Exercise cardiac power and the risk of sudden cardiac death in a long-term prospective study

Risk Prediction for Sudden Cardiac Death in the General Population: A Systematic Review and Meta-Analysis

Objective: Identification of SCD risk is important in the general population from a public health perspective. The objective is to summarize and appraise the available prediction models for the risk of SCD among the general population. Methods: Data were obtained searching six electronic databases and reporting prediction models of SCD risk in the general population. Studies with duplicate cohorts and missing information were excluded from the meta-analysis. Results: Out of 8,407 studies identified, fifteen studies were included in the systematic review, while five studies were included in the meta-analysis. The Cox proportional hazards model was used in thirteen studies (96.67%). Study locations were limited to Europe and the United States. Our pooled meta-analyses included four predictors: diabetes mellitus (ES = 2.69, 95%CI: 1.93, 3.76), QRS duration (ES = 1.16, 95%CI: 1.06, 1.26), spatial QRS-T angle (ES = 1.46, 95%CI: 1.27, 1.69) and factional shortening (ES = 1.37, 95%CI: 1.15, 1.64). Conclusion: Risk prediction model may be useful as an adjunct for risk stratification strategies for SCD in the general population. Further studies among people except for white participants and more accessible factors are necessary to explore.

Associations of the serum n-6 PUFA with exercise cardiac power in men

Low intake or tissue concentrations of the n-6 PUFA, especially to the major n-6 PUFA linoleic acid (LA), and low exercise cardiac power (ECP) are both associated with CVD risk. However, associations of the n-6 PUFA with ECP are unknown. The aim of the present study was to explore cross-sectional associations of the serum total n-6 PUFA, LA, arachidonic acid (AA), γ-linolenic acid (GLA) and dihomo-γ-linolenic acid (DGLA) concentrations with ECP and its components. In total, 1685 men aged 42-60 years from the Kuopio Ischaemic Heart Disease Risk Factor Study and free of CVD were included. ANCOVA was used to examine the mean values of ECP (maximal oxygen uptake (VO2max)/maximal systolic blood pressure (SBP)) and its components in quartiles of the serum total and individual n-6 PUFA concentrations. After multivariable adjustments, higher serum total n-6 PUFA concentration was associated with higher ECP and VO2max (for ECP, the extreme-quartile difference was 0·77 ml/mmHg (95 % CI 0·38, 1·16, Pfor trend across quartiles < 0·001) and for VO2max 157 ml/min (95 % CI 85, 230, Pfor trend < 0·001), but not with maximal SBP. Similar associations were observed with serum LA concentration. Higher serum AA concentration was associated with higher ECP but not with VO2max or maximal SBP. The minor serum n-6 PUFA GLA and DGLA were associated with higher maximal SBP during exercise test and DGLA also with higher VO2max but neither with ECP. In conclusion, especially LA concentration was associated with higher ECP. This may provide one mechanism for the cardioprotective properties of, especially, LA.

Exercise cardiac power and the risk of heart failure in men: A population-based follow-up study

BACKGROUND

Little is known about exercise cardiac power (ECP), defined as the ratio of directly measured maximal oxygen uptake with peak systolic blood pressure during exercise, on heart failure (HF) risk. We examined the association of ECP and the risk of HF.

METHODS

This was a population-based cohort study of 2351 men from eastern Finland. The average time to follow-up was 25 years. Participants participated at baseline in an exercise stress test. A total of 313 cases of HF occurred.

RESULTS

Men with low ECP (<9.84 mL/mmHg, the lowest quartile) had a 2.37-fold (95% confidence interval (95%CI): 1.68-3.35, p < 0.0001) hazards ratio of HF as compared with men with high ECP (>13.92 mL/mmHg, the highest quartile), after adjusting for age. Low ECP was associated with a 1.96-fold risk (95%CI: 1.38-2.78, p < 0.001) of HF after additional adjustment for conventional risk factors. After further adjustment for left ventricular hypertrophy, the results hardly changed (hazards ratio = 1.87, 95%CI: 1.31-2.66, p < 0.001). One SD increase in ECP (3.16 mL/mmHg) was associated with a decreased risk of HF by 28% (95%CI: 17%-37%).

