Prevalence, prognosis, and implications of isolated minor nonspecific ST-segment and T-wave abnormalities in older adults: Cardiovascular Health Study

Sex differences in the association between minor nonspecific ST-segment and T-wave abnormalities and coronary artery calcification

BACKGROUND AND AIMS

Although minor nonspecific ST-segment and T-wave abnormalities (NSSTTA) have been associated with adverse cardiovascular outcomes, their relationship with subclinical atherosclerosis remains controversial. Therefore, the associations between electrocardiographic (ECG) abnormalities, including NSSTTA, and coronary artery calcification (CAC) were investigated in this study.

METHODS

This cross-sectional study included 136,461 Korean participants with no known cardiovascular disease or cancer, who underwent a health checkup including ECG and computed tomography to measure the coronary artery calcium score (CACS) by Agatston method between 2010 and 2018. ECG abnormalities were defined in accordance with the Minnesota Code using an automated ECG analysis program. A multinomial logistic regression model was used to calculate prevalence ratios (PRs) with 95% confidence intervals (CI) for each CACS category.

RESULTS

In men, both NSSTTA and major ECG abnormalities were associated with all levels of CACS. The multivariable-adjusted PRs (95% CI) for CACS >400 comparing NSSTTA and major ECG abnormalities to the reference (neither NSSTTA nor major ECG abnormalities) were 1.88 (1.29-2.74) and 1.50 (1.18-1.91), respectively. Women with major ECG abnormalities were more likely to have a CACS of 101-400, the PRs (95% CI) comparing major ECG abnormalities to the reference group was 1.75 (1.18-2.57). NSSTTA were not associated with any CACS level in women.

CONCLUSIONS

NSSTTA and major ECG abnormalities are associated with CAC in men, though NSSTTA were not associated with CAC in women, suggesting that NSSTTA should be considered sex-specific risk factors for coronary artery disease in men, but not in women.

T-Wave Analysis on the 24 h Holter ECG Monitoring as a Predictive Assessment of Major Adverse Cardiovascular Events in Patients with Myocardial Infarction: A Literature Review and Future Perspectives

Myocardial ischemia is a pathophysiological state characterized by inadequate perfusion of the myocardium, resulting in an imbalance between myocardial oxygen demand and supply. It is most commonly caused by coronary artery disease, in which atherosclerotic plaques lead to luminal narrowing and reduced blood flow to the heart. Myocardial ischemia can manifest as angina pectoris or silent myocardial ischemia and can progress to myocardial infarction or heart failure if left untreated. Diagnosis of myocardial ischemia typically involves a combination of clinical evaluation, electrocardiography and imaging studies. Electrocardiographic parameters, as assessed by 24 h Holter ECG monitoring, can predict the occurrence of major adverse cardiovascular events in patients with myocardial ischemia, independent of other risk factors. The T-waves in patients with myocardial ischemia have prognostic value for predicting major adverse cardiovascular events, and their electrophysiological heterogeneity can be visualized using various techniques. Combining the electrocardiographic findings with the assessment of myocardial substrate may offer a better picture of the factors that can contribute to cardiovascular death.

The global prevalence of myocardial infarction: a systematic review and meta-analysis

BACKGROUND

Myocardial infarction (MI) is one of the life-threatening coronary-associated pathologies characterized by sudden cardiac death. The provision of complete insight into MI complications along with designing a preventive program against MI seems necessary.

METHODS

Various databases (PubMed, Web of Science, ScienceDirect, Scopus, Embase, and Google scholar search engine) were hired for comprehensive searching. The keywords of "Prevalence", "Outbreak", "Burden", "Myocardial Infarction", "Myocardial Infarct", and "Heart Attack" were hired with no time/language restrictions. Collected data were imported into the information management software (EndNote v.8x). Also, citations of all relevant articles were screened manually. The search was updated on 2022.9.13 prior to the publication.

RESULTS

Twenty-two eligible studies with a sample size of 2,982,6717 individuals (< 60 years) were included for data analysis. The global prevalence of MI in individuals < 60 years was found 3.8%. Also, following the assessment of 20 eligible investigations with a sample size of 5,071,185 individuals (> 60 years), this value was detected at 9.5%.

CONCLUSION

Due to the accelerated rate of MI prevalence in older ages, precise attention by patients regarding the complications of MI seems critical. Thus, determination of preventive planning along with the application of safe treatment methods is critical.

Longitudinal association of ECG abnormalities with major adverse cardiac events in people with type 2 diabetes: The Hoorn Diabetes Care System cohort

AIMS

To investigate the association of (changes in) ECG abnormalities with incident major adverse cardiac events (MACE) in people with type 2 diabetes (T2D) without pre-existing cardiovascular disease (CVD).

METHODS

A prospective longitudinal study of 11,993 people with T2D without known CVD from the Hoorn Diabetes Care System cohort. Annually repeated measurements (1998-2018), included cardiovascular risk factors, over 70,000 ECGs, and self-reported cardiovascular events. ECG abnormalities were classified according to the Minnesota Classification as prolonged PR duration, prolonged QRS duration, left QRS-axis, QS pattern, ST-segment/T-wave abnormalities, or tall R-wave. The association of ECG abnormalities with MACEs was assessed using time-dependent Cox-regression models, adjusted for time-varying cardiovascular risk factors and medication use (Hazzard Ratios with 95%CIs).

RESULTS

During a median follow-up of 6.6 (IQR, 3.1-10.7) years, 5445 (45.4%) of the participants had an ECG abnormality (prevalent or incident) at any of the median 6 (IQR, 3-10) annual ECG recordings, and 905 people (7.5%) had a MACE (529 CHD, 250 HF, 126 SCA). After adjustment, most ECG abnormalities were associated with HF: prolonged QRS duration (HR, 4.01 (95%CI, 2.67-6.03)), QS pattern (2.68 (0.85-8.49)), ST-segment/T-wave abnormalities (4.26 (2.67-6.80)), and tall R-wave (2.23 (1.33-3.76)). Only QS pattern (2.69 (1.20-6.03)), and ST-segment/T-wave abnormalities (2.11 (1.48-3.02)) were associated with CHD. These associations were robust across age, sex, hypertension, or estimated CVD risk subgroups.

CONCLUSION

In people with T2D without pre-existing cardiovascular disease, ECG abnormalities related to decelerated conduction, ischemia and hypertrophy are predominantly early signs of emerging HF, while only abnormalities related to ischemic disorders are signs of CHD.

Non-specific electrocardiographic ST-T abnormalities predict mortality in patients on peritoneal dialysis

Background

This study aimed to evaluate the predictive value of non-specific ST-segment and/or T-wave abnormalities in electrocardiography (ECG) for all-cause and cardiovascular mortality (CVM) in peritoneal dialysis (PD) patients.

Methods

All patients who started PD between November 1, 2005, and February 28, 2017, at the First Affiliated Hospital of Nanchang University were enrolled. The primary outcomes were all-cause mortality and CVM. The Kaplan-Meier method and a log-rank test were used for the survival analysis. Multivariate Cox proportional hazards models were used to investigate the risk factors for all-cause mortality and CVM.

Results

A total of 724 eligible PD patients were enrolled, including 401 (55.4%) men. In total, 153 (21.1%) patients died during a mean follow-up period of 27 (interquartile range, 13-41) months, and cardiovascular death was responsible for 84 of these deaths. The patients with non-specific ST-T abnormalities (NSSTTAs) had lower overall and cardiovascular survival rates compared to those free from any ECG abnormalities. According to the multivariate Cox proportional hazards models, (NSSTTAs) are independent risk factors for all-cause mortality and CVM, the hazard ratios are 1.81 (95% confidence interval, 1.11-2.95; p = 0.017) and 2.86 (95% confidence interval, 1.52-5.37; p = 0.001), respectively.

Conclusion

Non-specific ST-T abnormalities can serve as risk markers of all-cause and CVM in PD patients.

