Diagnostic utility of hybrid single photon emission computed tomography/computed tomography imaging in patients with Takotsubo syndrome

Clinical symptoms and electrocardiographic changes in patients with Takotsubo syndrome can be similar to patients with myocardial infarction. The aim of the study was to assess the impact of SPECT/CT imaging on the diagnosis and management of Takotsubo syndrome (TTS).

Gated single photon emission computed tomography (SPECT)/CT after injection 99Tc-MIBI in resting conditions was performed in 27 patients with TTS using dual-head Symbia T6SPECT/CT hybrid device. CT data were used for attenuation correction of SPECT images and to assess the risk of coronary artery disease on the basis of coronary artery calcium score.

Abnormal myocardial perfusion was found in 20/27 patients. The mean defect size was 9.8 cm, the extent 11.7%, mean total perfusion defect was 10.36%, mean summed rest score (SRS) 6.71.Left ventricle ejection fraction was lower in patients with SRS at least 4 than in patients with SRS less than 4. Perfusion defect size, total perfusion defect, number of akinetic segments in echocardiography and number of segments with perfusion defect in SPECT were higher in the group with SRS at least 4. The applied attenuation correction algorithms did not change the result of our SPECT study.

In the majority of patients with TTS perfusion in SPECT was normal or only minor perfusion defect was observed. Application of CT attenuation correction did not change the final result of myocardial perfusion imaging; therefore, the CT component of the SPECT/CT study performed for attenuation correction is not useful for TTS diagnosis.