Arrhythmias early in the recovery period after cardio thoracic surgery are common they develop in 11 to 40 percent of patients after coronary-artery bypass grafting. The right chose of sedative agent could decrease the level of arrhythmia incidence.

Arrhythmias are really common in patients after cardiac surgery. Most of the patients get sedation after cardiac surgery. The goal is to determine if the propofol (PR) (sedative agent), dexmedetomidine (DEX)(selective α2-adrenergic receptor (α2-AR) agonist) or their combination could improve and decrease the incidence of the arrhythmia in patients after cardiac surgery.

Inclusion Criteria:

• Multi vascular lesions of the coronary arteries according to coronary angiography;
• Heart valve damage was confirmed by heart ultrasound, which is subject to surgical correction (aortic stenosis of III degree with a gradient on the aortic valve of more than 42 mmHg, aortic insufficiency III, mitral valve stenosis II-III, mitral regurgitation II-III)
• Age of patients from 18-80 years;

Exclusion Criteria:

• Refusal to participate;
• Hypersensitivity to propofol, dexmedetomidine;
• Acute renal failure that occurred during surgery (ClCr less than 50 ml / h, or a decrease in the rate of diuresis to 0.1 ml / h in the first 4 hours after surgery and does not respond to diuretic therapy)