Isolated negative T waves in the general population is a powerful predicting factor of cardiac mortality and coronary heart disease

Prevalence of ECG abnormalities in people with type 2 diabetes: The Hoorn Diabetes Care System cohort

AIMS

The American Diabetes Association, and the joint European Society of Cardiology and European Association for the Study of Diabetes guidelines recommend a resting ECG in people with type 2 diabetes with hypertension or suspected cardiovascular disease (CVD). However, knowledge on the prevalence of ECG abnormalities is incomplete. We aimed to analyse the prevalence of ECG abnormalities and their cross-sectional associations with cardiovascular risk factors in people with type 2 diabetes.

METHODS

We used data of the Diabetes Care System cohort obtained in 2018. ECG abnormalities were defined using the Minnesota Classification and categorised into types of abnormalities. The prevalence was calculated for the total population (n = 8068) and the subgroup of people without a history of CVD (n = 6494). Logistic regression models were used to asses cross-sectional associations.

RESULTS

Approximately one-third of the total population had minor (16.0%) or major (13.1%) ECG abnormalities. Of the participants without a CVD history, approximately one-quarter had minor (14.9%) or major (9.1%) ECG abnormalities, and for those with hypertension or very high CVD risk, the prevalence was 27.5% and 39.6%, respectively. ECG abnormalities were significantly and consistently associated with established CVD risk factors.

CONCLUSIONS

Resting ECG abnormalities are common in all people with type 2 diabetes (29.1%), including those without a history of CVD (24.0%), and their prevalence is related to traditional cardiovascular risk factors such as older age, male sex, hypertension, lower HDL cholesterol, higher BMI, and smoking behaviour.

Prospective associations between ECG abnormalities and death or myocardial infarction in a cohort of 980 employed, middle-aged Swedish men

Background

In 1993, 1000 randomly selected employed Swedish men aged 45–50 years were invited to a nurse-led health examination with a survey on life style, fasting lab tests, and a 12-lead ECG. A repeat examination was offered in 1998. The ECGs were classified according to the Minnesota Code. Upon ethical approval, endpoints in terms of MI and death over 25 years were collected from Swedish national registers with the purpose of analyzing the independent association of ECG abnormalities as risk factors for myocardial infarction and death.

Results

Seventy-nine of 977 participants had at least one ECG abnormality 1993 or 1998.

One hundred participants had a first MI over the 25 years. Odds ratio for having an MI in the group that had one or more ECG abnormality compared with the group with two normal ECGs was estimated to 3.16. 95%CI (1.74; 5.73), p value 0.0001.

One hundred fifty-seven participants had died before 2019. For death, similarly no statistically significant difference was shown, OR 1.52, 95%CI (0.83; 2.76).

Conclusions

Our study suggests that presence of ST- and R-wave changes is associated with an independent 3–4-fold increased risk of MI after 25 years follow-up, but not of death. A 12-lead resting ECG should be included in any MI risk calculation on an individual level.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43044-020-00114-9.

Prevalence and long-term prognosis of patients with 'narrower than normal' QRS complexes

Aims

Very narrow QRS have been reported in sudden death survivors but prevalence and prognosis role of narrow QRS is unknown.

Methods and results

546 healthy men between 50 and 60 years (group 1) and 373 similar patients with coronary artery disease (368 men, group 2) underwent signal averaged ECG (SA-ECG) allowing precise measurement of QRS duration. All cause-mortality was determined after 18 ± 3 years follow-up. Mean QRS duration was 97 ± 13 ms in group 1 and 103 ± 16 ms in group 2. Tenth percentile was 84 ms in group 1 and 85 ms in group 2. All cause-mortality in group 1 was 10.4% (57/546): 6/85 in case of QRS <85 ms (7%) and 2/23 (9%) in case of QRS >120 ms (ns). HR for all-cause mortality was 0.75 (95% CI 0.32-1.76, P = 0.52) for QRS <85 ms and 0.86 (95% CI 0.21-3.53, P = 0.84) for QRS >120 ms. All cause mortality in group 2 was 29% (109/373): 7/44 in case of QRS <85 ms (16%) and 22/44 (50%) in case of QRS >120 ms (P = 0.002). HR for all-cause mortality was 0.65 (95% CI 0.29-1.45, P = 0.29) for QRS <85 ms and 1.73 (95% CI 1.02-2.94, P = 0.05) for QRS >120 ms.

Conclusion

QRS duration <80-85 ms can be observed in a significant proportion of middle-aged healthy males and in similar patients with ischemic heart disease. Narrow QRS were not linked to prognosis in any group.

Ischemic ECG abnormalities are associated with an increased risk for death among subjects with COPD, also among those without known heart disease

Abstract presentation

An abstract, including parts of the results, has been presented at an oral session at the European Respiratory Society International Conference, London, UK, September 2016.

Background

Cardiovascular comorbidity contributes to increased mortality among subjects with COPD. However, the prognostic value of ECG abnormalities in COPD has rarely been studied in population-based surveys.

Aim

To assess the impact of ischemic ECG abnormalities (I-ECG) on mortality among individuals with COPD, compared to subjects with normal lung function (NLF), in a population-based study.

Methods

During 2002–2004, all subjects with FEV₁/VC <0.70 (COPD, n=993) were identified from population-based cohorts, together with age- and sex-matched referents without COPD. Re-examination in 2005 included interview, spirometry, and 12-lead ECG in COPD (n=635) and referents [n=991, whereof 786 had NLF]. All ECGs were Minnesota-coded. Mortality data were collected until December 31, 2010.

Results

I-ECG was equally common in COPD and NLF. The 5-year cumulative mortality was higher among subjects with I-ECG in both groups (29.6% vs 10.6%, P<0.001 and 17.1% vs 6.6%, P<0.001). COPD, but not NLF, with I-ECG had increased risk for death assessed as the mortality risk ratio [95% confidence interval (CI)] when compared with NLF without I-ECG, 2.36 (1.45–3.85) and 1.65 (0.94–2.90) when adjusted for common confounders. When analyzed separately among the COPD cohort, the increased risk for death associated with I-ECG persisted after adjustment for FEV₁ % predicted, 1.89 (1.20–2.99). A majority of those with I-ECG had no previously reported heart disease (74.2% in NLF and 67.3% in COPD) and the pattern was similar among them.

Conclusion

I-ECG was associated with an increased risk for death in COPD, independent of common confounders and disease severity. I-ECG was of prognostic value also among those without previously known heart disease.