The prevalence and prognostic significance of electrocardiographic abnormalities

Prevalence and Clinical Significance of Intraventricular Conduction Disturbances in Hospitalized Children

Introduction: Data on the prevalence and clinical significance of interventricular conduction disturbances (IVCDs) in children are scarce. While incomplete right bundle branch blocks (IRBBBs) seem to be the most frequent and benign findings, complete bundle blocks and fascicular blocks are often seen in children with congenital/acquired cardiac conditions. This study aims to delineate the prevalence and the diagnostic accuracy of IVCD in children admitted to a paediatric cardiology unit. Methods: Children admitted to the paediatric cardiology unit between January 2010 and December 2020 who had an ECG were included in the study. IVCDs were diagnosed according to standard criteria adjusted for age. Results: Three thousand nine hundred and ninety-three patients were enrolled. The median age was 3.1 years (IQR: 0.0-9.2 years), and 52.7% were males. IVCDs were present in 22.5% of the population: 17.4% of the population presented with IRBBBs, 4.8% with a complete right bundle branch block (CRBBB), 0.1% with a complete left bundle branch block (CLBBB), 0.2% with a left anterior fascicular block (LAFB) and 0.2% with a combination of CRBBB and LAFB. Also, 26% of children with congenital heart disease had an IVCD, and 18% of children with an IVCD had previous cardiac surgery. The overall sensitivity of IVCD in detecting a cardiac abnormality was 22.2%, with a specificity of 75.5%, a PPV of 83.1% and an NPV of 15.1%, but the values were higher for CLBBB and LAFB. Conclusions: IVCDs were present in one-fifth of children admitted to the cardiology unit. IRBBB was the most frequent disturbance, while CRBBB, CLBBB and fascicular blocks were much rarer, though they had a higher predictive value for cardiac abnormalities.

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.

Guide to the Female Student Athlete ECG: A Comprehensive Study of 3466 Young, Racially Diverse Athletes

OBJECTIVES

The 12-lead electrocardiogram (ECG) is used in the preparticipation screening examination for athletes. Despite known differences in ECG findings by sex, only QTc prolongation is given a sex-specific threshold. We hypothesize that our large dataset-with diversity in age, race, and sport participation-can be utilized to improve ECG screening in female student athletes.

METHODS

Computerized 12-lead ECGs were recorded and analyzed in female athletes who underwent preparticipation screening examination between June 2010 and September 2021. The quantitative, empirical 2017 international criteria for electrocardiographic interpretation were compared with either the 99th percentile in our cohort or the percentile that corresponded to the known disease prevalence.

RESULTS

Of 3466 female athletes with ECGs as part of preparticipation screening examination, the 2017 international criteria classified 2.1% of athletes with at least one ECG abnormality requiring cardiological evaluation. Rates were similar across age, race/ethnicity, and sporting discipline. Using ranges based on our population, 2.7% of athletes would require additional workup. Surprisingly, ST depression up to 0.03 mV was a normal finding in this cohort. If RS voltage extremes were considered findings requiring follow-up, an additional 9.6% of the athlete population would be flagged using current definitions. This number decreases to 2.7% if using the 99th percentile in this cohort.

CONCLUSION

These results highlight a difference in the reported prevalence of ECG abnormalities when comparing empirically derived thresholds to statistically derived ranges. Consideration of new metrics specific to the female athlete population has the potential to further refine athlete ECG screening.

Prevalence of major and minor electrocardiographic abnormalities and their relationship with cardiovascular risk factors in Angolans

Aims

To identify the prevalence of major and minor electrocardiographic abnormalities and their association with the main risk factors for cardiovascular disease in a population in the province of Bengo, northern Angola.

Methods

A cross-sectional community-based study was conducted and a representative random sample stratified by sex and age was selected. In total, 2379 black individuals were included in the final analysis. A standard 12-lead ECG were recorded from all participants, analyzed and processed by the University of Glasgow software and coding by the Minnesota code.

Results

22.3% of participants had minor electrocardiographic abnormalities and 4.58% major ECG abnormalities. The most common minor ECG abnormalities were abnormal T wave inversion, minor isolated ST abnormalities and premature beats. The most common major ECG abnormalities were Left ventricular hypertrophy with major ST-T abnormalities, Ventricular conduction defects and major Q-wave abnormalities. Hypertension, diabetes mellitus, hypercholesterolemia, alcohol consumption and smoking, were significantly associated with major and minor electrocardiographic abnormalities.

Conclusions

In this study several participants had minor and major electrocardiographic abnormalities. Minor electrocardiographic abnormalities were more prevalent in men and major abnormalities in women. The electrocardiographic abnormalities had significant associations with the main cardiovascular risk factors.

ECG Abnormalities and Arterial Stiffness by HIV Status among High-Risk Populations in Rakai, Uganda: A Pilot Study

Background

People living with HIV are at increased risk for cardiovascular disease (CVD). In sub-Saharan Africa, population-based data on major CVD events such as stroke and myocardial infarction are difficult to collect. The use of proxy measures could be a feasible way to better study CVD in such settings. This study aimed to determine the acceptance of incorporating ECG and arterial function measurements into a population-based cohort study and to assess the prevalence of ECG abnormalities and arterial stiffness.

Methods

A pilot study was conducted within the Rakai Community Cohort Study in Uganda on two high-risk CVD populations; one determined by age (35-49) and Framingham CVD risk scores and the other by age alone (50+). Data on ECG, arterial function, blood pressure, and HIV status were collected. The acceptability of incorporating ECG and arterial function measurements was established as an acceptance rate difference of no more than 5% to blood pressure measurements.

Results

A total of 118 participants were enrolled, 57 participants living with HIV and 61 HIV-negative participants. Both ECG measurements and arterial function were well accepted (2% difference). Left ventricular hypertrophy (LVH) and arterial stiffness (>10 m/s) were common in both participants living with HIV and HIV-negative participants across the two high-risk populations. Prevalence rates ranged from 30% to 53% for LVH and 25% to 58% for arterial stiffness. Arterial stiffness at the 11 m/s cutoff (p = 0.03) was found to be more common among participants living with HIV in the 35-49 population.

Conclusions

The incorporation of ECG and arterial function measurements into routine activities of a population-based cohort was acceptable and incorporating these proxy measures into cohort studies should be explored further. LVH and arterial stiffness were both common irrespective of HIV status with arterial stiffness potentially more common among people living with HIV.

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Prevalence of major and minor electrocardiographic abnormalities in one million primary care Latinos

This study aims to assess the prevalence of electrocardiographic abnormalities based on the Minnesota code from a large sample of 1.01 m adult Brazilian primary care patients and to evaluate its association with age, sex, and cardiovascular risk factors. A large electrocardiogram (ECG) database of such patients aged ≥18 years (mean age 52 ± 17 years-old with 60.2% female). was analyzed and the results were stratified by sex and age. The prevalence of abnormalities was more common in men and the elderly population. Major electrocardiographic abnormalities were observed in 20.2% of adults and 43.1% of elderly patients, and minor abnormalities were found in 46.0% 39.4%, respectively. For adult patients, the number and percentage of major abnormalities rise depending on the number of cardiovascular risk factors. For elderly patients, the correlation between these variables is not clear, and the percentage of major abnormalities remains stable independently of the number of risk factors.

