A large frontal QRS-T angle is a strong predictor of the long-term risk of myocardial infarction and all-cause mortality in the diabetic population

doi:10.1016/j.jdiacomp.2016.12.001

Journal of Diabetes and its Complications

Volume 31, Issue 3, March 2017, Pages 551-555

https://doi.org/10.1016/j.jdiacomp.2016.12.001 Get rights and content

Abstract

Background

A large angle between the QRS vector and the T-wave vector (QRS-T angle) in electrocardiograms (ECGs) has recently been introduced as a marker of poor prognosis. The prognostic value in diabetes is unknown. We assessed the long-term predictive power of the frontal plane QRS-T angle in the diabetic population.

Methods

In 1992–93, the diabetic population of the municipality of Horsens, Denmark, was delineated by the prescription method, and an age- and gender-stratified sample of 240 diabetic persons was randomly selected. In 2015, 12-lead ECGs taken in 1993–94 were analyzed. Vital statistics were obtained from the Danish Civil Registration System and data regarding hospitalizations taken from The National Patient Registry in July 2015.

Results

In total, 178 people agreed to participate (74%) in the study, with the mean (sd) age being 58.9 (10.2) years and 56% being male. The total observation time was 21.5 (0.18) years, during which time 122 (69%) persons died, 32 (18%) suffered a myocardial infarction (MI) and 126 (71%) reached the composite endpoint of non-fatal MI or all-cause death.

In Cox regression multivariate analysis a QRS-T angle above 90° was found to be an independent predictor of all-cause death (HR = 2.2 (95% CI: 1.3–3.8)), MI (HR = 2.95 (95% CI: 1.1–7.7)) and MI or all-cause death (HR = 2.0 (95% CI: 1.2–3.5)) (all p < 0.05), when adjusting for the effects of co-variates (gender, age, length of diabetes, BMI, total cholesterol, diabetes type, hemoglobin A1c, smoking, hypertension and previous MI).

Conclusion

A large QRS-T angle is a strong, independent long-term predictor of all-cause mortality, MI and MI or all-cause death in the diabetic population.

Introduction

The risk of cardiovascular disease and death is significantly higher in the diabetic population compared to the non-diabetic population (Leland & Maki, 1985). Although several factors are known to be related to adverse outcomes in diabetes, strong predictors of risk are still requested, in order to be able to focus on diabetic individuals in extra need of intensive treatment.

The angle between the mean vector in left ventricular depolarization and repolarization (QRS-T angle) has recently been introduced as a marker of poor prognosis. The QRS-T angle may be measured in the three-dimensional space or as a projection on the frontal plane in a standard electrocardiogram (ECG) (Oehler, Feldman, Henrikson, & Tereshchenko, 2014). Although the spatial QRS-T angle may be the stronger predictor of a poor outcome compared to its frontal plane counterpart (Brown & Schlegel, 2011), the latter has been shown to predict total mortality in the general population (Aro et al., 2012, Zhang et al., 2015), in cardiomyopathy (Pavri et al., 2008), in congestive heart failure (Gotsman et al., 2013) and in acute coronary syndrome (Lown et al., 2012). Contrary to the spatial QRS-T angle, the frontal QRS-T angle is easily read from a standard ECG. It is well-known that the QRS-T angle differs according to age and gender (Oehler et al., 2014), but for pragmatic reasons 90° is often used as a cut-off between a normal and an abnormal result (Gandhi et al., 2010, Li et al., 2013, Palaniswamy et al., 2009, Pavri et al., 2008).

An increased spatial QRS-T angle has been related to the presence of diabetes (Voulgari et al., 2006), and in diabetic patients the frontal plane QRS-T angle has been associated with other adverse outcome factors in a cross-sectional study (Cardoso, Leite, & Salles, 2013). The prognostic value of the frontal plane QRS-T angle in the diabetic population is unknown.

The purpose of this study was to assess the long-term predictive value of the frontal plane QRS-T angle in the diabetic population on all-cause mortality, myocardial infarction (MI) and MI or all-cause death. The aim was to investigate the value of the QRS-T angle as a continuous variable as well as when dichotomized at 90°. In addition, we wanted to examine the predictive information of the QRS-T angle in values below 90°.

