Risk for QTc prolongation in patients of various medical specialties – a retrospective study on risk factors and usability of the Tisdale Score

BACKGROUND: QTc prolongation is associated with an increased risk of life-threatening arrhythmias. The Tisdale Score was originally developed for risk stratification in cardiac intensive care patients. However, its applicability to other medical specialties remains insufficiently investigated. OBJECTIVE: To evaluate the prevalence of risk factors for QTc prolongation and the performance of the Tisdale Score in patients admitted to surgical-nephrological (CH/N), neurological (NEU), and psychiatric (PSY) general wards. METHODS: In this retrospective study, at least 300 adult inpatients per specialty (admission period July to December 2023) were included. For the day of admission, risk factors for QTc prolongation and administered QTc-prolonging drugs (QTcD) were recorded. Available ECGs were analyzed for QTc prolongation and sensitivity and specificity of the Tisdale Score were calculated. RESULTS: Of 301 CH/N, 306 NEU, and 310 PSY patients, 85.7%, 78.4%, and 87.4% received at least one QTcD, respectively. ECGs were available for 13.6% (CH/N), 17.0% (NEU), and 76.1% (PSY) of patients. QTc prolongation was detected in 3 (7.3%), 5 (9.6%), and 2 (0.9%) patients, respectively. All but one patient with QTc prolongation had a moderate or high Tisdale Score. Sensitivity and specificity were 66.7%/39.5% (CH/N), 100%/53.2% (NEU), and 100%/66.7% (PSY). CONCLUSION: In this retrospective study, most patients with QTc prolongation had a moderate or high Tisdale Score. However, the low number of QTc prolongations and limited ECG availability restrict the precision of performance estimates. Larger studies with more comprehensive ECG monitoring are required to determine the usability of the Tisdale Score for risk stratification in non-cardiac patients.