Left ventricular global longitudinal strain following revascularization in acute ST elevation myocardial infarction - A comparison of primary angioplasty and Streptokinase-based pharmacoinvasive strategy

Early effect of different bifurcation techniques on left ventricular mechanics in elective percutaneous coronary intervention

BACKGROUND

Bifurcation lesions are prevalent amongst patients with symptomatic coronary artery disease subjected to percutaneous coronary intervention (PCI). Recent consensus commends a conservative (provisional) approach when managing the side branch. Here, the aim was to explore the immediate impact of different bifurcation techniques (one stent and two stent strategies) on left ventricular LV) myocardial functions using speckle tracking echocardiography in patients subjected to elective PCI. Sixty two consecutive patients diagnosed with coronary bifurcation lesion (CBL) were enrolled. Patients were categorized into: one-stent strategy (Provisional group, n = 44) and a two-stent strategy (TAP, DK crush, or Culotte technique, n = 18), based on the coronary bifurcation site, angle, side branch diameter and Medina classification. LVEF%, regional and global longitudinal strain (GLS), and E/E' were measured before and within 24 h post PCI.

RESULTS

In both provisional and 2- stent technique, the mitral inflow velocities and mitral annular velocities showed improvement with significant reduction in E/e' (P < 0.03 and P < 0.001) respectively while LVEF% did not change. There were no significant changes in any other echo parameters post PCI. In provisional group, there were significant improvements in LAD (P < 0.001), RCA (P < 0.01) territories and GLS (P < 0.01). Δ LAD was expressively higher (34.5%) compared with Δ LCX (9.6%) and ΔRCA (25.4%), P < 0.001, P < 0.01 respectively. In the 2-stent technique group, there were significant improvements in peak longitudinal strain of LAD territory (P < 0.01), RCA territory (P < 0.01) and GLS (P < 0.01) respectively. Δ LAD territory was significantly higher in provisional group in comparison with the 2- stent technique group. Δ GLS was correlated inversely to Gensini score in provisional group and to the number of vessel diseased in 2-stent technique group.

CONCLUSION

PCI of the bifurcation lesion positively impact myocardial function. Both bifurcation techniques improve LV mechanical properties using 2D strain imaging while LV EF% remains unchanged.

Speckle tracking echocardiography-derived left ventricular global longitudinal strain in ex-thalassaemics

AIMS

Long term survivors of haematopoietic stem cell transplantation (HSCT) for β-thalassemia major are designated "ex-thalassaemics". Whether ex-thalassaemics continue to harbour residual myocardial dysfunction and thereby stand the risk of heart failure-related morbidity and mortality is unknown. The aim of this study was to assess the prevalence and predictors of subclinical left ventricular (LV) dysfunction in an apparently normal ex-thalassaemic population.

METHODS

We conducted a single centre cross-sectional study among 62 ex-thalassaemic patients, who had undergone HSCT for β-thalassaemia major at our centre. The primary outcome variable was LV systolic dysfunction, as assessed by 1) LV global longitudinal strain (GLS) derived by 2D speckle tracking echocardiography and 2) LV ejection fraction (EF) derived by 2D Simpsons Biplane method.

RESULTS

Among the 62 patients included in the study, 7 [11.3%] were found to have LV systolic dysfunction, all of which were subclinical. Of these, 4 [6.5%] had abnormal GLS and LVEF, 2 [3.2%] had abnormal GLS with normal LVEF, and 1 [1.6%] had abnormal LVEF with low normal mean GLS. There were no statistically significant predictors of LV dysfunction in this cohort.

CONCLUSION

There was a high prevalence of subclinical myocardial dysfunction in the ex-thalassaemic population reiterating the need for close follow up of these patients. 2D Speckle tracking echocardiography-derived LV global longitudinal strain is an effective tool in detecting subclinical myocardial dysfunction in this cohort.

Left Ventricular Global Longitudinal Strain Following Acute ST-Elevation Myocardial Infarction - A Comparison of Primary Coronary Angioplasty and Tenecteplase-Based Pharmacological Reperfusion Strategy

Objective

In the setting of acute ST-elevation myocardial infarction (STEMI), reperfusion therapy with primary percutaneous coronary intervention (PCI) performed by an experienced team or pharmacological reperfusion with thrombolytic therapy is highly recommended. Standard echocardiographic measurement of the left ventricular ejection fraction (LVEF) is widely used to assess left ventricular global systolic function. This study was designed to compare the assessment of global left ventricular function by standard LVEF and global longitudinal strain (GLS) in the two well-known reperfusion strategies.

Materials and Methods

We conducted a retrospective single-center observational study in 50 patients with acute STEMI who underwent primary PCI (n = 25) and Tenecteplase (TNK)-based pharmacological reperfusion therapy (n = 25). The primary outcome was left ventricle (LV) systolic function after primary PCI, as assessed by two-dimensional (2D) GLS using speckle-tracking echocardiography (STE), as well as LVEF using standard 2D echocardiogram using Simpson's biplane method.

Results

Overall mean age was 53.7 ± 6.9 years with 88% male gender. The mean door-to-needle time was 29.8 ± 4.2 min in the TNK-based pharmacological reperfusion therapy arm, and the mean door-to-balloon time was 72.9 ± 15.4 min in the primary PCI arm. LV systolic function was significantly better in the primary PCI arm as compared to the TNK-based pharmacological reperfusion therapy, both by 2D STE (mean GLS: -13.6 ± 1.4 vs. -10.3 ± 1.2, P ≤ 0.001) and LVEF (mean LVEF: 42.2 ± 2.9 vs. 39.9 ± 2.7, P = 0.006). There were no significant differences in mortality and inhospital complications in both groups.

