at transient changes preload and afterload in the maternal Despite many reports on maternal cardiac adaption CARDIOVASCULAR

parameters are load dependent, so the use ofProvince, China Full list of author information is available at the end of the articleheart. Those changes are necessary for the progression of a successful pregnancy, but which may also impose further load on the heart. Moreover, heart disease is the leading cause of nonobstetric mortality during preg-nancy [1], and the number of pregnant women at risk for cardiovascular complications is on the rise [2]. Therefore, being published, there is controversy about the change in left ventricular (LV) performance during pregnancy. Although it is reported that an increased cardiac output (CO) is paralleled by a decreased peripheral vascular re-sistance, the documents on the enlargement of chamber size, LV wall thickness and mass are inconsistent [3,4]. More controversial is in regards to the adjustment of LV functions. The parameters of myocardial systolic function, including ejection fraction (EF), shortening fraction and tissue Doppler velocity, have been variously described as decreased [5], increased [6] or remained constant [7]