Diagnostic compatibility of V/Q SPECT and CTPA, which are non-invasive diagnostic methods, for the detection of CTEPH, which is a treatable cause of pulmonary hypertension.

Objective: To evaluate the compatibility between ventilation/perfusion (V/Q) single photon emission computed tomography (SPECT) scintigraphy and computed tomography pulmonary angiography (CTPA) in diagnosing chronic thromboembolic pulmonary hypertension (CTEPH).

Subject and methods: Twenty cases of CTEPH, out of 98 patients with pre-diagnosis of pulmonary hypertension (PH), who was diagnosed with CTEPH with a multidisciplinary approach and a council decision, were included in the study retrospectively. The diagnostic performances of V/Q SPECT and CTPA, which are used as noninvasive methods in diagnosing CTEPH, and the compatibility between them were calculated statistically.

Results: Of 20 patients diagnosed with CTEPH, 12 were female, and 8 were male; the mean age was 59.1 (range: 36-79). The sensitivity of V/Q SPECT scintigraphy of imaging methods used to diagnose CTEPH was 90%, CTPA was 80%, specificities were 88% and 92%, respectively, and accuracy was 88% in both cases methods. According to the reference standard, the kappa value for V/Q scintigraphy was calculated as 0.765 and 0.678 for CTPA. These values were statistically significant (P<0.01), and there was a substantial concordance between them.

Conclusion: There is significant compatibility between V/Q SPECT scintigraphy and CTPA in diagnosing CTEPH, whose differential diagnosis is essential because of its high cure potential due to PH causes.