Electroanatomic voltage mapping (EVM) is a promising approach to guide endomyocardial biopsies (EMBs).
A total of 162 consecutive patients with EMB from 2010 to 2019 were included in the study. EMB was performed on lesion areas identified by EVM and cardiac magnetic resonance (CMR). Based on the EMB results, the sensitivity and specificity of EVM and CMR to identify the lesion area were evaluated.
70% of patients had delayed gadolinium imaging on preoperative CMR, and 61% of patients had low-voltage areas on EVM. Biopsies were sampled from the right ventricle (73%), left ventricle (19%), and bicompartment (8%). EVM was similar in sensitivity to CMR (74% vs 77%) and specificity was 70% and 47%, respectively. In 12 patients with EMB-confirmed cardiomyopathy, EVM identified the lesion area (CMR did not). The pooled sensitivity of EVM and CMR was as high as 95%. EMB results in 39% of patients yielded a different diagnosis (different from clinical suspicion). Complication rates were low, mostly vascular complications, and no patients required urgent treatment.
Given the sensitivity and specificity, EVM is a promising tool to guide EMB. EVM accuracy is similar to CMR. The combined positive predictive value of EVM and CMR was 89% (compared to EMB).
Baseline characteristics are shown in the table below,
Comparison of pre- and post-EMB diagnosis See the table below,
The EVM and EMB data are shown in the table below,
EVM and CM R Sensitivity and specificity are shown in the table below,
CMR and EVM of different types of cardiomyopathy are shown in the table below,
Example of eosinophilic myocarditis is shown below,
Circulation. 2020;142:1249–1260.