Abnormal Electrocardiographic Findings in the Population Older Than 40 Years. Prevalence and Clinical Significance. Results of the OFRECE Study

INTRODUCTION AND OBJECTIVES

Abnormal electrocardiographic findings are highly common. The aim of this study was to analyze the prevalence of abnormal electrocardiographic patterns in the general Spanish population aged 40 years or older.

METHODS

This subanalysis of the OFRECE study selected a representative sample of the Spanish population aged 40 years or older. Clinical data and electrocardiograms were available in all participants. The electrocardiograms were read centrally. Each electrocardiogram was independently assessed by 2 trained cardiologists and, if there was disagreement, a third was consulted to reach a consensus-based diagnosis. Prior to reading the electrocardiograms, diagnostic criteria were strictly defined for each of the abnormalities analyzed. We analyzed the prevalence and clinical factors associated with cavity enlargement, conduction disorders, repolarization abnormalities, pathological Q waves, atrial and ventricular premature beats, and pre-excitation.

RESULTS

A total of 8343 individuals were evaluated, (mean age, 59.2 years; 52.4% women). Only 4074 (51.2%) participants had a completely normal electrocardiogram. The most frequent abnormalities were nonspecific repolarization abnormalities (16%) associated with coronary heart disease and atrial fibrillation; right bundle-branch block (8.1%) associated with chronic pulmonary obstructive disease; left anterior hemiblock (6.5%) related to hypertension and congestive heart failure; and long PR interval (3.7%), which was associated with coronary heart disease.

CONCLUSIONS

Electrocardiographic abnormalities are very common in the general population aged 40 years or older. Only about half of the population had a completely normal electrocardiogram.

The Electrocardiogram: Still a Useful Tool in the Primary Care Office

A 12-lead electrocardiogram (ECG) is the most commonly ordered cardiac test. Although data are not robust, guidelines recommend against performing an ECG in patients who are asymptomatic, even if they have a higher risk of developing cardiovascular disease in the long term. Conversely, patients with cardiac symptoms, including chest pain, dyspnea, palpitation, and syncope, should have an ECG performed in the office. Computerized algorithms exist ubiquitously to guide interpretation, but they can be the source of erroneous information. A stepwise approach is given to guide the primary care physician's approach to the systematic interpretation of ECG tracings.

How well is each learner learning? Validity investigation of a learning curve-based assessment approach for ECG interpretation

Learning curves can support a competency-based approach to assessment for learning. When interpreting repeated assessment data displayed as learning curves, a key assessment question is: "How well is each learner learning?" We outline the validity argument and investigation relevant to this question, for a computer-based repeated assessment of competence in electrocardiogram (ECG) interpretation. We developed an on-line ECG learning program based on 292 anonymized ECGs collected from an electronic patient database. After diagnosing each ECG, participants received feedback including the computer interpretation, cardiologist's annotation, and correct diagnosis. In 2015, participants from a single institution, across a range of ECG skill levels, diagnosed at least 60 ECGs. We planned, collected and evaluated validity evidence under each inference of Kane's validity framework. For Scoring, three cardiologists' kappa for agreement on correct diagnosis was 0.92. There was a range of ECG difficulty across and within each diagnostic category. For Generalization, appropriate sampling was reflected in the inclusion of a typical clinical base rate of 39% normal ECGs. Applying generalizability theory presented unique challenges. Under the Extrapolation inference, group learning curves demonstrated expert-novice differences, performance increased with practice and the incremental phase of the learning curve reflected ongoing, effortful learning. A minority of learners had atypical learning curves. We did not collect Implications evidence. Our results support a preliminary validity argument for a learning curve assessment approach for repeated ECG interpretation with deliberate and mixed practice. This approach holds promise for providing educators and researchers, in collaboration with their learners, with deeper insights into how well each learner is learning.

Population Prevalence and Correlates of Prolonged QT Interval: Cross-Sectional, Population-Based Study From Rural Uganda

OBJECTIVES

We aimed to estimate the prevalence and correlates of QT interval prolongation in rural Uganda.

BACKGROUND

Major electrocardiographic abnormalities, including prolonged QT interval, have been shown to be independently predictive of adverse cardiovascular events among Western populations. Cardiovascular diseases are on the rise in sub-Saharan Africa with poorly characterized context-specific risk factors. An important question is whether ECG screening might have value in cardiovascular disease risk stratification in SSA.

METHODS

We conducted a cross-sectional survey in a sample of adults participating in an ongoing whole-population cohort in Mbarara, Uganda, in 2015. Of 1,814 subjects enrolled in the parent whole-population cohort, 856 (47%) participated in the study. Participants completed 12-lead electrocardiography and cardiovascular disease risk factors assessment. We summarized sex-specific, heart rate variation-adjusted QT (QTa) defining prolonged QTa as >460 ms in women and >450 ms in men. We fit linear and logistic regression models to estimate correlates of (continuous) QTa interval length and (dichotomous) prolonged QTa. Models included inverse probability of sampling weights to generate population-level estimates accounting for study nonparticipation.

RESULTS

We assessed data from 828 participants with electrocardiograms. The weighted population mean age was 38.4 years (95% confidence interval: 36.3-40.4). The weighted population was 50.4% female, 11.5% had elevated blood pressure, and 57.6% had a high-sensitivity C-reactive protein >1 mg/dl. The population mean QTa was 409.1 ms (95% confidence interval: 405.1-413.1), and 10.3% (95% confidence interval: 7.8-13.5) met criteria for prolonged QTa. Women had a higher mean QTa (421.6 ms vs. 396.3 ms; p < 0.001), and a higher proportion of women had a prolonged QTa (14.0% vs. 9.3%; p = 0.122) than did men. In multivariable-adjusted regression models, female sex and hypertension correlated with higher mean QTa and meeting criteria for prolonged QTa, respectively.

CONCLUSIONS

QT interval prolongation is highly prevalent in rural Uganda and may be more common than in high-income settings. Female sex, age, and high blood pressure correlated with QT interval prolongation. Future work should assess whether genetic predisposition or environmental factors in sub-Saharan African populations contribute to prolonged QT and clarify consequences.