Nonspecific ventricular repolarization abnormalities: A wolf in sheep's clothing

The term nonspecific ventricular repolarization abnormalities refers to a set of minor alterations of the ST segment and/or the T wave. For a long time, they have been of little clinical interest as they do not translate into specific diagnoses. It has even been asserted that they constitute benign electrocardiographic findings. Their presence has been reported in various cardiovascular and non-cardiovascular diseases. However, it is frequently identified in apparently healthy asymptomatic people. A growing number of studies demonstrate their importance as predictors of cardiovascular morbidity and mortality, expanding their spectrum towards cardiovascular prevention. In light of the body of scientific evidence, it is imperative that the traditional view of nonspecific ventricular repolarization abnormalities changes.

The prognostic implications of ST-segment and T-wave abnormalities in patients undergoing regadenoson stress SPECT myocardial perfusion imaging

BACKGROUND

The prognostic implications of ST-segment and T-wave (ST/T) abnormalities in patients undergoing stress SPECT-myocardial perfusion imaging (MPI) are not well defined.

METHODS AND RESULTS

This was a single-center, retrospective cohort study of consecutive patients who underwent regadenoson stress SPECT-MPI. Patients with baseline electrocardiogram (ECG) abnormalities that impede ST/T analysis or those with known coronary artery disease were excluded. Patients were categorized as having primary ST abnormalities, secondary ST/T abnormalities due to ventricular hypertrophy or right bundle branch block, T-wave abnormalities, or normal ECG. The primary outcome was major adverse cardiovascular events (MACE) defined as the composite of cardiac death or myocardial infarction. Among 6,059 subjects, 1912 (32%) had baseline ST/T abnormalities. During a mean follow-up of 2.3 ± 1.9 years, the incidence of MACE was significantly higher among patients with secondary ST/T abnormalities compared to those with normal ECG (HR 2.05; 95% confidence interval [CI], 1.04-4.05; P = 0.039). No significant difference in MACE was observed among patients with primary ST abnormalities (HR 1.64; CI 0.87-3.06; P = 0.124) or T-wave abnormalities (HR 1.15; CI 0.62-2.16; P = 0.658) compared with patients who had normal ECG. Among patients with secondary ST/T changes, abnormal MPI was not associated with a significant increase in MACE rates compared to normal MPI (HR 1.18; CI 0.31-4.58; P = 0.808). However, abnormal MPI was associated with higher MACE rates among patients with primary ST abnormalities (HR 4.50; CI 1.44-14.10; P = 0.005) and T-wave abnormalities (HR 3.74; CI 1.20-11.68; P = 0.015). Similarly, myocardial ischemia on regadenoson stress SPECT-MPI was not associated with a significant increase in MACE rates in patients with secondary ST/T abnormalities (HR 1.45; CI 0.38-5.61; P = 0.588), while it was associated with a higher incidence of MACE in patients with primary ST abnormalities (HR 3.012; CI 0.95-9.53; P = 0.049) and T-wave abnormalities (HR 5.06; CI 1.60-15.96; P = 0.002).

CONCLUSION

While patients with secondary ST/T abnormalities had significantly higher MACE risk, abnormal MPI or presence of myocardial ischemia on regadenoson SPECT-MPI in this group does not add prognostic information. Patients with primary ST abnormalities and T-wave abnormalities do not seem to have a significantly higher MACE risk compared to those with normal ECG; however, abnormal MPI or presence of myocardial ischemia, in these groups, correlates with higher MACE rates.

Nonspecific ST-Segment and T-Wave (NS-STT) on Electrocardiogram is Associated with Increasing the Incidence of Perioperative Deep Vein Thrombosis in Patients with Lower Extremity Fracture Under 75 Years Old

Objective

This study aims to explore the clinical correlation between nonspecific ST-segment or T-wave (NS-STT) changes and perioperative deep vein thrombosis (DVT) in patients with lower extremity fractures.

Methods

One thousand four hundred sixty-nine consecutive patients who suffered lower extremity fractures were screened at Xi’an Honghui Hospital between Feb 2016 and Nov 2018. According to the included and excluded criteria, the patients were included in this retrospective study. After collecting the electrocardiogram baseline, the patients were divided into the NS-STT group and the non-NS-STT group. After comparing the demographic and clinical characteristics, multivariate logistic regression models were used to identify the role of NS-STT changes on perioperative DVT. All analyses were performed with R and EmpowerStats software.

Results

Nine hundred and sixty-eight patients were included in the study. Ninety-seven patients (10.02%) had NS-STT changes on the electrocardiogram at admission. A total of 303 patients (31.30%) developed perioperative DVT in lower extremities. The univariate analysis showed that NS-STT segment changes were correlated with perioperative DVT significantly (OR = 3.45, 95% CI: 2.25–5.30, P < 0.0001). In addition, age ≥50 (P < 0.0001), female (OR = 1.50, 95% CI: 1.14–1.97, P = 0.0038), hypertension (OR = 1.54, 95% CI: 1.08–2.20, P = 0.0161), blood transfusion (OR = 1.78, 95% CI: 1.34–2.37, P < 0.0001), joint prosthesis (OR = 3.26, 95% CI: 2.21–4.81, P < 0.0001), and blood loss ≥300 mL (OR = 2.12, 95% CI: 1.50–3.01, P < 0.0001) were associated with perioperative DVT in lower extremities. We identified the confounding factors of age, gender, classification of internal implants, operation time, blood loss, and infusion. After adjustment for potential confounding factors, NS-STT changes were associated with perioperative DVT (OR = 2.13, 95% CI: 1.33–3.42; P = 0.0017). The sensitive analysis showed that the result was stable.

Conclusion

The NS-STT changes on electrocardiograms are associated with an increase in the incidence of perioperative DVT by 2.13-fold in patients with lower extremity fractures under 75 years old. In clinical practice, surgeons should pay more attention to these patients.

Nonalcoholic fatty liver disease, a potential risk factor of non-specific ST-T segment changes: data from a cross-sectional study

Background

Non-specific ST-T segment changes are prevalent and are proven risk factors for early onset of cardiovascular diseases. They can increase all-cause mortality by 100∼200% and are candidate for early signs of cardiovascular changes. Nonalcoholic fatty liver disease (NAFLD) is prevalent worldwide and is one facet of a multisystem disease that confers substantial increases morbidity and mortality of nonalcoholic fatty liver-related cardiovascular diseases. It is unclear whether NAFLD is associated with non-specific ST-T changes warning early signs of cardiovascular changes. Therefore, we investigated this association.

Methods

A cross-sectional study was designed that included a sample consisting of 32,922 participants who underwent health examinations. Participants with missing information, excessive alcohol intake, viral hepatitis, chronic liver disease or established cardiovascular diseases were excluded. Electrocardiograms were used for analysis of non-specific ST-T segment changes. NAFLD was diagnosed by ultrasonographic detection of hepatic steatosis without other liver diseases. A multivariable logistic regression model was served to calculate the OR and 95% CI for non-specific ST-T segment changes.

Results

The prevalence of non-specific ST-T segment changes was 6.5% in participants with NAFLD, however, the prevalence of NAFLD was 42.9% in participants with non-specific ST-T segment changes. NAFLD was independently associated with non-specific ST-T segment changes (OR: 1.925, 95% CI: 1.727-2.143, P < 0.001). After adjusting for age, sex, heart rate, hypertension, body mass index, fasting glucose, total cholesterol, triglycerides, HDL-C, NAFLD remained an independent risk factor of non-specific ST-T segment changes (OR: 1.289, 95% CI: 1.122-1.480).

Conclusion

Non-specific ST-T segment changes were independently associated with the presence of NAFLD after adjusting for potential confounders.

HIV infection and electrocardiogram abnormalities: baseline assessment from the CHART cohort

OBJECTIVES

To investigate the prevalence of various electrocardiogram (ECG) abnormalities among HIV-positive and HIV-negative individuals.

METHODS

This cross-sectional evaluation included 1412 HIV-positive and 2824 HIV-negative participants aged 18 to 75 years and frequency matched by age and sex, derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China, between February and December 2017.

