2026-04-17T22:03:52Zhttps://repisalud.isciii.es/rest/oai/request

oai:repisalud.isciii.es:20.500.12105/166642024-09-27T09:48:43Zcom_20.500.12105_19604com_20.500.12105_2051col_20.500.12105_19605

00925njm 22002777a 4500 dc Fernández-Jiménez, Rodrigo author García-Prieto, Jaime author Sánchez-González, Javier author Agüero, Jaume author López-Martín, Gonzalo J author Galán-Arriola, Carlos author Molina-Iracheta, Antonio author Doohan, Roisin author Fuster, Valentin author Ibáñez, Borja author 2015-08-18 BACKGROUND Post-ischemia/reperfusion (I/R) myocardial edema was recently shown to follow a consistent bimodal pattern: an initial wave of edema appears on reperfusion and dissipates at 24 h, followed by a deferred wave that initiates days after infarction, peaking at 1 week. OBJECTIVES This study examined the pathophysiology underlying this post-I/R bimodal edematous reaction. METHODS Forty instrumented pigs were assigned to different myocardial infarction protocols. Edematous reaction was evaluated by water content quantification, serial cardiac magnetic resonance T2-mapping, and histology/immunohistochemistry. The association of reperfusion with the initial wave of edema was evaluated in pigs undergoing 40-min/80-min I/R and compared with pigs undergoing 120-min ischemia with no reperfusion. The role of tissue healing in the deferred wave of edema was evaluated by comparing pigs undergoing standard 40-min/7-day I/R with animals subjected to infarction without reperfusion (chronic 7-day coronary occlusion) or receiving post-I/R high-dose steroid therapy. RESULTS Characterization of post-I/R tissue changes revealed maximal interstitial edema early on reperfusion in the ischemic myocardium, with maximal content of neutrophils, macrophages, and collagen at 24 h, day 4, and day 7 post-I/R, respectively. Reperfused pigs had significantly higher myocardial water content at 120 min and T2 relaxation times on 120 min cardiac magnetic resonance than nonreperfused animals. Permanent coronary occlusion or high-dose steroid therapy significantly reduced myocardial water content on day 7 post-infarction. The dynamics of T2 relaxation times during the first post-infarction week were altered significantly in nonreperfused pigs compared with pigs undergoing regular I/R. CONCLUSIONS The 2 waves of the post-I/R edematous reaction are related to different pathophysiological phenomena. Although the first wave is secondary to reperfusion, the second wave occurs mainly because of tissue healing processes. J Am Coll Cardiol. 2015 Aug 18;66(7):816-828. http://hdl.handle.net/20.500.12105/16664 26271065 10.1016/j.jacc.2015.06.023 1558-3597 Journal of the American College of Cardiology Pathophysiology Underlying the Bimodal Edema Phenomenon After Myocardial Ischemia/Reperfusion.