Prevalence and prognostic impact of electrocardiographic abnormalities in outpatients with extracardiac artery disease

Identifying cardiac disease in patients with extracardiac artery disease (ECAD) is essential for clinical decision-making. Electrocardiography (ECG) is an easily accessible tool to unmask subclinical cardiac disease and to risk stratify patient with or without manifest cardiovascular disease (CV). We aimed to examine the prevalence and prognostic impact of ECG changes in outpatients with ECAD. Outpatients with carotid or lower extremity artery disease (n = 435) and community-based controls (n = 397) underwent resting ECG. The patients were followed during a median of 4·8 years for CV events (hospitalization or death caused by ischaemic heart disease, cardiac arrest, heart failure, or stroke). ECG abnormalities were classified according to the Minnesota Code. Major (33% versus 15%, P<0·001) but not minor ECG abnormalities (23% versus 26%, P = 0·42) were significantly more common in patients versus controls. During the follow-up, 141 patients experienced CV events. Both major ECG abnormalities [hazard ratio (HR) 1·58, 95% confidence interval (CI) 1·11-2·25, P = 0·012] and any ECG abnormalities (HR 1·57, 95% CI 1·06-2·33, P = 0·024) were significantly associated with CV events after adjustment for potential risk factors. In conclusion, ECG abnormalities were common in these outpatients with ECAD. Major and any ECG abnormalities were independent predictors of CV events. Addition of easily accessible ECG information might be useful in risk stratification for such patients.

Frequency of different electrocardiographic abnormalities in a large cohort of Spanish workers

Aims

Our aim was to describe the electrocardiographic findings of a large sample of Spanish workers from several different employment sectors.

Methods and results

Between May 2008 and November 2010, 13 495 consecutive 12-lead resting electrocardiograms (ECGs) were obtained during health examinations of working adults aged 16-74 years in 5 cities in different regions of Spain. Of those, 13 179 ECGs suitable for interpretation were included in this study. All tracings were classified by the same cardiologist, according to the Minnesota Code criteria. The mean age of the sample was 40 years, and 73.4% were male. Frequencies of complete right bundle branch block, complete left bundle branch block, and left ventricular hypertrophy were 1.1, 0.2, and 3.6%, respectively. Major Q wave abnormalities were observed in 1.7% of the subjects, T wave abnormalities in 0.7%, early repolarization in 2.4%, and other ST segment abnormalities in 0.2%. Atrial fibrillation was present in 0.08% of the workers and atrial flutter in 0.02%. Frequencies of the Wolff-Parkinson-White pattern, Brugada pattern, long QT pattern, and short QT pattern were 0.2, 0.068, 0.038, and 0.015%, respectively.

Conclusion

This study shows the electrocardiographic findings of a large sample of Spanish workers from several different employment sectors. The frequencies of many ECG patterns related to an adverse prognosis (left ventricular hypertrophy, complete left bundle branch block, T wave abnormalities, ST segment abnormalities, and atrial fibrillation) were low.

Electrocardiographic abnormalities and mortality in aging survivors of childhood cancer: A report from the St Jude Lifetime Cohort Study

BACKGROUND

Electrocardiography (ECG), predictive of adverse outcomes in the general population, has not been studied in cancer survivors. We evaluated the prevalence of ECG abnormalities and associations with mortality among childhood cancer survivors.

METHODS

Major and minor abnormalities were coded per the Minnesota Classification system for participants in the St Jude Lifetime Cohort Study (n = 2,715) and community controls (n = 268). Odds ratios (ORs) and 95% CIs were calculated using multivariable logistic regression; and hazard ratios, using Cox proportional hazards regression.

RESULTS

Survivors were a median age of 31.3 (range 18.4-63.8) years at evaluation and 7.4 (range 0-24.8) years at diagnosis. Prior therapies included cardiac-directed radiation (29.5%), anthracycline (57.9%), and alkylating (60%) chemotherapies. The prevalence of minor ECG abnormalities was similar among survivors and controls (65.2% vs 67.5%, P = .6). Major ECG abnormalities were identified in 10.7% of survivors and 4.9% of controls (P < .001). Among survivors, the most common major abnormalities were isolated ST/T wave abnormalities (7.2%), evidence of myocardial infarction (3.7%), and left ventricular hypertrophy with strain pattern (2.8%). Anthracyclines ≥300 mg/m² (OR 1.7 95% CI 1.1-2.5) and cardiac radiation (OR 2.1 95% CI 1.5-2.9 [1-1,999 cGy], 2.6 95% CI 1.6-3.9 [2,000-2,999 cGy], 10.5 95% CI 6.5-16.9 [≥3,000 cGy]) were associated with major abnormalities. Thirteen participants had a cardiac-related death. Major abnormalities were predictive of all-cause mortality (hazard ratio 4.0 95% CI 2.1-7.8).

CONCLUSIONS

Major ECG abnormalities are common among childhood cancer survivors, associated with increasing doses of anthracyclines and cardiac radiation, and predictive of both cardiac and all-cause mortality.

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

BACKGROUND

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

METHODS AND RESULTS

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

CONCLUSION

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

The Prognostic Significance of Right Bundle Branch Block: A Meta-analysis of Prospective Cohort Studies

BACKGROUND

The prognostic significance of right bundle branch block (RBBB) is inconsistent across studies. We aimed to assess the association between RBBB (in general population and patients with heart disease) and risk of all-cause mortality, cardiac death, acute myocardial infarction (MI), and heart failure (HF).

HYPOTHESIS

RBBB may be associated with increased risk of death.

METHODS

PubMed, EMBASE, and the Cochrane Library up to February 2015 were searched for prospective cohort studies that reported RBBB at baseline and all-cause mortality, cardiac death, MI, and HF at follow-up. A meta-analysis of published data was undertaken primarily by means of fixed-effects models.

RESULTS

Nineteen cohort studies including 201 437 participants were included with a mean follow-up period ranging from 1 to 246 months. For general population with RBBB, the pooled adjusted hazard ratio (HR) for all-cause mortality was 1.17 (95% confidence interval [CI]: 1.03-1.33) compared with no BBB. General population with RBBB had an increased risk of cardiac death (HR: 1.43, 95% CI: 1.17-1.74). For patients with RBBB and acute MI, the pooled risk ratio was 2.31 (95% CI: 2.13-2.49) for in-hospital mortality, 2.85 (95% CI: 2.46-3.30) for 30-day mortality, and 1.96 (95% CI: 1.59-2.42) for longer-term mortality. For acute HF patients, the pooled risk ratio of all-cause mortality was 1.11 (95% CI: 1.06-1.16), and for chronic HF patients it was 1.75 (95% CI: 1.38-2.22).

CONCLUSIONS

Right bundle branch block is associated with an increased risk of mortality in general population and patients with heart disease.

