[Distribution of cardioplegia by retrograde approach. Cannula of retrograde cardioplegia with manually inflating balloon versus self-inflating balloon].

Retrograde cardioplegia is still debated due to heterogeneous left ventricular flow distribution. The purpose of this study was to compare retrograde flow distribution delivered through the coronary sinus with two patterns of cannula. Fifty four patients were prospectively randomized to receive cold crystalloid retrograde coronary sinus cardioplegia with lither a manual inflating balloon cannula (group I, 24 patients) or a self-inflating balloon cannula (group II, 30 patients). Left ventricular distribution of the cardioplegic solution was assessed by monitoring the left ventricular wall temperatures (anterior and posterior). The cardioplegic retrograde infusion was stopped as the anterior wall temperature reached 12 degrees C. In group II, 70.8% of patients had an identical cooling in the anterior and posterior wall of the left ventricle, versus 40.9% in group I (p < 0.05). The mean temperature difference between anterior and posterior wall was 2.9 degrees C (standard deviation: 2.9 degrees C) in group II versus 5.7 degrees C (standard deviation: 4.3 degrees C) for group I (< 0.05). The retroplegia cannula with the self-inflating balloon allows a better distribution of the cardioplegia flow than the manually inflating balloon. We think that this is due to the shape of the self-inflating balloon which more closely fits the morphology of the coronary sinus.