Introduction: Left ventricular systolic function is an important marker of diagnosis and prognosis of pati-ents with cardiovascular disease.
Objective: To assess the usefulness of routine evalua-tion of left ventricular global longitudinal strain of the (GLS) in the characterization of the systolic function in relation with the ejection fraction calculated by 2d echocardiography, Simpson method.
Methods: The study included 175 consecutive patients with previously diagnosed stable cardiac disease. The systolic and diastolic function of the left ventricle was evaluated by conventional two-dimensional rest echo-cardiography and Doppler method. The ejection VS fraction was calculated by Simpson method and GLS was measured with two-dimensional speckle tracking rest echocardiography in apical 2, 3 and 4 chambers, after visual verification and manual adjustment of the tracking.
Results: 202 consecutive patients were evaluated by 2D rest echocardiography of which 27 patients (12.8%) were excluded because of inaproppriate acoustic win-dow for speckle tracking. There were included 175 pa-tients average age 63.9±10.4 years old, 68% men. Ave-rage LVEF and GLS in the evaluated group was 52±8% and-18.7±3.7%, respectively. The correlation between the two parameters was statistically significant (r=- 0.7, p<0.001). The analysis of subgroups corresponding to LVEF values demonstrates also a statistically signi-ficant different average GLS, respectively, at EF <40% the average value of GLS was – 9.2±2.7, between 40% and 49% GLS was -14.9±2, between 50% and 54% GLS was -16.2±2.3 and at EF ≥55%, averrage GLS was -20.5±4.5 (p<0,05). Analysis of the correlation between LVEF and GLS within each subgroup showed that for the subgroup with FE ≥55% there is a week correlation (r=-0.5, p=0.05) but in the other subgroups is absent, suggesting that the severity of left ventricular systolic dysfunction could be different at equal LVEF.
Conclusions: Stratification of GLS values in relation with LVEF is providing additional information regarding left ventricular systolic function. In patients with EF ≥55% values of GLS less negative than -20%, identi-fies subtle left ventricular systolic dysfunction . Patients with a borderline EF (between 50% and 54%) represent a distinct subset with systolic left ventricular dysfuncti-on expressed by mean values of GLS less negative than -17%. Patients with intermediate or low LVEF values of GLS higher than that may represent markers reserved prognosis. The mentioned GLS threshold values may influence therapeutic decisions in clinical practice.