Cardio-omentopexy Reduces Cardiac Fibrosis and Heart Failure after Experimental Pressure Overload.
Ann Thorac Surg. 2018 Dec 12;:
Authors: Wang J, Zhang QJ, Pirolli TJ, Liu ZP, Powell L, Thorp EB, Jessen M, Forbess JM
BACKGROUND: The pedicled greater omentum has been shown to offer benefit in ischemic heart disease for both animal models and human patients. The impact of cardio-omentopexy in a pressure overload model of left ventricular hypertrophy (LVH) is unknown.
METHODS: LVH was created in rats by banding the ascending aorta after right thoracotomy (n=23). Sham surgery was performed in 12 additional rats. Six weeks post-banding, surviving LVH rats were assigned to cardio-omentopexy via left thoracotomy (LVH+Om, n=8) or sham left thoracotomy (LVH, n=8). Sham rats also underwent left thoracotomy for cardio-omentopexy (Sham+Om, n=6); the remaining animals underwent sham left thoracotomy (Sham, n=6).
RESULTS: Echocardiography 10-weeks post-cardio-omentopexy revealed LV end-systolic diameter, cardiomyocyte diamter, and myocardial fibrosis in the LVH group were significantly increased compared to LVH+Om, Sham+Om, and Sham groups (p<0.01). LV ejection fraction of the LVH group was lower than LVH+Om (p<0.01). Gene expression analysis revealed significantly lower sarcoendoplasmic reticulum calcium ATPase 2b (SERCA2b) levels in LVH rats compared to LVH+Om, Sham+Om, and Sham groups (p<0.01). In contrast, collagen type 1 alpha 1 chain (COL1a1), lysyl oxidase-like protein 1 (LOXL1), nuclear Protein-1 (NUPR1) and transforming growth factor-beta 1 (TGF-β1) in the LVH group were significantly higher than the LVH+Om cohort (p<0.01), consistent with a reduced fibrotic phenotype after omentopexy. Lectin staining showed myocardial capillary density of the LVH group was significantly lower than all other groups (p<0.01).
CONCLUSIONS: Cardio-omentopexy reduced cardiac dilation, contractile dysfunction, cardiomyocyte hypertrophy, and myocardial fibrosis, while maintaining other molecular indicators of contractile function in this LVH model.
PMID: 30552887 [PubMed – as supplied by publisher]