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)

Sex-Associated Metabolites and Incident Stroke, Incident Coronary Heart Disease, Hypertension, and Chronic Kidney Disease in the REGARDS Cohort

BACKGROUND

Sex disparities exist in cardiometabolic diseases. Metabolomic profiling offers insight into disease mechanisms, as the metabolome is influenced by environmental and genetic factors. We identified metabolites associated with sex and determined if sex-associated metabolites are associated with incident stoke, incident coronary heart disease, prevalent hypertension, and prevalent chronic kidney disease.

METHODS AND RESULTS

Targeted metabolomics was conducted for 357 metabolites in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) case-cohort substudy for incident stroke. Weighted logistic regression models were used to identify metabolites associated with sex in REGARDS. Sex-associated metabolites were replicated in the HyperGEN (Hypertension Genetic Epidemiology Network) and using the literature. Weighted Cox proportional hazard models were used to evaluate associations between metabolites and incident stroke. Cox proportional hazard models were used to evaluate associations between metabolites and incident coronary heart disease. Weighted logistic regression models were used to evaluate associations between metabolites and hypertension and chronic kidney disease. Fifty-one replicated metabolites were associated with sex. Higher levels of 6 phosphatidylethanolamines were associated with incident stroke. No metabolites were associated with incident coronary heart disease. Higher levels of uric acid and leucine and lower levels of a lysophosphatidylcholine were associated with hypertension. Higher levels of indole-3-lactic acid, 7 phosphatidylethanolamines, and uric acid, and lower levels of betaine and bilirubin were associated with chronic kidney disease.

CONCLUSIONS

These findings suggest that the sexual dimorphism of the metabolome may contribute to sex differences in stroke, hypertension, and chronic kidney disease.

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.

Electrocardiographic Predictors of Mortality: Data from a Primary Care Tele-Electrocardiography Cohort of Brazilian Patients

Computerized electrocardiography (ECG) has been widely used and allows linkage to electronic medical records. The present study describes the development and clinical applications of an electronic cohort derived from a digital ECG database obtained by the Telehealth Network of Minas Gerais, Brazil, for the period 2010–2017, linked to the mortality data from the national information system, the Clinical Outcomes in Digital Electrocardiography (CODE) dataset. From 2,470,424 ECGs, 1,773,689 patients were identified. A total of 1,666,778 (94%) underwent a valid ECG recording for the period 2010 to 2017, with 1,558,421 patients over 16 years old; 40.2% were men, with a mean age of 51.7 [SD 17.6] years. During a mean follow-up of 3.7 years, the mortality rate was 3.3%. ECG abnormalities assessed were: atrial fibrillation (AF), right bundle branch block (RBBB), left bundle branch block (LBBB), atrioventricular block (AVB), and ventricular pre-excitation. Most ECG abnormalities (AF: Hazard ratio [HR] 2.10; 95% CI 2.03–2.17; RBBB: HR 1.32; 95%CI 1.27–1.36; LBBB: HR 1.69; 95% CI 1.62–1.76; first degree AVB: Relative survival [RS]: 0.76; 95% CI0.71–0.81; 2:1 AVB: RS 0.21 95% CI0.09–0.52; and RS 0.36; third degree AVB: 95% CI 0.26–0.49) were predictors of overall mortality, except for ventricular pre-excitation (HR 1.41; 95% CI 0.56–3.57) and Mobitz I AVB (RS 0.65; 95% CI 0.34–1.24). In conclusion, a large ECG database established by a telehealth network can be a useful tool for facilitating new advances in the fields of digital electrocardiography, clinical cardiology and cardiovascular epidemiology.