Section snippets

Methods

The study was carried out in a population-based sample of medically treated diabetic individuals drawn from the population in the municipally of Horsens, Denmark, in 1993–1994. The material has previously been described in detail (May, Arildsen, Damsgaard, & Mickley, 1997). In brief, the diabetic part of the population in the municipality was delineated from information on all prescriptions for anti-diabetic medication over an eight-month period from November 1st, 1992 until June 30th, 1993. In

Results

In total, 178 patients (74% of those invited) agreed to participate, with males accounting for 56% of the cohort and a mean age of 58.9 (10.2) years. The patients included were significantly younger than the non-responders, with males at 47% and a mean age of 61.9 (10.4) years (p = 0.049). The groups did not differ in gender (p = 0.20).

The mean QRS-T angle was 38° (39°), and 18 patients (10%) had a QRS-T angle above 90°. Twenty-five patients (14%) had an abnormal QRS-T angle which was associated

Discussion

This is the first study to report on the long-term prognostic value of the QRS-T angle in diabetes. We found that the a QRS-T angle above 90° was a powerful independent prognostic factor for future all-cause mortality as well as MI and the composite endpoint MI or all-cause death. The estimated overall survival times were 2.4 times longer in the group with a QRS-T angle below 90° compared to patients with an angle above 90°.

The QRS-T angle in our study of patients with diabetes had a mean of

Limitations of the study

The cohort examined may not be exactly representative of the diabetic population today, but this is an unavoidable problem in long-term studies. Furthermore, only medically treated individuals with diabetes were included. The prognosis may be better in diabetes treated by diet only, and so the negative prognostic value of the QRS-T angle found in this study may thus differ from the prognosis in diabetes treated by diet alone. Additionally, the prognosis in the group studied herein may be better

Conclusion

A large QRS-T angle is a strong long-term predictor of all-cause mortality and myocardial infarction in the diabetic population. Values of QRS-T angles below 90° also seem to hold predictive information.

Funding

None.

References (19)

R.A. Brown et al.
Diagnostic utility of the spatial versus individual planar QRS-T angles in cardiac disease detection
Journal of Electrocardiology
(2011)
I. Gotsman et al.
Usefulness of electrocardiographic frontal QRS-T angle to predict increased morbidity and mortality in patients with chronic heart failure
The American Journal of Cardiology
(2013)
M.T. Lown et al.
Association of frontal QRS-T angle–age risk score on admission electrocardiogram with mortality in patients admitted with an acute coronary syndrome
The American Journal of Cardiology
(2012)
Z.M. Zhang et al.
Comparison of the prognostic significance of the electrocardiographic QRS/T angles in predicting incident coronary heart disease and total mortality (from the Atherosclerosis Risk in Communities study)
The American Journal of Cardiology
(2007)
A.L. Aro et al.
QRS-T angle as a predictor of sudden cardiac death in a middle-aged general population
Europace
(2012)
C.J. Borleffs et al.
Predicting ventricular arrhythmias in patients with ischemic heart disease: Clinical application of the ECG-derived QRS-T angle
Circulation. Arrhythmia and Electrophysiology
(2009)
C.R. Cardoso et al.
Factors associated with abnormal T-wave axis and increased QRS-T angle in type 2 diabetes
Acta Diabetologica
(2013)
A. Erlangsen et al.
Danish nationwide registers for public health and health-related research
Scandinavian Journal of Public Health
(2015)
K. Gandhi et al.
Patients with ischemic stroke have a higher prevalence of a planar QRS-T angle > 90 degrees than patients with transient ischemic attack
Medical Science Monitor
(2010)

There are more references available in the full text version of this article.

Cited by (23)

