Introduction
The prevalence of valvular heart disease (VHD) is estimated to be 2.5%
in developed nations and increases with age, occurring in 14.0% and
12.6% of males and females over the age of 75, respectively [1,2].
Mitral valve disease (MVD) is the most common valvular lesion, with at
least moderate mitral regurgitation (MR) occurring in 1.7% of all
individuals and 9.3% of those over the age of 75 [2]. The only
definitive treatment for MVD is surgical repair or replacement with a
mechanical or bioprosthetic valve. Consideration for MV surgical
intervention depends on the expected outcomes associated with various
preoperative and intraoperative factors and sex is a factor that has
been demonstrated to influence these factors [8, 14].
Preoperatively, females are referred later in the disease process with
generally higher rates of comorbidities [11-15]. Intraoperatively,
there is an increased likelihood of MVR over repair for females compared
to males [12, 13, 15] and an increased likelihood of concomitant
procedures [13, 14]. Postoperatively, studies have demonstrated
inferior outcomes for females as compared to males in MV surgery, with
up to a 2.5x increased mortality for females aged 40-59 [11, 12, 18,
19]. While it is well known that the heart remodels after MV surgery,
there is little evidence on the impact of sex on cardiac remodeling post
MV surgery.
Cardiac remodeling is an integral part of valvular and other cardiac
diseases. Changes to hemodynamics, chamber pressure, metabolism,
inflammation, and a multitude of other mechanisms can lead to remodeling
of the cardiac chambers . In the context of MV disease, cardiac
remodeling most often includes left atrial (LA) and left ventricular
(LV) dilation as well as an increased LV ejection fraction (LVEF). The
consequences of cardiac remodeling include development of arrhythmias
and heart failure [20, 21]. It is therefore imperative to understand
the factors influencing cardiac remodeling after MV surgery as reversal
of pathological remodeling may impact an individual’s recovery and
long-term prognosis.
Although higher rates of comorbidities and delayed surgical referral may
explain the inequity in MV surgery outcomes between males and females,
there have been no factors definitively identified as having a causal
effect. The current literature seeking to identify the impact of sex and
surgical approach on postoperative cardiac remodeling and outcomes is
insufficient. Consequently, identical guidelines are used to treat both
sexes while females continue to suffer inferior postoperative outcomes.
Current trends in medicine seek to personalize treatments for individual
patients. In order to minimize the disease burden and optimize quality
of life, treatment in MVD should also be tailored to an individual’s
specific presentation. In this propensity-matched retrospective study,
we look to identify variations in postoperative cardiac remodeling and
outcomes between males and females who have undergone MVR to better
inform the clinical decision-making process for patients requiring
surgical MVR.