Impact of Gestational Hypertension on Left Ventricular Function and Geometric Pattern

Transcription

1 Circulation Journal Official Journal of the Japanese Circulation Society ORIGINAL ARTICLE Hypertension and Circulatory Control Impact of Gestational Hypertension on Left Ventricular Function and Geometric Pattern Kyoung-Im Cho, MD; Seong-Man Kim, MD; Mi-Seung Shin, MD; Eui-Joo Kim, MD; Eun-Joo Cho, MD; Hae-Sun Seo, MD; Sung-Hee Shin, MD; Se-Jung Yoon, MD; Jung-Hyun Choi, MD Background: The effect of gestational hypertension on left ventricular (LV) function in previously normotensive young women has not been evaluated. Methods and Results: A total of 106 gestational hypertensive women (GHW, 32.3±4.2 years) and 93 normotensive pregnant women (NPW, 30.2±4.4 years) were enrolled. Transthoracic echocardiography, including 2-dimensional strain echocardiography, was done and myocardial performance (Tei index), LV mass index (LVMI), and relative wall thickness (RWT) were analyzed. GHW had significantly increased wall thickness (interventricular septum, 9.5±0.9 mm vs. 8.8±1.0 mm, P<0.001; posterior wall, 9.0±1.1 mm vs. 8.5±1.1 mm, P=0.007; and RWT, 0.39±0.06 vs. 0.35±0.05, P=0.02), higher LVMI (95.6±17.3 g/m 2 vs. 86.1±14.5 g/m 2, P=0.03), longer isovolumetric relaxation time (117.7±18.2 ms vs. 82.3±12.6 ms, P=0.003), lower E/A ratio (1.00±0.29 vs. 1.27±0.33, P=0.002), and higher Tei index (0.48±0.23 vs. 0.33±0.13, P=0.003) compared to NPW. Global longitudinal LV strain, representing LV systolic function, was also significantly reduced in GHW compared with NPW ( 17.6±2.95% vs. 21.2±2.14%, P=0.02). A total of 62% of GHW (n=66) had abnormal geometry, of whom, 42 (40%) had eccentric hypertrophy (EH). A total of 93% of NPW (n=86) had normal geometry, and only 7 NPW (7%) had abnormal geometry. Conclusions: GHW had aggravated diastolic and longitudinal systolic dysfunction. GHW had increased LVMI with the abnormal geometric pattern of EH. The reversibility of these morphological and functional impairments after delivery needs to be clarified. (Circ J 2011; 75: ) Key Words: Hypertension; Left ventricular function; Pregnancy The development of left ventricular (LV) hypertrophy in essential hypertension is associated with an increase of LV afterload and severity and duration of the disease process. 1 3 Patients with essential hypertension are exposed to long-lasting pressure overload with enough time for development of pathologic changes in LV structure and function. The morphologic and functional LV changes induced by essential hypertension are well known. 4 Gestational hypertension (GH) is a systemic hypertension that develops during gestation in young women with previously normotensive hearts. Estimation of diastolic dysfunction is usually based on conventional indices that represent the global status. 5 An easily measured Doppler index of myocardial performance, however, combining systolic and diastolic time intervals, has been reported to be simple, reproducible, and independent of heart rate and blood pressure (BP). 6 Moreover, altered segmental contraction based on strain echocardiography may be a sensitive method to evaluate the changes in LV function in GH because it is evident before global conventional indices of systolic dysfunction become definitely informative. 7 Editorial p 1055 In the present study we measured and compared LV structure and function in normotensive pregnant women (NPW) with those in patients with GH. The purpose of the present study was to assess the impact of GH on the systolic and diastolic performance and structure of the left ventricle in the previously normotensive young heart. Received August 2, 2010; revised manuscript received November 30, 2010; accepted December 27, 2010; released online March 7, 2011 Time for primary review: 22 days Division of Cardiology, Maryknoll Medical Center, Busan (K.-I.C., S.