Ascertainment of Silent Myocardial Infarction in Patients Undergoing Percutaneous Coronary Intervention (from the GLOBAL LEADERS Trial)

Q-wave myocardial infarction (QWMI) comprises 2 entities. First, a clinically evident MI, which can occur spontaneously or be related to a coronary procedure. Second, silent MI which is incidentally detected on serial electrocardiographic (ECG) assessment. The prevalence of silent MI after percutaneous coronary intervention (PCI) in the drug-eluting stent era has not been fully investigated. The GLOBAL LEADERS is an all-comers multicenter trial which randomized 15,991 patients who underwent PCI to 2 antiplatelet treatment strategies. The primary end point was a composite of all-cause death or nonfatal new QWMI at 2-years follow-up. ECGs were collected at discharge, 3-month and 2-year visits, and analyzed by an independent ECG core laboratory following the Minnesota code. All new QWMI were further reviewed by a blinded independent cardiologist to identify a potential clinical correlate by reviewing clinical information. Of 15,968 participants, ECG information was complete in 14,829 (92.9%) at 2 years. A new QWMI was confirmed in 186 (1.16%) patients. Transient new Q-waves were observed in 28.5% (53 of 186) of them during the follow-up. The majority of new QWMI (78%, 146 of 186) were classified as silent MI due to the absence of a clinical correlate. Silent MI accounted for 22.1% (146 of 660) of all MI events. The prevalence of silent MI did not differ significantly between treatment strategies (experimental vs reference: 0.88% vs 0.98%, p = 0.5027). In conclusion, we document the prevalence of silent MI in an all-comers population undergoing PCI in this large-scale randomized trial.

ECG analysis in patients with acute coronary syndrome undergoing invasive management: rationale and design of the electrocardiography sub-study of the MATRIX trial

BACKGROUND

The twelve‑lead electrocardiogram (ECG) has become an essential tool for the diagnosis, risk stratification, and management of patients with acute coronary syndromes (ACS). However, several areas of residual controversies or gaps in evidence exist. Among them, P-wave abnormalities identifying atrial ischemia/infarction are largely neglected in clinical practice, and their diagnostic and prognostic implications remain elusive; the value of ECG to identify the culprit lesion has been investigated, but validated criteria indicating the presence of coronary occlusion in patients without ST-elevation are lacking; finally, which criteria among the multiple proposed, better define pathological Q-waves or success of revascularisation deserve further investigations.

METHODS

The Minimizing Adverse hemorrhagic events via TRansradial access site and systemic Implementation of AngioX (MATRIX) trial was designed to test the impact of bleeding avoidance strategies on ischemic and bleeding outcomes across the whole spectrum of patients with ACS receiving invasive management. The ECG-MATRIX is a pre-specified sub-study of the MATRIX programme which aims at analyzing the clinical value of ECG metrics in 4516 ACS patients (with and without ST-segment elevation in 2212 and 2304 cases, respectively) with matched pre and post-treatment ECGs.

CONCLUSIONS

This study represents a unique opportunity to further investigate the role of ECGs in the diagnosis and risk stratification of ACS patients with or without ST-segment deviation, as well as to assess whether the radial approach and bivalirudin may affect post-treatment ECG metrics and patterns in a large contemporary ACS population.

Trends in electrocardiographic abnormalities and risk of cardiovascular mortality in Lithuania, 1986-2015

Background

This study aimed to assess the trends in the prevalence of electrocardiographic (ECG) abnormalities from 1986 to 2015 and impact of ECG abnormalities on risk of death from cardiovascular diseases (CVD) in the Lithuanian population aged 40–64 years.

Methods

Data from four surveys carried out in Kaunas city and five randomly selected municipalities of Lithuania were analysed. A resting ECG was recorded and CVD risk factors were measured in each survey. ECG abnormalities were evaluated using Minnesota Code (MC). Trends in age-standardized prevalence of ECG abnormalities were estimated for both sexes. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HR) for coronary heart disease (CHD) and CVD mortality. Net reclassification index (NRI), integrated discrimination improvement and other indices were used for evaluation of improvement in the prediction of CVD and CHD mortality risk after addition of ECG abnormalities variable to Cox models.