The Prevalence of Cardiac Risk Factors in Men with Localized Prostate Cancer Undergoing Androgen Deprivation Therapy in British Columbia, Canada

Background. While androgen deprivation therapy (ADT) reduces the risk of prostate cancer-specific mortality in high-risk localized prostate cancer, it adversely affects cardiovascular (CV) risk factor profiles in treated men. Methods. We retrospectively reviewed the charts of 100 consecutive men with intermediate- or high-risk localized prostate cancer referred to the British Columbia Cancer Agency for ADT. Data on CV risk factors and disease were collected and Framingham risk scores were calculated. Results. The median age of the study cohort was 73 years. Established cardiovascular disease was present in 25% of patients. Among patients without established CV disease, calculated Framingham risk was high in 65%, intermediate in 33%, and low in 1%. Baseline hypertension was present in 58% of patients, dyslipidemia in 51%, and diabetes or impaired glucose tolerance in 24%. Hypertension was more prevalent in the study cohort than in an age- and sex-matched population sample (OR 1.74, P = 0.006); diabetes had a similar prevalence (OR 0.93, P = 0.8). Conclusions. Patients receiving ADT have a high prevalence of cardiovascular disease and risk factors and are more likely to be hypertensive than population controls. Low rates of CV risk screening suggest opportunities for improved primary and secondary prevention of CV disease in this population.

T-wave inversion and mortality risk

OBJECTIVE

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

RESULTS

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

CONCLUSION

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

The impact of hepatitis C infection on ischemic heart disease via ischemic electrocardiogram

BACKGROUND

Hepatitis C virus (HCV) infection is a serious disease worldwide and it leads to several serious hepatic sequels. Some studies find possible correlation between HCV and ischemic heart disease in retrospective observations. Based on lacked community-based evidence, the study aims to assess correlation between ischemic heart disease and chronic HCV infection via electrocardiogram (ECG) because its abnormalities is strongly associating with cardiovascular disease mortality.

METHODS

The population was from one community health examination in December 2010 in a southern village of Taiwan. A total of 9856 participants were evaluated and finally 5015 eligible residents with age older than 40 years were included. The baseline characteristics and laboratory data in nonischemic ECG and ischemic ECG groups were compared, and multivariate-adjusted analysis was used to evaluate the risks to ischemic ECG.

RESULTS

The higher prevalence of hypertension, metabolic syndrome and even HCV infection (25.3% versus 11.6%; P < 0.001) in ischemic ECG group than those in nonischemic ECG group. In the multivariate adjusted analysis, HCV infection would lead to a 1.759-fold risk to ischemic ECG when compared with non-HCV subjects.

CONCLUSIONS

HCV was strongly associated with ischemic ECG findings in this community study, and it could be a nonconventional risk factor for coronary artery disease.

Screening strategies for cardiovascular disease in asymptomatic adults

The purpose of this article is to update the primary care community on the evidence and guidelines for cardiovascular disease screening in a general-risk adult population, with the goal of assisting clinicians in developing an evidence-based approach toward screening. This article discusses global risk assessment and screening strategies, including blood pressure, lipids, C-reactive protein, homocysteine, coronary artery calcium score, carotid intima-media thickness, ultrasound of the abdominal aorta, and electrocardiography.

Electrocardiograms of adult outpatients followed-up in basic health care units in the community of the South region of São Paulo City

OBJECTIVE

The electrocardiogram (ECG) is an important, available, and inexpensive diagnostic tool to assess cardiac symptoms. Few studies address the prevalence of ECG abnormalities or changes of a normal tracing in ECG in outpatients. Our objective was to evaluate ECGs of adult outpatients to determine whether changes from a normal tracing could disclose the patients' cardiovascular health status.

METHODS

We evaluated all elective ECGs obtained in adult outpatients, from January 2009 to January 2010, at a municipal hospital in the city of São Paulo, Brazil. Electrocardiography was performed with a 3-channel, 12-lead machine (Dixtal Cardio-page EP-3, Dixtal Biomedica, São Paulo, Brazil), and results were interpreted by a cardiologist.

RESULTS

Electrocardiography was performed in 3567 adult outpatients, 62.5% of whom were women, with a mean age of 51 years (standard deviation [SD] = 16 years). Of the 1918 patients whose ECGs showed abnormalities (mean age = 56 years, SD = 15 years), 1137 were women. Electrocardiographic changes were found in 1184 of the patients. Minor changes were found in 38.3% of patients. A total of 3133 changes were found in 1918 abnormal ECG results. There was a statistical difference related to sex and age, and abnormal ECG results were more frequent in men. There was a high prevalence of abnormal ECG results in the population studied.

CONCLUSIONS

There were more ECGs obtained from women; however, men and elderly patients more frequently had abnormal ECG results.

Major and minor electrocardiographic abnormalities and their association with underlying cardiovascular disease and risk factors in Hispanics/Latinos (from the Hispanic Community Health Study/Study of Latinos)

The association of electrocardiographic (ECG) abnormalities with cardiovascular disease and risk factors has been extensively studied in whites and African-Americans. Comparable data have not been reported in Hispanics/Latinos. The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a multicenter, community-based, prospective cohort study of men and women of diverse backgrounds aged 18 to 74 years who self-identified as Hispanic/Latinos. Participants (n = 16,415) enrolled from March 2008 to June 2011. We describe the prevalence of minor and major ECG abnormalities and examined their cross-sectional associations with cardiovascular disease and risk factors. The Minnesota code criteria were used to define minor and major ECG abnormalities. Previous cardiovascular disease and risk factors were based on data obtained at baseline examination. Significant differences in prevalent ECG findings were found between men and women. Major ECG abnormalities were present in 9.2% (95% confidence interval 8.3 to 10.1) of men and 6.6% (95% confidence interval 5.8 to 7.3) of women (p <0.0001). The odds of having major ECG abnormalities significantly increased with age, presence of ≥3 cardiovascular risk factors, and prevalent cardiovascular disease, in both men and women. Significant differences in major ECG abnormalities were found among the varying groups; Puerto Ricans and Dominicans had more major abnormalities compared with Mexican men and women. In conclusion, in a large cohort of Hispanic/Latino men and women, prevalence of major abnormalities was low, yet strong associations of major ECG abnormalities with cardiovascular disease and risk factors were observed in both men and women.

Long-term outcomes of pediatric sinus bradycardia

OBJECTIVES

To delineate the long-term outcomes and mechanisms of pediatric sinus bradycardia.

STUDY DESIGN

Participants with sinus bradycardia who were identified from a survey of 432,166 elementary and high school students, were enrolled 10 years after the survey. The clinical course, heart rate variability, and hyperpolarization-activated cyclic nucleotide-gated potassium channel 4 (HCN4) gene were assessed.

RESULTS

A total of 104 (male:female was 60:44; prevalence, 0.025%) participants were observed to have sinus bradycardia at age 15.5 ± 0.2 years with a mean heart rate of 48.4 ± 0.4 beats per minute; 86 study participants (83%) responded to clinical assessment and 37 (36%) underwent laboratory assessment. Athletes composed 37.8% of the study participants. During the extended 10-year follow-up, 15 (17%) of the participants had self-limited syncopal episodes, but none had experienced life-threatening events. According to Holter recordings, none of the participants had heart rate <30 beats per minute or a pause longer than 3 seconds. Compared with 67 age- and sex-matched controls, the variables of heart rate based on the spectral and time domain analysis of the participants with sinus bradycardia were all significantly higher, indicating higher parasympathetic activity. The results of mutation analysis were negative in the HCN4 gene in all of our participants.

