[Intermittent focal cerebral ischemia in hypotension due to pacemaker syndrome]

A pacemaker syndrome manifested as transient sensoric aphasia in a 68-year-old woman with a VVI-pace-maker implanted after SA-block. The attack occurred during long-term blood pressure recording and Holter monitoring. Borderline hypotension was documented during ventricular pacing which induced a retrograde excitation of the atrium. Clinical investigations excluded any intracranial abnormality, any source of embolism or stenosis of extra- and intracranial cerebral arteries. Cerebral blood flow measurements revealed a significant increase during pacing at elevated heart rate. Therefore, a device for AV-sequential pacing was implanted and basic pacing rate was elevated. The present case report indicates that focal and not only global cerebral ischemia can be produced by an impairment of systemic hemodynamics due to hypotension and a pacemaker syndrome. Improvement of cerebral blood flow during pacing is an unexpected finding contrasting with the concept of autoregulation. In addition, pacemaker implantation should be discussed in patients with transient cerebral perfusion deficits if an improvement of cerebral blood flow is documented along with rising heart rate.