-M.K.); Division of Cardiology, Gachon University, Gil Hospital, Incheon (M.-S.S., E.-J.K.); Division of Cardiology, College of Medicine, Inha University, Incheon (S.-H.S.); Division of Cardiology, Catholic University, St Paul s Hospital, Seoul (E.-J.C.); Division of Cardiology, Soonchunhyang University, Bucheon (H.-S.S.); Division of Cardiology, NHIC Ilsan Hospital, Ilsan (S.-J.Y.); and Division of Cardiology, Dankook University, Chunahan (J.-H.C.), Korea Mailing address: Mi-Seung Shin, MD, Division of Cardiology, Gachon University, Gil Hospital, 1198, Guwol-dong, Namdong-gu, Incheon, , Korea. miseung@gmail.com ISSN doi: /circj.CJ All rights are reserved to the Japanese Circulation Society. For permissions, please cj@j-circ.or.jp

2 Gestational Hypertension and LV Function 1171 Table 1. Patient Characteristics Parameters GHW (n=106) NPW (n=93) P value Age (years) 32.3± ±4.4 <0.001 Weight (kg) 75.0± ± Weight gain (kg) 15.7± ± Height (cm) 159.2± ± Body mass index (kg/m 2 ) 27.5± ± Gestation (weeks) 33.3± ±3.4 <0.001 Systolic BP (mmhg) 152.6± ±13.0 <0.001 Diastolic BP (mmhg) 94.9± ±11.1 <0.001 Hemoglobin (mg/dl) 11.5± ± LVH on EKG 29/106 (27%) 8/93 (9%) <0.001 Drug history None None 1.0 GHW, women with gestational hypertension; NPW, normotensive pregnant women; BP, blood pressure; LVH, left ventricular hypertrophy; EKG, electrocardiography. Methods Subjects The present study was a multicenter study of the geometrical and functional changes in patients with GH. The study protocol was approved by the Institutional Review Board of all participating institutions and all patients provided written informed consent. We studied 106 women (mean age, 32.3±4.2 years) who were diagnosed with GH between January 2008 and April 2010 at 7 institutions (mean pregnancy duration, 33.3±3.6 weeks) in South Korea. Women with GH (GHW) were diagnosed when systolic or diastolic pressures were >140/90 mmhg without proteinuria in a resting and sitting position on at least 2 occasions after 20 weeks of gestation. 8 None of the women had previous recordings or a history of hypertension, and BP during the first and second trimesters of the pregnancy was normal. All patients had standard 12- lead electrocardiography (ECG) recorded at 25 mm/s and 1 mv/cm. LV hypertrophy on ECG was defined according to the traditional Sokolow Lyon voltage criteria (SV1 + RV5 or RV6 3.5 mv). These measurements were compared to those obtained in 93 NPW (mean age, 30.2±4.4 years, mean pregnancy duration, 35.1±3.4 weeks). Patients with diabetes mellitus, essential hypertension or symptomatic coronary artery disease were excluded. Of the 106 women given the diagnosis of GH, 37 underwent follow-up echocardiography after delivery for evaluation of the changes. Echocardiography Standard 2-dimensional (D) and strain echocardiography were performed on all subjects while lying in the left lateral decubitus position using a 3.5-MHz transducer (Vivid 7 Dimension ultrasound equipment, General Electric, Horten, Norway) and the echocardiography examiners were blinded to patient information. Each center used the same echocardiogram equipment to avoid bias of examination and analysis of parameters. Standard and Doppler Echocardiography Measurements of the thickness of interventricular septum and posterior wall, and the diameter of LV cavity were performed according to the American Society of Echocardiography (ASE) criteria. 