Is pulmonary hypertension the same as hypertension?

No. Pulmonary HTN refers to increased pressures in the arteries between the heart and lung downstream from the right ventricle while hypertension refers to systemic arterial high blood pressure (the arteries that are downstream from the left ventricle.
Different. They are different. The pressure generated by the left side of the heart and arteries of the body in general is referred to as hypertension. On the other hand the pressure generated by the right side of the heart and the arteries of the lungs is pulmonary hypertension. Both can be dangerous and need evaluation and treatment.
No. Pulmonary hypertension is basically high blood pressure in the heart and lungs and can be caused by many diseases, and is unrelated to systemic hypertension.
No. Pulmonary hypertension (PH) is abnormally high blood pressure (BP) in the arteries of the lungs whereas hypertension refers to high BP in the systemic circulation measured by a BP cuff on the arm.