Left atrial volume index is critical for the diagnosis of heart failure with preserved ejection fraction :

Approximately 50% of patients with heart failure have a left ventricular ejection fraction of at least 45%, but no therapies have been shown to improve the outcome of these patients. Therefore, we studied the effects of irbesartan in patients with this syndrome. We enrolled 4128 patients who were at least 60 years of age and had New York Heart Association class II, III, or IV heart failure and an ejection fraction of at least 45% and randomly assigned them to receive 300 mg of irbesartan or placebo per day. The primary composite outcome was death from any cause or hospitalization for a cardiovascular cause (heart failure, myocardial infarction, unstable angina, arrhythmia, or stroke). Secondary outcomes included death from heart failure or hospitalization for heart failure, death from any cause and from cardiovascular causes, and quality of life. During a mean follow-up of 49.5 months, the primary outcome occurred in 742 patients in the irbesartan group and 763 in the placebo group. Primary event rates in the irbesartan and placebo groups were 100.4 and 105.4 per 1000 patient-years, respectively (hazard ratio, 0.95; 95% confidence interval [CI], 0.86 to 1.05; P=0.35). Overall rates of death were 52.6 and 52.3 per 1000 patient-years, respectively (hazard ratio, 1.00; 95% CI, 0.88 to 1.14; P=0.98). Rates of hospitalization for cardiovascular causes that contributed to the primary outcome were 70.6 and 74.3 per 1000 patient-years, respectively (hazard ratio, 0.95; 95% CI, 0.85 to 1.08; P=0.44). There were no significant differences in the other prespecified outcomes. Irbesartan did not improve the outcomes of patients with heart failure and a preserved left ventricular ejection fraction. (ClinicalTrials.gov number, NCT00095238.) 2008 Massachusetts Medical Society

Left ventricular (LV) diastolic dysfunction is prevalent in the community. Current assessment of diastolic function can be complex, involving Doppler evaluation of an array of hemodynamic data. The relation between left atrial (LA) volume and diastolic function, and between LA volume and cardiovascular risk and disease burden are not well known. In the present prospective study of 140 adults, mean age 58 +/- 19 years, referred for a clinically-indicated echocardiogram and in sinus rhythm, with no history of atrial arrhythmias or valvular heart disease, we determined the LA volume, LV diastolic function status, cardiovascular risk score (based on age, gender, history of systemic hypertension, diabetes mellitus, hyperlipidemia, and smoking), and cardiovascular disease burden (based on confirmed vascular disease, congestive heart failure, and transient ischemic attack or stroke). LA volume was found to correlate positively with age, body surface area, cardiovascular risk score, LV end-diastolic and end-systolic dimensions, LV mass, diastolic function grade, tissue Doppler E/E', tricuspid regurgitation velocity, and negatively with LV ejection fraction (all p <0.006). In a multivariate clinical model, LA volume indexed to body surface area (indexed LA volume) was independently associated with cardiovascular risk score (p <0.001), congestive heart failure (p = 0.014), vascular disease (p = 0.012), transient ischemic attack or stroke (p = 0.021), and history of smoking (p = 0.008). In a clinical and echocardiographic model, indexed LA volume was strongly associated with diastolic function grade (p <0.001), independent of LV ejection fraction, age, gender, and cardiovascular risk score. In patients without a history of atrial arrhythmias or valvular heart disease, LA volume expressed the severity of diastolic dysfunction and provided an index of cardiovascular risk and disease burden.

We examined the association between diastolic function and left atrial volume indexed to body surface area (LAVi) in a population-based study. Atrial enlargement has been suggested as a marker of the severity and duration of diastolic dysfunction (DD). However, the association between DD and atrial enlargement and their individual prognostic implications in the population is poorly defined. A cross-sectional sample of Olmsted County, Minnesota, residents > or =45 years of age (n=2,042) underwent comprehensive Doppler echocardiography and medical record review. The LAVi increased with worsening DD: 23 +/- 6 ml/m2 (normal), 25 +/- 8 ml/m2 (grade I DD), 31 +/- 8 ml/m2 (grade II DD), 48 +/- 12 ml/m2 (grades III to IV DD). In bivariate analyses, age, left ventricular mass index, and DD grade were positively associated, whereas female gender and ejection fraction (EF) were inversely associated with LAVi (p <0.001 for all). When controlling for age, gender, cardiovascular (CV) disease, EF, and left ventricular mass, grade II DD was associated with a 24%, and grade III to IV DD was associated with a 62% larger LA volume (p <0.0001 for both). The area under the receiver-operator characteristic curve for LAVi to detect grade I, grade II, or grade III to IV DD was 0.57, 0.81, and 0.98, respectively. Both DD and LAVi were predictive of all-cause mortality, but when controlling for DD, LAVi was not an independent predictor of mortality. These data suggest that DD contributes to LA remodeling. Indeed, DD is a stronger predictor of mortality; presumably it better reflects the impact of CV disease within the general population.