CONCLUSIONS

The long-term outcomes of the children and adolescents with sinus bradycardia identified using school electrocardiographic survey are favorable. Parasympathetic hyperactivity, instead of HCN4 gene mutation, is responsible for the occurrence of sinus bradycardia.

The Moli-sani project: computerized ECG database in a population-based cohort study

Computerized electrocardiogram (ECG) acquisition and interpretation may be extremely useful in handling analysis of data from large cohort studies and exploit research on the use of ECG data as prognostic markers for cardiovascular disease. The Moli-sani project (http://www.moli-sani.org) is a population-based cohort study aiming at evaluating the risk factors linked to chronic-degenerative disease with particular regard to cardiovascular disease and cancer and intermediate metabolic phenotypes such as hypertension, diabetes, dyslipidemia, obesity, and metabolic syndrome. Between March 2005 and April 2010, 24 325 people aged 35 years or older, living in the Molise region (Italy), were randomly recruited. A follow-up based on linkage with hospital discharge records and mortality regional registry and reexamination of the cohort is ongoing and will be repeated at prefixed times. Each subject was administered questionnaires on personal and medical history, food consumption, quality of life (FS36), and psychometry. Plasma serum, cellular pellet, and urinary spots were stored in liquid nitrogen. Subjects were measured blood pressure, weight, height, and waist and hip circumferences, and underwent spirometry to evaluate pulmonary diffusion capacity, gas diffusion, and pulmonary volumes. Standard 12-lead resting ECG was performed by a Cardiette ar2100-view electrocardiograph and tracings stored in digital standard communication protocol format for subsequent analysis. The digital ECG database of the Moli-sani project is currently being used to assess the association between physiologic variables and pathophyiosiologic conditions and parameters derived from the ECG signal. This computerized ECG database represents a unique opportunity to identify and assess prognostic factors associated with cardiovascular and metabolic diseases.

T-wave inversion on electrocardiogram is related to the risk of acute coronary syndrome in the general population

BACKGROUND

T-wave inversion (TWI) is a frequently encountered electrocardiographic (ECG) finding during routine medical examination of asymptomatic individuals, and of patients with various clinical conditions. However, the role of isolated TWI in the prediction of acute coronary syndrome (ACS) in the community has not been extensively studied. We investigated the relationship between TWI in routine ECG and the risk for ACS in the general population.

METHODS

This study is based on a random sample of 1997 men aged 42-60 years in Eastern Finland. Electrocardiograms recorded at rest were classified using the Minnesota codes. The association between isolated TWI and ACS was determined using a multivariable adjusted Cox proportional hazard model.

RESULTS

Negative T-waves were present in 3.6% of the participants. During an average follow-up of 20 years, a total of 493 ACS events were registered. After adjusting for age, TWI was associated with a 3.10-fold (95% confidence interval (CI) 2.21-4.32) risk for ACS. After additional adjustment for previously known coronary risk factors, TWI remained statistically significant in predicting ACS (relative risk 2.23; 95% CI 1.57-3.15). Negative T-waves was one of the strongest risk markers for ACS compared with other ECG-based variables such as left ventricular hypertrophy, previous Q-wave and prolonged QRS duration.

CONCLUSION

TWI has a strong and independent predictive value for ACS in the general population.

Association of major and minor ECG abnormalities with coronary heart disease events

CONTEXT

In populations of older adults, prediction of coronary heart disease (CHD) events through traditional risk factors is less accurate than in middle-aged adults. Electrocardiographic (ECG) abnormalities are common in older adults and might be of value for CHD prediction.

OBJECTIVE

To determine whether baseline ECG abnormalities or development of new and persistent ECG abnormalities are associated with increased CHD events.

DESIGN, SETTING, AND PARTICIPANTS

A population-based study of 2192 white and black older adults aged 70 to 79 years from the Health, Aging, and Body Composition Study (Health ABC Study) without known cardiovascular disease. Adjudicated CHD events were collected over 8 years between 1997-1998 and 2006-2007. Baseline and 4-year ECG abnormalities were classified according to the Minnesota Code as major and minor. Using Cox proportional hazards regression models, the addition of ECG abnormalities to traditional risk factors were examined to predict CHD events.

MAIN OUTCOME MEASURE

Adjudicated CHD events (acute myocardial infarction [MI], CHD death, and hospitalization for angina or coronary revascularization).

RESULTS

At baseline, 276 participants (13%) had minor and 506 (23%) had major ECG abnormalities. During follow-up, 351 participants had CHD events (96 CHD deaths, 101 acute MIs, and 154 hospitalizations for angina or coronary revascularizations). Both baseline minor and major ECG abnormalities were associated with an increased risk of CHD after adjustment for traditional risk factors (17.2 per 1000 person-years among those with no abnormalities; 29.3 per 1000 person-years; hazard ratio [HR], 1.35; 95% CI, 1.02-1.81; for minor abnormalities; and 31.6 per 1000 person-years; HR, 1.51; 95% CI, 1.20-1.90; for major abnormalities). When ECG abnormalities were added to a model containing traditional risk factors alone, 13.6% of intermediate-risk participants with both major and minor ECG abnormalities were correctly reclassified (overall net reclassification improvement [NRI], 7.4%; 95% CI, 3.1%-19.0%; integrated discrimination improvement, 0.99%; 95% CI, 0.32%-2.15%). After 4 years, 208 participants had new and 416 had persistent abnormalities. Both new and persistent ECG abnormalities were associated with an increased risk of subsequent CHD events (HR, 2.01; 95% CI, 1.33-3.02; and HR, 1.66; 95% CI, 1.18-2.34; respectively). When added to the Framingham Risk Score, the NRI was not significant (5.7%; 95% CI, -0.4% to 11.8%).

CONCLUSIONS

Major and minor ECG abnormalities among older adults were associated with an increased risk of CHD events. Depending on the model, adding ECG abnormalities was associated with improved risk prediction beyond traditional risk factors.

The potential yield of ECG screening of hypertensive patients: the Utrecht Health Project

OBJECTIVE

Several guidelines for hypertension and cardiovascular risk management recommend an ECG in hypertensive patients to improve risk prediction. We estimated the prevalence of clinically relevant ECG abnormalities and the number needed to screen (NNS) with a routine ECG to prevent the occurrence of one death in the next 10 years conditional on adequate treatment and follow-up.

METHODS

The study population consisted of 866 hypertensive participants recruited from the Utrecht Health Project (UHP), a dynamic population study in Utrecht. Baseline measurements included an ECG and the risk factors that enable a Systematic COronary Risk Evaluation (SCORE) risk estimation for each participant. ECGs were interpreted using Modular ECG Analysis System for computerized recognition of ECG abnormalities. NNS to prevent one death was computed by the reciprocal of the prevalence of the ECG abnormalities multiplied by number needed to treat to prevent one death when the ECG abnormality is managed according to the prevailing clinical guidelines.

