Association Between ECG Abnormalities and Mortality in a Low-Risk Population

BACKGROUND

The ECG is a simple, noninvasive screening method for cardiovascular disease and arrhythmia. The impact of ECG abnormality on mortality is not certain in low-risk populations. To address this, we evaluated the association between ECG abnormality and mortality.

METHODS AND RESULTS

We retrospectively assessed baseline ECG and all-cause mortality and cardiovascular mortality in 660 383 patients presenting for medical check-ups. Baseline ECG abnormalities were classified according to the Minnesota Code. Among the total 660 383 participants, 23 609 (3.6%) had major and 110 038 (16.7%) had minor ECG abnormalities. All-cause mortality occurred in 7751 patients (1.1%) and cardiovascular mortality in 1180 (0.18%) over a median follow-up period of 8.8 years. Major ECG abnormalities were associated with all-cause mortality (hazard ratio [HR], 1.11 [95%, 1.03-1.2]) and cardiovascular mortality (HR, 1.92 [95% CI, 1.63-2.27]) compared with no ECG abnormalities. All-cause mortality was associated with right atrial enlargement (HR, 2.11 [95% CI, 1.1-4.07]), left atrial enlargement (HR, 1.76 [95% CI, 1.1-2.84]), sinus tachycardia (HR, 1.52 [95% CI, 1.15-2.01]), complete atrioventricular block (HR, 2.1 [95% CI, 1.05-4.2]), atrial fibrillation (HR, 1.52 [95% CI, 1.26-1.84]), and left ventricular hypertrophy (HR, 1.15 [95% CI, 1.02-1.3]). Cardiovascular mortality was associated with left atrial enlargement (HR, 4.52 [95% CI, 2.15-9.5]), atrial fibrillation (HR, 3.22 [95% CI, 2.33-4.46]), left ventricular hypertrophy (HR, 1.72 [95% CI, 1.35-2.19]), major Q-wave abnormality (HR, 1.6 [95% CI, 1.08-2.39]), and major ST-T abnormality (HR, 1.76 [95% CI, 1.01-3.04]).

CONCLUSIONS

ECG abnormalities, including left atrial enlargement, left ventricular hypertrophy, atrial fibrillation, and major Q-wave and ST-T abnormalities, were associated with cardiovascular mortality in a low-risk population.

Genetic support of a causal relationship between iron status and atrial fibrillation: a Mendelian randomization study

Background

Atrial fibrillation is the most common arrhythmia disease. Animal and observational studies have found a link between iron status and atrial fibrillation. However, the causal relationship between iron status and AF remains unclear. The purpose of this investigation was to use Mendelian randomization (MR) analysis, which has been widely applied to estimate the causal effect, to reveal whether systemic iron status was causally related to atrial fibrillation.

Methods

Single nucleotide polymorphisms (SNPs) strongly associated (P < 5 × 10−8) with four biomarkers of systemic iron status were obtained from a genome-wide association study involving 48,972 subjects conducted by the Genetics of Iron Status consortium. Summary-level data for the genetic associations with atrial fibrillation were acquired from the AFGen (Atrial Fibrillation Genetics) consortium study (including 65,446 atrial fibrillation cases and 522,744 controls). We used a two-sample MR analysis to obtain a causal estimate and further verified credibility through sensitivity analysis.

Results

Genetically instrumented serum iron [OR 1.09; 95% confidence interval (CI) 1.02–1.16; p = 0.01], ferritin [OR 1.16; 95% CI 1.02–1.33; p = 0.02], and transferrin saturation [OR 1.05; 95% CI 1.01–1.11; p = 0.01] had positive effects on atrial fibrillation. Genetically instrumented transferrin levels [OR 0.90; 95% CI 0.86–0.97; p = 0.006] were inversely correlated with atrial fibrillation.

Conclusion

In conclusion, our results strongly elucidated a causal link between genetically determined higher iron status and increased risk of atrial fibrillation. This provided new ideas for the clinical prevention and treatment of atrial fibrillation.

Longitudinal Associations Between Cumulative Physical Activity and Change in Structure and Function of the Left Side of the Heart: The Tromsø Study 2007–2016

Background

Current knowledge about the relationship between physical activity (PA) and cardiac remodeling is mainly derived from cross-sectional studies of athletes, and there is a knowledge gap of this association in the general adult and elderly population. Therefore, we aimed to explore the longitudinal association between cumulative PA and change in cardiac structure and function in a general adult and elderly population.

