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Updated: May 27, 2026
Transthoracic Speckle Tracking Echocardiography for the Quantitative Assessment of Left Ventricular Myocardial Deformation
Published on: October 20, 2016
Role of the vectorcardiogram-derived spatial QRS-T angle in diagnosing left ventricular hypertrophy
Sumche Man1, Chinar Rahmattulla, Arie C Maan
1Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
Insights
Diagnosing left ventricular hypertrophy (LVH) using electrocardiograms (ECG) is improved by combining body surface area (BSA) and spatial QRS-T angle (SA). This new method offers higher accuracy than traditional ECG criteria for detecting LVH.
Area of Science:
- Cardiology
- Medical Diagnostics
- Biomedical Engineering
Background:
- Conventional electrocardiogram (ECG) criteria for diagnosing left ventricular hypertrophy (LVH) exhibit limited accuracy.
- Hypertrophy-related changes in action potential and conduction may manifest as altered QRS and T-wave morphology.
- Vectorcardiographic variables, such as spatial QRS-T angle (SA), may offer additional diagnostic information.
Purpose of the Study:
- To enhance the diagnostic accuracy of left ventricular hypertrophy (LVH).
- To evaluate the combined utility of demographic, anthropomorphic, ECG, and vectorcardiographic variables for LVH detection.
- To develop a diagnostic model incorporating these variables.
Main Methods:
- A study group of 196 participants was categorized based on echocardiographic and ECG findings for LVH.
- Data were split into two sets (A and B) for model development and testing.
- A stepwise linear discriminant model was built using variables including body surface area (BSA) and spatial QRS-T angle (SA).
Main Results:
- A discriminant model equation was derived: D = 5.130 × BSA - 0.014 × SA - 8.74.
- The model achieved a diagnostic accuracy of 79% for LVH.
- This accuracy significantly surpasses the 57% accuracy of conventional ECG criteria.
Conclusions:
- Combining body surface area (BSA) and spatial QRS-T angle (SA) significantly improves LVH diagnostic accuracy.
- This integrated approach offers a more reliable method for identifying left ventricular hypertrophy compared to standard ECG methods.
Introduction:
Current criteria for electrocardiographic (ECG) diagnosis of left ventricular hypertrophy (LVH) have a low diagnostic accuracy. Addition of demographic, anthropomorphic, and additional ECG variables may improve accuracy. As hypertrophy affects action potential morphology and intraventricular conduction, QRS prolongation and T-wave morphology may occur and become manifest in the vectorcardiographic variables spatial QRS-T angle (SA) and spatial ventricular gradient. In this study, we attempted to improve the diagnostic accuracy for LVH by using a combination of demographic, anthropomorphic, ECG, and vectorcardiographic variables.
Methods:
The study group (n = 196) was divided in 4 subgroups with, on one hand, echocardiographically diagnosed LVH or a normal echocardiogram and, on the other hand, with any of the conventional ECG signs for LVH or with normal ECGs. Each subgroup was randomly split into halves, yielding 2 equally-sized (n = 98) data sets A and B. Age, sex, height, weight, body mass index, body surface area (BSA), frontal QRS axis, QRS duration, QT duration, maximal QRS vector magnitude, SA, and ventricular gradient magnitude and orientation were univariate studied by receiver operating characteristic analysis and were used to build a stepwise linear discriminant model using P < .05 as entry and P > .10 as removal criterion. The discriminant model was built in set A (model A) and tested on set B. Stability checks were done by building a discriminant model on set B and testing on set A and by cross-validation analysis in the complete study group.
Results:
The discriminant model equation was D = 5.130 × BSA - 0.014 × SA - 8.74, wherein D greater than or equal to 0 predicts a normal echocardiogram and D less than 0 predicts LVH. The diagnostic accuracy (79%) was better than the diagnostic accuracy of conventional ECG criteria for LVH (57%).
Conclusion:
The combination of BSA and SA yields a diagnostic accuracy of LVH that is superior to that of the conventional ECG criteria.
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