Right ventricular involvement in anterior myocardial infarction: a translational approach

The aim of the present study was to evaluate the involvement of the right ventricle (RV) in reperfused anterior ST-elevation myocardial infarction (STEMI). Left anterior descending (LAD)-perfused area (using thioflavin-S staining after selective infusion in proximal LAD artery, %), infarct size (using triphenyltetrazolium chloride staining, %), and salvaged myocardium (% of LAD-perfused area) in the right and left ventricle (LV) were quantified in a 90-min LAD occlusion 3-day reperfusion model in swine (n = 8). Additionally, we studied, using cardiovascular magnetic resonance, 20 patients with a first STEMI due to proximal LAD occlusion treated with primary angioplasty. Area at risk (T2-weighted sequence, %), infarct size (late enhancement imaging, %), and salvaged myocardium (% of area at risk) in the right and LV were quantified. In swine, a large LAD-perfused area was detected both in the right and LV (30 +/- 5 vs. 62 +/- 15%, P < 0.001) but more salvaged myocardium (94 +/- 6 vs. 73 +/- 11%, P < 0.001) resulted in a smaller right ventricular infarct size (2 +/- 1 vs. 16 +/- 5%, P < 0.001). Similarly, in patients a large area at risk was detected both in the right and LV (34 +/- 13 vs. 43 +/- 12%, P = 0.02). More salvaged myocardium (94 +/- 10 vs. 33 +/- 26%, P < 0.001) resulted in a smaller infarct size (2 +/- 3 vs. 30 +/- 16%, P < 0.001) in the RV. In reperfused extensive anterior STEMI, a large area of the RV is at risk but the resultant infarct size is small.