Case Report: Syncopal atrioventricular block complicating primary hyperoxaluria type 1

Primary hyperoxaluria (PH) type 1 is a rare hereditary metabolic disorder resulting in accumulation of calcium oxalate in several organs, including the heart. Cardiac oxalosis in PH is poorly described in the medical literature. We report the case of a 42-year-old woman diagnosed with primary hyperoxaluria type 1 and end-stage renal failure who presented with syncope related to a paroxysmal third-degree atrioventricular block. The patient benefited from the implantation of a dual chamber pacemaker with a good outcome. Conduction blocks in case of primary hyperoxaluria type 1 are exceptional; in fact, less than five reports have previously been published in the medical literature. With this case, we would like to highlight the need for regular and careful monitoring of cardiac status in patients treated for primary oxalosis, especially when renal function is impaired.