RESULTS

The population consisted of 54.2% men with a mean age of 53.2 years (SD 11.5). The prevalence of ECG abnormalities was 17.6 [n = 95% confidence interval (CI) 15.0-20.1]. Prevalence of atrial fibrillation or prior myocardial infarction was 2.1% (95%CI 1.1-3.0) and of other ECG abnormalities related to increased cardiovascular disease risk 15.4% (95%CI 13.1-17.9). NNS to prevent one death from cardiovascular disease within 10 years was estimated at 260 (95%CI 220-308).

CONCLUSION

Our findings support the existing recommendations to routinely record an ECG in unselected hypertensive patients as the prevalence of relevant abnormalities is considerable and NNS to prevent one death is lower than that in other widely accepted tests.

Prevalence of electrocardiographic abnormalities in a middle-aged, biracial population: Coronary Artery Risk Development in Young Adults study

BACKGROUND

Few studies to date have described the prevalence of electrocardiographic (ECG) abnormalities in a biracial middle-aged cohort.

METHODS AND RESULTS

Participants underwent measurement of traditional risk factors and 12-lead ECGs coded using both Minnesota Code and Novacode criteria. Among 2585 participants, of whom 57% were women and 44% were black (mean age 45 years), the prevalence of major and minor abnormalities was significantly higher (all P < .001) among black men and women compared to whites. These differences were primarily due to higher QRS voltage and ST/T-wave abnormalities among blacks. There was also a higher prevalence of Q waves (Minnesota Code 1-1, 1-2, 1-3) than described by previous studies. These racial differences remained after multivariate adjustment for traditional cardiovascular (CV) risk factors.

CONCLUSIONS

Black men and women have a significantly higher prevalence of ECG abnormalities, independent of traditional cardiovascular risk factors, than whites in a contemporary cohort of middle-aged participants.

Prevalence and prognostic value of poor R-wave progression in standard resting electrocardiogram in a general adult population. The Health 2000 Survey

AIMS

We examined the prevalence and prognostic impact of poor R-wave progression (PRWP) in a standard electrocardiogram (ECG) in a general population.

METHODS

Data and standard resting ECG recording were collected from a large nationally representative (random sample) health examination survey conducted in Finland in 2000-2001. The final study population consisted of 5613 individuals.

RESULTS

The prevalence of PRWP (defined as RV3 < or = 3 mm and RV2 < or = RV3) was 7.0% in women and 2.7% in men (P< or = 0.001 for difference). During follow-up of 70 +/- 9 months (mean +/- SD), 317 patients died (5.6%). Both all-cause and cardiovascular mortality was higher in the group with PRWP than in those without PRWP in both women and men. In Cox regression analysis after adjustment for age, hypertension, diabetes, previous myocardial infarction, and coronary heart disease, the relative risk for all-cause mortality for PRWP was 1.69 (95% CI 0.89-3.22, P=0.112) for men and 2.00 (95% CI 1.28-3.13, P=0.002) for women. For cardiovascular mortality the relative risk for individuals with PRWP was 1.85 (0.74-4.65, P=0.19) for men and 3.02 (1.54-5.93, P=0.001) for women.

CONCLUSIONS

PRWP is a common ECG finding and predicts risk for total and cardiovascular mortality in women in a general population.

A simplified clinical electrocardiogram score for the prediction of cardiovascular mortality

BACKGROUND

Electrocardiogram (ECG) scores have been demonstrated to predict CV mortality but they are rarely utilized clinically.

OBJECTIVE

Develop a simple score consisting of adding classical ECG abnormalities to make the ECG a more convenient prognostic tool.

METHODS

Resting ECGs of 29,320 outpatient male veterans from the Palo Alto Veteran Affairs Healthcare System (PAVHS) collected between 1987 and 2000 were computer analyzed with an average follow-up of 7.5 y. Twelve classic ECG abnormalities were chosen on the basis of prevalence and corresponding relative risks, including left and right bundle branch block, diagnostic Q waves, intraventricular conduction defect, atrial fibrillation, left atrial abnormality, left and right axis deviation, left and right ventricular hypertrophy, ST depression, and abnormal QTc interval. A simple score derived from the summation of these criteria was then entered into an age and heart rate adjusted Cox analysis.

RESULTS

There was a progressive increase in risk of death as the number of ECG abnormalities increased. The relative risks for 1, 2, 3, 4, and 5 ECG abnormalities were 1.8 (CI 1.6-2.0), 2.4 (CI 2.2-2.7), 3.6 (CI 3.2-4.1), 4.5 (CI 3.8-5.4), and 6.0 (CI 4.7-7.8) respectively (p < 0.001). The age-adjusted hazard ratio for CV mortality was 6.0 when there were five or more ECG abnormalities present.

CONCLUSION

Summing the number of classical ECG abnormalities provides a powerful predictor of CV mortality independent of age, standard risk factors, and clinical status.

[Standard-ECG]

The ECG is still the basis of technical investigations in cardiology. New descriptions and interpretations have been developed for left ventricular hypertrophy, Q-wave, arrhythmogenic diseases such as long and short QT syndrome, Brugada syndrome, syndrome of early repolarization, and arrhythmogenic right ventricular disease.

The prognostic value of T wave amplitude in lead aVR in males

BACKGROUND

Since there is an uncertainty regarding which of the 12 leads provides the most information, we investigated the association between repolarization phenomenon in all of the 12 leads and cardiovascular (CV) mortality.

METHODS

Retrospective cohort study was performed at Palo Alto Veterans Affairs Medical Center, Palo Alto, California, which included 24,270 consecutive male veterans with ECGs obtained for clinical reasons from 1987 to 2000. Analysis of computerized 12-lead resting ECGs was performed of all subjects excluding inpatients, patients with atrial fibrillation, WPW, QRS duration > 120 ms, and paced rhythms. Average follow-up was 7.5 years during which time there were 1859 CV deaths.

RESULTS

While ST segment measurements in aVR were univariately predictive of CV death, T wave amplitude superseded them in multivariate survival analysis. In addition, T wave amplitude in aVR outperformed repolarization measurements in all other leads as well as other ECG criteria (Q waves, damage scores, LVH) for predicting CV mortality. As T wave amplitude became less negative in aVR, there was a progressive increase in relative risk (RR). When the T waves in aVR had a positive deflection (i.e., upward pointing) the RR for CV death was 5.0.

CONCLUSIONS

T wave amplitude in lead aVR is a powerful prognostic marker for estimating risk of CV death. Upward pointing T waves (a simple visual criterion) was prevalent (7.3% of a clinical population) and was associated with an annual CV mortality of 3.4% and a risk of five times.

Cardiac conduction disturbance detected in a pediatric population

OBJECTIVE

To delineate the prevalence and clinical implications of cardiac conduction disturbance (CCD) in school-age children.