9 LV mass was calculated using the corrected American Society of echocardiography cube formula 10 and indexed for body surface area to obtain the LV mass index (LVMI). The relative wall thickness (RWT) was measured at end diastole as the ratio between double posterior wall thickness to the LV diastolic cavity diameter. The LV geometries were classified into 4 groups based on LVMI and RWT as the following: 3 normal geometry, if LVMI and RWT were less than the mean ± 2SD of those corresponding to NPW; concentric hypertrophy (CH), if both LMMI and RWT were increased; eccentric hypertrophy (EH), if LVMI was increased and RWT was normal; and concentric remodeling (CR), if LVMI was normal and RWT was increased. Pulsed wave Doppler of the transmitral LV inflow was performed in the apical 4-chamber view with the sample volume placed at the level of the mitral valve tips, and Doppler variables were analyzed during 3 consecutive beats. The following measurements of global LV diastolic function were determined: peak early (E) and late (A) diastolic mitral flow velocity and their ratio E/A, early (Ea) diastolic mitral annular velocity, deceleration time of the E wave, and LV isovolumetric relaxation time (IVRT). Doppler time intervals were measured from mitral inflow and LV outflow velocity time intervals as described by Tei et al, 7 and the index of combined LV systolic and diastolic function (the sum of isovolumetric contraction time [ICT] and IVRT divided by ejection time) was calculated. Strain Echocardiography 2-D grayscale images (frame rate 70/s) were obtained in the apical 2-chamber, 3-chamber, and 4-chamber views using a narrow sector angle. Images from LV apical chamber views were obtained at end-expiratory apnea and were stored in cineloop format for subsequent offline analysis. Three heartbeats were collected from each view and 1 selected cycle was analyzed off-line with an EchoPAC Dimension system (General Electric). Peak systolic strain was measured and averaged to assess global longitudinal myocardial regional function (GLS). The endocardial borders were traced at the end-systolic frame, and an automated tracking algorithm outlined the myocardium in successive frames throughout the cardiac cycle. The tracking quality was verified for each segment (with subsequent manual adjustment of the region of interest if necessary), and myocardial motion was analyzed using speckle tracking within the region of interest bound by endocardial and epicardial borders. Inadequate tracked segments were automatically excluded from analysis. In this situation, local strain in each segment was calculated. GLS was obtained by averaging all segment strain values from the apical 4-chamber, 2-chamber, and long axis views.

3 1172 CHO KI et al. Table 2. M-Mode Assessment of LV Geometry Parameters GHW (n=106) NPW (n=93) P value LVEDD (mm) 50.0± ± LVESD (mm) 32.4± ± IVSTd (mm) 9.5± ±1.0 <0.001 PWTd (mm) 9.0± ± RWT 0.39± ± LVMI (g/m 2 ) 95.6± ± LAD (mm) 38.6± ± ARD (mm) 29.6± ± LV, left ventricular; LVEDD, left ventricular end diastolic dimension; LVESD, left ventricular end systolic dimension; IVSTd, interventricular septal thickness; PWTd, left ventricular posterior wall thickness; RWT, relative wall thickness; LVMI, left ventricular mass index; LAD, left atrial dimension; ARD, aortic root dimension. Other abbreviations see in Table 1. Figure 1. Geometric pattern of ventricular hypertrophy in hypertensive pregnant women: cut-off at mean ± 2SD of normotensive pregnant women (NPW). CH, concentric hypertrophy; CR, concentric remodeling; EH, eccentric hypertrophy; GHW, women with gestational hypertension. Table 3. LV Function in GHW and NPW Parameters GHW (n=106) NPW (n=93) P value EF (%) 62.3± ± FS (%) 33.8± ± DT (ms) 171.9± ± E (cm/s) 79.5± ± E/Ea 11.7± ± A (cm/s) 75.4± ±14.3 <0.001 E/A 1.00± ± IVRT (ms) 117.7± ± Tei index 0.51± ± Global LV strain (%) 17.6± ± EF, ejection fraction; FS, fractional shortening; DT, deceleration time; E, peak E velocity; Ea, peak early diastolic annular velocity; A, peak A velocity; IVRT, isovolumetric relaxation time. Other abbreviations see in Tables 1,2. Figure 2. Regression analysis between parameters of left ventricular (LV) geometry and myocardial performance index (Tei index) in gestational hypertension. (A) LV mass index had no significant effect on Tei index, but (B) relative wall thickness and (C) weeks of gestation had significant effects on Tei index.

