Eur Respir Rev. 2017 Mar 15;26(143).

Gopalan D, Delcroix M, Held M.

Chronic thromboembolic pulmonary hypertension (CTEPH) is the only potentially
curable form of pulmonary hypertension. Rapid and accurate diagnosis is pivotal
for successful treatment. Clinical signs and symptoms can be nonspecific and risk
factors such as history of venous thromboembolism may not always be present.
Echocardiography is the recommended first diagnostic step. Cardiopulmonary
exercise testing is a complementary tool that can help to identify patients with
milder abnormalities and chronic thromboembolic disease, triggering the need for
further investigation. Ventilation/perfusion (V’/Q’) scintigraphy is the imaging
methodology of choice to exclude CTEPH. Single photon emission computed
tomography V’/Q’ is gaining popularity over planar imaging. Assessment of
pulmonary haemodynamics by right heart catheterisation is mandatory, although
there is increasing interest in noninvasive haemodynamic evaluation. Despite the
status of digital subtraction angiography as the gold standard, techniques such
as computed tomography (CT) and magnetic resonance imaging are increasingly used
for characterising the pulmonary vasculature and assessment of operability.
Promising new tools include dual-energy CT, combination of rotational angiography
and cone beam CT, and positron emission tomography. These innovative procedures
not only minimise misdiagnosis, but also provide additional vascular information
relevant to treatment planning. Further research is needed to determine how these
modalities will fit into the diagnostic algorithm for CTEPH.