Physical activity, rather than prior preeclampsia, impacts cardiac hemodynamics after pregnancy

Background: Women with pregnancies complicated by preeclampsia have a higher risk for developing cardiovascular disease compared to women with normotensive pregnancies (1). This indicates persistent cardiovascular changes, although the underlying mechanisms are unclear. Kinetic energy and hemodynamic forces are emerging imaging biomarkers for cardiac function (2,3), but have not been studied in women with prior preeclampsia.

The aim of this study was to investigate left ventricular kinetic energy and hemodynamic forces in women 4–7 years after severe preeclampsia and compare those to women with normotensive pregnancies.

Methods: Women pregnant 4–7 years prior to the examination were recruited in three groups matched for time from delivery and age; 1) prior preeclampsia and admitted to the intensive care unit due to complications to severe preeclampsia (called Preeclampsia group), 2) normotensive pregnancy with a physical activity level matching the preeclampsia group (called Controls), and 3) normotensive pregnancy with a physical activity level above the WHO recommendations (called Active).

All participants underwent CMR with balanced steady-state free precession cine images in standard short- and long-axis views, and three-dimensional time-resolved phase-contrast flow (4D-flow research sequence) at 1.5 T (MAGNETOM Aera, Siemens Healthineers, Forchheim, Germany). Image analysis was performed in Segment v4.1.0.2 (Medviso, Lund, Sweden) (4). Endocardial borders were delineated in time-resolved short-axis stacks covering the entire left ventricular cavity. Left ventricular kinetic energy and hemodynamic forces were computed from the 4D-flow data. The Mann-Whitney U test was used for group comparisons using Prism v10.5.0 (Graphpad, Boston, Massachusetts, USA).

Results: There were no differences in left ventricular volumes or mass between the Preeclampsia group and Controls (Table 1). The Active group had larger end-diastolic, end-systolic, and stroke volumes compared to the Preeclampsia group, whereas left ventricular mass did not differ between groups.

Figure 1 shows kinetic energy and hemodynamic forces in the apex-base direction over the entire cardiac cycle for the three groups.

Figure 2 shows peak kinetic energy and hemodynamic forces for systole and diastole for the three groups. The Preeclampsia group had lower systolic peak kinetic energy and hemodynamic forces compared to the Active group, but no differences were seen in systole between Preeclampsia and Controls. In diastole, no differences were seen between groups.

Conclusion: Left ventricular kinetic energy and hemodynamic forces differ between women with prior severe preeclampsia compared to women with normotensive pregnancy with a physical activity level following the WHO recommendations, but not compared to controls with an activity level comparable to that of the women with prior preeclampsia. The results indicate that physical activity, rather than prior preeclampsia, impacts cardiac hemodynamics after pregnancy.

Participant characteristics and left ventricular volumes and mass by cardiac magnetic resonance imaging

	Preeclampsia (n=8)	Controls (n=9)	Active (n=9)	p-value  Controls	p-value Active
Age (years)	42 [35 – 48]	39 [37 – 43]	36 [34-42]	0.7	0.4
Time since index pregnancy (years)	6 [5 – 7]	6 [5 – 7]	5 [4 – 6]	1	0.1
Heart rate (bpm)	63 [60 – 71]	63 [59 – 71]	59 [52-62]	1	0.06
LVM (g)	73 [63-83]	78 [65-85]	81 [72-86]	0.7	0.1
EDV (mL)	148 [139 – 174]	160 [131 – 174]	181 [167-194]	0.7	0.02
ESV (mL)	57 [49 – 68]	60 [55 – 78]	73 [69-85]	0.5	0.02
SV (mL)	92 [86 – 95]	94 [76 – 96]	107 [97-117]	1	0.02
Cardiac output (L/min)	5.6 [5.0 – 6.3]	5.7 [4.8 – 6.4]	6.1 [5.3-7.1]	0.8	0.4
Ejection fraction (%)	61 [58 – 63]	57 [54 – 61]	59 [57-62]	0.2	0.4

Data are presented as median [IQR; interquartile range]. P-values for comparisons between the Preeclampsia group and Controls, or between the Preeclampsia group and Active. bpm, beats per minute; LVM, left ventricular mass; EDV, end-diastolic volume; ESV, end-systolic volume; SV, stroke volume.Kinetic energy (top) and hemodynamic forces in the apex-base direction (bottom) over the cardiac cycle in women with prior preeclampsia (left), controls (middle) and women following the WHO recommendations for physical activity (Active) (right). All three groups exhibit similar patterns in kinetic energy and forces, but the Active group shows higher systolic peaks.
Peak kinetic energy and hemodynamic forces in the apex-base direction in systole (top) and diastole (bottom) in women with prior preeclampsia, controls, and women following the WHO recommendations for physical activity (Active). In systole, both kinetic energy and forces exhibit patterns of increasing peaks from preeclampsia, to controls, to the active group.