Role of computed tomography and chest radiography in imaging of Impella heart pump and associated complications.

Abstract

Objectives: The objectives of the study are to identify usefulness of chest radiography (CXR) and computed tomography (CT) for the assessment of optimal Impella positioning compared to echocardiography.

Material and methods: In this retrospective study, records of 500 patients were reviewed, 95 subjects met the inclusion criteria. The distance from the carina, top of the aortic arch, and in case of CT, from the aortic valve plane to the Impella inlet port was measured. Subjects were stratified into two groups based on echocardiography: Those that did require repositioning and those that did not.

Results: CT revealed greater distance from the carina to the aortic valve plane in patients requiring Impella repositioning compared to those which did not (81.6 ± 15.9 mm vs. 67 ± 13.2 mm, P = 0.019). The distance from the aortic valve plane to the Impella inlet was shorter in repositioned cases on CT (22.3 ± 28.6 mm vs. 35.8 ± 13.3 mm, P = 0.045). The expected location of the aortic valve plane was 6.8 ± 1.3 cm from the carina among CT cases, representing a useful measurement for evaluation on CXR. Significant predictors of aortic valve plane to carina distance on CT were found to be aortic arch to Impella outlet on CXR (P < 0.0001) and carina to Impella outlet on CXR (P < 0.0001).

Conclusions: CT imaging correctly identified patients that required repositioning on echocardiography. Key CT measurements serve as crucial indicators for repositioning and there is notable agreement on measurements across CXR and CT as well as CT and echocardiography in identification of Impella high or low positioning. In addition, there is evidence of significant predictors of CT measurements from CXR.