Results

From1986 to 2008, the decrease in the prevalence of Q-QS MC was observed in both genders. The prevalence of high R waves increased in men, while the prevalence of ST segment and T wave abnormalities as well as arrhythmias decreased in women. Ischemic changes and possible MI were associated with a 2.5-fold and 4.4-fold higher risk of death from CVD in men and 1.51-fold and 2.56-fold higher mortality risk from CVD in women as compared to individuals with marginal or no ECG abnormalities. The addition of ECG abnormalities to traditional CVD risk factors improved Cox regression models performance. According to NRI, 18.6% of men were correctly reclassified in CVD mortality prediction model and 25.2% of men - in CHD mortality prediction model.

Conclusions

the decreasing trends in the prevalence of ischemia on ECG in women and increasing trends in the prevalence of left VH in men were observed. ECG abnormalities were associated with higher risk of CVD mortality. The addition of ECG abnormalities to the prediction models modestly improved the prediction of CVD mortality beyond traditional CVD risk factors. The use of ECG as routine screening to identify high risk individuals for more intensive preventive interventions warrants further research.

Using health-related quality of life to predict cardiovascular disease events

PURPOSE

Although strong associations between self-reported health and mortality exist, quality of life is not conceptualized as a cardiovascular disease (CVD) risk factor. Our objective was to assess the independent association between health-related quality of life (HRQOL) and incident CVD.

METHODS

This study used the REasons for Geographic And Racial Differences in Stroke data, which enrolled 30,239 adults from 2003 to 2007 and followed them over 10 years. We included 22,229 adults with no CVD history at baseline. HRQOL was measured using the SF-12 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores, which range from 0 to 100, with higher scores indicating better HRQOL. Scores were normed to the general US population with mean 50 and standard deviation 10. We constructed a four-level HRQOL variable: (1) individuals with PCS & MCS < 50, (2) PCS < 50 & MCS ≥ 50, (3) MCS < 50 & PCS ≥ 50, and (4) PCS & MCS ≥ 50, which was the reference. The primary outcome was incident CVD (non-fatal myocardial infarction (MI), fatal MI or coronary heart disease (CHD) death, fatal and non-fatal stroke). Cox proportional hazards models examined associations between HRQOL and CVD.

RESULTS

Median follow-up was 8.4 (IQR 5.9-10.0) years. We observed 1766 CVD events. Compared to having PCS & MCS ≥ 50, having MCS & PCS < 50 was associated with increased CVD risk (aHR 1.46; 95% 1.24-1.70), adjusting for demographics, comorbidities, and CVD risk factors. Associations between MCS & PCS < 50 and CVD were consistent for CHD (aHR 1.54 [1.26-1.89]) and stroke (aHR 1.35 [1.05-1.72]) endpoints.

CONCLUSIONS

Given strong, adjusted associations between poor HRQOL and incident CVD, self-reported health may be an excellent complement to current approaches to CVD risk identification.

N-terminal pro-B-type natriuretic peptide and microsize myocardial infarction risk in the reasons for geographic and racial differences in stroke study

Background

N-terminal pro B-type peptide (NT-proBNP) has been associated with risk of myocardial infarction (MI), but less is known about the relationship between NT-proBNP and very small non ST-elevation MI, also known as microsize MI. These events are now routinely detectable with modern troponin assays and are emerging as a large proportion of all MI. Here, we sought to compare the association of NT-proBNP with risk of incident typical MI and microsize MI in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study.

Methods

The REGARDS Study is a national cohort of 30,239 US community-dwelling black and white adults aged ≥ 45 years recruited from 2003 to 2007. Expert-adjudicated outcomes included incident typical MI (definite/probable MI with peak troponin ≥ 0.5 μg/L), incident microsize MI (definite/probable MI with peak troponin < 0.5 μg/L), and incident fatal CHD. Using a case-cohort design, we estimated the hazard ratio of the outcomes as a function of baseline NT-proBNP. Competing risk analyses tested whether the associations of NT-proBNP differed between the risk of incident microsize MI and incident typical MI as well as if the association of NT-proBNP differed between incident non-fatal microsize MI and incident non-fatal typical MI, while accounting for incident fatal coronary heart disease (CHD) as well as heart failure (HF).

