Prognostic implications of quantitative ST-segment characteristics and T-wave amplitude for cardiovascular mortality in a general population from the Health 2000 Survey

Association between T wave morphology parameters and abnormal cardiac SPECT imaging

BACKGROUND

T-wave morphology dispersion (TMD) described the electrocardiographic T-wave heterogeneity during a single cardiac cycle. Total cosine R-to-T (TCRT) is the average of the cosines of the angles between the QRS and T vectors on the ECG. We examine the predictive value of TMD and TCRT calculation to assess abnormal myocardial perfusion.

METHODS

Retrospective single center cohort study including all patients referred for evaluation of ischemia by myocardial SPECT scanning with no known history of ischemic heart disease, from 1 January 2019 to 31 December 2019. Study endpoint was the correlation between the calculated TMD and TCRT values and detection of myocardial injury or ischemia by myocardial SPECT.

RESULTS

Among 606 patients, calculated TCRT was 0.401 ± 0.53 for the normal group and 0.283 ± 0.62 for the abnormal group (p = 0.007). Measured TMD was 22.9 ± 16.6 degrees (p < 0.001) in the normal group, compared to 31.5 ± 22.8 degrees (p < 0.001) for the abnormal group.

CONCLUSIONS

The results demonstrate a correlation between the decreased TCRT values and increase TMD and myocardial ischemia seen in SPECT results. The TCRT and TMD can be used as simple and non-invasive markers to predict abnormal SPECT results and ischemic heart disease in patients with no known cardiac history.

The prognostic significance of T-wave inversion according to ECG lead group during long-term follow-up in the general population

Background

Inverted T waves in the electrocardiogram (ECG) have been associated with coronary heart disease (CHD) and mortality. The pathophysiology and prognostic significance of T‐wave inversion may differ between different anatomical lead groups, but scientific data related to this issue is scarce.

Methods

A representative sample of Finnish subjects (n = 6,354) aged over 30 years underwent a health examination including a 12‐lead ECG in the Health 2000 survey. ECGs with T‐wave inversions were divided into three anatomical lead groups (anterior, lateral, and inferior) and were compared to ECGs with no pathological T‐wave inversions in multivariable‐adjusted Fine–Gray and Cox regression hazard models using CHD and mortality as endpoints.

Results

The follow‐up for both CHD and mortality lasted approximately fifteen years (median value with interquartile ranges between 14.9 and 15.3). In multivariate‐adjusted models, anterior and lateral (but not inferior) T‐wave inversions associated with increased risk of CHD (HR: 2.37 [95% confidence interval 1.20–4.68] and 1.65 [1.27–2.15], respectively). In multivariable analyses, only lateral T‐wave inversions associated with increased risk of mortality in the entire study population (HR 1.51 [1.26–1.81]) as well as among individuals with no CHD at baseline (HR 1.59 [1.29–1.96]).

Conclusions

The prognostic information of inverted T waves differs between anatomical lead groups. T‐wave inversion in the anterior and lateral lead groups is independently associated with the risk of CHD, and lateral T‐wave inversion is also associated with increased risk of mortality. Inverted T wave in the inferior lead group proved to be a benign phenomenon.

Long-term prognostic significance of the ST level and ST slope in the 12‑lead ECG in the general population

BACKGROUND

Even minor ST depression in the electrocardiogram (ECG) is associated with cardiovascular disease and increased mortality. There is limited data on the prognostic significance of ST-level changes in the general population.

SUBJECTS AND METHODS

A random sample of Finnish subjects (n = 6354) aged over 30 years (56.1% women) underwent a health examination including a 12‑lead ECG in the Health 2000 survey. The effects of relative ST level as a continuous variable and ST slope (upsloping, horizontal, downsloping) in three different lead groups were analyzed using a multi-adjusted Cox proportional hazard model separately for men and women with total mortality as endpoint.

RESULTS

The follow-up lasted for 13.7 (SD 3.3) years for men and 13.9 (SD 3.1) years for women. Lower lateral ST levels were associated with all-cause mortality in multi-adjusted models in both genders (at J + 80 ms hazard ratio [HR] 0.64 for a change of 1.0 mm [95% confidence interval 0.49-0.84, p = 0.002] for men and HR 0.61 [0.48-0.78, p < 0.001] for women). Associated coronary heart disease had no major influence on the results. Exclusion of subjects with ECG signs of left ventricular hypertrophy from the analyses increased the mortality risk of lower lateral ST levels in men but decreased it in women. For the anterior and inferior lead groups, no statistically significant difference was seen after multivariate adjustment. ST slope was not an independent predictor of mortality after multivariate adjustment.

CONCLUSION

Lower ST level in the lateral ECG leads is an independent prognostic factor to predict all-cause mortality in the general population.

Relationships of electrocardiographic parameters with ambulatory hypertension in young and healthy adults

BACKGROUND

Elevated blood pressure (BP) is a leading cardiovascular risk factor and a major determinant of left ventricular mass. Te aim of this study was to assess electrocardiographic (ECG) changes associated with hypertension in a large cohort of young and healthy adults.

METHODS

Healthy individuals aged 25–41 years without known cardiovascular disease were enrolled in a population based cohort study. Resting 12-lead ECG and ambulatory 24-hour BP measurement were obtained using validated devices. Multivariable logistic regression models were constructed to assess the relationships between ECG parameters and daytime hypertension, defined as systolic daytime BP≥140, diastolic BP≥90 mmHg or use of antihypertensive treatment.