Methods

This longitudinal study includes 594 participants from the sixth (Tromsø6, 2007–08) and seventh (Tromsø7, 2015–16) survey of the Tromsø Study. Cardiac structure and function were assessed by echocardiography at two time points, and PA was self-reported by questionnaire at both time points. PA volume was expressed as cumulative PA (Low, Moderate, and Hard) and the association with left atrial (LA) and left ventricular (LV) structure and function was assessed using ANCOVA.

Results

Overall, LA diameter index (LADi) increased significantly more in Hard compared to Moderate PA (+0.08 cm/m², 95% CI 0.01–0.15, p = 0.020) from Tromsø6 to Tromsø7. When stratified by sex or age, higher levels of cumulative PA were associated with increased LADi in males and in participants <65 years only. Indexed LV mass (LVMi) increased significantly more in Moderate than in Low PA (+3.9 g/m^2.7, 95% CI 0.23–7.57, p = 0.037). When stratified by sex or age, these changes in LVMi and indexed LV diameter (LVDi) were only significant in females. No significant associations were observed between cumulative PA and change in relative wall thickness, E/e' ratio, e' velocity, LV ejection fraction, and LADi/LVDi ratio.

Conclusion

Higher levels of cumulative PA were associated with increased LADi in males and participants <65 years, and with increased LVMi and LVDi in females. Despite cardiac chamber enlargement, the pump function of the heart did not change with higher levels of PA, and the atrioventricular ratio was unchanged. Our results indicate that cardiac chamber enlargement is a physiological response to PA.

Efficacy and safety of dronedarone versus placebo in patients with atrial fibrillation stratified according to renal function: Post hoc analyses of the EURIDIS-ADONIS trials

BACKGROUND

The use of antiarrhythmic drugs (AADs) in patients with chronic kidney disease (CKD) is complex because impaired renal clearance can cause increased drug levels, and risk of intolerance or adverse events. Due to the propensity for CKD to occur alongside atrial fibrillation/atrial flutter (AF/AFL), it is essential that AAD safety and efficacy are assessed for patients with CKD.

HYPOTHESIS

Dronedarone, an approved AAD, may present a suitable therapeutic option for patients with AF/AFL and concomitant CKD.

METHODS

EURIDIS-ADONIS (EURIDIS, NCT00259428; ADONIS, NCT00259376) were identically designed, multicenter, double-blind, parallel-group trials investigating AF/AFL control with dronedarone 400 mg twice daily versus placebo (randomized 2:1). In this post hoc analysis, the primary endpoint was time to first AF/AFL. Patients were stratified according to renal function using the CKD-Epidemiology Collaboration equation and divided into estimated glomerular filtration rate (eGFR) subgroups of 30-44, 45-59, 60-89, and ≥90 ml/min. Time-to-events between treatment groups were compared using log-rank testing and Cox regression.

RESULTS

At baseline, most (86%) patients demonstrated a mild or mild-to-moderate eGFR decrease. Median time to first AF/AFL recurrence was significantly longer with dronedarone versus placebo for all eGFR subgroups except the 30 to 44 ml/min group, where the trend was similar but statistical power may have been limited by the small population. eGFR stratification had no significant effect on serious adverse events, deaths, or treatment discontinuations.

CONCLUSIONS

This analysis suggests that dronedarone could be an effective therapeutic option for AF with an acceptable safety profile in patients with impaired renal function.

Echocardiographic assessment of diastolic dysfunction in elderly patients with severe aortic stenosis before and after aortic valve replacement

Background

The 2016 guidelines of the American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging (EACVI) for evaluation of left ventricular (LV) diastolic dysfunction by Doppler flow and tissue Doppler- echocardiography do not adjust assessment of high filling pressures for patients with aortic stenosis (AS). However, most of the studies on this patient group indicate age independent specific diastolic features in AS. The aim of this study is to identify disease-specific range and distribution of diastolic functional parameters and their ability to identify high N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels as a marker for high filling pressures.