Results

Over a median of 5 years of follow-up, there were 315 typical MI, 139 microsize MI, and 195 incident fatal CHD. NT-proBNP was independently and strongly associated with all CHD endpoints, with significantly greater risk observed for incident microsize MI, even after removing individuals with suspected HF prior to or coincident with their incident CHD event.

Conclusion

NT-proBNP is associated with all MIs, but is a more powerful risk factor for microsize than typical MI.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0806-4) contains supplementary material, which is available to authorized users.

Troponin I and T in relation to cardiac injury detected with electrocardiography in a population-based cohort - The Maastricht Study

Interest in high-sensitivity cardiac troponin I(hs-cTnI) and T(hs-cTnT) has expanded from acute cardiac care to cardiovascular disease(CVD) risk stratification. Whether hs-cTnI and hs-cTnT are interchangeable in the ambulant setting is largely unexplored. Cardiac injury is a mechanism that may underlie the associations between troponin levels and mortality in the general population. In the population-based Maastricht Study, we assessed the correlation and concordance between hs-cTnI and hs-cTnT. Multiple regression analyses were conducted to assess the association of hs-cTnI and hs-cTnT with electrocardiographic (ECG) changes indicative of cardiac abnormalities. In 3016 eligible individuals(mean age,60 ± 8years;50.6%,men) we found a modest correlation between hs-cTnI and hs-cTnT(r = 0.585). After multiple adjustment, the association with ECG changes indicative of cardiac abnormalities was similar for both hs-cTn assays(OR,hs-cTnI:1.72,95%CI:1.40-2.10;OR,hs-cTnT:1.60,95%CI:1.22–2.11). The concordance of dichotomized hs-cTnI and hs-cTnT was κ = 0.397(≥sex-specific 75^th percentile). Isolated high levels of hs-cTnI were associated with ECG changes indicative of cardiac abnormalities(OR:1.93,95%CI:1.01–3.68), whereas isolated high levels of hs-cTnT were not(OR:1.07,95%CI:0.49–2.31). In conclusion, there is a moderate correlation and limited concordance between hs-cTnI and hs-cTnT under non-acute conditions. These data suggest that associations of hs-cTnI and hs-cTnT with cardiac injury detected by ECG are driven by different mechanisms. This information may benefit future development of CVD risk stratification algorithms.

Pregnancy in advanced age and the risk of stroke in postmenopausal women: analysis of Women's Health Initiative Study

BACKGROUND

The incidence of pregnancy in advanced age among women is increasing because of the availability of assisted reproduction, although the long-term health consequences are not known.

OBJECTIVE

The purpose of this study was to determine the effect of pregnancy in advanced age on the occurrence of cardiovascular events in a large cohort of postmenopausal women.

STUDY DESIGN

We analyzed the data for 72,221 women aged 50-79 years who were enrolled in the observational arm of the Women's Health Initiative study. We determined the effect of pregnancy in advanced age (last pregnancy at age ≥40 year) on the risk of ischemic stroke, hemorrhagic stroke, myocardial infarction, and cardiovascular death over a mean period (±standard deviation) of 12±1 years using Cox Proportional Hazards analysis after adjusting for potential confounders.

RESULTS

A total of 3306 of the 72,221 participants (4.6%) reported pregnancy in advanced age. Compared with pregnancy in normal age, the rates of ischemic stroke (3.8% vs 2.4%), hemorrhagic stroke (1.0% vs 0.5%), and cardiovascular death (3.9% vs 2.3%) were significantly higher among women with pregnancy in advanced age. In multivariate analysis, women with pregnancy in advanced age were 50% more likely to experience a hemorrhagic stroke (hazard ratio, 1.5; 95% confidence interval, 1.0-2.1) after adjustment for age, race/ethnicity, congestive heart failure, systolic blood pressure, atrial fibrillation, alcohol use, and cigarette smoking. There was no significant difference in the risk of ischemic stroke, myocardial infarction, and cardiovascular death among women with pregnancy in advanced age after adjustment for potential confounders.

