [11] is recommended.