RESULTS

HIV-positive individuals had higher prevalence of sinus tachycardia (5.6% (79/1412) vs. 1.3% (36/2824), p < 0.001) and ST/T wave abnormalities (14.9% (211/1412) vs. 9.4% (264/1412), p < 0.001) but lower prevalence of sinus bradycardia (4.8% (68/1412) vs. 7.5% (211/2824), p 0.001); such associations remained statistically significant after adjusting for traditional risk factors (respectively, adjusted odds ratio (aOR) 4.68, 95% confidence interval (CI) 3.06-7.17; aOR 1.89, 95% CI 1.54-2.34; aOR 0.60, 95% CI 0.44-0.80). In adjusted models, being in higher carotid intima-media thickness categories was significantly associated with ST/T abnormalities in HIV-positive individuals only (0.78-1.00 mm: aOR 1.46, 95% CI 1.01-2.12; >1.00 mm: aOR 2.18, 95% CI 1.39-3.42), whereas being in higher blood pressure categories was significantly associated with both sinus tachycardia (prehypertension: aOR 5.61, 95% CI 1.76-17.91; hypertension: aOR 12.62, 95% CI 3.60-44.27) and ST/T abnormalities (hypertension: aOR 2.04, 95% CI 1.41-2.95) in HIV-negative individuals only. Longer duration of known HIV infection was the only HIV-specific factor of ST/T abnormalities (aOR 1.61, 95% CI 1.17-2.22), with none for sinus tachycardia.

CONCLUSIONS

HIV infection is independently associated with sinus tachycardia and ST/T abnormalities. Further research is needed to investigate specific mechanisms by which HIV infection leads to ECG abnormalities and to evaluate whether inclusion of ECG parameters improves cardiovascular disease prediction. Integrating ECG screening into routine HIV care is recommended in China.

Impact of the Location of ST-T Abnormalities Accompanying Minor Q-Waves on the Definition of Prior Myocardial Infarction

According to the Fourth Universal Definition of myocardial infarction (MI), the likelihood of a previous MI is increased when ST-T abnormalities exist with minor Q-waves in the same leads. Therefore, we examined whether differences in location of ST-T abnormalities in relation to minor Q-waves as part of the old MI definition impact the prevalence and prognostic significance of MI. This analysis included 7,878 participants with available baseline electrocardiogram (ECG) and follow-up data from the third National Health and Nutrition Examination Survey. Two ECG MI definitions were utilized; both were based on the standards of the Minnesota Code (MC) ECG Classification, and both incorporated major Q-waves but differed in whether major ST-T abnormalities and minor Q waves, as part of the definition, were in the same lead group (Standard MC-MI) or not (Fourth Universal MI). All-cause mortality and cardiovascular disease mortality were ascertained during 14 years (median). We found no difference between baseline prevalence of Standard MC-MI (3.48%; n = 274) and Fourth Universal MI (3.27%; n = 258), p = 0.46. Also, Standard MC-MI and Fourth Universal MI were similarly associated with increased risk of all-cause mortality (hazard ratio [95% confidence interval] 1.64 [1.42 to 1.90] and 1.61 [1.38 to 1.87], respectively; p value for differences in associations = 0.86), and cardiovascular disease mortality (hazard ratio [95% confidence interval] 1.99 [1.61 to 2.48] and 1.94 [1.56 to 2.42], respectively; p value for differences in associations = 0.84). In conclusion, the location of ST-T abnormalities accompanying minor Q-waves does not impact the prevalence or prognostic significance of a prior MI which raise doubts about the clinical impact of considering the location of ST-T in relation to minor Q-waves when defining an old MI.

Electrocardiographic ST-T Abnormities Are Associated With Stroke Risk in the REGARDS Study

Background and Purpose- In previous studies, isolated nonspecific ST-segment and T-wave abnormalities (NSSTTAs), a common finding on ECGs, were associated with greater risk for incident coronary artery disease. Their association with incident stroke remains unclear. Methods- The REGARDS (Reasons for Geographic and Racial Differences in Stroke) study is a population-based, longitudinal study of 30 239 white and black adults enrolled from 2003 to 2007 in the United States. NSSTTAs were defined from baseline ECG using the standards of Minnesota ECG Classification (Minnesota codes 4-3, 4-4, 5-3, or 5-4). Participants with prior stroke, coronary heart disease, and major and minor ECG abnormalities other than NSSTTAs were excluded from analysis. Multivariable Cox proportional hazards regression was used to examine calculate hazard ratios of incident ischemic stroke by presence of baseline NSSTTAs. Results- Among 14 077 participants, 3111 (22.1%) had NSSTTAs at baseline. With a median of 9.6 years follow-up, 106 (3.4%) with NSSTTAs had ischemic stroke compared with 258 (2.4%) without NSSTTAs. The age-adjusted incidence rates (per 1000 person-years) of stroke were 2.93 in those with NSSTTAs and 2.19 in those without them. Adjusting for baseline age, sex, race, geographic location, and education level, isolated NSSTTAs were associated with a 32% higher risk of ischemic stroke (hazard ratio, 1.32 [95% CI, 1.05-1.67]). With additional adjustment for stroke risk factors, the risk of stroke was increased 27% (hazard ratio, 1.27 [95% CI, 1.00-1.62]) and did not differ by age, race, or sex. Conclusions- Presence of NSSTTAs in persons with an otherwise normal ECG was associated with a 27% increased risk of future ischemic stroke.

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.

Relation of Minor Electrocardiographic Abnormalities to Cardiovascular Mortality

Although minor electrocardiographic (ECG) abnormalities are common findings in clinical practice, their prognostic significance remains unclear due to inconsistent reports. We hypothesized that this inconsistency is due to the traditional focus on examining their prognostic significance as a binary variable (i.e., presence vs absence of any abnormality) ignoring the number of abnormalities. We tested this hypothesis in 6,467 participants (mean age 59 years, 53% women) from the Third National Health and Nutrition Examination Survey who were free of baseline cardiovascular disease (CVD) and major ECG abnormalities. ECG abnormalities were defined from digitally recorded and centrally processed standard electrocardiograms using the Minnesota ECG Classification. CVD mortality was ascertained using National Death Index. About 38% of participants (n = 2,438) had at least 1 minor ECG abnormality at baseline. During a median follow-up of 13.9 years, 755 CVD deaths occurred. In a multivariable Cox model, presence of at least 1 minor ECG abnormality was marginally associated with increased risk of CVD mortality (hazard ratio (95% confidence interval):1.15(1.00,1.34), p-value = 0.04)). However, as the number of ECG abnormalities increases, the association with CVD mortality showed a dose-response relation (event rate per 1,000 person-year of 7.3, 10.1, and 16.7 in participants with 0, 1, and ≥2 ECG abnormalities, respectively; p-value for trend <0.01). Also, each additional minor ECG abnormality was associated with a 13% increased risk of CVD mortality (hazard ratio (95% confidence interval): 1.13(1.04, 1.24)). In conclusion, the number, not only the mere presence of minor ECG abnormalities should be taken into account to understand the prognostic significance of these common findings.

Association of isolated minor nonspecific ST-T abnormalities with left ventricular hypertrophy and diastolic dysfunction

The aim of this study was to examine the associations of isolated minor nonspecific ST-T abnormalities (NSSTTA) on 12-lead electrocardiogram (ECG) with left ventricular (LV) diastolic function and LV geometry on echocardiography. A cross-sectional study comprised of 74,976 Koreans who underwent ECG and echocardiography as part of a comprehensive health examination between March 2011 and December 2014. ECG was coded using Minnesota Code criteria. The frequencies of NSSTTA, impaired LV relaxation, and echocardiographic LVH were 1,139 (1.5%), 21,118 (28.2%), and 1,687 (2.3%) patients, respectively. The presence of NSSTTA was positively associated with the prevalence of impaired LV relaxation and LVH on echocardiography. In a multivariable-adjusted model, the odds ratio (95% CIs) comparing patients with NSSTTA to control patients was 1.55 (1.33-1.80) for impaired LV relaxation and 3.15 (2.51-3.96) for echocardiographic LVH. The association between NSSTTA and impaired LV relaxation was stronger in the intermediate to high cardiovascular disease-risk group than in the low-risk group according to Framingham Risk Score stratification (P for interaction = 0.02). NSSTTA were associated with increased prevalence of impaired LV relaxation and LVH, suggesting NSSTTA as an early indicator of subclinical cardiac dysfunction and geometric abnormalities.