4 Gestational Hypertension and LV Function 1173 Statistical Analysis Data were analyzed using standard statistical software (SPSS 12, SPSS, Chicago, IL, USA). Continuous variables, expressed as mean ± SD, were compared using Student s t-test for independent groups. Linear regression was used to investigate the relation between 2 parametric variables. P<0.05 for a 2-tailed test was considered significant. Results Baseline Patient Characteristics General and clinical details of the study groups are summarized in Table 1. Although it was intended to having matching age and pregnancy duration between the groups, the GHW were slightly older and had shorter pregnancy duration. Systolic and diastolic BP, weight, weight gain during pregnancy, and body mass index were significantly higher in GHW compared to NPW. There were no significant differences in height and hemoglobin level in both groups. Ventricular Geometric Patterns There were no significant differences in left atrial dimension, LV dimension, and aortic dimension. The interventricular septal thickness, posterior wall thickness, LVMI, and RWT, however, were significantly higher in GHW (Table 2). According to the data, we considered the mean ± 2SD as the upper normal limit for LVMI and RWT in NPW, and these were g/m 2 for LVMI and 0.45 for RWT. There were 40 women (38%) with normal geometry, 42 (40%) with EH, 18 (17%) with CR, and 6 (5%) with CH in the GHW group. The geometric patterns in the NPW, however, were normal geometry in 86 (93%) and EH in 7 (7%; Figure 1). Ventricular Functional Changes The LV global systolic function, as expressed by ejection fraction and fractional shortening, was similar between GHW and NPW. Although there was no significant difference in peak E velocity in both groups, peak A velocity was significantly higher in GHW than in NPW, and E/A ratio was significantly lower in GHW. The IVRT, E/Ea and Tei index were significantly higher in GHW (Table 3). RWT and duration of pregnancy both had a significant positive effect on Tei index in GHW (Figures 2B,C). LVMI, however, had no significant effect on Tei index (Figure 2A), nor did age. Global longitudinal LV strain was also significantly reduced in GHW compared with NPW ( 17.6±2.95% vs. 21.2±2.14%, P=0.02). LVMI, RWT, and systolic BP (SBP) had a significant negative effect on global longitudinal LV strain in GHW (Figure 3). Moreover, global LV strain in GHW was significantly lower in patients with the abnormal geometry of EH ( 16.4±3.5%), CR ( 15.6±4.2%) and CH ( 14.3±3.9%) compared with the normal geometry group ( 20.9±3.2%; all P<0.05). Figure 3. Regression analysis between parameters of left ventricular (LV) geometry and global LV strain in gestational hypertension. (A) LV mass index, (B) relative wall thickness, and (C) systolic blood pressure had significant effects on global longitudinal LV strain. Clinical Course and Follow-up Echocardiography Of the 106 GHW, 37 underwent follow-up echocardiography after 6 months for evaluation of geometric and functional changes of LV. Ten of 37 GHW progressed to pre-eclampsia according to the development of proteinuria between 27 and 35 gestational weeks, and 5 pre-eclampsia patients developed peripartum cardiomyopathy around the end of pregnancy or in the months following delivery with reduced LV ejection fraction below 45%. Eight pre-eclampsia patients (including 3 who developed peripartum cardiomyopathy) returned to normal within 3 months of delivery and follow-up echocardiogram was normal. Twenty-two who had transient hypertension returned to normal BP within 3 months of delivery, and follow-up echocardiogram showed normal LV geometry and Tei index. Seven progressed to chronic hypertension and had persistent high BP after 6 months of delivery, and follow-up echocardiography showed abnormal geometry and high Tei

