Cereb infrc d/t unsp occls or stenos of left mid cereb art

This diagnosis code signifies an ischemic stroke resulting from a blockage or narrowing within the left middle cerebral artery, where the specific nature of the occlusion (e.g., thrombosis, embolism) is not documented. It indicates brain tissue death due to insufficient blood supply to the area typically perfused by the left middle cerebral artery.

Use this code when documentation clearly states a cerebral infarction affecting the left middle cerebral artery, and the physician's notes do not specify the exact cause of the occlusion or stenosis. This code is appropriate when the laterality (left) is known, but the etiology of the blockage remains undetermined.

• Ensure documentation specifies "left" middle cerebral artery; otherwise, an unspecified laterality code may be more appropriate.
• Do not use if the cause of occlusion (e.g., embolism, thrombosis) is clearly documented; instead, select a more specific I63.4- or I63.3- code.
• Always sequence this code after any applicable codes for underlying conditions that may have contributed to the stroke, such as atrial fibrillation or atherosclerosis.