My father diagnosed with seizure and hypodense lesion....

My father (68yrs) was previously diagnosed with seizure while he was in ARMY.
Now recently CT scan shows the presence of a hypodense lesion (triangular) in basal ganglia region in territory of Lt MCA with CT value 10HU s/o infarct.
Other reports shows
Glucose fasting 90 mg/dl, bilirubin 1.0 mg/dl, urea 45 mg/dl, creatinine 1.3 mg/dl, cholesterol 228 mg/dl, triglycerides 296 mg/dl, HDL 60, LDL 109, VLDL 59 mg/dl, alkaline phosphatase 63, SGOT 41 IU, SGPT 20 IU.
Dr. says that he has high blood pressure. How much serious is the problem and what would we do now?