5 1174 CHO KI et al. Table 4. Follow-up Echocardiography and Clinical Features Parameters GHW before delivery (n=37) GHW after delivery (n=37) P value Systolic BP (mmhg) 155.5± ±15.6 <0.001 Diastolic BP (mmhg) 96.8± ±14.3 <0.001 Weight (kg) 75.5± ±14.5 <0.001 LVEDD (mm) 50.2± ± LVESD (mm) 34.9± ± IVSTd (mm) 9.4± ± PWTd (mm) 9.0± ± RWT 0.40± ± LVMI (g/m 2 ) 95.8± ± LAD (mm) 39.1± ± ARD (mm) 29.4± ± EF (%) 58.3± ± FS (%) 33.6± ± DT (ms) 178.8± ± E (cm/s) 81.7± ± E/Ea 12.7± ± A (cm/s) 76.3± ± E/A 1.08± ± IVRT (ms) 118.8± ± Tei index 0.53± ± Global LV strain (%) 17.3± ± Abbreviations see in Tables 1 3. index (mean, 0.50±0.1; Table 4). Interestingly, most of the patients who progressed to pre-eclampsia had abnormal LV geometry and function (2 [20%], EH; 4 [40%], CR; 1 [10%], CH), and all of the 5 pre-eclampsia patients who developed peripartum cardiomyopathy had abnormal geometry (2 [40%], EH; 3 [60%], CR). The GHW who returned to normal BP after delivery, however, had normal geometry; and the RWT and the Tei index were comparable to those of 15 NPW after delivery on follow-up echocardiography after 6 months (RWT: 0.36±0.09 in GHW after delivery vs. 0.34±0.06 in NPW after delivery, P=NS; Tei index: 0.42±0.18 in GHW after delivery vs. 0.39±0.06 in NPW after delivery, P=NS). Discussion During normal pregnancy, stroke volumes and heart rate increase and peripheral resistance decreases. In women with GH, however, peripheral resistance increases, whereas plasma and cardiac volumes may remain normal or even decrease. 8 These changes produce a pressure overload on the left ventricle and normalize rapidly after delivery. Regarding LV structural change in GHW, previous studies differed in several areas. Sanchez et al and Thompson et al did not find any significant changes in LV mass, 11,12 whereas Vazquez Blanco et al 13 found that LV mass and RWT increased and the LV geometric pattern was modified in GHW. Recently, Vlahović-Stipac et al reported that there was an increase in wall thickness from baseline to second measurement, with consequential increase in LV mass in GHW without significant changes in LV volumes. 14 According to the present study, GHW had a significant increase in LV mass, a situation that especially reflects an increase in septal and posterior wall thickness without changes in LV diastolic diameter, and these findings were confirmed by our previous study. 15 We considered the mean ± 2SD of LVMI and RWT of NPW as the upper limit of normal for the NPW group (115.1 g/m 2 and 0.45, respectively), and these results differ from those reported by Ganau et al, who obtained 106 g/m 2 and 0.44, respectively. 3 Also, the normal upper limit for LV mass was different from the Soh et al and the Park reports (100.5 g/m 2, g/m 2, respectively) in Korean subjects. 16,17 These differing results may be due to differences in the subjects in terms of age and the duration of pregnancy. The pregnant women in the present study had other hemodynamic modifications that can produce different changes in the structure and function of the left ventricle. In contrast to essential hypertension, GH affects the previously healthy cardiovascular system of young women. The duration of pressure overload to the heart is <10 months in this condition. Furthermore, pregnancy imposes a volume overload on the circulatory system also. In the non-pregnant state it is well known that obesity is a risk factor for the development of hypertension, and overweight women are more prone to develop GH. 18 In the present study, weight gain during pregnancy and body mass index were significantly higher in GHW compared to NPW, implicating volume overload. Moreover, GHW had higher E/Ea than NPW, which has been shown to correlate with invasive measures of LV filling pressure. 19 The combined pressure and volume overload explain the tendency toward EH in GH, as shown in the present study. This pattern of EH (cavity dilatation with a decrease in the ratio of wall thickness/chamber dimension) is initially compensatory, such that the heart can meet the demand to sustain a high stroke volume and also a form of LV failure due to pressure overload. 20,21 In the present study, no patient had overt cardiac failure, although we cannot rule out the possibility that this type of geometric remodeling may hide a latent form of contractile failure, suggested by lower myocardial performance index and global longitudinal deformation parameters. The present study showed that the geometric pattern CR was prevalent in GHW who progressed to pre-eclampsia, and is consistent with the mechanism suggested by Ganau et al, 3 who proposed that the increase in peripheral resistance with a decrease in preload is caused by a contraction of the intravascular volume. Moreover, nearly all pre-eclampsia patients with EH or CR eventually developed peripartum cardiomyopathy, indicating that geometric remodeling might be a predisposing factor to peripartum cardiomyopathy. CH is the type of geometric pattern expected in those patients with an increase in afterload. 