CONCLUSION

Women with pregnancy at an advanced age have a higher risk for hemorrhagic stroke in the postmenopausal period.

Normal computerized Q wave measurements in healthy young athletes

BACKGROUND

Recent Expert consensus statements have sought to decrease false positive rates of electrocardiographic abnormalities requiring further evaluation when screening young athletes. These statements are largely based on traditional ECG patterns and have not considered computerized measurements.

OBJECTIVE

To define the normal limits for Q wave measurements from the digitally recorded ECGs of healthy young athletes.

METHODS

All athletes were categorized by sex and level of participation (high school, college, and professional), and underwent screening ECGs with routine pre-participation physicals, which were electronically captured and analyzed. Q wave amplitude, area and duration were recorded for athletes with Q wave amplitudes greater than 0.5mm at standard paper amplitude display (1mV/10mm). ANOVA analyses were performed to determine differences these parameters among all groups. A positive ECG was defined by our Stanford Computerized Criteria as exceeding the 99th percentile for Q wave area in 2 or more leads. Proportions testing was used to compare the Seattle Conference Q wave criteria with our data-driven criteria.

RESULTS

2073 athletes in total were screened. Significant differences in Q wave amplitude, duration and area were identified both by sex and level of participation. When applying our Stanford Computerized Criteria and the Seattle criteria to our cohort, two largely different groups of athletes are identified as having abnormal Q waves.

CONCLUSION

Computer analysis of athletes' ECGs should be included in future studies that have greater numbers, more diversity and adequate end points.

Elucidating the Association Between Depressive Symptoms, Coronary Heart Disease, and Stroke in Black and White Adults: The REasons for Geographic And Racial Differences in Stroke (REGARDS) Study

Background

Depression is a relapsing and remitting disease. Prior studies on the association between depressive symptoms and incident cardiovascular disease (CVD) have been limited by single measurements, and few if any have examined both incident coronary heart disease and stroke in a large biracial national cohort. We aimed to assess whether time‐dependent depressive symptoms conferred increased risk of incident CVD.

Methods and Results

Between 2003 to 2007, 22 666 black and white participants (aged ≥45 years) without baseline CVD in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study were recruited. Cox proportional hazards regression analyses assessed the association between up to 3 measurements of elevated depressive symptoms (4‐item Center for Epidemiologic Studies Depression Scale score ≥4) and incident coronary heart disease, stroke, and CVD death adjusting for age, sex, region, income, health insurance, education, blood pressure, cholesterol, medication, obesity, diabetes mellitus, kidney disease, C‐reactive protein, corrected QT interval, atrial fibrillation, left ventricular hypertrophy, smoking, alcohol, physical inactivity, medication adherence, and antidepressant use. The participants’ average age was 63.4 years, 58.8% were female, and 41.7% black. Time‐varying depressive symptoms were significantly associated with CVD death (adjusted hazard ratio 1.30, 95% CI 1.04–1.63), with a trend toward significance for fatal and nonfatal stroke (adjusted hazard ratio 1.26, 95% CI 0.99–1.60) but not fatal and nonfatal coronary heart disease (adjusted hazard ratio 1.11, 95% CI 0.89–1.38). Race did not moderate the association between depressive symptoms and CVD.

Conclusions

Proximal depressive symptoms were associated with incident fatal and nonfatal stroke and CVD death even after controlling for multiple explanatory factors, further supporting the urgent need for timely management of depressive symptoms.

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.

