Reversible Sinoatrial Block in a Patient on Bradycardic Calcium Channel Blockers in the Context of Hyperkalemia and Acute Renal Failure

Introduction: Sinoatrial block (SAB) is a rare cardiac conduction abnormality that can occur in the context of electrolyte disturbances, acute renal failure (ARF), and medication side effects. Case presentation: This report describes the case of a patient on verapamil with hyperkalemia due to acute renal failure (ARF), who developed a reversible sinoatrial block (SAB) after correction of the abnormalities and discontinuation of the medication. Discussion: Hyperkalemia played a key role in exacerbating the bradycardia induced by verapamil, while acute renal failure contributed to the accumulation of the drug. Prompt management, including measures to lower potassium levels and adjust antihypertensive therapy, enabled complete recovery without the need for cardiac pacing. Conclusion: This case highlights the importance of closely monitoring electrolytes and treatments in patients with renal failure or similar risk factors.