20,21 The number of women with CH was lower in the present study, however, and this may be explained by the fact that GH is a short-lasting phenomenon. A considerable number of essential hypertensive patients, even those with a relatively prolonged form of the disease, and GHW had a normal geometric pattern. It may be possible that other issues, such as the contractile state of the myocardium and even genetic causes, can explain the lack of structural changes seen in patients with essential hypertension, as well as in GHW. Studies related to myocardial function in GH are scant and also controversial. 22,23 Discrepancies in the findings related to diastolic function are evident even in normal pregnant women, given that some investigators highlight significant changes in diastolic function whereas others fail to prove them, 22 but there is agreement in the literature on the alteration in the diastolic function in GH. Vazquez Blanco et al concluded that the E/A ratio tended to be lower in GH but that the E velocity did not change. 23 The A velocity was higher, however, and

6 Gestational Hypertension and LV Function 1175 the IVRT markedly increased in this group of patients, and these findings were consistent with the present results. A Doppler index introduced by Tei et al, consisting of the sum of the IVRT and ICT, divided by the ejection time, includes the duration of systolic and diastolic time intervals to globally evaluate myocardial performance. 7 The IVRT and the ICT are prolonged, whereas the ejection time tends to be shorter in cardiac disease. 24 Thus, the index has the potential to unmask lesser degrees of LV myocardial dysfunction. Concerning hypertension, there is a report that the Tei index increased significantly in patients with CR or CH, irrespective of systolic function compared to normal subjects. 7 We found that the Tei index was significantly correlated to the RWT; also in GHW the RWT was increased, and one of the more frequent LV geometric patterns was EH. Therefore, the alteration of the index is expected in this group of patients. In the present study, GHW were found to have more deteriorated longitudinal systolic function based on global LV strain and higher E/Ea compared to normal pregnant women, despite the normal global systolic function measured by ejection fraction. Global LV strain was also correlated with structural changes of LV remodeling (RWT and LVMI) and with SBP. The longitudinal peak systolic strain and strain rate have been shown to be linearly correlated with the maximum of the LV filling pressure time derivative and also with the peak elastance, which are both global measures of LV systolic function and contractility. 25 The 2-D strain measurement, as determined by speckle tracking, has recently been used for the quantitative evaluation of LV function, and this method has been validated for the evaluation of longitudinal LV function. 26,27 Subclinical LV dysfunction relates to the structure function relationship and characterizes a preclinical stage of myocardial damage caused by microvascular ischemia and fibrosis, which is common in systemic hypertension. Therefore, subclinical LV dysfunction can be detected by a decrease in longitudinal myocardial function, which occurs before the development of abnormality in conventional measures of LV performance. 28 This evidence explains the finding of longitudinal functional deterioration as a result of early subendocardial lesions in GH patients; and the present findings regarding the presence of longitudinal dysfunction are consistent with other studies that have shown the progressive nature of longitudinal deterioration in patients with diastolic heart failure, even in patients with transient hypertension, 29 indicating that reduced global myocardial performance of the left ventricle would be one of the useful indices for quantitative assessment in high-risk pregnancies. 