Variations in Cardiovascular Structure, Function, and Geometry in Midlife Associated With a History of Hypertensive Pregnancy

Abstract

Hypertensive pregnancy is associated with increased maternal cardiovascular risk in later life. A range of cardiovascular adaptations after pregnancy have been reported to partly explain this risk. We used multimodality imaging to identify whether, by midlife, any pregnancy-associated phenotypes were still identifiable and to what extent they could be explained by blood pressure. Participants were identified by review of hospital maternity records 5 to 10 years after pregnancy and invited to a single visit for detailed cardiovascular imaging phenotyping. One hundred seventy-three women (age, 42±5 years, 70 after normotensive and 103 after hypertensive pregnancy) underwent magnetic resonance imaging of the heart and aorta, echocardiography, and vascular assessment, including capillaroscopy. Women with a history of hypertensive pregnancy had a distinct cardiac geometry with higher left ventricular mass index (49.9±7.1 versus 46.0±6.5 g/m²; P=0.001) and ejection fraction (65.6±5.4% versus 63.7±4.3%; P=0.03) but lower global longitudinal strain (-18.31±4.46% versus -19.94±3.59%; P=0.02). Left atrial volume index was also increased (40.4±9.2 versus 37.3±7.3 mL/m²; P=0.03) and E:A reduced (1.34±0.35 versus 1.52±0.45; P=0.003). Aortic compliance (0.240±0.053 versus 0.258±0.063; P=0.046) and functional capillary density (105.4±23.0 versus 115.2±20.9 capillaries/mm²; P=0.01) were reduced. Only differences in functional capillary density, left ventricular mass, and atrial volume indices remained after adjustment for blood pressure (P<0.01, P=0.01, and P=0.04, respectively). Differences in cardiac structure and geometry, as well as microvascular rarefaction, are evident in midlife after a hypertensive pregnancy, independent of blood pressure. To what extent these phenotypic patterns contribute to cardiovascular disease progression or provide additional measures to improve risk stratification requires further study.

Keywords: blood pressure; echocardiography; hypertension; magnetic resonance imaging; pre-eclampsia; pregnancy; women.

Figure 1.

Variation in left ventricular mass and capillary density in midlife related to severity of hypertensive pregnancy. A, Represents left ventricular (LV) mass index in women with a history of normotensive pregnancy (NTN—45.9 g/m²) compared with women with a history of different hypertensive disorders during pregnancy: gestational hypertension (GH—51.4 g/m²; P<0.01), late onset preeclampsia (PET) (late PET—49.6 g/m²; P=0.01), and early onset preeclampsia (early PET—49.4 g/m², P=0.02). B, Represents functional capillary density in women with a history of normotensive pregnancy (NTN—115 cap/mm²) compared with women with a history of different hypertensive disorders during pregnancy: (GH—103 cap/mm²; P<0.01), late onset preeclampsia (late PET—102 cap/mm², P<0.01), and early onset preeclampsia (early PET—111 cap/mm²; P=0.40).

Figure 2.

Major patterns of variation in left ventricular geometry in women in midlife and identification of those related to hypertensive pregnancy. A, Average anatomy (ie, atlas) of the 153 cases under study—2 views of the same 3-dimensional model in dark blue with a red sphere indicating the location of the right ventricle, and a thickness map (thickness colour map consistent throughout this figure). B, Cumulative variance explained by each mode of variation—mode 6 accounts only for the 1.7% of the variance in shape. C, Comparison of differences in shape between hypertensive and normotensive groups in the 20 first modes of variation (P value of unpaired T-test). D, The first 6 independent modes of variation. In all 6 cases, box-plots represent the hypertensive (green) and normotensive (blue) distributions in each model, with the average at coordinate 0 and is represented by a dark blue cross. In the 3-dimensional models, the average is again the dark blue left ventricular (LV) mesh overlaid on the orange and purple meshes. The orange cross and orange LV mesh represent −3 SD for each mode of variation; the purple cross and purple LV mesh, +3 SD for each mode of variation. As illustrated here, the modes of variation represent changes in the following: 1=ventricular length; 2=ventricular length linked to apex shift in the right to left direction and wall thickness; 3=apex shift in the right to left direction, linked to a milder wall thickness change; 4=wall thickness linked to diameter changes; 5=wall thickness with a proportion of apex position; and 6=wall thickness.