Consider the following medical report that includes the patient's historical health records. Use it to predict the disease that the patient is high likely exposed to. 

 Medical Report: history of present illness: the patient is a 60 year-old male with known aortic stenosis who had an echocardiogram demonstrating normal left ventricular chamber wall thickness iwth abnormal relaxation, preserved systolic function with a bicuspid valve with severe stenosis, mean gradient 42, and aortic valve area to .8 to .9. the patient presents for elective aortic valve replacement. past medical history: aortic stenosis with left eye amaurosis fugax. allergies: no known drug allergies. hospital course: on the patient was electively taken to the operating room where he underwent aortic valve replacement with a #23 ce tissue valve. the patient tolerated the procedure well and this was without complications. postoperatively, he was transferred to the cardiac recovery unit where he was maintained briefly on pressors, woke up and extubated without incident. he was transferred to the floor where he continued to do well. chest tubes, pacing wires and foley catheter removed and began tolerating a regular diet, ambulating with physical therapy without complications and will be discharged home. condition on discharge: stable. discharge status: to home. discharge medications: percocet 5/325 one to two po q 4 to 6 hours prn for pain. lasix 40 mg po b.i.d. acetic folic acid 325 mg po q.d., xanax 1 to 2 mg po b.i.d., colace 100 mg b.i.d. and potassium chloride 20 milliequivalents po b.i.d. follow up: the patient will follow up with his primary care physician . and with dr. cardiothoracic surgery in two to four weeks. , m.d. dictated by: medquist36 procedure: extracorporeal circulation auxiliary to open heart surgery reopening of recent thoracotomy site open and other replacement of aortic valve with tissue graft diagnoses: aortic valve disorders hemorrhage complicating a procedure 

Answer: The patient is high likely exposed to