MMP3 and Left ventricular dilatation: Interestingly, in the small sample of hearts studied, there was no significant difference between patients with MMP3 expression regarding aetiology, severity of symptoms as measured by NYHA class, medication, or left ventricular dilation, although the abstract (which is as yet unpublished in full) did not specify whether there was any significant effect of ejection fraction on MMP3 expression.