**3.2 Anatomy and pathophysiology**

Some studies have elucidated that gender differences in the prognosis of patients with coronary artery disease after PCI are due to the fundamental differences in physiology, pathophysiology, pathological anatomy, and other aspects between male and female. Anatomically, the coronary arteries of female patients with coronary artery disease are smaller than that of male patients with those, and the smaller blood vessels can cause higher risks of bleeding complications and vascular damage [22]. In general, male patients with coronary artery disease are prone to complex lesions, such as left main artery lesions, chronic total occlusion lesions, and long lesions, while female patients with coronary artery disease tend to have small vessel lesions, which are more likely to show no significant stenosis of the coronary artery during coronary angiography [23]. Meanwhile, coronary microvascular reactivity and myocardial response to ischemia are also different between male and female individuals. It is suggested that the hemodynamic state of female patients with coronary artery disease is worse than that of male patients with those, which leads to differences of cell cycle process and apoptosis-related protein levels of cardiac fibroblasts between different genders [24]. In addition, female patients with myocardial infarction often show atypical symptoms [25]. As a result, such patients will not be paid much attention to, and physicians may be misled or underestimate the possibility of acute coronary syndrome, thereby prolonging the time from myocardial infarction to revascularization [26]. These pathophysiology and anatomy differences are irreversible factors. If the physiological and pathological characteristics of female patients with coronary artery disease can be identified in time, appropriate coronary intervention strategies will be selected to reduce complications and improve their clinical prognosis.
