Early right ventricular dysfunction after primary percutaneous coronary intervention in anterior versus isolated inferior myocardial infarction assessed by tissue Doppler imaging and speckle tracking echocardiography.

This study hypothesized that imaging provides information indicating the right ventricular (RV) involvement after anterior or inferior ST-elevation myocardial infarction (STEMI), beyond standard electrocardiogram (ECG) due to the increasing interest in RV function and assessment techniques. This study aimed to compare RV function between anterior and inferior MI without RV involvement using different echocardiographic modalities. This study included 100 patients with anterior (50 patients) and inferior (50 patients) STEMI, who underwent primary percutaneous coronary intervention (PPCI) and two-dimensional echocardiographic imaging within 24 h after PPCI with RV function analysis by left ventricular (LV) infarct size, LV filling pressure, and RV strain rate. Our primary endpoint was the subclinical RV dysfunction in anterior or inferior MI using tissue Doppler and speckle tracking (STE). The study population included 80 (80%) males and 20 (20%) females. Patients with the anterior STEMI had higher mean creatine kinase-MB (CKMB) and troponin than those with inferior STEMI. This study revealed worse RV dysfunction in patients with anterior than those with inferior STEMI, as reflected by significantly lower RV systolic function, tricuspid annular plane systolic excursion (p ≤ 0.0001), tissue Doppler-derived velocity (p ≤ 0.0001), and STE-derived strain magnitude and rate (p ≤ 0.0001). RV dysfunction occurs in patients without ECG evidence of RV STEMI. RV dysfunction is worse in anterior than inferior MI. Moreover, RV systolic functions were affected by declined LV ejection fraction irrespective of the infarction site, which clinically implies prognostic, treatment, survival rate, and outcome improvement between both conditions. (Trial registration ZU-IRB#:4142/26-12-2017 Registered 26 December 2017, email: IRB_123@medicine.zu.edu.eg).

Relation of collateral circulation with reciprocal changes in patients with acute ST-elevation myocardial infarction.

OBJECTIVE: Acute STEMI is often accompanied by reciprocal ST-segment depression (RC) occurring in opposite leads, whose significance has been debated for decades. The possible role of collateral circulation in promoting RC in acute STEMI has not been identified. So our aim to find the relationship between collateral circulation and RC in STEMI patients treated with primary percutaneous intervention (PPCI). METHODS: The study included 112 pts. with acute STEMI underwent PPCI. The patients divided in to 2 groups: Group (A):66 pts. with RC, Group (B):46 pts without RC. All patients subjected to history taking, ECG [localization of infarction & RC], CKMB level, transthoracic echo [LVEF%], coronary angiography &PPCI to culprit artery and assess number of diseased vessels, site of occlusion, collaterals, TIMI flow pre and post PCI. RESULTS: Patients in group A with RC had shorter time to door, P < 0.001; more frequent inferior infarctions, P < 0.001; had higher CKMB level, P < 0.001; higher LVEDD, P < 0.001; LVESD, P < 0.001and lower LVEF, P = 0.004; had multi vessel diseases P = 0.02, increase incidence of RCA as a culprit artery <0.001 compared to patients with no RC. Patients with RC had significantly higher incidence of proximal LAD occlusion, distal RCA and distal LCX compared to patients without RC. The percentage of change was 61.2 ± 12.35% for ST elevation and 50.5 ± 10.87% for reciprocal ST depression post PCI with significance difference between them, t = 3.035P = 0.0023.There was no significant correlation between collateral circulation and RC. We found four significant independent predictors of RC. They were inferior infarction (P = 0.024), RCA as a culprit vessel, (P = 0.034), low EF, (P = 0.007) and multi-vessel disease, (P = 0.022). CONCLUSION: There is no correlation between concomitant RC and presence of collateral vessels in acute STEMI patients. So the pathogenesis of reciprocal ST-segment changes result from an interplay of ischemia at distance due to multi-vessel CAD and benign mirror electrical changes not caused by collateral circulation diverting blood to ischemic area from non-diseased artery.

Transmural Extent in Relation to Clinical Scoring in Non-ST Elevation Myocardial Infarction Patients: Speckle-Tracking Echocardiographic Study.

BACKGROUND: To assess the extent of transmurality in non-ST elevation myocardial infarction (NSTEMI) patients using speckle-tracking echocardiography (STE) in relation to their risk categorization to improve the risk stratification of NSTEMI patients through detecting the presence of transmural infarction. PATIENTS AND METHODS: It included 96 patients with NSTEMI. All patients were subjected to GRACE score (GS) calculation, transthoracic and speckle-tracking echocardiography (STE): To detect left ventricular ejection fraction and myocardial global longitudinal strain [GLS] and circumferential strain [CS]. RESULTS: As compared to low-GS group; high-risk group was older with the increased prevalence of hypertension (HTN), diabetes, and smoking. There was no significant difference between both groups regarding LS and CS of all 17 segments except for apex where longitudinal strain (LS) was significantly decreased in low-risk group (-17.2 ± 1.1) as compared to high-risk group (-18.6 ± 1.4). GLS was significantly decreased in high-risk group (15.4 ± 0.6) as compared to low-risk group (16 ± 0.8), P = 0.02 with no significant difference in the global CS (P = 0.8). Transmural infarction constitutes 37.5% of all patients. The prevalence of transmural infarction was increased in the low-risk group without significant difference. GS showed a positive correlation with age, male, HTN, diabetes, and smoking and negative correlation with GLS. There was no significant correlation between GS and global CS. Age, GS, and LS were significantly related to transmural infarction. None was found to predict the occurrence of transmural infarction. CONCLUSION: Transmural extent as detected by STE had been found in a relatively substantial number of patients with NSTEMI, and it may serve as a tool in conjunction with risk stratification scores for the selection of high-risk patients.