Malignant hypertension is charaterized by severe hypertension (i.e.,systolic pressure more than 200mm Hg, diastolic pressure more than 120mm Hg)

Hypertensive crisis. Risk for acute LVD and AMI. Most serious probably being an acute aortic dissection simply due to inability of aorta to contain the pressure and start to tear. Mostly nitroprusside or nicardipine or hydralazine would be used for this to decrease systolic pressure and reduce the aortic shear force.

Hypertension which causes end organ damages is malignant hypertension.