Prevalence of electrocardiographic abnormalities in primary care patients according to sex and age group. A retrospective observational study

BACKGROUND

Knowledge of the prevalence of electrocardiographic abnormalities in a population is useful for interpreting the findings. The aim here was to assess the prevalence of electrocardiographic abnormalities and self-reported comorbidities and cardiovascular risk factors according to sex and age group among Brazilian primary care patients.

DESIGN AND SETTING

Observational retrospective study on consecutive primary care patients in 658 cities in the state of Minas Gerais, Brazil, whose digital electrocardiograms (ECGs) were sent for analysis to the team of the Telehealth Network of Minas Gerais (TNMG).

METHODS

All ECGs analyzed by the TNMG team in 2011 were included. Clinical data were self-reported and electrocardiographic abnormalities were stratified according to sex and age group.

RESULTS

A total of 264,324 patients underwent ECG examinations. Comorbidities and cardiovascular risk factors were more frequent among women, except for smoking. Atrial fibrillation and flutter, premature beats, intraventricular blocks, complete right bundle branch block and left ventricular hypertrophy were more frequent among men, and nonspecific ventricular repolarization abnormalities and complete left bundle branch block among women.

CONCLUSION

Electrocardiographic abnormalities were relatively common findings, even in the younger age groups. The prevalence of electrocardiographic abnormalities increased with age and was higher among men in all age groups, although women had higher frequency of self-reported comorbidities.

Nonspecific ST-T changes associated with unsatisfactory blood pressure control among adults with hypertension in China: Evidence from the CSPTT study

Nonspecific ST-segment and T-wave (ST-T) changes represent one of the most prevalent electrocardiographic abnormalities in hypertensive patients. However, a limited number of studies have investigated the association between nonspecific ST-T changes and unsatisfactory blood pressure (BP) control in adults with hypertension.The study population comprised 15,038 hypertensive patients, who were selected from 20,702 participants in the China Stroke Primary Prevention Trial. The subjects were examined with electrocardiogram test at the initial visit in order to monitor baseline heart activity. According to the results of the electrocardiogram (defined by Minnesota coding), the subjects were divided into 2 groups: ST-T abnormal and ST-T normal. Unsatisfactory BP control was defined as systolic BP ≥140 mm Hg or diastolic BP ≥90 mm Hg following antihypertensive treatment during the 4.5-year follow-up period. Multivariate analysis was used to analyze the association between nonspecific ST-T abnormalities and unsatisfactory BP control.Nonspecific ST-T changes were common in hypertensive adults (approximately 8.5% in the study), and more prevalent in women (10.3%) and diabetic patients (13.9%). The unsatisfactory BP control rate was high in the total population (47.0%), notably in the ST-T abnormal group (55.5%). The nonspecific ST-T abnormal group exhibited a significantly greater rate of unsatisfactory BP control (odds ratio [OR] 1.20, 95% confidence interval [CI] [1.06, 1.36], P = 0.005]), independent of traditional risk factors, as demonstrated by multivariate regression analysis. Notable differences were further observed in male subjects (OR 1.51, 95% CI [1.17, 1.94], P = 0.002) and in patients with comorbid diabetes (OR 1.47, 95% CI [1.04, 2.07], P = 0.029).Greater rates of unsatisfactory BP control in hypertensive patients with electrocardiographic nonspecific ST-T abnormalities were observed, notably in the subcategories of the male subjects and the diabetic patients.

Clinical Characteristics and Outcomes of Patients with Myocardial Infarction, Myocardial Injury, and Nonelevated Troponins

BACKGROUND

Cardiac troponins have emerged as the preferred biomarkers for detecting myocardial necrosis and diagnosing myocardial infarction. However, current cardiac troponin assays do not discriminate between ischemic and nonischemic causes of myocardial cell death. Thus, when an increased troponin value is encountered in the absence of obvious myocardial ischemia, a careful search for other clinical conditions is crucial.

METHODS

In 2010 to 2011, we prospectively studied hospitalized patients who had cardiac troponin I measured on clinical indication. An acute myocardial infarction was diagnosed in cases of a cardiac troponin I increase or decrease pattern with at least 1 value >30 ng/L (99th percentile) together with myocardial ischemia. Myocardial injury was defined as cardiac troponin I values >30 ng/L, but without signs or symptoms indicating overt cardiac ischemia. Patients with peak values ≤30 ng/L were classified as nonelevated cardiac troponin I. Follow-up was at least 3 years with all-cause mortality as the sole clinical end point.

RESULTS

A total of 3762 patients were included. Of these, 488 (13%) had acute myocardial infarction, 1089 (29%) had myocardial injury, and 2185 (58%) had nonelevated cardiac troponin I values. Patients with myocardial injury frequently presented with dyspnea, were older, and had more comorbidity than patients in the 2 other groups. During a median follow-up of 3.2 years, 1342 patients died. Mortality differed significantly between groups: 39% in those with myocardial infarction, 59% in those with myocardial injury, and 23% in those with nonelevated cardiac troponin I (log-rank test; P < .0001). No significant difference in mortality between patients with type 2 myocardial infarction and patients with myocardial injury was observed (63% and 59%, respectively).

CONCLUSIONS

Patients with myocardial injury are older and have more comorbidity than those with acute myocardial infarction. Both groups exhibit a poorer prognosis than patients with nonelevated cardiac troponin I values. Of note, a very high long-term mortality is observed in patients with type 2 myocardial infarction and patients with myocardial injury.

Electrocardiographic Predictors of Cardiovascular Mortality

Cardiovascular diseases are the main causes of mortality. Sudden cardiac death may also appear in athletes, due to underlying congenital or inherited cardiac abnormalities. The electrocardiogram is used in clinical practice and clinical trials, as a valid, reliable, accessible, inexpensive method. The aim of the present paper was to review electrocardiographic (ECG) signs associated with cardiovascular mortality and the mechanisms underlying those associations, providing a brief description of the main studies in this area, and consider their implication for clinical practice in the general population and athletes. The main ECG parameters associated with cardiovascular mortality in the present paper are the P wave (duration, interatrial block, and deep terminal negativity of the P wave in V1), prolonged QT and Tpeak-Tend intervals, QRS duration and fragmentation, bundle branch block, ST segment depression and elevation, T waves (inverted, T wave axes), spatial angles between QRS and T vectors, premature ventricular contractions, and ECG hypertrophy criteria.

Ischemic Electrocardiographic Abnormalities and Prognosis in Decompensated Heart Failure

Background—

Identification of coronary ischemia may enable targeted diagnostic and therapeutic strategies for acute heart failure. We determined the risk of 30-day mortality associated with ischemic ECG abnormalities in patients with acute heart failure.

Methods and Results—

Among 8772 patients (53.4% women, median 78 years [Q1, Q3: 68,84]) presenting with acute heart failure to 86 hospital emergency departments in Ontario, Canada, Q-waves, T-wave inversion, or ST-depression were present in 51.8% of subjects. However, presence of ST-depression was the only finding associated with 30-day mortality with adjusted odds ratio 1.24 (95% confidence interval [CI], 1.02–1.50). Using continuous net reclassification improvement, addition of ST-depression to the Emergency Heart failure Mortality Risk Grade model reclassified 16.9% of patients overall, and 29.3% of those with a history of ischemic heart disease (both P <0.001). By adding ST-depression to the model, the Emergency Heart failure Mortality Risk Grade was extended to predict 30-day death with high discrimination ( c -statistic 0.801), with 0.57% mortality rate in the lowest risk decile. Adjusted odds ratios for 30-day mortality were 2.81 (95% CI, 1.48–5.31; P =0.002) in quintile 2, 7.41 (95% CI, 4.13–13.30; P <0.001) in quintile 3, and 14.47 (95% CI, 8.20–25.54; P <0.001) in quintile 4 compared with the lowest risk quintile. When the highest risk quintile was subdivided into 2 equally sized risk strata (deciles 9 and 10), the adjusted odds ratios for 30-day mortality were 27.20 (95% CI, 15.33–48.27; P <0.001) in decile 9 and 58.96 (95% CI, 33.54–103.65; P <0.001) in highest risk decile 10.

Conclusions—

Presence of ST-depression on the ECG reclassified risk of 30-day mortality in patients with acute heart failure, identifying both high- and low-risk subsets.

