CPT code 93798 represents supervised exercise sessions with continuous electrocardiographic (ECG) monitoring and concurrent dietary review by the provider. This code captures services delivered in cardiac rehabilitation or outpatient exercise programs where clinical supervision and ECG monitoring are integral to patient safety and care. Nationally, coding for supervised cardiac exercise is important for tracking cardiac rehabilitation utilization and supporting quality measures tied to secondary prevention after cardiac events. Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of what the code covers, typical sites of service, common modifiers, and payer coverage context. The publication outlines benchmarking elements and clinical context relevant to exercise-based cardiac rehabilitation, plus notes on billing practice patterns where available. Data not available in the input is noted where applicable. The intent is to give clinicians, billing staff, and policy analysts a clear, national-level summary of CPT code 93798, its clinical setting, and the payer landscape for reimbursement and administrative planning.