Assessing left ventricular systolic function by emergency physician using point of care echocardiography compared to expert: systematic review and meta-analysis

Assessing left ventricular systolic function (LVSF) by echocardiography assists in the diagnosis and management of a diverse range of patients presenting to the emergency department (ED). We evaluated the agreement between ED-based clinician sonographers and apriori-defined expert sonographers. We conducted a systematic review and meta-analysis based on Preferred Reporting Items for Systematic reviews and Meta-Analysis guidelines. We searched Medline, EMBASE, Cochrane, ClinicalTrials.gov, TRIP and Google Scholar for eligible studies from inception to February 2021. Risk of bias was evaluated using Quality Assessment Tool for Diagnostic Accuracy Studies-2 tool. The level of agreement between clinician and expert sonographers was measured using kappa, sensitivity, specificity, positive and negative likelihood ratio statistics using random-effects models. Twelve studies were included (1131 patients, 1229 scans and 159 clinician sonographers). Significant heterogeneity was identified in patient selection, methods of assessment of LVSF, reference standards and statistical methods for assessing agreement. The overall quality of studies was low, with most being small, single centre convenience samples. A meta-analysis including seven studies (786 scans) where visual estimation method was used by clinician sonographers demonstrated simple Kappa of 0.68 [95% confidence interval (CI), 0.57–0.79], and sensitivity, specificity, positive and negative likelihood ratio of 89% (95% CI, 80–94%), 85% (95% CI, 80–89%), 5.98 (95% CI, 4.13–8.68) and 0.13 (95% CI, 0.06–0.24), respectively, between clinician sonographer and expert sonographer for normal/abnormal LVSF. The weighted kappa for five studies (429 scans) was 0.70 (95% CI, 0.61–0.80) for normal/reduced/severely reduced LVSF. There is substantial agreement between ED-based clinician sonographers and expert sonographers for assessing LVSF using visual estimation and ranking it as normal/reduced, or normal/reduced/severely reduced, in patients presenting to ED.