Electrocardiographic changes improve risk prediction in asymptomatic persons age 65 years or above without cardiovascular disease

BACKGROUND

Risk prediction in elderly patients is increasingly relevant due to longer life expectancy.

OBJECTIVES

This study sought to examine whether electrocardiographic (ECG) changes provide prognostic information incremental to current risk models and to the conventional risk factors.

METHODS

In all, 6,991 participants from the Copenhagen Heart Study attending an examination at age ≥65 years were included. ECG changes were defined as Q waves, ST-segment depression, T-wave changes, ventricular conduction defects, and left ventricular hypertrophy based on the Minnesota code. The primary endpoint was fatal cardiovascular disease (CVD) event and the secondary was fatal or nonfatal CVD event. In our study, 2,236 fatal CVD and 3,849 fatal or nonfatal CVD events occurred during a median of 11.9 and 9.8 years of follow-up.

RESULTS

ECG changes were frequently present (30.6%) and associated with conventional risk factors. All ECG changes except 1 univariably predicted both endpoints. Event rates of ECG changes versus no ECG changes were respectively 41.4% versus 27.8% and 64.6% versus 50.8%. When added to existing risk scores, ECG changes independently increased the risk of both endpoints. Fatal CVD events: hazard ratio (HR): 1.33 (95% confidence interval [CI]: 1.29 to 1.36; p < 0.001) and fatal or nonfatal CVD events: HR: 1.21 (95% CI: 1.19 to 1.24; p < 0.001). When added to conventional risk factors, continuous net reclassification improvement was 42.3% (95% CI: 42.0 to 42.4; p < 0.001) for fatal and 29.2% (95% CI: 28.4 to 29.2; p < 0.001) for fatal or nonfatal events. Categorical net reclassification was 7.1% (95% CI: 6.7 to 9.0; p < 0.001) for fatal and 4.2% (95% CI: 3.5 to 5.6; p < 0.001) for fatal or nonfatal events.

CONCLUSIONS

Simple assessment of the existence of ECG changes improves risk prediction in the general population of persons age ≥65 years.

Electrocardiographic abnormalities and coronary artery calcium for coronary heart disease prediction and reclassification: the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Electrocardiographic (ECG) abnormalities and coronary artery calcium (CAC) identify different aspects of subclinical coronary heart disease (CHD). We sought to determine whether ECG abnormalities improve risk prediction for all CHD and fatal CHD events jointly with CAC measures.

METHODS

We included 6,406 men and women from the MESA aged 45 to 84 years who were free of cardiovascular disease at the time of enrollment (2000-2002). We stratified participants by presence of ST-T and Q wave abnormalities: any major, any minor/no major, and no major/minor using the Minnesota Code classifications. CAC score was defined into one of the following strata: 0, 1 to 100, 101 to 300, greater than 300. We created risk prediction models using MESA-specific coefficients for traditional risk factors (RFs) and calculated categorical net reclassification improvement (NRI) for all and fatal CHD.

RESULTS

Over a median follow-up of 10 years, we observed that the addition of ECG abnormalities to a risk prediction model for all CHD resulted in a categorical NRI of 0.05 (P = .04). For fatal CHD alone, the addition of ECG abnormalities resulted in categorical NRI of 0.09 (P = .02). Addition of ECG abnormalities to a model containing RFs and CAC resulted in categorical NRI of 0.02 (P = .11) for all CHD events. We also observed differences in the association between ECG abnormalities and CHD when stratifying by CAC presence.

CONCLUSION

Electrocardiographic abnormalities improved risk prediction for CHD when added to RFs but not when added to CAC. Electrocardiographic abnormalities particularly improved risk prediction for fatal CHD.

Electrocardiographic repolarization-related variables as predictors of coronary heart disease death in the women's health initiative study

BACKGROUND

We evaluated 25 repolarization-related ECG variables for the risk of coronary heart disease (CHD) death in 52 994 postmenopausal women from the Women's Health Initiative study.

METHODS AND RESULTS

Hazard ratios from Cox regression were computed for subgroups of women with and without cardiovascular disease (CVD). During the average follow-up of 16.9 years, 941 CHD deaths occurred. Based on electrophysiological considerations, 2 sets of ECG variables with low correlations were considered as candidates for independent predictors of CHD death: Set 1, Ѳ(Tp|Tref), the spatial angle between T peak (Tp) and normal T reference (Tref) vectors; Ѳ(Tinit|Tterm), the angle between the initial and terminal T vectors; STJ depression in V6 and rate-adjusted QTp interval (QTpa); and Set 2, TaVR and TV1 amplitudes, heart rate, and QRS duration. Strong independent predictors with over 2-fold increased risk for CHD death in women with and without CVD were Ѳ(Tp|Tref) >42° from Set 1 and TaVR amplitude >-100 μV from Set 2. The risk for these CHD death predictors remained significant after multivariable adjustment for demographic/clinical factors. Other significant predictors for CHD death in fully adjusted risk models were Ѳ(Tinit|Tterm) >30°, TV1 >175 μV, and QRS duration >100 ms.

CONCLUSIONS

Ѳ(Tp|Tref) angle and TaVR amplitude are associated with CHD mortality in postmenopausal women. The use of these measures to identify high-risk women for further diagnostic evaluation or more intense preventive intervention warrants further study.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00000611.

Investigation on cardiovascular risk prediction using physiological parameters

Cardiovascular disease (CVD) is the leading cause of death worldwide. Early prediction of CVD is urgently important for timely prevention and treatment. Incorporation or modification of new risk factors that have an additional independent prognostic value of existing prediction models is widely used for improving the performance of the prediction models. This paper is to investigate the physiological parameters that are used as risk factors for the prediction of cardiovascular events, as well as summarizing the current status on the medical devices for physiological tests and discuss the potential implications for promoting CVD prevention and treatment in the future. The results show that measures extracted from blood pressure, electrocardiogram, arterial stiffness, ankle-brachial blood pressure index (ABI), and blood glucose carry valuable information for the prediction of both long-term and near-term cardiovascular risk. However, the predictive values should be further validated by more comprehensive measures. Meanwhile, advancing unobtrusive technologies and wireless communication technologies allow on-site detection of the physiological information remotely in an out-of-hospital setting in real-time. In addition with computer modeling technologies and information fusion. It may allow for personalized, quantitative, and real-time assessment of sudden CVD events.

Low diastolic blood pressure was one of the independent predictors of ischemia-like findings of electrocardiogram in patients who underwent coronary angiography

BACKGROUND

The underlying cause of a high cardiovascular event rate in the population with low diastolic blood pressure (DBP) has not been fully elucidated.

METHODS AND RESULTS

The relationship between DBP and ischemia-like findings on electrocardiography (ECG) was investigated in 187 patients who underwent coronary angiography. Patients with conditions affecting ECG (e.g. patients taking digitalis or those with old myocardial infarction, complete right bundle branch block, or hypokalemia) were excluded from the analyses. Ischemia-like ECG was defined as having one or more of the following: borderline Q wave [Minnesota code (MC) I 3], ST depression (MC IV 1-3), negative T wave (MC V 1-3), and complete left bundle branch block (MC VII 1). Based on this definition, 70 of 187 patients (37%) had ischemia-like ECG. Compared with the group without it, the group with ischemia-like ECG included more females (p<0.01), and had lower values of body mass index (p = 0.01), DBP (p<0.01), estimated glomerular filtration rate (p<0.01), left ventricular ejection fraction (LVEF; p<0.01), and higher values of age (p<0.01) and left ventricular mass index (LVMI; p<0.01). The severity of coronary artery disease did not differ between the groups. Receiver operating characteristics curve analysis revealed that 74.5 mmHg was the optimal cut-off point of DBP to predict ischemia-like ECG (area under curve, 0.63; 95% confidence interval, 0.55-0.71, p = 0.003). There were no significant relationships between systolic blood pressure and ischemia-like ECG. A multivariate analysis showed that female sex, low DBP (≤ 74.5 mmHg), LVMI, and LVEF were the significant factors for the ischemia-like ECG. The odds ratio of low DBP was 2.53 (95% confidence interval, 1.19-5.40; p = 0.02).