Conclusion

Global LV systolic function is significantly better after primary coronary angioplasty as compared to TNK-based pharmacological reperfusion therapy when assessed by routine LVEF and 2D GLS in the setting of acute STEMI.

Role of Speckle Tracking in the Evaluation of Left Ventricular Remodeling After Streptokinase Infusion in Patients with Acute Anterior Myocardial Infarction

Background. Left ventricular (LV) remodeling is an adverse consequence after acute myocardial infarction.Aim. To assess the role of speckle tracking in the evaluation of LV remodeling after streptokinase infusion in patients with acute anterior ST-segment elevation myocardial infarction (STEMI).Material and methods. A total of 200 patients with first acute anterior STEMI received streptokinase as a reperfusion therapy were included. Conventional echocardiography and speckle tracking were performed within 3 days of admission and 3 months later. According to the development of LV remodeling, patients were classified into two groups. Group (I) patients with LV remodeling (60 patients) and group (II) patients without remodeling (140 patients).Results. Patients with LV remodeling had lower global longitudinal (GLS) and circumferential (GCS) strain values (-13.19±4.57 vs. -18.90±4.23 % and -13.16±4.27 vs. -17.16±3.3 %, respectively, p<0.001). GLS cutoff value of >-13.5 was shown to have the best diagnostic accuracy (sensitivity =60.0% & specificity =87.1%) in predicting LV remodeling (AUC 0.816, 95% confidence interval [CI] 0.754-0.877, p<0.001). GCS cutoff value of >-16.21 was shown to have the best diagnostic accuracy (sensitivity =75.0% & specificity =71.4%) in predicting LV remodeling (AUC 0.785, 95%CI 0.719-0.85, p<0.001).Conclusion. Speckle tracking echocardiography either longitudinal or circumferential strain has good sensitivity and specificity in predicting LV remodeling after acute myocardial infarction.

Sonothrombolysis Improves Myocardial Dynamics and Microvascular Obstruction Preventing Left Ventricular Remodeling in Patients With ST Elevation Myocardial Infarction

Background:

It has recently been demonstrated that high-energy diagnostic transthoracic ultrasound and intravenous microbubbles dissolve thrombi (sonothrombolysis) and increase angiographic recanalization rates in patients with ST-segment–elevation myocardial infarction. We aimed to study the effect of sonothrombolysis on the myocardial dynamics and infarct size obtained by real-time myocardial perfusion echocardiography and their value in preventing left ventricular remodeling.

Methods:

One hundred patients with ST-segment–elevation myocardial infarction were randomized to therapy (50 patients treated with sonothrombolysis and percutaneous coronary intervention) or control (50 patients treated with percutaneous coronary intervention only). Left ventricular volumes, ejection fraction, risk area (before treatment), myocardial perfusion defect over time (infarct size), and global longitudinal strain were determined by quantitative real-time myocardial perfusion echocardiography and speckle tracking echocardiography imaging.

Results:

Risk area was similar in the control and therapy groups (19.2±10.1% versus 20.7±8.9%; P =0.56) before treatment. The therapy group presented a behavior significantly different than control group over time ( P <0.001). The perfusion defect was smaller in the therapy at 48 to 72 hours even in the subgroup of patients with no recanalization at first angiography (12.9±6.5% therapy versus 18.8±9.9% control; P =0.015). The left ventricular global longitudinal strain was higher in the therapy than control immediately after percutaneous coronary intervention (14.1±4.1% versus 12.0±3.3%; P =0.012), and this difference was maintained until 6 months (17.1±3.5% versus 13.6±3.6%; P <0.001). The only predictor of left ventricular remodeling was treatment with sonothrombolysis: the control group was more likely to exhibit left ventricular remodeling with an odds ratio of 2.79 ([95% CI, 0.13–6.86]; P =0.026).

Conclusions:

Sonothrombolysis reduces microvascular obstruction and improves myocardial dynamics in patients with ST-segment–elevation myocardial infarction and is an independent predictor of left ventricular remodeling over time.

Observational study of left ventricular global longitudinal strain in ST-segment elevation myocardial infarction patients with extended pharmaco-invasive strategy: A six months follow-up study

AIMS AND OBJECTIVES

To evaluate left ventricular (LV) function by assessment of LV global longitudinal strain (GLS) in ST-segment elevation myocardial infarction (STEMI) patients who underwent delayed fibrinolysis and coronary intervention (extended pharmaco-invasive strategy), since LV function is one of the determinants of both immediate and long-term outcomes.

METHODS

Prospective study of consecutive STEMI patients who underwent extended pharmaco-invasive strategy. The LV function was estimated using LV GLS at baseline and at 6 months.

RESULTS

The study included eighty-seven STEMI patients who received delayed pharmaco-invasive therapy and coronary intervention. The primary aim of the study was to evaluate a change in LV function by assessment of GLS at 6 months as compared to baseline. Prior to PCI, LV ejection fraction was 48.08 ± 6.23% and GLS was -11.11 ± 2.99%. Procedural success was achieved in all patients. LV ejection fraction after 6 months of follow-up increased to 53.12 ± 5.61% and the GLS improved to -13.03 ± 3.06% In comparison to baseline, there was a significant improvement in both LV ejection fraction and GLS at 6 months of follow-up (P < .001).The cardiac mortality was 1.1% at 6 months.

CONCLUSION

There is a significant improvement of LV function as assessed by GLS and ejection fraction at short-term follow-up. In a stable cohort of STEMI patients, extended pharmaco-invasive strategy is also a reasonable option if PCI cannot be performed within the first 24 hours, due to logistic and infrastructural constraints.