Low voltage criteria EKG as a harbinger of systemic disease

Abstract

AL amyloidosis is due to deposition of protein derived from immunoglobulin light chain fragments. It is a systemic disorder in which deposition of plasma proteins can adversely affect function of the heart, liver, kidneys, and peripheral nerves. Deposition in the heart results in a decrease in the amplitude of the electrical activity of the heart and can be an early clue to the diagnosis.

A 63-year-old male admitted for volume overload was found to have nephrotic range proteinuria, progressive renal insufficiency (Creatinine 4.0 increased from his baseline 0.9), and hypoalbuminemia. On exam, he had diffuse anasarca and peripheral neuropathy. A renal biopsy showed AL amyloidosis, lambda related, involving the glomeruli, interstitium, and arterial walls. Bone marrow biopsy showed 30% plasma cells with lambda light chain predominance. Serum free light chains were elevated. Lamda was 11.50 mg/dL and kappa was 5.12 mg/dL. In retrospective review of his chart, an EKG with low voltage and anterior pseudo-infarct pattern was first apparent on an admission for stroke two years prior. Echocardiogram showed mild concentric left ventricular hypertrophy. The patient was started on chemotherapy with Bortezomib.

The differential of a low-voltage EKG includes many common pulmonary and chest wall (COPD, obesity) as well as pericardial diseases (effusions), but also important rarer infiltrative diseases including sarcoidosis and amyloidosis. Amyloidosis of the heart can cause progressive irreversible heart failure, but its progress can be altered if identified early. Physicians should consider amyloidosis when faced with a low-voltage EKG along with systemic symptoms including nephrotic range proteinuria, peripheral neuropathy, hepatosplenomegaly, and macroglossia.