Echocardiographic Assessment of LV Geometric Pattern and Function in Pregnancy-Induced Hypertension

ABSTRACT

BACKGROUND AND OBJECTIVES: Chronic hypertension induces changes in the cardiac structure and function; however, the effects of transient hypertension are unclear. Pregnancy-induced hypertension (PIH) offers a natural and spontaneous model of this condition. SUBJECTS AND METHODS: 20 women, aged 30.3+/-5.1 years, with pregnancy-induced hypertension, defined as a blood pressure higher than 140/90 mmHg in the third trimester of pregnancy, with no prior history of hypertension, were studied. 20 normal pregnant women (NPW), aged 30.9+/-3.7 years, were used as the controls. The cardiac chamber dimensions, interventricular septal thickness (IVST), posterior wall thickness (PWT), left ventricular mass index (LVMI), relative wall thickness (RWT), E velocity, A velocity, E/A ratio, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), ejection time (ET) and the combined index of myocardial performance (Tei index=IRT+ICT/ET) were calculated by echocardiography. Subjects were considered to have normal geometry (NG) if both the LVMI and RWT were normal; concentric hypertrophy (CH) if both were elevated; eccentric hypertrophy (EH) if the LVMI was elevated and the RWT normal; and concentric remodeling (CR) if the LVMI was normal and the RWT elevated. RESULTS: There were significant differences between the 2 groups in the following parameters; IVST 10.5+/-1.3 mm in PIH vs. 8.6+/-1.0 mm in NPW (p<0.0001), PWT 10.0+/-1.4 mm in PIH vs. 8.9+/-0.9 mm in NPW (p<0.005), LVMI 113.1+/-20.3 g/m2 in PIH vs. 85.9+/-14.5 g/m2 in NPW (p<0.0001), RWT 0.41+/-0.08 in PIH vs. 0.35+/-0.03 in NPW (p<0.005), E/A ratio 0.95+/-0.29 in PIH vs. 1.56+/-0.27 in NPW (p<0.0001), IRT 118.8+/-19.5 msec in PIH vs. 83.1+/-12.4 msec in NPW (p<0.0001) and the Tei index 0.51+/-0.09 in PIH vs. 0.31+/-0.06 in NPW (p<0.0001). The geometric patterns of PIH women were NG in 4 (20%) and abnormal geometry in 16 (80%), of which 10 (50%) had EH. The geometric patterns of NPW were NG in 19 (95%) and abnormal geometry in 1 (5%), which also had EH. CONCLUSION: PIH increases the LVMI due to an increase in the IVST and PWT; the most frequent abnormal geometric pattern was EH. The dimensions of the left ventricle, left atrium and aortic root were unchanged. PIH showed left ventricular dysfunction, mainly diastolic. The IRT and Tei index are the most useful echocardiographic parameters to reveal left ventricular dysfunction in PIH.