Retrograde coronary sinus perfusion for myocardial protection

Summary

To investigate the effectiveness of retrograde coronary sinus perfusion with cold cardioplegic solution for myocardial protection, we subjected 20 rabbit hearts to 90-minute-aortic-cross-clamping, and divided them into two groups: group 1 undergoing 3-minute retrograde cardioplegic perfusion every 20 min during aortic cross-clamping; gioup 2, simple hypothermia. Time of cardiac arrest and resuscitation were 2.17±1.17 and l.56± 1.13 min in group l, while 16.37±5.52 and 5.14±2.34 min in group 2, there being significant differences between both groups. After re-perfusion, LDH values in group 2 were apparently higher than those in group 1, but there was no significant difference in myocardial water content between both groups. Election-microscopically, there was severer myocaidial injury in gioup 2, but slight injury in group 1. This study demonstrated that retrograde cardioplegic perfusion could provide an excellent protection for myocardium subjected to 90-minute-aortic-cross-clamping, thereby constituting its significant superiority to simple hypothermia.