Prognostic power of global 2D strain according to left ventricular ejection fraction in patients with ST elevation myocardial infarction

Global longitudinal strain in long-term risk prediction after acute coronary syndrome: an investigation of added prognostic value to ejection fraction

AIMS

This study aimed to investigate the additional value of global longitudinal strain (GLS) on top of left ventricular ejection fraction (LVEF) in long-term risk prediction of combined death and heart failure (HF) re-hospitalization after acute coronary syndrome (ACS).

METHOD AND RESULTS

This retrospective study included patients admitted with ACS between 2008 and 2014 from the three participating university hospitals. LVEF and GLS were assessed at a core lab from images acquired during the index hospital stay. Their prognostic value was studied with the Cox proportional hazards model (median follow-up 6.2 years). A nested model comparison was performed with C-statistics. A total of 941 patients qualified for multivariable analysis after multiple imputation of missing baseline covariables. The combined outcome was reached in 17.7% of the cases. Both GLS and LVEF were independent predictors of the combined outcome, hazard ratio (HR) 1.068 (95% CI 1.017-1.121) and HR 0.980 (95% CI 0.962-0.998), respectively. The C-statistic increased from 0.742 (95% CI 0.702-0.783) to 0.749 (95% CI 0.709-0.789) (P = 0.693) when GLS entered the model with clinical data and LVEF.

CONCLUSION

GLS emerged as an independent long-term risk predictor of all-cause death and HF re-hospitalization. However, there was no significant incremental predictive value of GLS when LVEF was already known.

Prognostic implications of left ventricular myocardial work index in patients with ST-segment elevation myocardial infarction and reduced left ventricular ejection fraction

AIMS

This study aimed to determine whether lower values of left ventricular (LV) global work index (GWI) at baseline were associated with a reduction in LV functional recovery and poorer long-term prognosis in patients with reduced LV ejection fraction (LVEF ≤40%) following ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 197 individuals (62 ± 12 years, 75% male) with STEMI treated with primary percutaneous coronary intervention and reduced LVEF were evaluated. All patients were followed up for the occurrence of all-cause mortality and the presence of LVEF normalization at 6 months (LVEF ≥50%). The median LVEF was 36% (interquartile range 32-38) and the mean value of LV GWI was 1041 ± 404 mmHg% at baseline. At 6-month follow-up, 41% of patients had normalized LVEF. On multivariable logistic regression, higher values of LV GWI were independently associated with LVEF normalization at 6 months of follow-up (odds ratio 1.32 per 250 mmHg%, P = 0.038). Over a median follow-up of 112 months, 40 patients (20%) died. LV GWI <750 mmHg% was independently associated with all-cause mortality (HR 3.85, P < 0.001) and was incremental to LV global longitudinal strain (P = 0.039) and LVEF (P < 0.001).

CONCLUSION

In individuals with an LVEF ≤40% following STEMI, higher values of LV GWI were associated with a greater probability of LVEF normalization at 6-month follow-up. In addition, lower values of LV GWI were independently associated with increased all-cause mortality at long-term follow-up, providing incremental prognostic value over LVEF and minor incremental prognostic value over LV global longitudinal strain.

Speckle Tracking Stress Echocardiography on Treadmill in Assessment of the Functional Significance of the Degree of Coronary Artery Disease

Aim        To determine diagnostic capabilities of left ventricular (LV) global longitudinal systolic strain (GLSS) in stress echocardiography (stress-EchoCG) with a treadmill test for diagnosing the functional significance of the degree of coronary stenosis.Material and methods        The study included 121 patients (73 men aged 68.3±7.7 years) with suspected or previously diagnosed ischemic heart disease (IHD). Speckle-tracking stress-EchCG (method of tracking speckles on two-dimensional gray-scale ultrasonic images) with a treadmill test and coronarography was performed for all patients. The patients were divided into 3 groups based on the severity of coronary artery (CA) stenosis according to the Gensini scale.Results   LV GLSS at rest did not significantly differ between the study groups. After the exercise, LV GLSS was significantly lower in patients with pronounced CA stenosis than in patients without or with moderate CA stenosis (15.9±4.6 % vs. 20.6±3.7 % (p&lt;0.001) and 19.6±3.0 % (p=0.003), respectively). Postexercise LV GLSS &lt;16.9% suggested a pronounced CA stenosis with a sensitivity of 80% and a specificity of 70% (area under the curve, AUC, 0.76±0.06 at 95 % confidence interval, CI, 0.63-0.89; р&lt;0.001). In the patient group without CA stenosis, LV GLSS showed a significant increase after completion of the exercise (from 19.1±3.1 to 20.6±3.7; p=0.04).Conclusion            Evaluation of LV GLSS and its dynamics in stress-EchoCG with a treadmill test may be promising in patients with IHD, since in most patients with pronounced CA stenosis, LV GLSS is reduced at baseline and further reduces in response to exercise. In patients without CA stenosis, LV GLSS increases after completing the exercise.

Longitudinal wall fractional shortening: an M-mode index based on mitral annular plane systolic excursion (MAPSE) that correlates and predicts left ventricular longitudinal strain (LVLS) in intensive care patients

Background

Left ventricular longitudinal strain (LVLS) is a modern measurement for LV function. However, strain measurement is often difficult in critically ill patients. We sought to show LVLS can be estimated using M-mode-derived longitudinal wall fractional shortening (LWFS), which is less dependent on image quality and is easier to perform in critically ill patients.

Methods

Transthoracic echocardiographic records were retrospectively screened and 80 studies suitable for strain and M-mode measurements in the apical 4-chamber view were selected. Longitudinal wall fractional shortening was derived from conventional M-mode (LWFS) and curved anatomical M-mode (CAMMFS). The relationships between LVLS and mitral annular plane systolic excusion (MAPSE) and M-mode-derived fractional shortening were examined using univariate generalized linear model in a training set (n = 50) and was validated in a separate validation set (n = 30).

Results

MAPSE, CAMMFS, and LWFS demonstrated very good correlations with LVLS (r = 0.852, 0.875 and 0.909, respectively). LWFS was the best unbiased predictor for LVLS (LVLS = 1.180 x LWFS - 0.737, P < 0.001). Intra- and inter-rater agreement and reliability for LWFS measurement were good.

Conclusions

LVLS can be estimated by LWFS in the critically ill patients. It provides a fast and accurate prediction of LVLS. LWFS is a reproducible and reliable measurement which can be used as a potential index in place of LVLS in the critically ill population.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1876-x) contains supplementary material, which is available to authorized users.