CONCLUSION

ECP provides a noninvasive and easily available measure from cardiopulmonary exercise tests in predicting HF. However, ECP did not provide additional value over maximal oxygen uptake_.

The role of cardiorespiratory fitness on the risk of sudden cardiac death at the population level: A systematic review and meta-analysis of the available evidence

Cardiorespiratory fitness (CRF) has been widely studied as a powerful and independent predictor of all-cause and disease-specific mortality. Sudden cardiac death (SCD) is recognized as a significant cause of mortality among the general population, including the general population without previous symptoms of any coronary heart disease (CHD). Consequently, SCD is an important public health problem, which constitutes a clinical challenge. Thus, prevention of SCD by detecting early risk factors could be a useful tool, contributing to the American Heart Association's goal of decreasing the incidence of SCD at the population level. The identification of these risk factors for CVD would facilitate the large-scale screening of those participants at higher risk of SCD. This systematic review collects information about the role of CRF on the risk of SCD at the available evidence, and analyzes the long-term influence of CRF as a risk factor and independent predictor of SCD.

[Place of the exercise stress test at the sportsman]

Is the stress test still part of the useful examinations in the detection of risk heart disease in sports subjects? Should we continue to use it as a surveillance examination in coronary sports patients? Meta-analysis, considering a ST subshift of more than 1mm as a criterion for positivity, underline the low prevalence of abnormal examinations and a significant rate of false-positives. But for the diagnosis of coronary artery disease, it is mainly the evolution of the ST segment to effort or recovery and the occurrence of stress arrhythmias that detect true positivity. When coronary risk is more important (presence of risk factors, resumption of sport, intense and prolonged efforts), it seems lawful to recommend such a review on a regular basis among men over 40 years of age with two risk factors but Also among veterans taking up sport after a period of prolonged inactivity. For the asymptomatic coronary athlete the stress test remains at the centre of the final decision for the resumption of a sport in competition irrespective of the method of revascularization. Of course the stress test, even inevitable, remains flawed in the detection of coronary artery disease in the asymptomatic athlete. However, it provides additional information on the condition of being maximal, and attaching importance to arrhythmias, the tensional profile and the maximum power developed in addition to the ST segment's only study.

Exercise cardiac power and the risk of coronary heart disease and cardiovascular mortality in men

PURPOSE

The aim of this study was to examine the relationship of exercise cardiac power (ECP), defined as a ratio of directly measured maximal oxygen uptake with peak systolic blood pressure during exercise, with the risk of mortality from coronary heart diseases (CHD) and cardiovascular diseases (CVD).

DESIGN

Population-based cohort study with an average follow-up of 25 years from eastern Finland. About 2358 men at baseline participated in exercise stress test and 182 CHD and 302 CVD deaths occurred.

RESULTS

Men with low ECP (< 8.7 mL/mmHg, lowest quartile) had a 3.5-fold (95% CI 2.1-5.8, p < 0.0001) risk of CHD mortality as compared with men with high ECP (>16.4 mL/mmHg, highest quartile) after adjusting for age and examination year. Low ECP was associated with a 2.8-fold risk of CHD and 2.4-fold for CVD mortality after additional adjustment for conventional risk factors. After further adjustment for leisure time physical activity, the results hardly changed (HR 2.5, 95% CI 1.71-3.67, p < 0.001).

CONCLUSION

ECP provides non-invasive and easily available measure for the prediction of CHD and CVD mortality. One of the most potential explanation for the association between ECP and the risk of CHD and CVD mortality is an elevated afterload and peripheral resistance indicated by hypertension. Key messages Index of exercise cardiac power defined as the ratio of directly measured maximal oxygen uptake (VO_2max) with peak systolic blood pressure gives prognostic information in coronary heart disease (CHD) and CVD mortality risk stratification. ECP provides non-invasive and easily available measure for the prediction of CHD and CVD mortality. One of the most potential explanation for the association between ECP and the risk of CHD and CVD mortality is an elevated afterload and peripheral resistance indicated by hypertension.

Changes in cardiorespiratory fitness predict incident hypertension: A population-based long-term study

OBJECTIVES

We investigated whether long-term changes in cardiorespiratory fitness (CRF) predict the risk of incident hypertension, independent of risk factors, in initially normotensive men.

