Relationship between morphologic features of myocardial tissue and left ventricular function in patients with aortic...

The study aim was to investigate the correlation of myocardial fibrosis with myocardial remodeling and clinical outcome of aortic valve replacement (AVR) in patients with aortic stenosis and left ventricular (LV) hypertrophy.

Between 2007 and 2010, a total of 43 patients (23 males, 20 females; mean age 65.5 +/- 10.6 years; range: 33-84 years) underwent AVR at the authors' institution. During surgery, specimens (10 mm3) were obtained from the LV outflow tract and stained with Masson's trichrome. The fibrosis fraction (FF) was quantified. The mean follow up duration was 18.8 +/- 12.2 months (range: 0-46 months). Patients were allocated to either of two groups: the lower fibrosis (LF) group (n = 24) with FF < 5%, and the higher fibrosis (HF) group (n = 19) with FF > or = 5%.

There were no significant differences between the two groups in terms of preoperative NYHA functional class and complications. In total, 33 patients (19 LF and 14 HF) were followed up for at least six months. The preoperative LV mass index (LVMI) and LV ejection fraction (LVEF) were not significantly different between the two groups (p = 0.805 and p = 0.377, respectively). At the last follow up examination the LVMI showed a significant inter-group difference (LF group 111.4 +/- 23.2 g/m2; HF group 91.9 +/- 21.5 g/m2; p = 0.005), but the LVEF did not differ significantly between groups (p = 0.457). There was one early (non-cardiac) death in the LF group, and one early death and one late death (both cardiac-related) in the HF group.

In patients with aortic stenosis, a higher LVMI was not related to more severe myocardial fibrosis, and LV mass regression after AVR was not influenced by the severity of the myocardial fibrosis. Rather, cardiac-related death might be related to a highly fibrotic heart.