Methods

In this study, 169 patients who underwent surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) were prospectively enrolled. Resting echocardiography was performed including Doppler of the mitral inflow, pulmonary venous flow, tricuspid regurgitant flow and tissue Doppler in the mitral ring and indexed volume-estimates of the left atrium (LAVI). Echocardiography, and NT-proBNP levels were assessed before TAVR/SAVR and at two postoperative visits at 6 and 12 months.

Results

Pre- and postoperative values were septal e′; 5.1 ± 3.9, 5.2 ± 1.6 cm/s; lateral e′ 6.3 ± 2.1; 7.7 ± 2.7 cm/s; E/e′19 ± 8; 16 ± 7 cm/s; E velocity 96 ± 32; 95 ± 32 cm/s; LAVI 39 ± 8; 36 ± 8 ml/m², pulmonary artery pressure (PAP) 39 ± 8; 36 ± 8 mmHg, respectively. The scoring recommended by ASE/EACVI detected elevated NT pro-BNP with a specificity of 25%. Adjusting thresholds towards PAP ≥ 40 mmHg, E velocity ≥ 100 cm/s, E deceleration time < 220 ms, and E/septal e′ ≥ 20 or septal e′ < 5.0 cm/s increased prediction of NT-proBNP levels ≥500 ng/L with substantially improved specificity (> 85%).

Conclusion

Diastolic echocardiographic parameters in AS indicate persistent impaired relaxation and NT-proBNP indicate elevated filling pressures in most of the patients, improving only modestly 6–12 months after TAVR and SAVR. Applying the 2016 ASE/EACVI recommendations for detection of elevated filling pressures to patients with AS, elevated NT pro-BNP levels could not be reliably detected. However, adjusting thresholds of the echocardiographic parameters increased specificities to useful diagnostic levels.

Trial registration

The study was prospectively approved by the regional ethical committee, REK North with the registration number: REK 2010/397-10.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12947-021-00262-1.

Prognostic Significance of Echocardiographic Measures of Cardiac Remodeling in the Community

PURPOSE OF REVIEW

Echocardiography is a noninvasive tool of choice for evaluating cardiac structure and function in numerous cardiac conditions ranging from congenital heart disease, myocardial diseases, coronary artery disease (CAD), valvulopathies, arrhythmias, and pericardial disorders. We review the prognostic significance of echocardiographic indices of cardiac remodeling in the general population.

RECENT FINDINGS

Recent meta-analyses have confirmed the prognostic significance of echocardiographic measurements (left ventricular mass/hypertrophy, systolic and diastolic dysfunction, left atrial dimensions and function, and strain rate measures) in asymptomatic people in the community for adverse clinical outcomes including CAD, stroke, heart failure, atrial fibrillation, sudden death, and all-cause mortality. The clinical utility of screening echocardiography has been examined comprehensively in hypertensive patients, where it is challenged by measurement variability. Echocardiographic measures predict cardiovascular disease outcomes consistently in multiple community-based epidemiological studies. However, the clinical utility of screening asymptomatic individuals with echocardiography in population-based settings is limited.

Cross-sectional associations between accelerometry-measured physical activity, left atrial size, and indices of left ventricular diastolic dysfunction: The Tromsø Study

Whereas left atrial (LA) enlargement is an independent predictor for adverse cardiovascular events and all-cause mortality, this is regarded a physiological adaption of exercise. Paradoxically, LA size in athletes may overlap the enlargement observed in patients with cardiac pathology. Current knowledge is mainly derived from studies of athletes, and little is known about cardiac adaptations to physical activity (PA) in the general population. We explored the association between objectively measured PA and LA volume index (LAVi), and between LAVi enlargement and indices of diastolic dysfunction stratified by PA-level. Our study included 1573 participants from the population-based Tromsø Study (2015-16). PA was assessed with an ActiGraph wGT3X-BT accelerometer. Echocardiography was performed according to current guidelines. The associations between PA and LAVi, and between LAVi enlargement and indices of diastolic dysfunction were estimated by univariable and multivariable linear regression analyses, adjusted for sex, age, and cardiovascular risk factors. Our multiple adjusted analyses showed significant linear associations between PA and LAVi in ages < 70 years, and between PA and LAVi in participants with normal diastolic function. No associations were seen in ages ≥ 70 years or for participants with abnormal diastolic function. In those 40-54 years, the most active participants had larger LAVi (4.45 mL/m2, p = 0.016) than the least active. LAVi enlargement was only associated with indices of diastolic dysfunction in the most inactive participants. In conclusion, higher levels of PA associate with greater LAVi in participants < 70 years with normal diastolic function. LAVi enlargement is only associated with diastolic dysfunction in the most inactive participants.

