الفهرس 
RIGHT VENTRICULAR FUNCTION ASSESSMENTOnly 14 pages are availabe for public view
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Abstract
T
he right ventricle (RV) is a thin-walled chamber that functions at low oxygen demands and pressure. It is perfused throughout the cardiac cycle in both systole and diastole, and its ability to extract oxygen is increased during hemodynamic stress. All of these factors make the right ventricle less susceptible to infarction than the left ventricle. Isolated infarction of the right ventricle is extremely rare; right ventricular infarction usually is noted in association with inferior wall myocardial infarction.
Successful primary PCI in patients with Right ventricular myocardial infarction (RVMI) has been shown to normalize the RV systolic fraction and is associated with improved in-hospital mortality compared with patients in whom the intervention is unsuccessful. Reperfusion within 1 h of thrombus occlusion leads to immediate recovery of RV-free wall function and consequent improved LV filling and performance. Delayed reperfusion after 48 h is associated with a higher degree of RV dysfunction and complications, but still results in significant, yet slower, recovery of RV function.
Systolic RV function can be assessed by several methods. Cardiac magnetic resonance is considered the gold standard; however, it is limited by the cost and availability. There are many echocardiographic conventional parameters to investigate RV function. The RV fractional area change (RVFAC) , tricuspid annular plane systolic excursion (TAPSE) and Systolic TV Annular Velocity (S’ velocity). Tissue doppler imaging (TDI).
STE has been utilized to quantitatively assess the LV global and segmental myocardial function.
Fifty patients who underwent successful percutaneous coronary intervention (PCI) after inferior MI mainly associated with ECG criteria of RV infarction were prospectively included (55.92±8.77 years, 42 Men and 19 females).another fifty healthy individuals were examined (53.58±8.42 years) ”to obtain reference values for RV FWS”. Echocardiography (including 2D STE and conventional parameters for assessment of RV systolic function) was performed at baseline, and after a 3-month follow-up for all patients.
In the present study, baseline RV systolic function was reduced by different degrees early after primary PCI for inferior STEMI patients as assessed by conventional parameters as well as by strain parameters in the first 48 hours. RV FAC was the best parameter to assess RV function among conventional parameters (84%). RV FWS was the best parameter to detect RV function among advanced techniques.
All parameters improved at 3-month follow-up compared to baseline. Nevertheless, RV free wall strain (FWS) improved significantly for most of the patients.
Early reperfusion after acute inferior myocardial infarction results in immediate and sustained recovery of RV function reflected by improved RV FWS.
We concluded that at the acute phase of MI, TAPSE, S’ velocity, FAC and RV FWS were impaired by different degrees in the whole population and this means that the efficacy of these parameters as diagnostic tools is different and suggest that we may be underestimating the prevalence of RV injury in our post‐STEMI population if we only use classical echocardiographic parameters in order to make the diagnosis of RV infarction.
Our Recommendation is that STE should be applied in the routine assessment of patients presenting with RV infarction as it can detect early impairment and subsequent improvements of RV function.