CONCLUSIONS

Low DBP was one of the significant predictors of the ischemia-like ECG in the present study. Myocardial ischemia may be a part of the cause of high cardiovascular morbidity in the population with low DBP.

Minor isolated Q waves and cardiovascular events in the MESA study

BACKGROUND

The significance of minor isolated Q waves in the resting electrocardiograms (ECGs) of apparently healthy individuals is unknown.

OBJECTIVE

To examine the association between minor isolated Q waves and incident cardiovascular disease events in the Multi-Ethnic Study of Atherosclerosis (MESA).

DESIGN

This analysis included 6551 MESA participants (38% white, 28% black, 22% Hispanic, 12% Chinese) who were free of cardiovascular disease at enrollment. Cox proportional hazards models were used to examine the association between minor isolated Q waves defined by the Minnesota ECG Classification with adjudicated incident cardiovascular events.

RESULTS

During up to 7.8 years of follow-up, 423 events occurred, with a rate of 10.7 events per 1000 person-years. A significant interaction between minor isolated Q waves and race/ethnicity was observed (P=.030). In models stratified by race/ethnicity and adjusted for demographics, socioeconomic status, common cardiovascular risk factors, and other ECG abnormalities, presence of isolated minor Q waves was significantly associated with incident cardiovascular events in Hispanics (hazard ratio [HR] 2.62; 95% confidence interval [CI], 1.42-4.82), but not in whites (HR 0.65; 95% CI, 0.32-1.33) or blacks (HR 1.46; 95% CI, 0.74-2.89). Despite the statistically significant association in the Chinese population, the small number of events precluded solid conclusions in this race/ethnicity.

CONCLUSION

The prognostic significance of minor isolated Q waves varies across races/ethnicities; they carry a high risk for future cardiovascular events in apparently healthy Hispanics, but not in whites or blacks.

Basal and ischemia-induced transcardiac troponin release into the coronary circulation in patients with suspected coronary artery disease

Background

Cardiac troponin is a specific biomarker for cardiomyocyte necrosis in acute coronary syndromes. Troponin release from the coronary circulation remains to be determined because of the lower sensitivity of the conventional assay. We sought to determine basal and angina-induced troponin release using a highly sensitive troponin assay.

Methods and Results

The cardiac troponin T levels in serum sampled from the peripheral vein (PV), the aortic root (AO), and the coronary sinus (CS) were measured in 105 consecutive stable patients with coronary risk factor(s) and suspected coronary artery disease (CAD) and in 33 patients without CAD who underwent an acetylcholine provocation test. At baseline, there was a significant increase in the troponin levels from AO [9.0 (6.4, 13.1) pg/mL for median (25^th, 75^th percentiles)] to CS [10.3 (7.3, 15.5) pg/mL, p<0.001] in 96 (91.4%) patients and the difference was 1.1 (0.4, 2.1) pg/mL, which reflected basal transcardiac troponin release (TTR). TTR was positively correlated with PV levels (r = 0.22, p = 0.03). Male sex, left ventricular hypertrophy determined by echocardiography, T-wave inversion, and CAD correlated with elevated TTR defined as above: median, 1.1 pg/mL. A significant increase in TTR was noted in 17 patients with coronary spasms [0.6 (0.2, 1.2) pg/mL, p<0.01] but not in 16 patients without spasms [0.0 (−0.5, 0.9) pg/mL, p = 0.73] after the acetylcholine provocation.

Conclusion

Basal TTR in the coronary circulation was observed in most of the patients with suspected CAD and risk factor(s). This sensitive assay detected myocardial ischemia-induced increases in TTR caused by coronary spasms.

Left ventricular vortex formation is unaffected by diastolic impairment

Normal left ventricular (LV) filling occurs rapidly early in diastole caused by a progressive pressure gradient within the ventricle and with a low left atrial pressure. This normal diastolic function is altered in patients with heart failure. Such impairment of diastolic filling is manifested as an abrupt deceleration of the early filling wave velocity. Although variations within the early filling wave have been observed previously, the underlying hydrodynamic mechanisms are not well understood. Previously, it was proposed that the mitral annulus vortex ring formation time was the total duration of early diastolic filling and provided a measure of the efficiency of diastolic filling. However, we found that the favorable LV pressure difference driving early diastolic filling becomes zero simultaneously with the deceleration of the early filling wave propagation velocity and pinch-off of the LV vortex ring. Thus we calculated the vortex ring formation time using the duration of the early diastolic filling wave from its initiation to the time of the early filling wave propagation velocity deceleration when pinch-off occurs. This formation time does not vary with decreasing intraventricular pressure difference or with degree of diastolic dysfunction. Thus we conclude the vortex ring pinch-off occurs before the completion of early diastole, and its formation time remains invariant to changes of diastolic function.

Association of isolated minor non-specific ST-segment and T-wave abnormalities with subclinical atherosclerosis in a middle-aged, biracial population: Coronary Artery Risk Development in Young Adults (CARDIA) study

AIMS

Isolated minor non-specific ST-segment and T-wave abnormalities (NSSTTAs) are common and known to be independent electrocardiographic risk markers for future cardiovascular disease (CVD) events. The association of NSSTTA with subclinical atherosclerosis is not well defined, but has been postulated as a potential mechanism of association with future clinical events.

METHODS AND RESULTS

We studied participants from the Year 20 examination of the middle-aged, biracial CARDIA cohort. This examination included measurement of traditional risk factors, 12-lead electrocardiograms (ECGs), coronary artery calcium (CAC) measurement and common carotid intima-media thickness (CC-IMT). ECGs were coded using both Minnesota Code (MC) and Novacode (NC) criteria. Isolated minor STTA was defined by MC as presence of MC 4-3, 4-4, 5-3, or 5-4, and by NC as presence of NC 5.8. ECGs with secondary causes of STTA (i.e., LVH) were excluded. Multivariable logistic regression was used to determine the cross-sectional association of isolated minor NSSTTAs with CAC and CC-IMT. The study sample consisted of 2175 participants with an average age of 45 years (57% female and 43% Black). Isolated NSSTTAs were present in 5.1% of males and 6.3% of females. No association was observed between NSSTTA and CAC. After multivariable-adjustment for traditional CVD risk factors, the presence of isolated minor NSSTTAs remained significantly associated with the extent of CC-IMT (odds ratio 1.25 (1.06-1.48), p < 0.01). This association remained significant after further adjustment for CAC.

CONCLUSIONS

Isolated minor NSSTTAs were associated with the extent of CC-IMT, but not with CAC, in this middle-aged biracial cohort. Further study is needed to elucidate potential mechanisms for these findings.

Isolated nonspecific ST-segment and T-wave abnormalities in a cross-sectional United States population and Mortality (from NHANES III)

Most clinicians regard isolated, minor, or nonspecific ST-segment and T-wave (NS-STT) abnormalities to be incidental, often transient, and benign findings in asymptomatic patients. We sought to evaluate whether isolated NS-STT abnormalities on routine electrocardiograms (ECGs) are associated with increased risk of cardiovascular mortality (CM) and all-cause mortality (AM) in a cross-sectional United States population without known coronary artery disease. We included all adults 40 to 90 years of age without known coronary artery disease or risk equivalent based on history and laboratory values, enrolled in the NHANES III from 1988 to 1994, with electrocardiographic data available, and a total follow-up period of 59,781.75 patient-years. NS-STT abnormalities were defined by Minnesota Coding. Subjects were excluded if their mortality data were missing or if they had major electrocardiographic abnormalities, heart rate >120 beats/min, nonsinus rhythm, cardiac infarction/injury score ≥ 20 on ECG, left ventricular hypertrophy by Minnesota Codes 3.1 and 3.3, or patient-reported history coronary artery disease, congestive heart failure, stroke, diabetes, or peripheral arterial disease. The remaining 4,426 subjects were stratified by presence or absence of NS-STT abnormalities. Mortality was judged based on International Classification of Diseases, Tenth Revision coding linked to the National Death Index. Cox proportional hazard ratio was used for multivariate analysis, showing that CM (hazards ratio 1.71, 95% confidence interval 1.04 to 2.83, p = 0.04) and AM (hazards ratio 1.37, 95% confidence interval 1.03 to 1.81, p = 0.02) were significantly higher in the isolated NS-STT abnormalities group. In conclusion, isolated NS-STT abnormalities on ECG were associated with a higher incidence of CM and AM in this large nationally representative cross-sectional cohort without known coronary artery disease or coronary artery disease risk equivalents.