Echocardiographic Changes with Positive Airway Pressure Therapy in Obesity Hypoventilation Syndrome. Long-Term Pickwick Randomized Controlled Clinical Trial

Rationale: Obesity hypoventilation syndrome (OHS) has been associated with cardiac dysfunction. However, randomized trials assessing the impact of long-term noninvasive ventilation (NIV) or continuous positive airway pressure (CPAP) on cardiac structure and function assessed by echocardiography are lacking.Objectives: In a prespecified secondary analysis of the largest multicenter randomized controlled trial of OHS (Pickwick Project; N = 221 patients with OHS and coexistent severe obstructive sleep apnea), we compared the effectiveness of three years of NIV and CPAP on structural and functional echocardiographic changes.Methods: At baseline and annually during three sequential years, patients underwent transthoracic two-dimensional and Doppler echocardiography. Echocardiographers at each site were blinded to the treatment allocation. Statistical analysis was performed using a linear mixed-effects model with a treatment group and repeated measures interaction to determine the differential effect between CPAP and NIV.Measurements and Main Results: A total of 196 patients were analyzed: 102 were treated with CPAP and 94 were treated with NIV. Systolic pulmonary artery pressure decreased from 40.5 ± 1.47 mm Hg at baseline to 35.3 ± 1.33 mm Hg at three years with CPAP, and from 41.5 ± 1.56 mm Hg to 35.5 ± 1.42 with NIV (P < 0.0001 for longitudinal intragroup changes for both treatment arms). However, there were no significant differences between groups. NIV and CPAP therapies similarly improved left ventricular diastolic dysfunction and reduced left atrial diameter. Both NIV and CPAP improved respiratory function and dyspnea.Conclusions: In patients with OHS who have concomitant severe obstructive sleep apnea, long-term treatment with NIV and CPAP led to similar degrees of improvement in pulmonary hypertension and left ventricular diastolic dysfunction.Clinical trial registered with www.clinicaltrials.gov (NCT01405976).

Higher Mortality in Case of Small Left Atrium on Nongated Computed Tomography Pulmonary Angiography Is Associated With the Presence of Malignancy

PURPOSE

The purpose of this study was to evaluate the association between small left atria (LA) according to computed tomography pulmonary angiography (CTPA) and mortality among individuals without pulmonary embolism, and to examine which volumes begin to portend adverse outcomes.

MATERIALS AND METHODS

Left atrial volume indices (LAVIs) of 752 consecutive patients who underwent CTPA, in which pulmonary embolism were ruled out, were measured retrospectively using an automatic 4-chamber volumetric analysis software. Groups of 5 percentiles within the lower quartile were investigated, and the interquartile range (25th to 75th percentiles) was regarded as the control group.

RESULTS

Patients within the lower 25th LAVI percentiles (<33 mL/m2; n=188) were younger and had less cardiovascular morbidities, while malignancies were less common in the control group (LAVI: 33 to 54 mL/m2; n=376). Percentiles 5th to 25th did not demonstrate an independent association with mortality. After adjustment for baseline characteristics, the risk for 30-day and 1-year mortality was 5.6 (95% confidence interval: 2.1-14.8, P=0.001) and 6.1 (95% confidence interval: 2.4-15.1, P<0.001) times higher, respectively, among the lowest five LAVI percentiles (<24 mL/m2) compared with the control group. Among patients with small LA who died within 1 year, 83% had a diagnosis of malignancy. Albeit, only a minority (3%) of patients with malignancies had small LA.

CONCLUSIONS

Individuals undergoing CTPA whose LAVI is within the lowest five percentiles have a markedly increased risk for short-term and long-term mortality. The risk can probably be attributed to an underlying malignancy. The feasibility of 4-chamber volumetric analysis while avoiding a time-consuming process due to the automatic properties enables the introduction of this feature to clinical practice.