May 06, 2023
Mayo Clinic now offers a practical diagnostic solution that does not require a high level of electrocardiogram (ECG) interpretation expertise. The Mayo Clinic ventricular tachycardia calculator (MC-VTcalc) assists clinicians in successfully differentiating wide QRS complex tachycardias (WCTs) in adults into ventricular tachycardia (VT) or supraventricular wide complex tachycardia (SWCT).
The discrimination of VT versus SWCT via 12-lead ECG is paramount for achieving appropriate, high‐quality, and cost‐effective care in patients presenting with wide QRS complex tachycardia (WCT). Critical patient management decisions rely on accurate and timely WCT differentiation into VT or SWCT. A true VT misclassified as SWCT can lead to adverse, even fatal, patient outcomes. Alternatively, a true SWCT misdiagnosed as VT might result in the initiation of potentially harmful medications, inappropriate invasive interventions and increased health care expenses.
Several decades of clinical research have brought forth an expansive arsenal of ready-to-use manual ECG interpretation methods for differentiating WCTs. A central limitation of manual methods is their heavy reliance on the ECG interpreter for proper execution. Thus, despite the availability of numerous manual ECG interpretation criteria or algorithms, the accurate differentiation of VT and SWCT continues to be outwardly problematic, especially among CG interpreters who are not experts. The application of existing manual WCT differentiation methods is commonly thwarted by improper use or lack of use in real life clinical practice.
Given the well-known challenges of executing manual WCT differentiation methods in clinical practice, Mayo Clinic investigators sought to offer a practical diagnostic solution that would not require a high level of ECG interpretation expertise. These investigators have since created the MC-VTcalc a new generalizable, accurate and easy-to-use tool, to assist clinicians successfully discriminating VT and SWCT.
This tool merely requires the manual entry of computerized measurements, that is, QRS duration, QRS axis and T wave axis, routinely displayed on WCT and baseline ECG recordings, thereby offering a simple means for nonexpert ECG interpreters to successfully differentiate WCTs. Moreover, the MC-VTcalc provides another tool in clinicians' armamentaria that can be independently integrated with other important clinical factors (e.g., history of myocardial infarction) or diagnoses reached by traditional WCT differentiation methods (e.g., Brugada and Vereckei aVR algorithms).
The scientific basis of the MC-VTcalc comes from previously published works detailing the derivation, validation and later subsequent prospective evaluation of the VT Prediction Model. In prior scientific works, Mayo Clinic investigators demonstrated that the overall diagnostic performance of the VT Prediction Model was excellent. And it showed favorable diagnostic performance indexes across various VT probability cut points (or likelihood that the WCT is VT), ranging from 0.000% to 99.999%. Subsequent prospective analysis confirmed that application of the MC-VTcalc favorably improved ECG interpretation accuracy and ECG interpreter confidence for discriminating VT and SWCT.
For more information
Adam MM, et al. The VT Prediction Model: A simplified means to differentiate wide complex tachycardias. Journal of Cardiovascular Electrophysiology. 2020;1:185.
Anthony KH, et al. The ventricular tachycardia prediction model: Derivation and validation data. Data in Brief. 2020.
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