Desafios à implantação do centro de leitura de eletrocardiografia no ELSA-Brasil

O eletrocardiograma é um método estabelecido de avaliação cardiovascular de baixo custo utilizado há décadas em estudos epidemiológicos de grande porte. Apesar disso, sua utilização em estudos desse tipo se constitui em desafio, especialmente quando se pretende implantar Centro de Leitura próprio. Este artigo descreve o processo, dificuldades e desafios de implantação do Centro de Leitura em eletrocardiograma no Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil). Dentre os aspectos discutidos, ressaltam-se: os critérios para escolha dos eletrocardiógrafos e da central de armazenamento e manejo dos aparelhos; o pessoal necessário; os procedimentos de aquisição e de transmissão dos eletrocardiogramas para o Centro de Leitura; os sistemas de codificação dos traçados, com ênfase para o código de Minnesota; os aspectos éticos e práticos relacionados à entrega dos laudos aos participantes do estudo; e os aspectos relacionados ao controle de qualidade.

Electrocardiographic changes associated with smoking and smoking cessation: outcomes from a randomized controlled trial

Introduction

Cardiovascular disease (CVD) can be detected and quantified by analysis of the electrocardiogram (ECG); however the effects of smoking and smoking cessation on the ECG have not been characterized.

Methods

Standard 12-lead ECGs were performed at baseline and 3 years after subjects enrolled in a prospective, randomized, placebo-controlled clinical trial of smoking cessation pharmacotherapies. ECGs were interpreted using the Minnesota Code ECG Classification. The effects of (i) smoking burden on the prevalence of ECG findings at baseline, and (ii) smoking and smoking cessation on ECG changes after 3 years were investigated by multivariable and multinomial regression analyses.

Results

At baseline, 532 smokers were (mean [SD]) 43.3 (11.5) years old, smoked 20.6 (7.9) cigarettes/day, with a smoking burden of 26.7 (18.6) pack-years. Major and minor ECG criteria were identified in 87 (16.4%) and 131 (24.6%) of subjects, respectively. After adjusting for demographic data and known CVD risk factors, higher pack-years was associated with major ECG abnormalities (p = 0.02), but current cigarettes/day (p = 0.23) was not. After 3 years, 42.9% of subjects were abstinent from smoking. New major and minor ECG criteria were observed in 7.2% and 15.6% of subjects respectively, but in similar numbers of abstinent subjects and continuing smokers (p>0.2 for both). Continuing smokers showed significant reduction in current smoking (–8.4 [8.8] cigarettes/day, p<0.001) compared to baseline.

Conclusions

In conclusion, major ECG abnormalities are independently associated with lifetime smoking burden. After 3 years, smoking cessation was not associated with a decrease in ECG abnormalities, although cigarettes smoked/day decreased among continuing smokers.

Mortality risk associated with bundle branch blocks and related repolarization abnormalities (from the Women's Health Initiative [WHI])

Electrocardiographic bundle branch block (BBB) has higher cardiac and all-cause death. However, reports on the association between BBBs and mortality in the general populations are conflicting. The aim of this study was to evaluate the risk for coronary heart disease (CHD) and all-cause death associated with left BBB (LBBB) and right BBB (RBBB) during 14 years of follow-up in 66,450 participants from the Women's Health Initiative (WHI) study. Cox proportional-hazards regression was performed for mortality risk in Women with LBBB (n = 714) and those with RBBB (n = 832). In risk models adjusted for demographic and clinical risk factors in women with cardiovascular disease (CVD), hazard ratios for CHD death were 2.92 (95% confidence interval 2.08 to 4.08, p <0.001) for LBBB and 1.62 (95% confidence interval 1.08 to 2.43, p <0.05) for RBBB, and only LBBB was a significant predictor of all-cause death (hazard ratio 1.43, 95% confidence interval 1.11 to 1.83, p <0.01). In CVD-free women, only LBBB was a significant predictor of CHD death (fully adjusted hazard ratio 2.17, 95% confidence interval 1.37 to 3.43, p <0.01), and neither blocks was predictive of all-cause death. From several repolarization variables that were significant mortality predictors in univariate risk models, after adjustment for other electrocardiographic covariates and risk factors, ST J-point depression in lead aVL ≤-30 μV in women with LBBB was an independent predictor of CHD death, with a more than fivefold increase in risk. None of the repolarization variables were independent predictors in women with RBBB. In conclusion, prevalent LBBB in CVD-free women and LBBB and RBBB in women with CVD were significant predictors of CHD death. In women with LBBB, ST J-point depression in lead aVL was a strong independent predictor of CHD death.

