COMBINING PERCUTANEOUS BYPASS WITH CORONARY RETROPERFUSION LIMITS MYOCARDIAL NECROSIS

After an acute coronary occlusion that results in hemodynamic instabil ity, the institution of percutaneous bypass (PB) can effectively suppo rt the failing myocardium. However, ph cannot augment coronary blood f low and substantial regional myocardial necrosis can still occur. This experimental study was undertaken to determine whether combining ph w ith coronary venous retroperfusion using pressure-controlled intermitt ent coronary sinus occlusion (PICSO) would limit myocardial necrosis a fter an acute coronary occlusion. In 30 pigs, the second and third dia gonal vessels were occluded with snares for 90 minutes followed by 30 minutes of cardioplegic arrest and 180 minutes of reperfusion with the snares released. During the period of coronary occlusion, 10 pigs wer e placed on PB, 10 pigs received PB + PICSO, and 10 pigs received no s upport (unmodified). Hearts treated with the combination of PB + PICSO had the highest wall motion scores (unmodified, 1.4 +/- 0.3; PB, 1.4 +/- 0.3; PB + PICSO, 2.8 +/- 0.3 [p < 0.05 versus unmodified and PB]) and the lowest area of necrosis in the area at risk (unmodified, 73% /- 3%; PB, 43% +/- 2%; PB + PICSO, 14% +/- 2% [p < 0.05, PB and PB + P ICSO versus unmodified; p < 0.05, PB + PICSO versus PB]). We conclude that combining PB with coronary venous retroperfusion significantly li mits myocardial necrosis.