Lower spatial QRS-T angle rules out sustained ventricular arrhythmias in children with hypertrophic cardiomyopathy

Cortez, Daniel; Sharma, Nandita; Cavanaugh, Jean; Tuozo, Froilan; Derk, Gwendolyn; Lundberg, Emily; Weiner, Keith; Kiciman, Nafiz; Alejos, Juan; Landeck, Bruce F.; Aboulhosn, Jamil; Miyamoto, Shelley D.; McCanta, Anthony C.; Batra, Anjan S.

doi:10.1017/s1047951116000640

Cited by 7 publications

(6 citation statements)

References 26 publications

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“…The maximum vector-based QRS-T angle calculation is based on the notion that QRS and T wave orientations are defined by the maxima of the vector magnitudes within the corresponding orthogonal loops ( Cortez et al, 2017a ). That is, within the orthogonal

system of ECG leads, time points

and

are selected such that

and similarly

, where

, and

again specify QRS onset, QRS offset, and T wave offset, respectively.…”

Section: Methodsmentioning

confidence: 99%

“…In 2000, however, the seminal report by Zabel et al, (2000) showed that the angle of the ventricular gradient, that is the 3-dimensional angle between the QRS and T wave orientations, is a potent predictor of mortality risk in survivors of acute myocardial infarction. Subsequently, the risk stratification strength of the QRS-T angle has been confirmed in a large number of studies including investigations of other ischaemic heart disease populations ( de Torbal et al, 2004 ; Malik et al, 2004 ), acute coronary syndrome ( Lown et al, 2012 ), heart failure ( Gotsman et al, 2013 ; Selvaraj et al, 2014 ; Sweda et al, 2020 ), hypertrophic ( Cortez et al, 2017a ; Cortez et al, 2017b ; Jensen et al, 2021 ) and dilated cardiomyopathy ( Li et al, 2016 ), diabetic patients ( Voulgari et al, 2010 ; Cardoso et al, 2013 ; May et al, 2017 ; May et al, 2018 ), renal patients on haemodialysis ( de Bie et al, 2013 ; Poulikakos et al, 2018 ); and many other populations and conditions ranging from systemic sclerosis ( Gialafos et al, 2012 ) and Chagas disease ( Zampa et al, 2014 ) to overall hospital ( Yamazaki et al, 2005 ) and general populations ( Kardys et al, 2003 ; Kors et al, 2003 ; Walsh et al, 2013 ). It has also recently been shown that QRS-T angle might be meaningfully combined with other ECG-based risk factors ( Hnatkova et al, 2022 ).…”

Section: Introductionmentioning

confidence: 91%

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Intra-subject stability of different expressions of spatial QRS-T angle and their relationship to heart rate

et al. 2022

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Three-dimensional angle between the QRS complex and T wave vectors is a known powerful cardiovascular risk predictor. Nevertheless, several physiological properties of the angle are unknown or poorly understood. These include, among others, intra-subject profiles and stability of the angle relationship to heart rate, characteristics of angle/heart-rate hysteresis, and the changes of these characteristics with different modes of QRS-T angle calculation. These characteristics were investigated in long-term 12-lead Holter recordings of 523 healthy volunteers (259 females). Three different algorithmic methods for the angle computation were based on maximal vector magnitude of QRS and T wave loops, areas under the QRS complex and T wave curvatures in orthogonal leads, and weighted integration of all QRS and T wave vectors moving around the respective 3-dimensional loops. These methods were applied to orthogonal leads derived either by a uniform conversion matrix or by singular value decomposition (SVD) of the original 12-lead ECG, giving 6 possible ways of expressing the angle. Heart rate hysteresis was assessed using the exponential decay models. All these methods were used to measure the angle in 659,313 representative waveforms of individual 10-s ECG samples and in 7,350,733 individual beats contained in the same 10-s samples. With all measurement methods, the measured angles fitted second-degree polynomial regressions to the underlying heart rate. Independent of the measurement method, the angles were found significantly narrower in females (p < 0.00001) with the differences to males between 10o and 20o, suggesting that in future risk-assessment studies, different angle dichotomies are needed for both sexes. The integrative method combined with SVD leads showed the highest intra-subject reproducibility (p < 0.00001). No reproducible delay between heart rate changes and QRS-T angle changes was found. This was interpreted as a suggestion that the measurement of QRS-T angle might offer direct assessment of cardiac autonomic responsiveness at the ventricular level.

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system of ECG leads, time points

and

are selected such that

and similarly

, where

, and

again specify QRS onset, QRS offset, and T wave offset, respectively.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 91%

Intra-subject stability of different expressions of spatial QRS-T angle and their relationship to heart rate

et al. 2022

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“…9 Electrocardiogram (ECG)-derived vectorcardiographic (VCG) repolarization parameters offer the possibility of objective T-wave morphology measure and have demonstrated significant diagnostic and prognostic value in patients at risk for sudden cardiac death. [10][11][12][13][14][15][16][17][18][19] ECG-derived VCG has shown prognostic utility in LQTS patients with prolonged QTc values, while in LQTS patients without QTc prolongation, neither spatial durations nor the spatial QRS-T angle was able to differentiate symptomatic from asymptomatic LQTS patients. 20,21 Assessment of the shape of the T-wave can be a way to identify patients with LQT2 without QTc prolongation at risk for cardiac events 4,9 ; however, qualitative methods may be operator-dependent and subject to interindividual variability.…”

