Left atrial strain is associated with long-term mortality in acute coronary syndrome patients.

To investigate the long-term prognostic value of the left atrial (LA) strain indices - peak atrial longitudinal strain (PALS), peak conduit strain (PCS), and peak atrial contractile strain (PACS) in acute coronary syndrome (ACS) patients in relation to all-cause mortality. This retrospective study included ACS patients treated with percutaneous coronary intervention (PCI) and examined with echocardiography. Exclusion criteria were non-sinus rhythm during echocardiography, missing images, and inadequate image quality for 2D speckle tracking analysis of the LA. The endpoint was all-cause death. Multivariable Cox regression which included relevant clinical and echocardiographic measures was utilized to assess the relationship between LA strain parameters and all-cause mortality. A total of 371 were included. Mean age was 64 years and 76% were male. Median time to echocardiography was 2 days following PCI. During a median follow-up of 5.7 years, 83 (22.4%) patients died. Following multivariable analysis, PALS (HR 1.04, 1.01-1.06, p = 0.002, per 1% decrease) and PCS (HR 1.05, 1.01-1.09, p = 0.006, per 1% decrease) remained significantly associated with all-cause mortality. PALS and PCS showed a linear relationship with the outcome whereas PACS was associated with the outcome in a non-linear fashion such that the risk of death increased when PACS < 18.22%. All LA strain parameters remained associated with worse survival rate when restricting analysis to patients with left atrial volume index < 34 ml/m2. Reduced LA function as assessed by PALS, PCS, and PACS were associated with an increased risk of long-term mortality in patients with ACS.

Echocardiographic Measures of Left Atrial Structure and Function and the Association with Atrial Fibrillation following Acute Coronary Syndrome.

INTRODUCTION: Acute coronary syndrome (ACS) is associated with an increased risk of developing atrial fibrillation (AF). This arrhythmia is associated with adverse outcomes, making it important to identify high-risk patients. The aim was to evaluate the prognostic value of measures of left atrial (LA) structure and function in AF prediction following ACS. METHODS: Three hundred and eighty-one patients who had a percutaneous coronary intervention for ACS were included in the study. Our endpoint was new-onset AF. RESULTS: With a median follow-up time of 5.4 [3.9-6.8] years, 56 patients (14.7%) developed AF. Patients developing AF had significantly (p ≤ 0.05) increased maximal and minimal LA volumes (LAVmax and LAVmin, respectively). LAVmax and LAVmin remained significantly increased in AF patients when indexing to either body surface area (LAVmax/BSA and LAVmin/BSA, respectively), left ventricle length in end diastole (LAVmax/LVLd and LAVmin/LVLd, respectively), or late mitral annular diastolic velocity (LAVmax/a' and LAVmin/a', respectively), while LA expansion index (LAEi), LA emptying fraction (LAEF), and peak LA longitudinal strain (PALS) were decreased. In univariable Cox regressions, all LA measures were found to be predictors of AF. After multivariable adjustment for clinical and echocardiographic parameters, all measures reflecting atrial function (LAVmin, LAVmin/BSA, LAVmin/LVLd, LAVmin/a', LAVmax/a', LAEF, LAEi, and PALS) (p ≤ 0.05) but no structural measures (LAVmax, LAVmax/BSA, and LAVmax/LVLd) remained significant independent predictors of AF. CONCLUSION: Echocardiographic measures of LA function are independent predictors of AF following ACS. Evaluation of LA function might improve the prognostic workup, aid in risk stratification for AF, and improve selection for further examinations.