Age is an independent risk factor for left atrial dysfunction: results from an observational study

Reference Ranges and Physiologic Variations of Left E/e' Ratio in Healthy Adults: Clinical and Echocardiographic Correlates

Background:

Transthoracic Doppler echocardiographic examination is commonly performed to define the diastolic ventricular function since it is widely available, noninvasive, and inexpensive with respect to other diagnostic imaging modalities. However, data regarding age- and gender-matched reference values are scanty and sometimes conflicting. This study aims to explore the physiologic variations of left ventricular (LV) E/e' ratio as assessed in a large cohort of healthy adults and to investigate clinical and echocardiographic correlates.

Methods:

From June 2007 to February 2014, 1168 healthy Caucasian adults (mean age 45.1 ± 15.6 years) performed standard echocardiographic examination (transthoracic echocardiogram).

Results:

E/e' constantly increases across all the age classes (P < 0.0001, analyses of variance both for males and females) with a strong statistically significant linear positive correlation with age. Stepwise multiple linear regression analysis identified age (P < 0.0001), LV mass (P < 0.001), LV end-diastolic volume (P < 0.01), and left atrial volume (P < 0.001) as the only independent determinants of E/e' ratio (model R² = 0.54, P < 0.0001).

Conclusions:

In healthy subjects, transmitral E velocity to e' ratio changes in relation to the age: it increased with a statistically significant correlation in individuals older than 60 years. Hence, differences related to demographic and anthropometric measurements may potentially develop a misclassification of otherwise normal individuals when established on dichotomically suggested normal reference values. Our study can demonstrate that it is indispensable to apply specific cutoff related to the age and gender to properly assess LV diastolic function.

Morphological features of the left atrial appendage in consecutive coronary computed tomography angiography patients with and without atrial fibrillation

The majority of intracardiac thrombi form in the left atrial appendage (LAA). Enlargement of this structure, together with certain morphological features, may indicate a predisposition to the formation of thrombi and subsequent cardioembolic stroke. Thus far, studies on LAA morphology have largely focused on those patients with atrial fibrillation (AF). Taking a different approach, we investigated the variation in LAA morphology in a consecutive patient population with and without AF. We evaluated 808 consecutive patients (529 females; mean age 52.5±9.9 years) who underwent coronary artery computed tomography angiography (CCTA), the majority of whom (749) had no history of AF. We assessed the length, lobe number, and morphological classification of their LAAs. Demographic data and medical histories were collated from medical records and then correlated with LAA morphology. The proportions of each of the four morphological classes of LAA for the overall vs. non-AF population were: WindSock, 62.3/61.5%; Cactus, 18.6/18.8%; ChickenWing, 10.0/10.0%; and CauliFlower, 9.2/9.6%. Age (p<0.001; r = 0.156) and female gender (p<0.001) were both found to be associated with an increased body surface area (BSA)-related LAA length. Male patients were more likely to manifest multi-lobed (p = 0.003) LAAs, and overweight patients with a greater number of multi-lobed LAA morphological classes (p = 0.010). No associations with morphological LAA features could be found for patients with diabetes, hypertension, or dyslipidemia. Nor did the size of the left atrium exhibit any correlation with BSA-related LAA length. In the overall and non-AF populations, aging and female gender were associated with longer BSA-indexed LAAs.

Efficacy and safety of catheter ablation vs. rate control of atrial fibrillation in systolic left ventricular dysfunction : A meta-analysis and systematic review

PURPOSE

It is unclear what constitutes the optimal strategy for management of atrial fibrillation (AF) in patients with systolic left ventricular (LV) dysfunction. We hypothesized that catheter ablation of AF had benefits compared with rate control in patients with systolic LV dysfunction.

METHODS

PubMed, Embase, and the Cochrane Library were searched for randomized controlled trials and nonrandomized, observational studies. Weighted mean differences (WMD) and 95 % confidence intervals (CIs) were calculated to compare the improvement of left ventricular ejection fraction (LVEF), functional capacity, and quality of life between a catheter ablation group and a rate control group.

RESULTS

Six trials with 324 patients were included in the analysis. Patients in the catheter ablation group had greater improvement of LVEF (WMD: 8.89; 95 % CI: 6.93-10.86; p < 0.001), 6-min walk distance (WMD: 46.9; 95 % CI: 28.5-65.4; p < 0.001), and lower Minnesota Living With Heart Failure Questionnaire (MLHFQ) scores (WMD: - 19.6; 95 % CI: - 23.6-- 15.7; p < 0.001) compared with patients in the rate control group. Overall, there were only ten procedure-related events and the procedure-related events rate was 4.9 % per procedure and 5.6 % per patient.

CONCLUSION

The present analysis suggests that catheter ablation of AF has benefits in terms of an improvement in LVEF, in functional capacity, and in quality of life compared with rate control in patients with systolic LV dysfunction, and the risk of complications related to procedures is acceptable.

Age is an independent risk factor for left atrial dysfunction: results from an observational study

Introduction. The degenerative changes of myocardial tissue are thought to influence left atrial (LA) function. Changes of left atrial function are generally due to changes in left ventricle (LV) compliance. But valvular dysfunction and hypertension as comorbidity cannot be ignored. Women have a different clinical profile compared with men concerning the risk of heart failure. We investigated the influence of increasing age and gender corrected for comorbidity, on left atrial function.Methods. Using an open access echocardiography database, supplemented with additional LA function measurements, we defined three different LA function parameters. Odds ratios (OR) were calculated to reproduce the relation between age, gender and LA function. The association between age, gender and LA function was estimated, and corrected for comorbid conditions as valve disease, high blood pressure and LV dysfunction, using logistic regression.Results. Higher age was positively correlated with increased LA volume, decreased ejection fraction and increased LA kinetic energy. Age per decade increase, corrected for comorbidity, resulted in an increased risk of LA dysfunction (OR between 1.5 and 1.9). Gender had little influence on LA function parameters except for LA maximal volume. Men had a significantly larger LA maximal volume compared with women. Conclusions. In this open access echocardiography database, increasing age was correlated with LA dysfunction. Age per decade increase, corrected for comorbid conditions such as mitral and aortic valve disease, hypertension and heart failure, is an independent risk factor for LA dysfunction. The gender influence on LA dysfunction seems to be limited. (Neth Heart J 2010;18:243-7.).

Acute effects of adrenergic agents on post-defibrillation arrest time in a cultured heart model

Possible drug interactions with electrical defibrillation were examined. We tested the hypothesis that adrenergic agents (epinephrine, norepinephrine, isoproterenol) and a calcium channel blocker (verapamil), when applied acutely, alter the duration of arrest following a defibrillator shock. A secondary hypothesis (based on observations) was that the drugs alter the occurrence of changes to normal rhythms following the shock. Dissociated heart cells from 10-day chicken embryos were cultured to form spherical aggregates and plated in petri dishes. In the experiments, the spheres were paced at 0.75 V/cm above contraction threshold, and a biphasic defibrillator shock was applied for 1 ms at 46 V/cm. The arrest time and occurrence of rhythm changes were recorded. The adrenergic agents shortened the duration of arrest following a defibrillator shock, while the calcium channel blocker lengthened the arrest time. Comparisons with the control proportion of double beats showed no significant change with the adrenergic agents and a decrease with verapamil.