30 The present study shows that the BP of GHW decreased after delivery, as happens usually, and that RWT and Tei index returned to normal but remained higher compared to NPW at the time of follow-up echocardiography. Pregnancy followed by delivery may decrease arterial stiffness. 31 The present results, however, suggest that the structural and functional changes produced by this transient pressure overload persist even after BP normalizes. To the best of our knowledge, the present investigation is the first to evaluate ventricular geometry and function using the Tei index and strain parameters in a relatively large number of GHW (>100 subjects). Although the normal geometric pattern is showed in 38% of GHW, this short-lasting pressure overload is capable of inducing changes in the structure of the left ventricle. The dimensions of the left ventricle, the left atrium, and the aortic root, however, did not change, indicating that GH does not have enough time to produce morphologic changes in the left atrium and the aortic root. The present study confirms that the Tei index of global myocardial performance and longitudinal deformation parameters are altered in GHW, being the most powerful parameters to unmask ventricular functional impairment. Although a small number of the study subjects (37/102) were followed up, 81% (30/37) of GHW returned to normal within 3 months of delivery, and follow-up echocardiogram was normal. Nearly all pre-eclampsia patients with EH or CR, however, eventually developed peripartum cardiomyopathy, indicating that geometric remodeling might be a predisposing factor to peripartum cardiomyopathy. The present study had several limitations. Although we observed the reversal of geometrical and functional impairment after delivery, only 30% of GPW were followed up, therefore the reversibility of morphological and functional impairment after delivery needs to be clarified. The present study was not designed to examine the difference between gestational and non-gh. Other studies, however, have shown that essential hypertension is characterized by a compensatory late filling mechanism due to an enhancement of left atrial function, and that GH is characterized by altered LV geometry (which is far less common during essential hypertension 32 ), which was observed in the present study. Conclusion GH is a condition of combined pressure and volume overload, within a relatively short period, in a previously young and healthy heart compared with essential hypertension. Aggravated diastolic dysfunction with a high prevalence (62%) of abnormal geometric pattern (the most common form being EH) and a decrease in longitudinal systolic contractility, as well as in global cardiac performance, are the main features of GH. Reversibility of these morphological and functional changes should be observed after delivery. References 1. Levy D, Larson MG, Vasan RS, Kannel WB, Ho KK. The progression from hypertension to congestive heart failure. JAMA 1996; 275: Strauer BE. Structural and functional adaptation of the chronically overloaded heart in arterial hypertension. Am Heart J 1987; 114: Ganau A, Devereux RB, Roman MJ, de Simone G, Pickering TG, Saba PS, et al. Patterns of left ventricular hypertrophy and geometric remodeling in essential hypertension. J Am Coll Cardiol 1992; 19: Aeschbacher BC, Hutter D, Fuhrer J, Weidmann P, Delacredaz E, Allemann Y. Diastolic dysfunction precedes myocardial hypertrophy in the development of hypertension. Am J Hypertens 2001; 14: Inouye I, Massie B, Loge D, Topic N, Silverstein D, Simpson P, et al. Abnormal left ventricular filling: An early finding in mild to moderate systemic hypertension. Am J Cardiol 1984; 53: Takemoto Y, Pellikka PA, Wang J, Modesto KM, Cauduro S, Belohlavek M, et al. Analysis of the interaction between segmental relaxation patterns and global diastolic function by strain echocardiography. J Am Soc Echocardiogr 2005; 18: Tei C, Ling LH, Hodge DO, Bailey KR, Oh JK, Rodeheffer RJ, et al. New index of combined systolic and diastolic myocardial performance: A simple and reproducible measure of cardiac function a study in normal and dilated cardiomyopathy. J Cardiol 1995; 26: Report of the National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy. Am J Obstet Gynecol 2000; 183: S1 S Levy D, Savage DD, Garrison RJ, Anderson KM, Kannel WB, Castelli WP. Echocardiographic criteria for left ventricular hypertrophy. Am J Cardiol 1987; 59: Devereux RB, Alonso DR, Lutas EM, Gottlieb GJ, Campo E, Sachs I, et al. Echocardiographic assessment of left ventricular hypertro-