Section: Introductionmentioning

confidence: 99%

“…Electrocardiogram (ECG)‐derived vectorcardiographic (VCG) repolarization parameters offer the possibility of objective T‐wave morphology measure and have demonstrated significant diagnostic and prognostic value in patients at risk for sudden cardiac death . ECG‐derived VCG has shown prognostic utility in LQTS patients with prolonged QTc values, while in LQTS patients without QTc prolongation, neither spatial durations nor the spatial QRS‐T angle was able to differentiate symptomatic from asymptomatic LQTS patients …”

Section: Introductionmentioning

confidence: 99%

Quantitative T‐wave morphology assessment from surface ECG is linked with cardiac events risk in genotype‐positive KCNH2 mutation carriers with normal QTc values

Cortez

Zaręba

McNitt

et al. 2019

Cardiovasc electrophysiol

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Introduction Long QT syndrome (LQTS) mutation carriers have elevated the risk of cardiac events even in the absence of QTc prolongation; however, mutation penetrance in patients with normal QTc may be reflected in abnormal T‐wave shape, particularly in KCNH2 mutation carriers. We aimed to assess whether the magnitude of a three‐dimensional T‐wave vector (TwVM) will identify KCNH2‐mutation carriers with normal QTc at risk for cardiac events. Methods Adult LQT2 patients with QTc < 460 ms in men and <470 ms in women (n = 113, age 42 ± 16 years, 43% male) were compared with genotype‐negative family members (n = 1007). The TwVM was calculated using T‐wave amplitudes in leads V6, II, and V2 as the square root of (TV62 + TII2 + (0.5*TV2)2). Cox regression analysis adjusted for gender and time‐dependent beta‐blocker use was performed to assess cardiac event (CE) risk, defined as syncope, aborted cardiac arrest, implantable cardioverter‐defibrillator therapy, or sudden death. Results Dichotomized by median of 0.30 mV, lower TwVM was associated with elevated CE risk compared to those with high TwVM (HR = 2.95, 95% CI, 1.25‐6.98, P = .014) and also remained significant after including sex and time‐dependent beta‐blocker usage in the Cox regression analysis (HR = 2.64, 95% CI, 1.64‐4.24, P < .001). However, these associations were found only in women but not in men who had low event rates. Conclusion T‐wave morphology quantified as repolarization vector magnitude using T‐wave amplitudes retrieved from standard 12‐lead electrocardiogram predicts cardiac events risk in LQT2 women and appears useful for risk stratification of KCNH2‐mutation carriers without QTc prolongation.

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“…In all hypertrophic, dilated and left ventricular non-compaction cardiomyopathies, ventricular arrhythmia may occur and heart failure may progress, resulting in death. The literature on the usefulness of the QRS-T angle in children with hypertrophic and non-compaction cardiomyopathies is limited [ 14 , 15 ]. To our knowledge, the QRS-T angle in children with idiopathic dilated cardiomyopathy (DCM) has not been assessed previously.…”

Section: Introductionmentioning

confidence: 99%

Electrocardiographic Parameters Associated with Adverse Outcomes in Children with Cardiomyopathies

Łuczak-Woźniak

Obsznajczyk²,

Niszczota³

et al. 2022

JCM

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Cardiomyopathies have a low prevalence in children and thus may lead to malignant ventricular arrhythmias or the progression of heart failure, resulting in death. In adults, the QRS-T angle derived from ECG has been associated with adverse outcomes in patients with hypertrophic and dilated cardiomyopathies. We aimed to assess the electrocardiographic parameters, including QRS-T angle, associated with adverse cardiac events in children with cardiomyopathies. Forty-two children with cardiomyopathies were included in this study: 19 with dilated cardiomyopathy, 17 with hypertrophic cardiomyopathy, and 6 with left ventricular non-compaction. Additionally, 19 control subjects were recruited. In terms of ECG parameters, the QRS-T angle was significantly greater among patients with adverse outcomes compared to patients without the end points of the study (133° vs. 65°, p < 0.001). On Kaplan–Meier survival curves, QRS-T angle > 120°, increased serum concentrations of NT-proBNP and troponin I levels as well as greater NYHA or Ross scale were associated with the greatest risk of unfavorable outcome. The QRS-T angle appears to be a valuable component of 12-lead ECG interpretation, and might be helpful in outlining patients with the greatest cardiovascular risk. Additionally, serum biomarkers such as NT-proBNP (p = 0.003) and troponin (p < 0.001) are useful in outlining patients with the worst survival.

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Lower spatial QRS-T angle rules out sustained ventricular arrhythmias in children with hypertrophic cardiomyopathy

Abstract: In children with hypertrophic cardiomyopathy, the spatial peaks QRS-T angle is associated with ventricular arrhythmia burden with high negative predictive value and odds ratio.

Cited by 7 publications

References 26 publications

Intra-subject stability of different expressions of spatial QRS-T angle and their relationship to heart rate

Intra-subject stability of different expressions of spatial QRS-T angle and their relationship to heart rate

Quantitative T‐wave morphology assessment from surface ECG is linked with cardiac events risk in genotype‐positive KCNH2 mutation carriers with normal QTc values

Electrocardiographic Parameters Associated with Adverse Outcomes in Children with Cardiomyopathies

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