Prognostic utility of routine assessment of left ventricular global longitudinal strain and peak atrial reservoir strain in stable heart disease patients

Abstract

Abstract Background Left ventricular ejection fraction above 40% is a poor predictor of cardiac outcomes. Strain imaging seems to add incremental prognostic value in various heart conditions. Purpose The aim of the study is to investigate whether assessment of both left ventricular global longitudinal strain (LVGLS) and peak atrial reservoir strain (PARS) in routine daily practice is useful in predicting cardiac events. Methods We prospectively enrolled 300 patients (212 men, mean age 64.8±10.9 years old) with stable cardiac disease, referred for echocardiographic examination and eligible for strain imaging. Conventional and speckle tracking 2D rest echocardiography were performed and clinical variables were recorded. We excluded patients with acute coronary syndromes, severe valvular disease, cardiomyopathies, arrhythmia and class IV NYHA. Results During a median follow up of 30 months, there were 111 cardiac events (CE) recorded including: 7 cardiac deaths (CD), 25 acute coronary syndromes (ACS), 45 hospitalisations for worsening heart failure (WHF), 23 episodes of atrial fibrillation (AF), 11 stroke (S). Average EF, LVGLS and PARS in patients with CE were significantly lower than in patients without CE (55.8±8.4%, −17.3±3.9% and 16.3±9.8% vs. 60.4±8.4%, −20.1±3.7% and 28.4±8.2%; p<0.05, p<0.01, p<0.01). In univariate analysis, lower LVGLS, respectively lower PARS were associated with a higher risk of cardiac events [Hazard Ratio (HR)1.26; 95% CI (confidence interval): 1.08–1.34; p<0.01 per 1% decrease, respectively HR 1.38; 95% CI: 1.16–1.42; p<0.01 per 1% decrease]. On multivariate analysis this association was independent after adjustment for age, gender, hypertension, diabetes, ejection fraction, left atrial indexed volume. Lower LVGLS was a better predictor of a composite of ACS and CD (HR 1.38 per 1% decrease 95% CI: 1.16–1.48; p<0.01). Lower PARS had a stronger association with AF, S and WHF (HR 1.49 per 1% decrease 95% CI: 1.19–1.58; p<0.01). In a model defined by depressed LVGLS (more positive than −18%) adding lower PALS, with a cut off point of 20%, significantly improved prediction of CE (C-statistic increased from 0.68 to 0.83, p<0.001). Conclusions Left ventricular global longitudinal strain and peak atrial reservoir strain are independent predictors of cardiac events patients with stable heart disease. Acute coronary syndromes and death were better predicted by depressed LVGLS and onset of atrial fibrillation, stroke and worsening heart failure were better predicted by lower PARS. Routine assessment of both parameters improves significantly prediction of cardiac events and helps clinical decision making. Funding Acknowledgement Type of funding source: None