2018 ICD-10-CM coding updates expand your options for specificity. For 2018, ICD-10-CM Chapter 9: Diseases of the Circulatory System (I00-I99) includes expanded code choices for pulmonary hypertension. Let’s review what you need to know to report these conditions appropriately. Understand Hypertension Hypertension (high blood pressure) is when the force of the blood against the artery ...