Detecting Acute Myocardial Infarction by Diffusion-Weighted versus T2-Weighted Imaging and Myocardial Necrosis Markers

Adaptation of closed-chest infarction porcine model to adult Pannon minipigs

The aim of the recent study was to collect data on the genotype characteristics of the Hungarian self-bred Pannon minipigs by adapting a standardized infarct model procedure. Closed chest AMI was induced by balloon occlusion for 90 min in the left anterior descendent coronary artery (LAD) in 24 adult intact female minipigs followed by reperfusion. To assess the left ventricular (LV) function, serial cardiac magnetic resonance imaging (cMRI) was performed prior to the experimental procedure, on day 3 post-AMI (72 ± 12 h), and at 1 month follow-up (Day 30 ± 2 days). Compared to baseline cMRI scans the end-diastolic volume (EDV) was increased on days 3 and 30 On day 3 the left ventricular ejection fraction (LVEF) decreased significantly but there was no statistical difference between the baseline and day 30 measurements. Cardiac output, stroke volume, and end-systolic volume significantly were increased compared to baseline on day 30 A high percentage (54%) of malignant arrhythmias occurred during the AMI procedure, with a 25% mortality rate. The compensatory capacity of the Pannon minipig heart is excellent therefore the use of different cardiac parameters and invasive measurements is advisable in chronic pharmacological experiments to complement cMRI data.

Myocardium microcirculation study in a healthy Chinese population using 3.0-T cardiac magnetic resonance intravoxel incoherent motion imaging

BACKGROUND

Intravoxel incoherent motion imaging (IVIM) can non-invasively evaluate diffusion and microvascular perfusion.

PURPOSE

To explore the myocardium microcirculation of a healthy Chinese population by using cardiac magnetic resonance (CMR) IVIM.

MATERIAL AND METHODS

A total of 80 healthy volunteers (44 men, 36 women) who underwent 3.0-T CMR examination were enrolled. All participants had cardiac cine imaging and short-axis CMR-IVIM of the left ventricle (LV) using multiple b-values. The consistency of the IVIM parameters was assessed by intraclass correlation coefficient (ICC) and the Bland-Altman test. Spearman correlation analysis was performed between IVIM parameters and age, and body mass index (BMI). The differences of IVIM parameters were analyzed between gender and different ages.

RESULTS

LV end-diastolic volume (EDV), end-systolic volume (ESV), LVmass, cardiac output (CO), and BMI in the male group were higher than those in the female group (P<0.05). IVIM parameters had good intra-observer and inter-observer consistency (≥0.75). Bland-Altman analysis also showed good intra-observer and inter-observer consistency. ADC_fast decreased with increasing female age (rs = -0.37; P = 0.01), while IVIM parameters had no correlation with BMI regardless of sex. ADC_fast in the female group had a statistical difference between different age groups. The ADC_slow and f in the male group were lower than those in the female group (P<0.05); however, there was no statistical difference in ADC_fast between genders.

CONCLUSION

IVIM parameters in healthy Chinese volunteers provided good consistency. There was a negative correlation between ADC_fast and age in the female group.

Role of Platelet Activation and Oxidative Stress in the Evolution of Myocardial Infarction

Myocardial infarction, commonly known as heart attack, evolves from the rupture of unstable atherosclerotic plaques to coronary thrombosis and myocardial ischemia–reperfusion injury. A body of evidence supports a close relationship between the alterations following an ischemia–reperfusion injury-induced oxidative stress and platelet activity. Through their critical role in thrombogenesis and inflammatory responses, platelets are fully (totally) implicated from atherothrombotic plaque formation to myocardial infarction onset and expansion. However, mere platelet aggregation prevention does not offer full protection, suggesting that other antiplatelet therapy mechanisms may also be involved. Thus, the present review discusses the integrative role of platelets, oxidative stress, and antiplatelet therapy in triggering myocardial infarction pathophysiology.

Dynamic Monitoring of Erythrocyte Distribution Width (RDW) and Platelet Distribution Width (PDW) in Treatment of Acute Myocardial Infarction

Background

This study investigated the role of erythrocyte distribution width (RDW) and platelet distribution width (PDW) in evaluating the treatment efficacy for acute myocardial infarction (AMI).

Material/Methods

A total of 120 AMI patients receiving conventional myocardial infarction treatment were included. The patients were divided into an effective group and an ineffective group based on treatment efficacy. The RDW and PDW were measured before and after treatment. We used the independent samples t test, chi-square test, logistic regression, and ROC curves for analysis.

Results

The change and change rate of RDW and PDW were significantly improved (p<0.01) and the positive change rate of RDW, PDW, and RDW + PDW were significantly lower in the effective group compared with those in the ineffective group (p<0.01). The change and change rate of RDW and PDW are independent factors for treatment efficacy evaluation (p<0.05). ROC curve analysis showed that the changes and change rate of RDW and PDW were all significant in evaluating treatment efficacy (p<0.05).

Conclusions

The change and change rate of RDW and PDW or their combination can be used to evaluate treatment efficacy; however, the absolute value of RDW and PDW are not as significant.