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

OBJECTIVE: 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. METHODS: 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). RESULTS: 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. CONCLUSION: CMR might be more accurate than echocardiography for diagnosis of cardiac involvement in AL amyloidosis.