Frequency and relevance of ischemic electrocardiographic findings in patients with chronic obstructive pulmonary disease

Cardiovascular disease is common in patients with chronic obstructive pulmonary disease (COPD) but often remains unrecognized. Ischemic electrocardiographic (ECG) changes are associated with a higher risk of dying from coronary heart disease but have never been systematically evaluated in COPD. Also, their relation to clinical outcome has not been studied. We aimed to determine the frequency of ischemic ECG changes and its relevance in relation to clinical outcome and predictors of impaired survival in patients with COPD. Clinical characteristics, pulmonary function, and co-morbidities were assessed in 536 patients with COPD during baseline assessment of a comprehensive pulmonary rehabilitation program. Moreover, electrocardiograms at rest were obtained in all patients. All electrocardiograms were scored independently by 2 cardiologists using the Minnesota scoring system. Major or minor Q or QS pattern, ST junction and segment depression, T-wave items, or left bundle branch block were considered ischemic ECG changes. One hundred thirteen patients (21%) had ischemic ECG changes. Moreover, 42 of 293 patients (14%) without self-reported cardiovascular co-morbidities had ischemic ECG changes. In addition, patients with ischemic ECG changes had higher dyspnea grades (Modified Medical Research Council (mMRC) 2.9 ± 1.1 vs 2.6 ± 1.1, p = 0.032), worse exercise performance (6-minute walking distance 387 ± 126 vs 425 ± 126 m, p = 0.004), more systemic inflammation (high-sensitivity C-reactive protein 11.2 ± 16.2 vs 7.9 ± 10.7 mmol/l, p = 0.01), higher scores on the Charlson Co-morbidity Index (1.8 ± 0.9 vs 1.5 ± 0.8 points), and higher scores BODE (5.3 ± 3.7 vs 4.5 ± 3.4 points, p = 0.033) and on ADO indexes (5.2 ± 1.7 vs 4.8 ± 1.7 points, p = 0.029) compared to patients without ischemic ECG changes, whereas forced expiratory volume in the first second was similar (40.8 ± 15.2% vs 42.6% ± 15.9%, p = 0.30). In conclusion, ischemic ECG changes are common in patients with COPD and associated with poor clinical outcome irrespective of forced expiratory volume in the first second. These results suggest an important role for cardiovascular disease in impaired survival in these patients.

Prognostic significance of serial Q/ST-T changes by the Minnesota Code and Novacode in the Atherosclerosis Risk in Communities (ARIC) study

AIMS

To compare the value of serial electrocardiographic (ECG) changes by the two most widely used ECG classification systems-the Minnesota Code (MC) and Novacode (Nova) for the prediction of subsequent coronary heart disease (CHD) and total mortality.

METHODS AND RESULTS

We studied 12-lead ECGs from 12,477 participants (average age 54 years at baseline; 58% women; 76% non-Hispanic white) in the Atherosclerosis Risk in Communities (ARIC) Study, who were free of CHD at baseline in 1987, had both good-quality ECGs at baseline and at first study-scheduled follow-up visit, and had ECG QRS duration <120 ms. A total 2119 participants died (17%), including 280 CHD deaths during an average 17-year follow up. Cox regression models assessed outcome associated with significant serial ECG changes by MC and Nova separately. For CHD death the hazard ratio was 6.8 (95% CI 3.5-13.3) for incident Nova myocardial infarction (MI), and 5.7 (95% CI 2.7-11.9) for MC-MI in a multivariable model adjusted for clinical and demographic characteristics, and ECG left ventricular hypertrophy. The increased risk for total mortality doubled for both Nova and MC serial ECG MI. Major evolving ST-T wave abnormalities alone were associated with a ≥132% increased risk for CHD death and a 50% increased risk for total mortality by either Nova or MC.

CONCLUSION

ECG serial change by both MC and Nova are equally valuable predictors for future fatal cardiac events and total mortality and hence equally useful prognostic indicators in clinical trials and epidemiological studies.

Electrocardiographic and clinical predictors separating atherosclerotic sudden cardiac death from incident coronary heart disease

OBJECTIVE

To identify specific ECG and clinical predictors that separate atherosclerotic sudden cardiac death (SCD) from incident coronary heart disease (CHD) (non-fatal events and non-sudden death) in the combined cohorts of the Atherosclerosis Risk in Communities study and the Cardiovascular Health Study.

METHODS

This analysis included 18,497 participants (58% females, 24% black individuals, mean age 58 years) who were initially free of clinical CHD. A competing risk analysis was conducted to examine the prognostic significance of baseline clinical characteristics and an extensive electronic database of ECG measurements for prediction of 229 cases of SCD as a first event versus 2297 incident CHD cases (2122 non-fatal events and 175 non-sudden death) that occurred during a median follow-up time of 13 years in the Cardiovascular Health Study and 14 years in the Atherosclerosis Risk in Communities study.

RESULTS

After adjusting for common CHD risk factors, a number of clinical characteristics and ECG measurements were independently predictive of SCD and CHD. However, the risk of SCD versus incident CHD was significantly different for race/ethnicity, hypertension, body mass index (BMI), heart rate, QTc, abnormally inverted T wave in any ECG lead group and level of ST elevation in V2. Black race/ethnicity (compared to non-black) was predictive of high SCD risk but less risk of incident CHD (p value for differences in the risk (HR) for SCD versus CHD <0.0001). Hypertension, increased heart rate, prolongation of QTc and abnormally inverted T wave were stronger predictors of high SCD risk compared to CHD (p value=0.0460, 0.0398, 0.0158 and 0.0265, respectively). BMI was not predictive of incident CHD but was predictive of high SCD risk in a quadratic fashion (p value=0.0220). On the other hand, elevated ST height as measured at the J point and that measured at 60 ms after the J point in V2 were not predictive of SCD but were predictive of high incident CHD risk (p value=0.0251 and 0.0155, respectively).

CONCLUSIONS

SCD and CHD have many risk factors in common. Hypertension, race/ethnicity, BMI, heart rate, QTc, abnormally inverted T wave in any ECG lead group and level of ST elevation in V2 have the potential to separate between the risks of SCD and CHD. These results need to be validated in another cohort.

The risk of Parkinson disease associated with urate in a community-based cohort of older adults

BACKGROUND/AIMS

Studies suggest an inverse association between urate concentration and the risk of Parkinson disease (PD). We investigated this in the Cardiovascular Health Study in an elderly community-based cohort of adults.

METHODS

The association of baseline urate (µmol/l) and incident PD over 14 years was assessed with locally weighted scatterplot smoothing (LOESS) regression from which categories of low (<300 µmol/l), middle (300-500 µmol/l), and high (>500 µmol/l) urate ranges were derived. Multivariate logistic regression models assessed the risk of PD for each urate range. Linear and quadratic terms were tested when modeling the association between urate and the risk of PD.

RESULTS

Women had significantly lower urate concentrations than did men [316.8 µmol/l (SD 88.0) vs. 367.4 µmol/l (SD 87.7), p < 0.0001] and in women no associations between urate and PD risk were observed. In men, LOESS curves suggested a U-shaped or threshold effect between urate and PD risk. With the middle range as reference, the risk of developing PD was significantly increased for urate <300 µmol/l (OR 1.69, 95% CI 1.03-2.78) but not for urate >500 µmol/l (OR 1.55, 95% CI 0.72-3.32) in men. A negative linear term was significant for urate <500 µmol/l, and across the entire range a convex quadratic term was significant.

CONCLUSIONS

Results suggest a more complex relationship than previously reported between urate levels and the risk of PD in men. Low urate concentrations were associated with a higher PD risk and high urate concentrations were not associated with a further decrease in PD risk.

