Sick Sinus Syndrome Combined with Wallenberg Syndrome: a Case Report.

Cardiac arrhythmia is a rare manifestation of the Wallenberg syndrome; lesions are located in the brainstem, especially the lower medulla, which regulates sympathetic and parasympathetic activity. A 55-year-old man was admitted to the university hospital with symptoms including ataxia, left ptosis, decreased sensation of pain and temperature on the right side, left facial numbness, and dizziness. Brain magnetic resonance imaging revealed an infarction in the left dorsolateral medulla. Therefore, he was diagnosed with Wallenberg syndrome. While he underwent conservative treatment for Wallenberg syndrome, he experienced several events of self-limiting heart pounding, which required an evaluation of cardiac function. The 24-hour Holter monitor showed an increased RR interval with bradycardia and prolonged sinus pause. As a result, the diagnosis of sick sinus syndrome combined with Wallenberg syndrome was made. Sick sinus syndrome is a rare cardiac complication of the Wallenberg syndrome, and clinicians could overlook it when the initial electrocardiography shows a normal sinus rhythm. Sick sinus syndrome can cause sudden death without appropriate medical intervention. Therefore, clinicians should consider further evaluation, including a 24-hour Holter monitor, to check for the potential presence of sick sinus syndrome in the acute phase of Wallenberg syndrome.