7 1176 CHO KI et al. phy: Comparison with necropsy findings. Am J Cardiol 1986; 57: Sanchez RA, Glenny JE, Marco E, Voto LS, Lapidus AM, Iglesias GH, et al. Two-dimensional and M-mode echocardiographic findings in hypertensive pregnant women. Am J Obstet Gynecol 1986; 154: Thompson JA, Hays PM, Sagar KB, Cruikshank DP. Echocardiographic left ventricular mass to differentiate chronic hypertension from preeclampsia during pregnancy. Am J Obstet Gynecol 1986; 155: Vazquez Blanco M, Grosso O, Bellido C, Iavicoli OR, Berensztein CS, Vega HR, et al. Left ventricular geometry in pregnancy-induced hypertension. Am J Hypertens 2000; 13: Vlahović-Stipac A, Stankić V, Popović ZB, Putniković B, Nesković AN. Left ventricular function in gestational hypertension: Serial echocardiographic study. Am J Hypertens 2010; 23: Cho KI, Kim DS, Kim TI, Park JH, Kim SM, Kim DK, et al. Echocardiographic assessment of LV geometric pattern and function in pregnancy-induced hypertension. Korean Circ J 2005; 35: Soh JB, Son SS, Kim SH, Jeong JW, Park YK, Park OK. Relation of left ventricular mass to body size and left ventricular wall stress in normal adults. Korean Circ J 1996; 26: Park SW. Multicenter trial of estimation of normal values of echocardiographic indices in Korea. Korean Circ J 2000; 30: Martin A, O Sullivan AJ, Brown MA. Body composition and energy metabolism in normotensive and hypertensive pregnancy. BJOG 2001; 108: Ommen SR, Nishimura RA, Appleton CP, Miller FA, Oh JK, Redfield MM, et al. Clinical utility of Doppler echocardiography and tissue Doppler imaging in the estimation of left ventricular filling pressures: A comparative simultaneous Doppler-catheterisation study. Circulation 2000; 102: Devereux RB, de Simone G, Ganau A, Roman MJ. Left ventricular hypertrophy and geometric remodeling in hypertension: Stimuli, functional consequences and prognostic implication. J Hypertens Suppl 1994; 12: S117 S Hamond IW, Devereux RB, Alderman MH, Laragh JH. Relation of blood pressure and body build to left ventricular mass in normotensive and hypertensive employed adults. J Am Coll Cardiol 1988; 12: Kane A, Ba SA, Sarr M, Diop IB, Hane L, Faye MC, et al. Echocardiographic parameters in normal pregnant women. Ann Cardiol Angeiol (Paris) 1997; 46: Vazquez Blanco M, Roisinblit J, Grosso O, Rodriguez G, Robert S, Berensztein CS, et al. Left ventricular function impairment in pregnancy-induced hypertension. Am J Hypertens 2001; 14: Grossman W, McLaurin LP, Rolett EL. Alterations in left ventricular relaxation and diastolic compliance in congestive cardiomyopathy. Cardiovasc Res 1979; 13: Matsuda Y, Toma Y, Matsuzaki M, Moritani K, Satoh A, Shiomi K, et al. Change of left atrial systolic pressure waveform in relation to left ventricular end-diastolic pressure. Circulation 1990; 82: Marwick TH. Measurement of strain and strain rate by echocardiography: Ready for prime time? J Am Coll Cardiol 2006; 47: Becker M, Bilke E, Kuhl H, Katoh M, Kramann R, Franke A, et al. Analysis of myocardial deformation based on pixel tracking in two dimensional echocardiographic images enables quantitative assessment of regional left ventricular function. Heart 2006; 92: Chan J, Hanekom L, Wong C, Leano R, Cho GY, Marwick TH. Differentiation of subendocardial and transmural infarction using two-dimensional strain rate imaging to assess short-axis and longaxis myocardial function. J Am Coll Cardiol 2006; 48: Alam M, Hoglund C, Thorstrand C. Longitudinal systolic shortening of the left ventricle: An echocardiographic study in subjects with and without preserved global function. Clin Physiol 1992; 12: Watanabe S, Hashimoto I, Saito K, Watanabe K, Hirono K, Uese K, et al. Characterization of ventricular myocardial performance in the fetus by tissue Doppler imaging. Circ J 2009; 73: Hashimoto M, Miyamoto Y, Iwai C, Matsuda Y, Hiraoka E, Kanazawa K, et al. Delivery may affect arterial elasticity in women. Circ J 2009; 73: Novelli GP, Valensise H, Vasapollo B, Larciprete G, Di Pierro G, Altomare F, et al. Are gestational and essential hypertension similar? Left ventricular geometry and diastolic function. Hypertens Pregnancy 2003; 22: