Recovery of regional systolic and diastolic myocardial function after acute myocardial infarction evaluated by two-dimensional speckle tracking echocardiography

Global longitudinal strain and the risk of major adverse cardiac events in post-myocardial infarction patients: A retrospective cohort study

BACKGROUND

This study evaluates the relationship between global longitudinal strain (GLS) and late major adverse cardiovascular events (MACEs) in patients after acute myocardial infarction (AMI).

METHODS

Data of newly diagnosed AMI patients between March 2010 and July 2014 were retrospectively evaluated. The patients underwent serial echocardiography at admission and at third and sixth months post-admission. We calculated GLS by averaging the strain from all myocardial segments using speckle-tracking echocardiography (STE). We used multivariate Cox regression analysis and receiver operating characteristic (ROC) curve analyses to assess the relationship between GLS at admission and late MACEs.

RESULTS

Eighty-nine newly diagnosed AMI patients were enrolled. The average age at diagnosis was 61 ± 12.5 years, and approximately 89.9% of the patients were men. The average level of GLS was -17.5 ± 3.9%. The overall prevalence of MACEs was 23.6% (21/89), compared with 44% (11/25) in the group with GLS≥-15% and 17.9% (5/28) in the group with GLS<-20%. GLS was positively linked with MACEs in the fully adjusted Cox proportional hazard model (hazard ratio [HR], 1.19; 95% confidence interval [CI], 1.04-1.37; P=0.014) after adjusting potential confounders. The ROC curve analysis for one year MACEs between GLS at admission, with the most significant area under the curve(AUC) 78.1% (95% CI, 63.8% - 92.6%).

CONCLUSIONS

Myocardial dysfunction, characterized by impaired GLS, is often observed in AMI patients, and a decrease in GLS levels at admission were associated with an increased risk of long-term MACEs in post-myocardial infarction patients.

Hypothermia for Cardioprotection in Acute Coronary Syndrome Patients: From Bench to Bedside

Early revascularization for patients with acute myocardial infarction (AMI) is of outmost importance in limiting infarct size and associated complications, as well as for improving long-term survival and outcomes. However, reperfusion itself may further damage the myocardium and increase the infarct size, a condition commonly recognized as myocardial reperfusion injury. Several strategies have been developed for limiting the associated with reperfusion myocardial damage, including hypothermia. Hypothermia has been shown to limit the degree of infarct size increase, when started before reperfusion, in several animal models. Systemic hypothermia, however, failed to show any benefit, due to adverse events and potentially insufficient myocardial cooling. Recently, the novel technique of intracoronary selective hypothermia is being tested, with preclinical and clinical results being of particular interest. Therefore, in this review, we will describe the pathophysiology of myocardial reperfusion injury and the cardioprotective mechanics of hypothermia, report the animal and clinical evidence in both systemic and selective hypothermia and discuss the potential future directions and clinical perspectives in the context of cardioprotection for myocardial reperfusion injury.

Peak early diastolic strain rate improves prediction of adverse cardiovascular outcomes in patients with ST-elevation myocardial infarction

BACKGROUND

The prognostic role of diastolic dysfunction measured by the circumferential peak early diastolic strain rate (PEDSR) on ST-elevation myocardial infarction (STEMI) is not completely established.

OBJECTIVES

We aimed to investigate the prognostic value of diastolic function by measuring PEDSR within 1 week after STEMI.

METHODS

The cardiac magnetic resonance (CMR) pictures of 420 subjects from a clinical registry study (NCT03768453) were analyzed and the composite major adverse cardiac events (MACEs) were followed up.

RESULTS

The PEDSR of patients was significantly lower compared with that of control subjects (P < 0.001). Within the median follow-up period of 52 months, PEDSR of patients who experienced MACEs deceased more significantly than that of patients without MACEs (P < 0.001). After adjusting with clinical or CMR indexes, per 0.1/s reduction of PEDSR increased the risks of MACEs to 1.402 or 1.376 fold and the risk of left ventricular (LV) remodeling to 1.503 or 1.369 fold. When PEDSR divided by best cutoff point, significantly higher risk of MACEs (P < 0.001) and more remarkable LV remodeling (P < 0.001) occurred in patients with PEDSR ≤ 0.485/s. Moreover, when adding the PEDSR to the conventional prognostic factors such as LV ejection fraction and infarction size, better prognostic risk classification models were created. Finally, aging, tobacco use, remarkable LV remodeling, and a low LV ejection fraction were factors related with the reduction of PEDSR.

CONCLUSIONS

Diastolic dysfunction has an important prognostic effect on patients with STEMI. Measurement of the PEDSR in the acute phase could serve as an effective index to predict the long-term risk of MACEs and cardiac remodeling.

Left-Side Pressure Index for All-Cause Mortality in Older Adults with HFpEF: Diagnostic Potential for HFpEF and Possible View for HFrEF

Heart failure (HF) with preserved ejection fraction (HFpEF) is thought to be driven by increased cardiac afterload, which consequentially leads to left ventricular (LV) diastolic dysfunction. The ratio of LV diastolic elastance (Ed) to arterial elastance (Ea) significantly increases in older hypertensive women without HF and is coincident with cardiac structural alterations. Ed/Ea is reported to be a prognostic factor for all-cause mortality in patients admitted with HFpEF. In this short article, I provide a possible view of this novel index as having diagnostic potential for HFpEF in clinics and playing a prognostic role in HF with reduced ejection fraction (HFrEF).

Three-Dimensional Echocardiography and Coagulation Function Detection in the Prognosis Evaluation of Patients with Acute Myocardial Infarction

This research was aimed at discussing the application value of coagulation function detection and three-dimensional echocardiography in the prognosis evaluation of acute myocardial infarction (AMI) patients. 72 patients with AMI were divided into the recovered group (good recovery) and unrecovered group (poor recovery) according to the results of postoperative ultrasonography. The left ventricular parameters of the patients were detected by three-dimensional ultrasound, and the coagulation function was also detected. The results showed that 3 months after surgery, the regional end-systolic volume (rESV) and regional end-diastolic volume (rEDV) of the left ventricle in the patients were smaller than the measured values 1 week after surgery. The left ventricular regional ejection fraction (rEF) was greater than the value measured 1 week after surgery, and all the differences were statistically significant (P < 0.05). For the end-systolic volume (ESV), end-diastolic volume (EDV), and ejection fraction (EF) (%), the two-dimensional ultrasound results were significantly lower than the three-dimensional ultrasound results, and there were significant differences (P < 0.05). Tmsvle6-Dif% of the recovered patients was 14.99 ± 9.88 and 14.37 ± 9.78 3 months and 6 months after surgery, respectively. These were smaller than 30.91 ± 18.63 and 33.51 ± 17.96 of the unrecovered patients; the differences were of statistical significance (P < 0.05). Tmsvl6-SD% of recovered patients was 3.69 ± 2.47 and 3.61 ± 1.83 3 months and 6 months after surgery, respectively, which were also smaller than 7.38 ± 4.06 and 7.96 ± 2.82 of unrecovered patients, showing statistically significant difference (P < 0.05). The postoperative Tmsvle6-Dif% and Tmsvl6-SD% of the recovered group were lower than those of the unrecovered patients, with the statistically significant differences (P < 0.05). The level of coagulation factors in the recovered group was also significantly lower than that in the unrecovered group with the difference statistically significant (P < 0.05). The results suggested that three-dimensional echocardiography played an important role in the evaluation of cardiac conditions in AMI patients. The level of coagulation factors varied with the AMI condition of patients, and there was an obvious relationship between them, which could provide a reference value for the prognosis evaluation of patients.

[Applicability of the load dynamometric test and speckle tracking echocardiography in the heart failure with preserved ejection fraction diagnosis]

Aim    To compare myocardial deformation properties in patients with heart failure (HF) with preserved left ventricular ejection fraction (HFpEF) and in healthy volunteers at rest and during a dynamometric test; to determine a possibility of using this method for diagnosing HSpEF.Material and methods    STE with simultaneous electrocardiogram recording was performed for patients with HSpEF and healthy volunteers of the control group at rest and during a dynamometric test. The subjects were instructed to maintain a submaximal compression of a hand dynamometer for 3 min and to apply a maximum effort during the last 30 sec while continuing to breathe regularly. Concentrations of markers for myocardial injury and HF were measured. Statistical analytical methods are provided in Results. For other calculations, a MS Office (Microsoft Excel) application software package was used.Results    Differences in myocardial deformation variables between healthy volunteers and HF patients were more obvious during exercise, including changes of the variables from the resting values. As compared with the control group, patients with HFpEF had considerable deviations of the heart rate and the left ventricular global longitudinal strain (GLSLV) (significance of differences calculated with ANOVA was higher than 95% and 80%; p&lt;0.05 and p&lt;0.2, respectively). Patients with a significant change in the strain, regardless of the direction of the change, showed a decrease in the left ventricular ejection fraction (EFLV) during the test with a probability above 95% according to the Fischer test. Also, patients with HFpEF had higher concentrations of N-terminal pro-brain natriuretic peptide and symptoms of HF. Compared to evaluation of overall GLSLV, calculation of deformation variables by segment detected more differences between patients with HFpEF and control subjects.Conclusion    STE with a dynamometric test is an effective, noninvasive method for diagnosing HFpEF that is easy to perform in the outpatient conditions.

Prognostic impact of non-improvement of global longitudinal strain in patients with revascularized acute myocardial infarction

Global longitudinal strain (GLS) is a more sensitive prognostic factor than left ventricular ejection fraction (LVEF) in various cardiac diseases. Little is known about the clinical impact of GLS changes after acute myocardial infarction (AMI). The present study aimed to explore if non-improvement of GLS after 3 months was associated with higher risk of subsequent composite cardiovascular events (CCVE). Patients with AMI were consecutively included at a secondary care center in Norway between April 2016 and July 2018 within 4 days following percutaneous coronary intervention. Echocardiography was performed at baseline and after 3 months. Patients were categorized with non-improvement (0 to - 100%) or improvement (0 to 100%) in GLS relative to the baseline value. Among 214 patients with mean age 65 (± 10) years and mean LVEF 50% (± 8) at baseline, 50 (23%) had non-improvement (GLS: - 16.0% (± 3.7) to - 14.2% (± 3.6)) and 164 (77%) had improvement (GLS: - 14.0% (± 3.0) to - 16.9% (± 3.0%)). During a mean follow-up of 3.3 years (95% CI 3.2 to 3.4) 77 CCVE occurred in 52 patients. In adjusted Cox regression analyses, baseline GLS was associated with all recurrent CCVE (HR 1.1, 95% CI 1.0 to 1.2, p < 0.001) whereas non-improvement versus improvement over 3 months follow-up was not. Baseline GLS was significantly associated with the number of CCVE in revascularized AMI patients whereas non-improvement of GLS after 3 months was not. Further large-scale studies are needed before repeated GLS measurements may be recommended in clinical practice.Trial registration: Current Research information system in Norway (CRISTIN). Id: 506563.

The Blinding Period Following Ablation Therapy for Atrial Fibrillation: Proarrhythmic and Antiarrhythmic Pathophysiological Mechanisms

Atrial fibrillation (AF) causes heart failure, ischemic strokes, and poor quality of life. The number of patients with AF is estimated to increase to 18 million in Europe in 2050. Pharmacological therapy does not cure AF in all patients. Ablative pulmonary vein isolation is recommended for patients with drug-resistant symptomatic paroxysmal AF but is successful in only about 60%. In patients in whom ablative therapy is successful on the long term, recurrence of AF may occur in the first weeks to months after pulmonary vein ablation. The early recurrence (or delayed cure) of AF is not understood but forms the basis for the generally accepted 3-month blinding (or blanking) period after ablation therapy, which is not included in the evaluation of the eventual success rate of the procedures. The underlying pathophysiological processes responsible for early recurrence and the delayed cure are unknown. The implicit assumption of the blinding period is that the AF mechanism in this period is different from the ablation-targeted AF mechanism (ectopy from the pulmonary veins). In this review, we evaluate the temporary and long-lasting pro- and antiarrhythmic effects of each of the pathophysiological processes and interventions (necrosis, ischemia, oxidative stress, edema, inflammation, autonomic nervous activity, tissue repair, mechanical remodeling, and use of antiarrhythmic drugs) occurring in the blinding period that can modulate AF mechanisms. We propose that stretch-reducing ablation scar is a permanent antiarrhythmic mechanism that develops during the blinding period and is the reason for delayed cure.