The effect of dapagliflozin therapy on ventricular repolarization parameters in electrocardiography in patients with diabetic cardiovascular disease
2023, Journal of Diabetes and its Complications
Dapagliflozin is an agent that has both antihyperglycemic effects and is significantly associated with a lower risk of cardiovascular events in patients with diabetes mellitus (DM). However, there is insufficient data and information about the effect of dapagliflozin on electrocardiographic (ECG) parameters.
The effects of dapagliflozin on ventricular repolarization parameters have not been fully elucidated yet. This study aimed to investigate whether dapagliflozin has a positive effect on ventricular repolarization heterogeneity parameters in patients with type 2 DM.
We retrospectively enrolled 140 patients with a known diagnosis of type 2 DM who were newly prescribed dapagliflozin in addition to standard anti-diabetic therapy. The patients were divided into two groups according to whether they had cardiovascular disease (CVD). The effect of dapagliflozin treatment on ventricular repolarization parameters (frontal plane QRST angle, Tp-e interval, Tp-e/QTc, QTc, and QTc dispersion) was investigated, patient groups were compared before and after treatment.
Among 140 patients, 70 (50 %) had CVD and 70 (50 %) did not have CVD. Dapagliflozin treatment resulted in significant reductions in ventricular repolarization parameters over the study period in the CVD group with diabetes. Mean fQRST angle, Tp-e interval, Tp-e/QTc, QTc, and QTc dispersion were significantly lower than baseline values at 6-month follow-up visits in the CVD group (61.61 ± 9.22^° vs 52.55 ± 8.31^°, 74.45 ± 16.06 msec vs 63.27 ± 13.99 msec, 0.19 ± 0.03 vs 0.16 ± 0.03, 384.12 ± 47.93 msec vs 356.15 ± 43.31 mesc, 55.28 ± 5.50 msec vs 48.08 ± 6.48 msec for all pairwise comparisons p < 0.001).
Similar antihyperglycemic effects were found with dapagliflozin treatment in patients with and without CVD. However, significant reductions in ventricular repolarization parameters were observed only in patients with CVD.
Functional consequences of lead and mercury exposomes in the heart
2022, Molecular Aspects of Medicine
Citation Excerpt :
These latter studies report a Pb2+-mediated prolongation in the QT interval (Chen et al., 2013 Kiełtucki et al., 2017) and alterations in the QRS-T angle (Jing et al., 2019). Both events are associated with arrhythmias and sudden cardiac death (Anderson, 2006; Bergfeldt et al., 2020; May et al., 2017; Schwartz and Wolf, 1978). Prolonged conduction between atria and ventricle (P-R interval prolongation) has also been reported, among other conduction disturbances that can develop into cardiac arrhythmias (Cheng et al., 1998; Myerson and Eisenhauer, 1963).
Lead and mercury are heavy metals that are highly toxic to life forms. There are no known physiological processes that require them, and they do not have a particular threshold concentration to produce biologic damage. They are non-biodegradable, and they slowly accumulate in the environment in a dynamic equilibrium between air, water, soil, food, and living organisms. Their accumulation in the environment has been increasing over time, because they were not banned from use in anthropogenic industrial production. In their +2 cationic state they are powerful oxidizing agents with the ability to interfere significantly with processes that require specific divalent cations. Acute or chronic exposure to lead and mercury can produce multisystemic damage, especially in the developing nervous systems of children and fetuses, resulting in variety of neurological consequences. They can also affect the cardiovascular system and especially the heart, either directly through their action on cardiomyocytes or indirectly through their effects on innervation, humoral responses or blood vessel alterations. For example, heart function modified by these heavy metals are heart rate, contraction, excitability, and rhythm. Some cardiac molecular targets have been identified and characterized. The direct mechanisms of damage of these heavy metals on heart function are discussed. We conclude that exposome to these heavy metals, should be considered as a major relevant risk factor for cardiac diseases.
Frontal QRS/T angle can predict mortality in COVID-19 patients
2022, American Journal of Emergency Medicine
Citation Excerpt :
We split the patients into two groups according to the fQRS angle (>90° versus ≤90°). The fQRs >90° group was labelled as wide and fQRS ≤90° group as narrow, as an fQRs >90° was reportedly a significant predictor of mortality in many studies, including the DEFINITE trial [10,11]. The demographic characteristics of all patients reported with the values of weight, height, body mass index, standard blood testing including d-dimer, troponin I (cTnI), C-reactive protein (CRP), estimated glomerular filtration rate (eGFR), lymphocyte count, neutrophil count, and lymphocyte-to-neutrophil ratio as well as computed tomography, oxygen saturation (SO2), at the time of admission.