STUDY DESIGN

Between 1999 and 2001, a citywide survey of 432,166 elementary and high school students had been performed in Taipei by questionnaire, electrocardiography, phonocardiography, and physical examination. Patients with any abnormalities on this survey were referred for final diagnosis.

RESULTS

After excluding those with congenital heart disease (CHD), the prevalence of CCD was 0.75%, higher in males than in females (0.78% vs 0.71%). Incomplete right bundle branch block (IRBBB; 0.32%), complete right bundle branch block (CRBBB; 0.11%), ventricular premature contraction (0.11%), and Wolff-Parkinson-White syndrome (0.067 %) were the most common diagnoses. Second-degree atrioventricular block, IRBBB, CRBBB, and intraventricular conduction delay were more common in males; and atrial premature contraction was more common in females. The prevalence of CCD increased with age, from 0.48% in elementary school students to 0.97% in high school students. After detection of CCD, 39 patients with previously undiagnosed atrial septal defect (ASD) and 15 high-risk patients were found. The sensitivity of IRBBB in screening for ASD was 34.67%.

CONCLUSIONS

The prevalence of CCD in children without CHD was 0.75%. Detection of CCD helped identify patients with unrecognized ASD and high-risk cardiac patients.

Age and follow-up time affect the prognostic value of the ECG and conventional cardiovascular risk factors for stroke in adult men

OBJECTIVES

To explore whether the predictive power of mid-life ECG abnormalities and conventional cardiovascular risk factors for future stroke change over a 30-year follow-up period, and whether a repeated examination improves their predictive power.

DESIGN AND SETTING

Longitudinal population-based study.

PARTICIPANTS

2,322 men aged 50 years, with a follow-up period of 30 years. 1,221 subjects were re-examined at age 70 years

MAIN OUTCOME MEASURE

Risk for fatal and non-fatal stroke during three decades of follow-up. Investigations included resting ECG and traditional cardiovascular risk factors.

RESULTS

When measured at age 50 years, ST segment depression and T wave abnormalities, together with ECG-left ventricular hypertrophy, were of importance only during the first 20 years, but regained importance when re-measured at age 70 years. Blood pressure was a significant predictor for stroke over all three decades of follow-up. In elderly people only, there is evidence that apolipoprotein A1 may protect from future stroke.

CONCLUSION

Mid-life values for blood pressure and ECG abnormalities retain their predictive value over long follow-up periods even though they improved in predictive power when re-measured in elderly people. Despite lower prevalence, ECG abnormalities had greater impact at age 50 years than at age 70 years. By contrast, apolipoprotein A1 was protective for future stroke only at age 70 years.

Measurement of coronary calcium scores or exercise testing as initial screening tool in asymptomatic subjects with ST-T changes on the resting ECG: an evaluation study

BACKGROUND

Asymptomatic subjects at intermediate coronary risk may need diagnostic testing for risk stratification. Both measurement of coronary calcium scores and exercise testing are well established tests for this purpose. However, it is not clear which test should be preferred as initial diagnostic test. We evaluated the prevalence of documented coronary artery disease (CAD) according to calcium scores and exercise test results.

METHODS

Asymptomatic subjects with ST-T changes on a rest ECG were selected from the population based PREVEND cohort study and underwent measurement of calcium scores by electron beam tomography and exercise testing. With calcium scores > or =10 or a positive exercise test, myocardial perfusion imaging (MPS) or coronary angiography (CAG) was recommended. The primary endpoint was documented obstructive CAD (>/=50% stenosis).

RESULTS

Of 153 subjects included, 149 subjects completed the study protocol. Calcium scores > or =400, 100-399, 10-99 and <10 were found in 16, 29, 18 and 86 subjects and the primary endpoint was present in 11 (69%), 12 (41%), 0 (0%) and 1 (1%) subjects, respectively. A positive, nondiagnostic and negative exercise test was present in 33, 27 and 89 subjects and the primary endpoint was present in 13 (39%), 5 (19%) and 6 (7%) subjects, respectively. Receiver operator characteristics analysis showed that the area under the curve, as measure of diagnostic yield, of 0.91 (95% CI 0.84-0.97) for calcium scores was superior to 0.74 (95% CI 0.64-0.83) for exercise testing (p = 0.004).

CONCLUSION

Measurement of coronary calcium scores is an appropriate initial non-invasive test in asymptomatic subjects at increased coronary risk.

Persistent ischaemic ECG abnormalities on repeated ECG examination have important prognostic value for cardiovascular disease beyond established risk factors: a population-based study in middle-aged men with up to 32 years of follow-up

OBJECTIVE

To determine the effect of new, persistent or reverted ischaemic ECG abnormalities at ages 50 and 70 years on the risk of subsequent cardiovascular disease.

DESIGN, SETTING AND PARTICIPANTS

A prospective community-based observational cohort of 50-year-old men in Sweden, followed for 32 years. 2322 men of age 50 years participated in 1970-3, and 1221 subjects were re-examined at the age of 70 years.

MAIN OUTCOME MEASURES

Myocardial infarction (MI), cardiovascular mortality and overall mortality.

RESULTS

At 50 years of age, after adjusting for established conventional risk factors, T wave abnormalities, ST segment depression, major Q/QS pattern and ECG-left ventricular hypertrophy were all found to be independent risk factors for the main outcome measures during the 32 years of follow-up. When ECG variables were re-measured at 70 years of age, they were still found to be independent risk factors for the mortality outcomes, but lost in significance for prediction of MI. Regarding mortality, it was twice as dangerous to have persistent T wave abnormalities (HR 4.63; 95% CI 2.18 to 9.83) or ST segment depression (HR 5.66; 95% CI 1.77 to 18.1), as with new T wave abnormalities (HR 2.20; 95% CI 1.48 to 3.29) or ST segment depression (HR 2.55; 95% CI 1.74 to 3.75), developing between ages 50 and 70 years. The addition of "ECG indicating ischaemia" significantly increased the predictive power of the Framingham score (p<0.001).

CONCLUSIONS

It is worthwhile to obtain serial ECGs for proper risk assessment, since persistent ST-T abnormalities carried twice as high a risk for future mortality compared with new or reverted abnormalities.

