Comparing Echocardiographic Strain Imaging in Cardiac Amyloid and End-Stage Renal Disease Patients

Purpose

Diagnosing cardiac amyloidosis (CA) is difficult due to nonspecific clinical symptoms and echocardiographic findings. Prior studies have suggested that apical sparing strain patterns may be diagnostically useful. With increasing strain usage, it remains unclear how specific this pattern is to diagnose CA. We analyzed strain patterns between CA and end-stage renal disease (ESRD) patient populations.

Methods

Patients with ESRD proven negative for CA (n = 19) were compared to CA patients with CKD stage 3 or less (n = 25). The ESRD cohort was stratified based on time on dialysis. Echocardiographic longitudinal strain (LS) parameters were collected, including regional and global LS, echocardiographic, and demographic parameters. Relative apical LS was calculated using the following equation: average apical LS/(average mid LS + average basal LS).

Results

No significant differences were found regarding regional strain or relative apical strain. Our study showed a sensitivity of 80% and specificity of 42% when using a relative apical strain ratio of >1. All groups demonstrated an apical sparing strain pattern visually on the bulls-eye plot.

Conclusion

ESRD demonstrates significant overlapping findings across various imaging modalities compared to CA. We demonstrated that relative apical sparing strain is nonspecific for CA among patients with ESRD. Our study calls into question the clinical value of relative apical-sparing stain patterns in identifying CA in an ESRD population and suggests that diagnostic evaluation should be driven by strong clinical suspicion and other imaging and demographic variables.