RESULTS

Daytime hypertension was present among 430 of 2070 (21%) participants. Significant linear relationships were observed between daytime hypertension with RR interval (odds ratio (OR) 95% confidence interval (CI) 0.84 (0.78; 0.92)), R-wave amplitude in leads I and II (OR (95% CI) 2.04 (1.30; 3.19) and 1.61 (1.15; 2.24), and S-wave amplitudes in leads aVR, V1 and V2 with ORs (95% CI) of 3.28 (1.93; 5.59), 2.15 (1.51; 3.08) and 1.47 (1.18; 1.83), respectively. We also observed linear associations between daytime hypertension and T-wave amplitudes in leads V1 (OR (95% CI) 4.83 (2.35; 9.91)), V2 (2.18 (1.43; 3.32)), V4 (0.48 (0.29; 0.80)) and V5 (0.37 (0.19; 0.72)).

CONCLUSION

Several ECG parameters are independently associated with daytime hypertension among young and healthy adults. This is one of the first studies to show significant relationships between T wave amplitude and hypertension.

The prognostic value of positive T-wave in lead aVR in hemodialysis patients

BACKGROUND

Given that cardiac disease is the leading cause of mortality in hemodialysis (HD) patients, identification of patients at risk for cardiac mortality is crucial. The aim of this study was to determine if positive T-wave amplitude in lead aVR (TaVR) was predictive of cardiovascular (CV) mortality and sudden cardiac death (SCD) in a group of HD patients.

METHODS AND RESULTS

After exclusion, 223 HD patients were prospectively followed-up for 25.43 ± 3.56 months. Patients were divided into TaVR negative (n = 186) and TaVR positive (n = 37) groups. Myocardial infarction, diabetes and beta-blocker therapy were more frequent in positive TaVR patients. Patients with upright TaVR were older, had higher left ventricular mass index, lower ejection fraction, higher calcium × phosphate product, higher troponin T level, higher prevalence of ST-T abnormalities, and increased width of QRS complex and QT interval, compared with patients with negative TaVR. A Kaplan-Meier analysis showed that the cumulative incidences of CV mortality as well as SCD were higher in patients with positive TaVR compared with those with negative TaVR (log-rank, p < 0.001 in both cases). A multivariate analysis selected age [hazard ratio (HR) 1.71, p < 0.001], heart rate (HR 1.42, p = 0.016), and positive TaVR (HR 2.21, p = 0.001) as well as age (HR 1.88, p < 0.001), and positive TaVR (HR 1.53, p = 0.014) as independent predictors of CV mortality and SCD, respectively.

CONCLUSION

In HD patients, positive TaVR is an independent and powerful predictor of CV mortality as well as SCD. This simple ECG parameter provides additional information beyond what is available with other known traditional risk factors and allows the identification of patients most at risk of CV events.

T-wave inversion and mortality risk

OBJECTIVE

To investigate the predictive value of T-wave inversion (TWI) on routine electrocardiogram (ECG) for mortality in the general population with various risk groups in a prospective population-based follow-up study. Subjects. ECGs of a random population-based sample of 1814 men aged 42-60 years without coronary heart disease (CHD) at baseline.

RESULTS

During an average follow-up of 21 years, 685 deaths occurred. Of these deaths 174 were due to CHD and 278 to cardiovascular disease (CVD). There were 57 subjects with TWI. After adjusting for age, TWI was associated with an increased CHD mortality (relative risk (RR) 4.10, 95% CI 2.26-7.41), CVD mortality (RR 3.47, 95% CI 2.09-5.78), and all-cause mortality (RR 2.07, 95% CI 1.37-3.12). After further adjustment for conventional risk factors, TWI remained statistically significant, predicting CHD mortality (RR 2.62, 95% CI 1.57-4.36), CVD mortality (RR 2.18, 95% CI 1.40-3.38), and all-cause mortality (RR 1.41, 95% CI 1.00-2.01), respectively.

CONCLUSION

TWI is a strong predictor for CHD, CVD, and all-cause mortality in the general population. The respective risks of CHD and CVD among men with TWI were also increased among men with high blood pressure, LDL cholesterol, and obesity.

Relation of positive T wave in lead aVR to risk of cardiovascular mortality

We examined the prevalence and prognostic impact of a positive T wave in lead aVR (aVRT+) on a standard electrocardiogram in the general population. Data were collected from a large nationally representative (random sample) health examination survey conducted in Finland from 2000 through 2001. The survey consisted of 6,354 subjects (2,876 men and 3,478 women) ≥30 years who participated in the field health examination including standard electrocardiographic (ECG) recording at rest. The prevalence of aVRT+ (defined as positive or isoelectric T wave in lead aVR) was 2.2%. During the median follow-up of 98.5 months (interquartile range 96.6 to 99.6), there were 214 (3.5%) cardiovascular (CV) deaths. In Cox regression analysis after adjustment for age and gender, relative risks for CV and total mortalities associated with aVRT+ were 3.24 (95% confidence interval [CI] 2.32 to 4.54, p <0.001) and 1.91 (95% CI 1.47 to 2.49, p <0.001), respectively. In the fully adjusted model controlling for other risk factors, CV morbidity, and ECG findings, the relative risk for CV mortality for aVRT+ was 2.94 (95% CI 2.07 to 4.18, p <0.001). In conclusion, aVRT+, an easily recognized ECG finding, predicts risk for CV mortality in the general population. This finding could aid in screening for risk of total and CV mortalities.