The frontal QRS-T (fQRS) angle has been investigated in the general population, including healthy people and patients with heart failure. The fQRS angle can predict mortality due to myocarditis, ischaemic and non-ischaemic cardiomyopathies, idiopathic dilated cardiomyopathy, and chronic heart failure in the general population. Moreover, no studies to date have investigated fQRS angle in coronavirus disease 2019 (COVID-19) patients. Thus, the purpose of this retrospective multicentre study was to evaluate the fQRS angle of COVID-19 patients to predict in-hospital mortality and the need for mechanical ventilation.
An electrocardiogram was performed for 327 COVID-19 patients during admission, and the fQRS angle was calculated. Mechanical ventilation was needed in 119 patients; of them, 110 died in the hospital. The patients were divided into two groups according to an fQRs angle >90° versus an fQRS angle ≤90°. The percentages of mortality and the need for mechanical ventilation according to fQRS angle were 67.8% and 66.1%, respectively, in the fQRs >90° group and 26.1% and 29.9% in the fQRS ≤90°group. Heart rate, oxygen saturation, fQRS angle, estimated glomerular filtration rate, and C-reactive protein level were predictors of mortality on the multivariable analysis. The mortality risk increased 2.9-fold on the univariate analysis and 1.6-fold on the multivariate analysis for the fQRS >90° patient group versus the fQRS ≤90° group.
In conclusion, a wide fQRS angle >90° was a predictor of in-hospital mortality and associated with the need for mechanical ventilation among COVID-19 patients.
Frontal QRS-T angle and World Health Organization classification for body mass index
2018, International Journal of Cardiology
Citation Excerpt :
QRS axis and T-wave axis were automatically measured. According to previous reports [2–5,11–13], frontal QRS-T angle was defined as the absolute value of the difference between the frontal plane QRS axis and T-wave axis. When QRS-T angle was >180°, it was adjusted to the minimal angle using (360° - angle).
The frontal QRS-T angle, defined as the absolute value of the difference between QRS axis and T-wave axis on 12‑lead electrocardiogram (ECG), is the difference in orientation between ventricular depolarization and repolarization. We tested the hypothesis that QRS-T angle is affected by obesity.
A total of 177 patients undergoing both ECG and echocardiography within one month were recruited from outpatient clinic. Using the World Health Organization (WHO) classification of body mass index (BMI), the patients were classified into the four groups: underweight (<18.5 kg/m², n = 25), normal weight (18.5–24.9 kg/m², n = 79), overweight (25–29.9 kg/m², n = 38) and obese (≥30 kg/m², n = 35).
Obese patients were significantly younger than those in other groups. As for echocardiographic variables, left ventricular internal dimension and left ventricular mass (LVM) increased with increased WHO classification of BMI. QRS axis and T-wave axis decreased with increased WHO classification of BMI, whereas QRS-T angle increased. Multivariate linear regression analysis showed that BMI (β = 0.23, p = 0.01) and LVM (β = 0.19, p = 0.046) were independent determinants of QRS-T angle.
Our results suggest that BMI is an independent determinant of QRS-T angle.
Spatial peak and mean QRS-T angles: A comparison of similar but different emerging risk factors for cardiac death
2020, Journal of Electrocardiology
Citation Excerpt :
Identification of more efficient risk markers, which alone or in combination, can be used for selecting patients suitable for ICD therapy and thereby preventing cardiac arrest and SCD therefore remains an important research goal. Abnormal QRS-T angles are scientifically but not clinically established risk factors for cardiovascular events including SCD [6–17]. They define the relation between the dominating ventricular depolarization (QRS) and repolarization (T) forces, and their assessment is one reason for the increasing interest in a vectorcardiographic approach to electrocardiology [18].
The spatial peak and mean QRS-T angles are scientifically but not clinically established risk factors for cardiovascular events including cardiac death. The study aims were to compare these angles, assess their association with hypertension (HT) and diabetes mellitus (DM), and explore the relation between the mean QRS-T angle and the ventricular gradient (VG; reflecting electrical heterogeneity), which both are derived from the QRSarea and Tarea vectors.
