The role of cardiac imaging for diagnosis of cardiac amyloidosis: a systematic review and meta-analysis of test accuracy

To evaluate the diagnostic test accuracy of cardiac magnetic resonance (CMR) and echocardiography for diagnosis of cardiac involvement in patients with biopsy proven light-chain (AL) amyloidosis. This systematic review addresses late gadolinium enhancement (LGE) on CMR and different echocardiographic findings for cardiac involvement using an acceptable reference standard. Meta-analysis reported sensitivity and specificity with 95% confidence intervals when we have ≥3 studies, or ranges for 2 studies. We assessed certainty of evidence using GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Seven studies evaluated LGE, yielding pooled sensitivity and specificity of 0.95 (0.87–0.98) and 0.87 (0.76–0.94). Nineteen studies addressed echocardiography. Interventricular septum thickness showed sensitivity of 0.77 (0.69–0.84) and specificity of 0.71 (0.60–0.81). Diastolic dysfunction (grade 2–3) sensitivity was 0.71 (0.40–0.90) and specificity was 0.75 (0.64–0.84); restrictive filling pattern (grade 3) sensitivity was 0.42 (0.28–0.58) and specificity 0.89 (0.83–0.94). E/A ratio sensitivity ranged from 0.45 to 0.65, with specificity from 0.85 to 0.98. Global longitudinal strain sensitivity was 0.86 (0.65–0.95) and specificity was 0.76 (0.55–0.89). Apical sparing pattern showed sensitivity of 0.72 (0.64–0.78) and specificity of 0.78 (0.64–0.88). Certainty of evidence was very low. CMR might be more accurate than echocardiography for diagnosis of cardiac involvement in AL amyloidosis.