Age- and Gender-Normalized Coronary Incidence and Mortality Risks in Primary and Secondary Prevention

Epidemiologic differences in ischemic heart disease incidence between women and men remain largely unexplained. The reasons of women’s “protection” against coronary artery disease (CAD) are not still clear. However, there are subsets more likely to die of a first myocardial infarction. The purpose of this review is to underline different treatment strategies between genders and describe the role of classical and novel factors defined to evaluate CAD risk and mortality, aimed at assessing applicability and relevance for primary and secondary prevention. Women and men present different age-related risk patterns: it should be important to understand whether standard factors may index CAD risk, including mortality, in different ways and/or whether specific factors might be targeted gender-wise. Take home messages include: HDL-cholesterol levels, higher in pre-menopausal women than in men, are more strictly related to CAD. The same is true for high triglycerides and Lp(a). HDL-cholesterol levels are inversely related to incidence and mortality. In primary prevention the role of statins is not completely ascertained in women although in secondary prevention these agents are equally effective in both genders. Weight and glycemic control are effective to reduce cardiovascular disease (CVD) mortality in women from middle to older age. Blood pressure is strongly and directly related to CVD mortality, from middle to older age, particularly in diabetic and over weighted women. Kidney dysfunction, defined using UAE and eGFR predicts primary CVD incidence and risk in both genders. In secondary prediction, kidney dysfunction predicts sudden death in women in conjunction with left ventricular ejection fraction evaluation. Serum uric acid does not differentiate gender-related CVD incidences, although it increases with age. Age-related differences between genders have been related to loss of ovarian function traditionally and to lower iron stores more recently. QT interval, physiologically longer in women than men, may be an index of arrhythmic risk in patients with mitral valve prolapse and increased circulating levels of catecholamines. However, there are no large population-based studies to assess this. In conjunction with novel parameters, such as inflammatory markers and reproductive hormones, classical risk score in women may be implemented in the future.

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.

Use of hundreds of electrocardiographic biomarkers for prediction of mortality in postmenopausal women: the Women's Health Initiative

BACKGROUND- Simultaneous contribution of hundreds of electrocardiographic (ECG) biomarkers to prediction of long-term mortality in postmenopausal women with clinically normal resting ECGs is unknown. METHODS AND RESULTS- We analyzed ECGs and all-cause mortality in 33 144 women enrolled in the Women's Health Initiative trials who were without baseline cardiovascular disease or cancer and had normal ECGs by Minnesota and Novacode criteria. Four hundred and seventy-seven ECG biomarkers, encompassing global and individual ECG findings, were measured with computer algorithms. During a median follow-up of 8.1 years (range for survivors, 0.5 to 11.2 years), 1229 women died. For analyses, the cohort was randomly split into derivation (n=22 096; deaths, 819) and validation (n=11 048; deaths, 410) subsets. ECG biomarkers and demographic and clinical characteristics were simultaneously analyzed using both traditional Cox regression and random survival forest, a novel algorithmic machine-learning approach. Regression modeling failed to converge. Random survival forest variable selection yielded 20 variables that were independently predictive of long-term mortality, 14 of which were ECG biomarkers related to autonomic tone, atrial conduction, and ventricular depolarization and repolarization. CONCLUSIONS- We identified 14 ECG biomarkers from among hundreds that were associated with long-term prognosis using a novel random forest variable selection methodology. These biomarkers were related to autonomic tone, atrial conduction, ventricular depolarization, and ventricular repolarization. Quantitative ECG biomarkers have prognostic importance and may be markers of subclinical disease in apparently healthy postmenopausal women.

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.