Cardiac arrhythmias due to severe hypokalemia in a patient with classic Bartter disease

Abstract

We report a young girl with classic Bartter disease (type III) with severe hypokalemia (< or = 2.0 mmol/l) who developed a prolonged heart rate-corrected QT interval of 510 ms (upper reference 430 ms) and ST segment depression in all leads. Holter electrocardiography was performed (with a plasma potassium level of 2.0 mmol/l) and it disclosed a stable sinus rhythm, a prolonged correct QT interval, more-evident ST segment depression during an increase in heart rate, a few single premature ventricular complexes, and nocturnal conduction abnormalities such as second-degree atrioventricular block 2:1. In the light of these results, the treatment was modified by increasing indomethacin from 1.5 to 3 mg/kg per day and adding spironolactone at a dose of 5 mg/kg per day. After 10 days, plasma potassium levels increased to 2.7 mmol/l and electrocardiographic abnormalities regressed. No other cardiac abnormalities were noted when the serum potassium was maintained > 2.5 mmol/l. In conclusion, this case report supports the link between arrhythmic events and chronic renal hypokalemic alkalosis in renal tubular disorders. We highlight the importance of standardizing the use of rest electrocardiography and 24-h Holter monitoring to diagnose arrhythmic events in children with severe hypokalemic renal disorders, especially in those with a plasma potassium < 2.5 mmol/l. The importance of beginning early medical treatment, to improve plasma potassium levels and reverse cardiac abnormalities, is emphasized.

Cardiac arrhythmias and rhabdomyolysis in Bartter–Gitelman patients

“…Six recent case reports support the assumption that hypokalemia may cause dangerous cardiac arrhythmias in Bartter-Gitelman patients [17][18][19][20][21].…”

Prenatal Diagnosis of Bartter Syndrome with Biochemical Examination of Amniotic Fluid: Case Report

“…There are reports about the importance of standardizing the use of monitoring to diagnose arrhythmic events in children with severe hypokalemic renal disorders, especially in those with a plasma potassium ! 2.5 mmol/l [9] . In a case of antenatal Bartter syndrome fetal heart rate should be monitored and maternal electrolyte levels should maintained in normal levels to prevent this phenomenon.…”

Hipokalemia, hipovolemia y repercusión electrocardiográfica secundarias a ingesta prolongada de furosemida: Caso clínico

“…Probablemente el potencial de reposo transmembrana se afecte más en hipopotasemias intensas y agudas, que en depleciones prolongadas del contenido intracelular y extracelular del catión. Se ha descrito depresión del segmento ST en test de Holter con hipokalemia menor a 2 mEq/l secundaria a Síndrome de Bartter 10 . Sin embargo, un estudio realizado en 21 pacientes portadores de hipokalemia crónica (K + : 2,6 -3,4 mEq/l) por pérdida urinaria secundaria a Síndro-me de Gitelman, no encontró alteraciones en el monitoreo ECG de 24 hrs (Holter) ni cambios del segmento ST en el test de esfuerzo 11 .…”