title: Maternal Cardiovascular Function in Normal Pregnancy: Evidence of Maladaptation to Chronic Volume Overload.
abstract: The aim of this study was to investigate cardiac functional status in pregnancy using a comprehensive approach taking into account the simultaneous changes in loading and geometry, as well as maternal age and anthropometric indices. This was a prospective cross-sectional study of 559 nulliparous pregnant women assessed at 4 time points during pregnancy and at 1 year postpartum. All women underwent conventional echocardiography and tissue Doppler velocities and strain rate analysis at multiple cardiac sites. Mean arterial pressure and total vascular resistance index significantly decreased (both P<0.001) during the first 2 trimesters of pregnancy and increased thereafter. Stroke volume index and cardiac index showed the opposite trend compared with mean arterial pressure and total vascular resistance index (both P<0.05). Myocardial and ventricular function were significantly enhanced in the first 2 trimesters but progressively declined thereafter. By the end of pregnancy, significant chamber diastolic dysfunction and impaired myocardial relaxation was evident in 17.9% and 28.4% of women, respectively, whereas myocardial contractility was preserved. There was full recovery of cardiac function at 1 year postpartum. Cardiovascular changes during pregnancy are thought to represent a physiological adaptation to volume overload. The findings of a drop in stroke volume index, impaired myocardial relaxation with diastolic dysfunction, and a tendency toward eccentric remodeling in a significant proportion of cases at term are suggestive of cardiovascular maladaptation to the volume-overloaded state in some apparently normal pregnancies. These unexpected cardiovascular findings have important implications for the management of both normal and pathological pregnancy states.
authors.affiliation: From the Fetal Maternal Medicine Unit, Department of Obstetrics and Gynaecology, St George's University of London, London, United Kingdom (K.M., A.K., B.T.); Department of Obstetrics and Gynecology, Santo Spirito Hospital, Pescara, Italy (K.M.); and Department of Cardiology and Cardiothoracic Surgery, St George's University of London, London, United Kingdom (R.S.).
authors.forename: Karen
authors.initials: K
authors.lastname: Melchiorre
authors.affiliation: From the Fetal Maternal Medicine Unit, Department of Obstetrics and Gynaecology, St George's University of London, London, United Kingdom (K.M., A.K., B.T.); Department of Obstetrics and Gynecology, Santo Spirito Hospital, Pescara, Italy (K.M.); and Department of Cardiology and Cardiothoracic Surgery, St George's University of London, London, United Kingdom (R.S.).
authors.forename: Rajan
authors.initials: R
authors.lastname: Sharma
authors.affiliation: From the Fetal Maternal Medicine Unit, Department of Obstetrics and Gynaecology, St George's University of London, London, United Kingdom (K.M., A.K., B.T.); Department of Obstetrics and Gynecology, Santo Spirito Hospital, Pescara, Italy (K.M.); and Department of Cardiology and Cardiothoracic Surgery, St George's University of London, London, United Kingdom (R.S.).
authors.forename: Asma
authors.initials: A
authors.lastname: Khalil
authors.affiliation: From the Fetal Maternal Medicine Unit, Department of Obstetrics and Gynaecology, St George's University of London, London, United Kingdom (K.M., A.K., B.T.); Department of Obstetrics and Gynecology, Santo Spirito Hospital, Pescara, Italy (K.M.); and Department of Cardiology and Cardiothoracic Surgery, St George's University of London, London, United Kingdom (R.S.). basky@pobox.com.
authors.forename: Baskaran
authors.initials: B
authors.lastname: Thilaganathan
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D016534:Cardiac Output, High / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D005865:Gestational Age; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology; D011247:Pregnancy / Q000502:physiology*; D011446:Prospective Studies; D012016:Reference Values; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D013318:Stroke Volume / Q000502:physiology*; D016216:Ultrasonography, Prenatal / Q000379:methods; D006113:United Kingdom; D014655:Vascular Resistance / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: LV hypertrophy; diastolic dysfunction; echocardiography; pregnancy; remodeling; tissue Doppler