title: [Sinus node dysfunction with intermittent sinus arrest and AV-nodal escape rhythm as initial manifestation of pheochromocytoma].
abstract: A 25-year-old male student complained about episodic palpitations, dizziness, nausea and headache 5 years prior to presentation. No otorhinolaryngic, neurologic or gastrointestinal causes were identified. Several ECG recordings revealed sinus node dysfunction with intermittent sinus arrest and AV-nodal escape rhythm. The patient was given a permanent DDD-pacemaker. Six months later, the clinical symptoms were unchanged. During an attack, physical examination revealed paleness, diffuse sweating and an arterial blood pressure of 250/130 mmHg, which decreased to 120/80 mmHg within a few minutes. Abdominal ultrasound and abdominal computed tomographic scan demonstrated the presence of a large (6.4 x 5.5 cm) left-sided adrenal mass. Two 24-h-urinary collections demonstrated elevated noradrenaline (mean 315 micrograms/24 h, normal < 80 micrograms/24 h) and adrenaline (mean 268 micrograms/24 h, normal < 20 mg/24 h) levels. Blood samples, which were drawn during excessive blood pressure rise, revealed elevation of plasma catecholamines (6.793 pg/ml for adrenaline (normal 50-150 pg/ml) and 10.424 pg/ml for noradrenaline (normal 200-500 pg/ml), so that the diagnosis of pheochromocytoma was considered established. The tumor was successfully removed during laparascopic surgery. After surgery, the patient remained well and normotensive. Three months later, several long-term ECG recordings showed sinus arrhythmia with no evidence of sinus arrest or AV-nodal escape rhythm, so that the DDD pacemaker was turned off. This case underlines that sinus node dysfunction with intermittent sinus arrest and AV-nodal escape rhythm is a potential early manifestation of a pheochromocytoma. These changes seem to disappear after successful removal of the tumor.
authors.affiliation: Westfälische Wilhelms-Universität Münster Innere Medizin C Albert-Schweitzer-Str. 33 48129 Münster, Germany. bruchc@uni-muenster.de
authors.forename: C
authors.initials: C
authors.lastname: Bruch
authors.forename: N
authors.initials: N
authors.lastname: Dagres
authors.forename: H
authors.initials: H
authors.lastname: Wieneke
authors.forename: C
authors.initials: C
authors.lastname: Herborn
authors.forename: K
authors.initials: K
authors.lastname: Brandt-Mainz
authors.forename: R
authors.initials: R
authors.lastname: Erbel
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D000328:Adult; D001146:Arrhythmia, Sinus / Q000209:etiology / Q000628:therapy; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000628:therapy; D004562:Electrocardiography; D005500:Follow-Up Studies; D006801:Humans; D010535:Laparoscopy; D008297:Male; D010138:Pacemaker, Artificial; D010673:Pheochromocytoma / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014463:Ultrasonography