Clinical significance of minor nonspecific ST-segment and T-wave abnormalities in asymptomatic subjects: a systematic review

The purpose of the study is to examine the prevalence and significance of minor nonspecific ST-segment and T-wave abnormalities (NSSTTA) in the prediction of future cardiovascular disease (CVD) events. Minor NSSTTA are commonly encountered in clinical practice. To date, there have been no systematic reviews focusing on the prevalence and prognostic importance of these findings. Literature searches of MEDLINE (1966-2005) were supplemented with searches of bibliographies from key articles. We focused on isolated minor NSSTTA in healthy middle-aged or elderly populations, including men, women, blacks, and whites, and the association of isolated minor NSSTTA with incident cardiovascular and coronary events. Isolated minor NSSTTA are common in middle-aged white men (ranging from 3.6% to 10.3%), and seem to be even more prevalent in women, blacks, and the elderly. In the 3 studies that examined isolated minor NSSTTA, the multivariable-adjusted hazard ratios for coronary mortality ranged from 1.24 to 1.66. Although gender, race, and age-specific differences in the prognostic significance of minor NSSTTA are not clear because of limited data, minor NSSTTA in asymptomatic patients are an important risk factor for coronary and cardiovascular mortality, independent of traditional risk factors. Minor NSSTTA are prevalent in asymptomatic individuals, and they confer increased risk for CVD and coronary heart disease (CHD), independent of traditional risk factors. Future studies with standardized methodology are needed to elucidate the physiological significance of minor NSSTTA and to further describe gender, race, and age-related differences in the prevalence and prognostic significance of minor NSSTTA.

Subclinical coronary atherosclerosis and resting ECG abnormalities in an unselected general population

OBJECTIVES

Exposure to cardiovascular (CV) risk factors may result in coronary atherosclerosis and myocardial disease, which is reflected in the extent of coronary artery calcification (CAC) and resting ECG abnormalities, respectively. We studied the association of CAC with ECG abnormalities in a general population without myocardial infarction or revascularization.

METHODS

The total cohort of 4814 subjects (45-75 years) were randomly selected from the general population for the Heinz Nixdorf Recall Study, an ongoing study designed to assess the prognostic value of modern risk stratification methods. In addition to measuring standard risk factors, digitized resting ECGs and the EBT-based Agatston score were obtained. Subjects were separated into those without (n=1929) and with CV disease (CVD) or treated risk factors (tRF) (n=2558).

RESULTS

In both groups, a positive CAC-score was more frequent and CAC-scores were higher in men and women with ECG abnormalities as compared to those with normal ECGs (p<0.05 each). In persons without CVD/tRF, a CAC > or =75th percentile was more frequent in those with LVH (42.4%) and QTc >440 ms (34.2%) as compared to normal ECGs (23.0%, p<0.01 for both). In persons with CVD/tRF, a CAC-score > or =75th percentile was found in subjects with A-Fib (46.3%), borderline-LVH (39.1%), ECG signs of MI (40.5%) and major ECG abnormalities (40.3%) versus 31.2% in those with normal ECGs (p<0.03 for all). In multivariate analysis, LVH (p=0.025) and major ECG abnormalities (p=0.04) remained independently associated with CAC in subjects without and with CVD/tRF, respectively.

CONCLUSIONS

ECG-based evidence of myocardial disease is often associated with an elevated CAC burden, suggesting a link between epicardial and myocardial manifestations of risk factor exposure. The association of CAC burden with different ECG abnormalities in different clinical groups may have implications for the interpretation of the resting ECG and CAC burden in risk stratification.

High prevalence of markers of coronary heart disease among Greenland Inuit

OBJECTIVE

It is a common notion that coronary heart disease (CHD) is rare among the Inuit, possibly due to a high intake of omega-3-fatty acids. The scientific evidence for this is weak and to some extent based on uncertain mortality statistic. The aim of this study was to assess the prevalence of markers of CHD among Greenland Inuit, and to study associations between markers of CHD and behavioral and biological variables.

DESIGN

We studied prevalence of angina pectoris (AP), self-reported myocardial infarction (MI), and ECG defined MI and ischaemia in a population survey among 1316 Inuit living in Greenland. Blood tests were supplemented by structured interviews, anthropometry, and measurements of blood pressure, and the participants received an oral glucose tolerance test.

RESULTS

The prevalence of symptomatic CHD (AP, self-reported MI) was 7.3% among men and 6.9% among women, and 12.2% and 13.4% of men and women had ischaemic ECG changes. The overall prevalence of CHD (AP+self-reported MI+ECG defined MI) was 10.8% in men and 10.2% in women. The highest prevalence was observed in the least westernized areas in Greenland. Physical inactivity, low education, dyslipidemia, hypertension and diabetes were associated with CHD.

CONCLUSION

The prevalence of markers of CHD was not different from that in Western populations. The Inuit is a population undergoing rapid social and health transitions, with the emergence of cardiovascular risk factors, and there is a need for critical rethinking of cardiovascular epidemiology in this population.

Perioperative cardiac risk: pathophysiology, assessment and management

Cardiac complications are the leading cause of perioperative morbidity and mortality following noncardiac surgery. The annual cost of perioperative cardiovascular events exceeds 20 billion US dollars. A strategic preoperative evaluation holds the potential to reduce perioperative cardiac events and healthcare costs; however, our current understanding of the pathophysiological basis of postoperative acute coronary syndromes is limited. Although significant advances continue to facilitate early and reliable noninvasive detection of high-risk coronary anatomy, the most appropriate interventions remain unclear. Pharmacotherapy, revascularization, safer anesthesia and early detection of perioperative heart failure may all reduce perioperative morbidity and mortality, although the evidence base is incomplete and controversial. A close working relationship between the primary care physician, cardiologist, surgeon and anesthesiologist will facilitate rational, tailored and optimized management decisions that constitute our best opportunity to reduce perioperative cardiovascular risk.

Impact of follow-up time and re-measurement of the electrocardiogram and conventional cardiovascular risk factors on their predictive value for myocardial infarction

OBJECTIVE

To explore if the predictive power of mid-life electrocardiogram (ECG) abnormalities and conventional cardiovascular risk factors for future myocardial infarction, change over a 30-year follow-up period and if repeated examination improves their predictive power.

DESIGN AND SETTING

Longitudinal population-based study.

PARTICIPANTS

A total of 2322 men aged 50 years, with a total follow-up period of 30 years and 1221 subjects were re-examined at age of 70 years.

MAIN OUTCOME MEASURE

Risk for fatal and nonfatal myocardial infarction (n = 470) analysed at age 50 and 70 years, and separately for 1-10, 11-20 and 21-30 years after first examination. Investigations included a 12-lead ECG, blood pressure, body mass index, smoking habits, and glucose and lipid variables.

RESULTS

Whilst high blood pressure and dyslipidaemia variables, such as apolipoprotein B/apolipoprotein A1 ratio, measured at age 50 showed an almost unchanged predictive power during the three decades of follow up, ECG abnormalities, insulin and BMI were only significant predictors during the two first decades of follow up. Despite increased prevalences of ECG abnormalities and obesity with age, they predicted for future myocardial infarction in midlife only whilst fasting insulin and smoking regained their predictive power when re-measured at age 70.

CONCLUSION

Whilst hypertension and dyslipidaemia were consistent as risk factors, length of follow-up period and age at baseline investigations affected the predictive power of ECG abnormalities, fasting insulin, BMI and smoking. In the elderly, ECG abnormalities did not contribute to the prediction of myocardial infarction but smoking and fasting insulin may be important in the pathophysiology leading to MI especially in this age group.