Stratifying the Utility of Transthoracic Echocardiography for Ischemic Stroke Using a Risk Score

Inpatient transthoracic echocardiography (TTE) is considered to be an important part of secondary prevention in acute ischemic stroke, but can be a barrier to discharge. The goal of the study was to generate a risk score to assess which patients will benefit from a TTE in the inpatient setting.

The training data set consisted of all 874 patients from the UW Health Comprehensive Stroke Registry admitted for acute ischemic stroke/transient ischemic attack (TIA) from 2017 to 2018 that received a TTE. A validation data set of 200 stroke patients was used from the Indiana University Stroke Registry. Using the training data, a modified logistic regression model was developed with simplified coefficients and a limited number of variables. The area under the receiver operator characteristic curve (AUC) was compared between different models and between the training and validation data sets.

The training data consisted of 874 patients (52.97% male; median age 64 years). Validation data set consisted of 200 patients (53.5% male; median age, 64 years). For the final model, termed AL₂OHA, mean AUC on the training data across five-fold cross validation was 0.78 (95% CI, 0.76-0.80). The model consisted of six variables, and one point was awarded for each: atrial fibrillation, large artery atherosclerosis, large vessel occlusion, obesity, prior antihypertensive medication use, and if the patient's age was 18-39 or ≥70. Risk of positive findings was 6.2% for score of 0, 23.1% for score of 1, 57.4% for score of 2, 85.8% for score of 3, 96.4% for score of 4, and 99.2% for score of 5 or greater. When tested on the external validation data set, AUC was 0.73 and demonstrated to not be significantly different than the AUC for the training data set.

The AL₂OHA model is a clinical tool which can stratify which patients admitted for acute ischemic stroke/TIA are more likely to benefit from inpatient TTEs.