In simple words: This code means the doctor has diagnosed pulmonary hypertension (high blood pressure in the arteries of the lungs), but the exact reason for it is unknown after conducting tests.

I27.20, Pulmonary hypertension, unspecified, is an ICD-10-CM code used to classify cases of pulmonary hypertension where the underlying cause cannot be definitively determined.This code falls under the broader category of "Other secondary pulmonary hypertension" (I27.2).Appropriate documentation should detail the clinical findings supporting the diagnosis of pulmonary hypertension, including hemodynamic measurements and any relevant investigations performed to identify a potential cause which were ultimately inconclusive.The selection of this code implies that the physician has explored potential etiologies without reaching a specific diagnosis.

Example 1: A 60-year-old female presents with shortness of breath and fatigue.Echocardiography reveals elevated pulmonary artery pressure, but further investigations, including CT pulmonary angiography and cardiac catheterization, fail to identify a specific cause.I27.20 is assigned., A 45-year-old male with a history of systemic hypertension and chronic obstructive pulmonary disease experiences worsening dyspnea.Right heart catheterization confirms pulmonary hypertension; however, no specific underlying condition is identified to explain it. I27.20 is assigned., A 72-year-old female admitted for worsening heart failure demonstrates elevated pulmonary artery pressures on echocardiography.Investigations are performed, but they do not reveal a definable cause of her pulmonary hypertension. I27.20 is appropriate.

Detailed patient history including symptoms (e.g., dyspnea, fatigue, chest pain), risk factors (e.g., family history, connective tissue disorders), and relevant past medical history.Comprehensive physical examination findings. Results of diagnostic testing including echocardiography (showing elevated pulmonary artery pressure and right ventricular dysfunction), cardiac catheterization (right heart pressures and oxygen saturations), and imaging studies (e.g., CT pulmonary angiography, chest X-ray) to rule out other causes.Documentation of the physician's clinical judgment as to the inconclusive nature of investigations in assigning this unspecified code.

** This code should be used cautiously and only when a thorough workup has failed to identify a specific underlying cause of the pulmonary hypertension.The documentation must clearly reflect the investigation undertaken and the clinical rationale for using this unspecified code.