Clinical Research Directory

Inclusion Criteria: 1. ≥18 years scheduled for first-time planned cardiac surgery ( CABG and Valve replacement) 2. Patients who are in sinus rhythm and not taking any antiarrhythmic medication, other than beta-adrenergic blocking agents, at the time of surgery. 3. Willingness to participate and provision of informed consent Exclusion Criteria: 1. Prior history of cardiac surgery. 2. Pediatric population less than 18 years. 3. Patients with history of hyperthyroidism 4. Patients with electrolyte disturbance 5. Where follow-up is not possible. 6. The patient refused to sign the informed consent to participate in the research.