Higher baseline LVEF ( odds ratio , @ -LSB- @ % confidence interval , @ , @ -RSB- ; P < @ ) and previous permanent pacemaker ( odds ratio , @ -LSB- @ % confidence interval , @ , @ -RSB- ) were independently associated with reduced likelihood of @ % absolute LVEF improvement by @ days ; higher mean aortic valve gradient was associated with increased odds of LVEF improvement ( odds ratio , @ per @ mm Hg -LSB- @ % confidence interval , @ , @ -RSB- ) .