Prognostic value of ST-T abnormalities and left high R waves with cardiovascular mortality in Japanese (24-year follow-up of NIPPON DATA80)

Little is known about the prognostic value of ST-segment depression and/or T wave (ST-T abnormalities) with or without left high R waves on electrocardiogram recorded at rest for death from cardiovascular disease (CVD) in Asian populations. Japanese participants without a history of CVD and free of major electrocardiographic (ECG) abnormalities were followed for 24 years. Subjects were divided into 4 groups based on baseline ECG findings: isolated left high R waves, isolated ST-T abnormalities, ST-T abnormalities with left high R waves, and normal electrocardiogram. Cox proportional hazard model was used to estimate risk of CVD mortality in groups with ECG abnormalities compared to the normal group. Of 8,572 participants (44.4% men, mean age 49.5 years; 55.6% women, mean age 49.4 years), 1,142 had isolated left high R waves, 292 had isolated ST-T abnormalities, and 128 had ST-T abnormalities with left high R waves at baseline. Multivariable-adjusted hazard ratios of ST-T abnormalities with left high R waves for CVD mortality were 1.95 (95% confidence interval 1.25 to 3.04) in men and 2.68 (95% confidence interval 1.81 to 3.97) in women. Isolated ST-T abnormalities increased the risk for CVD death by 1.66 times (95% confidence interval 1.01 to 2.71) in men and 1.62 times (95% confidence interval 1.18 to 2.24) in women. Association of ECG abnormalities with CVD mortality was independent of age, body mass index, systolic blood pressure, serum cholesterol, blood glucose, smoking and drinking, and antihypertensive medication. In conclusion, ST-T abnormalities with or without left high R waves on electrocardiogram recorded at rest constitute an independent predictor of CVD mortality in Japanese men and women.

The ECG vertigo in diabetes and cardiac autonomic neuropathy

The importance of diabetes in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes, and its prevalence is steadily increasing. The decrease in cardiac mortality in people with diabetes is lagging behind that of the general population. Cardiovascular disease is a broad term which includes any condition causing pathological changes in blood vessels, cardiac muscle or valves, and cardiac rhythm. The ECG offers a quick, noninvasive clinical and research screen for the early detection of cardiovascular disease in diabetes. In this paper, the clinical and research value of the ECG is readdressed in diabetes and in the presence of cardiac autonomic neuropathy.

Gender differences between the Minnesota code and Novacode electrocardiographic prognostication of coronary heart disease in the cardiovascular health study

The Minnesota Code (MC) and Novacode (Nova) are the most widely used electrocardiographic (ECG) classification systems. The comparative strengths of their classifications for Q- and ST-T-wave abnormalities in predicting coronary heart disease (CHD) events and total mortality have not been evaluated separately by gender. We studied standard 12-lead electrocardiograms at rest from 4,988 participants in the Cardiovascular Health Study. Average age at baseline was 73 years, 60% of participants were women 85% were white, and 22% had a history of cardiovascular disease or presence of ECG myocardial infarction by MC or Nova. Starting in 1989 with an average 17-year follow-up, 65% of participants died and 33% had incident CHD in a cohort free of cardiovascular disease at baseline. Of these, electrocardiograms with major Q-wave or major ST-T abnormalities by MC or Nova predicted increased risk for CHD events and total mortality with no significant differences in predictability between men and women. The study also found that women had fewer major Q-wave changes but more major ST-T abnormalities than men. However, there were no gender differences in predicting CHD events and total mortality. In conclusion, ECG classification systems for myocardial infarction/ischemia abnormalities by MC or Nova are valuable and useful for men and women in clinical trials and epidemiologic studies.

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

AIMS

We determined the gender-specific prognostic importance of quantitative measures of the ST segment and T wave in a community cohort.

METHODS

Data were collected from 5613 Finnish individuals. Four electrocardiogram (ECG) lead groups were used: anterior, lateral, inferior, and lead V5. ST-segment depression, determined at four points along the ST segment, and T-wave amplitude were treated as continuous variables in Cox regression analyses.

RESULTS

During a median follow-up period of 72.4 months, 120 cardiovascular deaths were registered. Among women, lateral lead group as well as lead V5 showed highly significant adjusted hazard ratios at all four ST-depression assessment points. This significance was lost in women ≥ 55 years when those with ECG-based criteria of left ventricular hypertrophy (LVH) were excluded. Results for ST-segment depression were not significant among men. As those with LVH were excluded, men ≥ 55 years showed borderline significance. T-wave amplitude did not reach significance among men, while lateral leads and lead V5 bore prognostic information among women.

CONCLUSION

Quantitative ST-segment depression, regardless of the measurement point, allows prediction of cardiovascular death in women within a general population. However, the effect disappears as those with LVH are excluded. This observation highlights the need for consideration of LVH when depressed ST segments are clinically observed.

Evaluation and comparison of the Minnesota Code and Novacode for electrocardiographic Q-ST wave abnormalities for the independent prediction of incident coronary heart disease and total mortality (from the Women's Health Initiative)

Electrocardiographic (ECG) Q- and ST-T-wave abnormalities predict coronary heart disease (CHD) and total mortality. No comparison has been made of the classification of these abnormalities by the 2 most widely used ECG coding systems for epidemiologic studies-the Minnesota Code (MC) and Novacode (NC). We evaluated 12-lead electrocardiograms from 64,597 participants (49 to 79 years old, 82% non-Hispanic white) in the Women's Health Initiative clinical trial in 1993 to 1998, with a maximum of 11 years of follow-up. We used MC and NC criteria to identify Q-wave, ST-segment, and T-wave abnormalities for comparison. In total, 3,322 participants (5.1%) died during an average 8-year follow-up, and 1,314 had incident CHD in the baseline cardiovascular disease-free group. Independently, ECG myocardial infarction criteria by the MC or NC were generally equivalent and were strong predictors for CHD death and total mortality (hazard ratio 1.62, 95% confidence interval 1.05 to 2.51 for CHD death; hazard ratio 1.36, 95% confidence interval 1.09 to 1.71 for total mortality) in a multivariable analytic model. Electrocardiograms with major ST-T abnormalities by the MC or NC coding system were stronger in predicting CHD deaths and total mortality than was the presence of Q waves alone. In conclusion, the ECG classification systems for myocardial infarction/ischemia abnormalities from the MC and NC are valuable and useful in clinical trials and epidemiologic studies. ST-T abnormalities are stronger predictors for CHD events and total mortality than isolated Q-wave abnormalities.

Association of electrocardiographic abnormalities with coronary artery calcium and carotid artery intima-media thickness in individuals without clinical coronary heart disease (from the Multi-Ethnic Study of Atherosclerosis [MESA])

Isolated minor nonspecific ST-segment and T-wave abnormalities (NSSTAs), minor and major electrocardiographic (ECG) abnormalities are established, independent risk markers for incident cardiovascular events. Their association with subclinical atherosclerosis has been postulated but is not clearly defined. The aim of this study was to define the association between ECG abnormalities and measurements of subclinical atherosclerosis. We studied participants from MESA, a multiethnic sample of men and women 45 to 84 years of age and free of clinical cardiovascular disease at enrollment. Baseline examination included measurement of traditional risk factors, 12-lead electrocardiograms at rest, coronary artery calcium (CAC) measurement, and common carotid intima-media thickness (CC-IMT). Electrocardiograms were coded using Novacode criteria and were defined as having minor abnormalities (e.g., minor NSSTTAs, first-degree atrioventricular block, and QRS-axis deviations) or major abnormalities (e.g., pathologic Q waves, major STTAs, significant dysrhythmias, and conduction system delays). Multivariable logistic and linear regressions were used to determine cross-sectional associations of ECG abnormalities with CAC and CC-IMT. Of 6,710 participants, 52.7% were women, with a mean age of 62 years. After multivariable adjustment, isolated minor STTAs and minor and major ECG abnormalities were not associated with presence of CAC (>0) in men (odds ratio 1.04, 95% confidence interval 0.81 to 1.33; 1.10, 0.91 to 1.32; and 1.03, 0.81 to 1.31, respectively) or women (1.01, 0.82 to 1.24; 1.04, 0.87 to 1.23; and 0.94, 0.73 to 1.22, respectively). Lack of association remained consistent when using log CAC and CC-IMT as continuous variables. In conclusion, ECG abnormalities are not associated with markers of subclinical atherosclerosis in a large multiethnic cohort.