ABC | Volume 113, Nº3, September 2019

Review Article Calderado et al. Pulmonary hypertension Arq Bras Cardiol. 2019; 113(3):419-428 Figure 1 – Diagnostic algorithm (adapted fromAlves-Jr, et al. 19 ). DLCO: Diffusing capacity of the lungs for carbon monoxide; V/Q scintigraphy: Ventilation and pulmonary perfusion scintigraphy; CTEPH: PH due to chronic pulmonary thromboembolism; RHC: Right heart catheterization; HRCT: High-resolution CT; TTE: Transthoracic doppler echocardiogram; PVOD: Pulmonary veno-occlusive disease; PCH: pulmonary capillary hemangiomatosis. Symptoms and signs suggestive of PH Echo suggestive of PH? No Yes Consider other causes/re-evaluate Heart or pulmonary disease confirmed Assess the most common PH causes (left heart disease and pulmonary disease): symptoms, signs, risk factors, ECG, chest-XR, chest-CT, lung function test plus CO diffusion capacity Without severe PH symptoms and/or right ventricle dysfunction With severe PH symptoms and/or right ventricle dysfunction CTEPH Treat underlying condition PH Center Perfusion defect and mismatch Low probability of PE Investigate Chronic Pulmonary Embolism Ventilation/Perfusion Scintigraphy Persistence of PH symptoms and/or right ventricle dysfunction Group 5? Sarcoidosis, hemolytic anemia, chronic renal failure... Investigate group 1 related diseases PAOP ≤ 15 PAOP > 15 Treat underlying cardiac disease RIGHT HEART CATH (PH center) mPAP > 20 e PVR ≥ 3 Auto-antibodies and serologic tests Drug-exposure survey High-resolution chest CT Repeat TTE with microbubbles and consider left heart catheterization Doppler-ultrasound of the upper abdomen PAH idiopathic and heritable Connective tissue disease and HIV Drug-induced PH PVOD and PCH Congenital heart disease Periportal fibrosis+ epidemiology Portal hypertension Family history, consider genetic test Schistosomiasis-associated PH Porto-pulmonary hypertension Chest CT Computed angiotomography of the chest plays an important role in the differential diagnosis of PH and its classification, helping to investigate diseases that affect the pulmonary parenchyma and chronic thromboembolism. It can also increase the suspicion of the diagnosis of pulmonary veno‑occlusive disease. Computed tomography findings of increased pulmonary artery diameter, of secondary importance compared to echocardiography, are also suggestive of PH and, thus, can be used in indirect screening. This measurement of the pulmonary artery diameter exhibits quite high specificity for the presence of HP when the diameter is greater than 33.2 mm. 26 Ventilation/Perfusion Scintigraphy Ventilation/perfusion scintigraphy is essential for CTEPH screening due to its high sensitivity (96-97%), combined with a specificity of 90-95%, while chest CT angiography can have a sensitivity of up to 50%. 27 Nevertheless, dual-energy computed tomography has been shown to have the same sensitivity and specificity for CTEPH than scintigraphy. 28 Echocardiography It is the best non-invasive screening method for PH, but it does not establish the definitive diagnosis, nor does it make a clear distinction between the different PH groups (Table 1). 421