[Aortic valve surgery: unveiling the mystery of a woman's heart].

See articleS on pageS 31-8 Several studies have reported a significant association between female gender and increased operative mortality following cardiac surgery including valve surgery. 1 However, it remains unclear whether or not female gender is really an independent risk factor or simply a marker for other factors. The article published by Caballero-Borrego et al in this issue of Revista Española de Cardiología 2 provides new insights in this regard. In this series of 577 patients with severe aortic stenosis (SAS) undergoing aortic valve replacement, the operative mortality was 2-fold higher in women (13%) than in men (7%). However, after adjustment for other potential confounders, including body surface area, female gender was no longer a significant predictor of mortality on multivariate analysis. Hence, in light of these findings, female gender does not appear to be an independent risk factor for operative mortality following aortic valve surgery. Nonetheless, it is important, from both scientific and clinical standpoints, to identify the factors that may be responsible for the increased perioperative morbidity and mortality that is typically observed in women. Identification of the causal factors, especially if they are modifiable, could indeed help to improve the outcome of aortic valve replacement in this specific population. Some studies have demonstrated that, for the same degree of left ventricular (LV) pressure overload, i.e. the same levels of transvalvular pressure gradients in the case of aortic stenosis, women tend to have more pronounced concentric LV remodelling and hypertrophy compared to men. 3 In this regard, it has been reported that severe LV concentric remodelling is associated with increased risk of operative mortality following aortic valve replacement. 4 The specific hormonal, metabolic, and physiological status associated with female gender can modulate the LV compensatory response to pressure overload. The exaggerated concentric remodelling may, in turn, accelerate impairment of coronary microcirculation and development of LV diastolic dysfunction. Moreover, a recent study from our group has reported that patients with a small concentric remodelled ventricle often have reduced stroke volume and thereby low transvalvular gradient despite the presence of SAS and preserved LV ejection fraction. 5 Interestingly, this " paradoxical low flow, low gradient SAS " was more frequent in women and it was associated with worse outcome, especially when treated medically. Another intriguing result of the study of Caballero-Borrego et al 2 is that women were older and had higher transvalvular gradients and higher prevalence of heart failure …