Altogether 1094 participants (aged 50–65 years, 550 women) from the pilot of the population-based Swedish CArdioPulmonary bioImage Study with Frank vectorcardiographic recordings were included and divided into 5 subgroups: apparently healthy n = 320; HT n = 311; DM n = 33; DM + HT n = 53; miscellaneous conditions n = 377. Abnormal peak and mean QRS-T angles were defined as >95th percentile.
Peak QRS-T angles were generally narrower than the mean QRS-T angles; both were narrower in women than in men. Abnormal peak (>124°) and/or mean (>119°) QRS-T angles were found in 73 participants (6.7%). The concordance regarding abnormal versus normal-borderline QRS-T angles was good (Cohen's kappa 0.61). The prevalence of abnormal angles varied from 2.5% in healthy to 21.2% in DM. There was an inverse logarithmical relation between the mean QRS-T angle and the VG.
The peak and mean QRS-T angles are not interchangeable but complementary. DM, HT, sex and absence of disease are important determinants of both QRS-T angles. The mean QRS-T angle and the VG relationship is complex. All three VCG derived measures reflect related but differing electrophysiological properties and have potential prognostic value vis-à-vis cardiovascular events.
Frontal QRS-T angle predicts coronary atherosclerotic burden in patients with ST segment elevation myocardial infarction
2020, Journal of Electrocardiology
Citation Excerpt :
Residual SYNTAX score > 8 was also significantly associated with post-procedural fQRST angle [68 (3–163) vs. 89 (6–183), p < 0.001] (Table 2). Frontal QRS-T angle values were also classified into two groups (narrow and wide) based on a cut-off value, where 90° was generally accepted as a cut-off between a normal and an abnormal result [13]. In consensus with the previous findings, the cut-off value of fQRST angle for pre-procedural SYNTAX score was determined to be 91° as a result of ROC curve analysis [54.8% sensitivity and 74.2% specificity, the area under curve: 0.582, p = 0.015, 95% CI (0.515–0.650)].
Frontal QRS-T (fQRST) angle is an electrocardiogram (ECG)-derived marker, indicating the concordance between ventricle depolarization and repolarization. A wide fQRST angle has been found to be associated with cardiovascular mortality. The authors aim to investigate the relationship between fQRST angle and the extent and severity of coronary artery disease in patients with ST-segment elevation myocardial infarction (STEMI).
Three hundred and forty patients presenting with STEMI were enrolled in the study. SYNTAX, SYNTAX II, and residual SYNTAX scores were calculated. The patients were categorized into two groups in terms of SYNTAX score: Low (SYNTAX score < 23) and intermediate-high score (SYNTAX score ≥ 23). SYNTAX II score was also classified as low and intermediate-high score. Residual SYNTAX score > 8 was evaluated as high score.
104 patients had SYNTAX score ≥ 23. Age (p = 0.001), peripheral arterial disease (p = 0.006), infarct-related artery (p = 0.001), and fQRST angle (p = 0.015) were significantly higher in intermediate-high SYNTAX group, while the values for left ventricle ejection fraction (p < 0.001) and hemoglobin level (p = 0.036) were found to be lower in this group. Pre- and post-procedural fQRST angle was higher in patients with SYNTAX II score > 21.9 and residual SYNTAX >8, respectively. The cut-off levels for fQRST angle established according to ROC analysis in terms of SYNTAX, SYNTAX II, and residual SYNTAX were found to be 91°, 76.5°, and 79.5° respectively. In multivariate analysis, fQRST angle, infarct-related artery, and age were independent predictors of intermediate-high SYNTAX score.
fQRST angle is an independent predictor of coronary atherosclerotic burden in STEMI patients.

View all citing articles on Scopus

: Conflicts of Interest: Nothing to declare.

View full text

A large frontal QRS-T angle is a strong predictor of the long-term risk of myocardial infarction and all-cause mortality in the diabetic population

Abstract

Background

Methods

Results

Conclusion

Introduction

Section snippets

Methods

Results

Discussion

Limitations of the study

Conclusion

Funding

Journal of Electrocardiology

The American Journal of Cardiology

The American Journal of Cardiology

The American Journal of Cardiology

QRS-T angle as a predictor of sudden cardiac death in a middle-aged general population

Europace

Predicting ventricular arrhythmias in patients with ischemic heart disease: Clinical application of the ECG-derived QRS-T angle

Circulation. Arrhythmia and Electrophysiology

Factors associated with abnormal T-wave axis and increased QRS-T angle in type 2 diabetes

Acta Diabetologica

Danish nationwide registers for public health and health-related research

Scandinavian Journal of Public Health

Patients with ischemic stroke have a higher prevalence of a planar QRS-T angle > 90 degrees than patients with transient ischemic attack

Medical Science Monitor