Echocardiographic assessment of left atrial mechanics in women with hypertensive disorders of pregnancy: A systematic review and meta-analysis

Abstract

Objective: The influence of hypertensive disorders of pregnancy (HDP) on left atrial (LA) mechanics assessed by speckle tracking echocardiography (STE) has been poorly investigated. Accordingly, we performed a meta-analysis to summarize the main findings of STE studies who measured LA reservoir (LASr), conduit (LAScd) and contractile (LASct) strain in HDP women.

Study design: All echocardiographic studies assessing LA strain parameters in HDP women vs. healthy controls, selected from PubMed and EMBASE databases, were included. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment of Case-Control Studies. Continuous data (LASr, LAScd and LASct) were pooled as standardized mean difference (SMD) comparing HDP group with healthy controls. The overall SMDs of LASr, LAScd and LASct were calculated using the random-effect model.

Results: The full-texts of 8 studies with 566 HDP women and 420 healthy pregnant women were analyzed. Average LASr (34.3 ± 6.4 vs 42.7 ± 5.3 %, P = 0.01) and LAScd (23.4 ± 6.3 vs 32.5 ± 6.0 %, P < 0.001) were significantly lower in HDP women than controls, whereas LASct (-13.0 ± 5.4 vs -13.7 ± 4.5 %, P = 0.18) was similar in the two groups of women. Substantial heterogeneity was detected among the studies evaluating LASr (I² = 94.3 %), LAScd (I² = 64.9 %) and LASct (I² = 86.4 %). SMDs were large and statistically significant for LASr (-1.70, 95 %CI -2.34,-1.06, P < 0.001) and LAScd (-1.35, 95 %CI -1.69,-1.00, P < 0.001), small and not statistically significant for LASct (-0.11, 95 %CI -0.60,0.39, P = 0.678) assessment. Egger's test gave P-values of 0.10, 0.34 and 0.75 for LASr, LAScd and LASct measurement respectively, indicating no publication bias. On meta-regression analysis, none of the moderators was significantly associated with effect modification for LASr and its components (all P < 0.05).

Conclusions: HDPs are independently associated with LASr impairment in pregnancy. STE allows to identify, among HDP women, those who might benefit from a more aggressive antihypertensive treatment and/or a closer clinical follow-up, aimed at reducing the risk of adverse maternal outcome and cardiovascular complications later in life.

Keywords: Hypertensive disorders; Left atrial mechanics; Left atrial reservoir strain; Pregnancy; Subclinical myocardial dysfunction.