METHODS

This prospective study from the Kuopio Ischemic Heart Disease Study included 431 male participants without hypertension who underwent symptom-limited maximal cardiopulmonary exercise testing at baseline and during a second examination, 11-years later, who were re-evaluated for hypertension at 20-year follow-up. Changes in CRF (%) were calculated as the difference in directly measured maximal oxygen uptake (VO_2max ) between the baseline and second examination, and classified into decreasing tertiles as percentages. Hypertension was defined as systolic and/or diastolic blood pressure ≥140/90 mmHg or hypertension that required antihypertensive medication as diagnosed by a physician.

RESULTS

During a 10-year follow-up after the second examination, 165 men (38%) developed hypertension. Men who demonstrated the largest decline in CRF between evaluations (-62.1% to -20.2%) had a 4.33-fold (95% CI 2.32-8.07, P < .001) risk of incident hypertension compared to men with the smallest decrease or improvement in CRF (-8.8% to 82.0%), after adjusting for age, follow-up duration, alcohol consumption, cigarette smoking, serum low and high density lipoprotein cholesterol, body mass index, daily energy expenditure (kcal) via physical activity, glomerular filtration rate, and baseline systolic blood pressure and VO_2max .

CONCLUSIONS

The present findings indicate that more marked decreases in measured CRF over time are independently associated with the risk of incident hypertension in men, suggesting that CRF should be considered a causal risk factor to predict future hypertension.

Role of risk stratification and genetics in sudden cardiac death

Sudden cardiac death (SCD) is a major public health issue due to its increasing incidence in the general population and the difficulty in identifying high-risk individuals. Nearly 300 000 - 350 000 patients in the United States and 4-5 million patients in the world die annually from SCD. Coronary artery disease and advanced heart failure are the main etiology for SCD. Ischemia of any cause precipitates lethal arrhythmias, and ventricular tachycardia and ventricular fibrillation are the most common lethal arrhythmias precipitating SCD. Pulseless electrical activity, bradyarrhythmia, and electromechanical dissociation also result in SCD. Most SCDs occur outside of the hospital setting, so it is difficult to estimate the public burden, which results in overestimating the incidence of SCD. The insufficiency and limited predictive value of various indicators and criteria for SCD result in the increasing incidence. As a result, there is a need to develop better risk stratification criteria and find modifiable variables to decrease the incidence. Primary and secondary prevention and treatment of SCD need further research. This critical review is focused on the etiology, risk factors, prognostic factors, and importance of risk stratification of SCD.

The association of serum long-chainn-3 PUFA and hair mercury with exercise cardiac power in men

Long-chainn-3 PUFA from fish and exercise capacity are associated with CVD risk. Fish, especially large and old predatory fish, may contain Hg, which may attenuate the inverse association of long-chainn-3 PUFA with CVD. However, the associations of long-chainn-3 PUFA or Hg exposure with exercise capacity are not well known. We aimed to evaluate the associations of serum long-chainn-3 PUFA EPA, docosapentaenoic acid (DPA) and DHA and hair Hg with exercise cardiac power (ECP, a ratio of VO2max:maximal systolic blood pressure (SBP) during an exercise test), a measure for exercise capacity. For this, data from the population-based Kuopio Ischaemic Heart Disease Risk Factor Study were analysed cross-sectionally in order to determine the associations between serum long-chainn-3 PUFA, hair Hg and ECP in 1672 men without CVD, aged 42–60 years. After multivariate adjustments, serum total long-chainn-3 PUFA concentration was associated with higher ECP and VO2max(Ptrendacross quartiles=0·04 andPtrend=0·02, respectively), but not with maximal SBP (Ptrend=0·69). Associations were generally similar when EPA, DPA and DHA were evaluated individually. Hair Hg was not associated with ECP, VO2maxor maximal SBP. However, the associations of total long-chainn-3 PUFA (Pinteraction=0·03) and EPA (Pinteraction=0·02) with higher VO2maxwere stronger among men with lower hair Hg. Higher serum long-chainn-3 PUFA concentration, mainly a marker for fish consumption in this study population, was associated with higher ECP and VO2maxin middle-aged men from eastern Finland.