Risk of venous thromboembolism in Chinese pregnant women: Hong Kong venous thromboembolism study

BACKGROUND: Previous Caucasian studies have described venous thromboembolism in pregnancy; however, little is known about its incidence during pregnancy and early postpartum period in the Chinese population. We investigated the risk of venous thromboembolism in a “real-world” cohort of pregnant Chinese women with no prior history of venous thromboembolism. METHODS: In this observational study, 15,325 pregnancies were identified in 14,162 Chinese women at Queen Mary Hospital, Hong Kong between January 2004 and September 2016. Demographic data, obstetric information, and laboratory and imaging data were retrieved and reviewed. RESULTS: The mean age at pregnancy was 32.4±5.3 years, and the median age was 33 years (interquartile range, 29–36 yr). Pre-existing or newly diagnosed diabetes mellitus was present in 627 women (4.1%); 359 (0.7%) women had pre-existing or newly detected hypertension. There was a small number of women with pre-existing heart disease and/or rheumatic conditions. Most deliveries (86.0%) were normal vaginal; the remaining were Cesarean section 2,146 (14.0%). The incidence of venous thromboembolism was 0.4 per 1,000 pregnancies, of which 83.3% were deep vein thrombosis and 16.7% were pulmonary embolism. In contrast to previous studies, 66.7% of venous thrombosis occurred in the first trimester. CONCLUSION: Chinese women had a substantially lower risk of venous thromboembolism during pregnancy and the postpartum period compared to that of Caucasians. The occurrence of pregnancy-related venous thromboembolism was largely confined to the early pregnancy period, probably related to the adoption of thromboprophylaxis, a lower rate of Cesarean section, and early mobilization.

Assessment of segmental left ventricular systolic function with real-time 3-dimensional echocardiography in patients with hypertensive hypertrophic cardiomyopathy / 中华医学超声杂志（电子版）

Objective To evaluate left ventricular function in patients with hypertensive hypertrophic cardiomyopathy(HHC)using real-time 3-dimensional echocardiography(RT-3DE).Methods Thirty patients with HHC and 32 control subjects were studied.Full-volume RT-3DE data from apical window were acquired,and regional volumetric time curves of 17 segments were obtained by fast 3-dimensional border detection software.Several left ventricular function parameters were calculated semiautomatically,including global left ventricular end-diastolic volume(EDV),end-systolic volume(ESV),left ventricular ejection fraction(LVEF),the ratio of ESV/EDV of 17 segments,the standard deviation(SD)and difference(Dif)(adjusted by the R-R interval) of time to minimum systolic volume(Tmsv)in 16 segments(Tmsv16-SD and Tmsv16-Dif).Results EDV and ESV were significantly larger in patients with HHC than that in control subjects[(88±29)ml vs (72±15) ml,t=-2.680,P=0.008;(28±10)ml vs (22±6 )ml,t=-2.613,P=0.01].HHC had a higher ratio of ESV/EDV at interventricular septum(IVS)compared with control group[mid-segments of anterior IVS:(40.51±20.28)% vs (26.43±10.10)%,t=-3.378,P=0.002;mid-segments of posterior IVS:(41.44±23.55)% vs (24.46±8.12)%,t=-3.688,P=0.001;apical segments of IVS:(30.96±21.31)% vs (19.53±7.33)%,t=-2.745,P=0.01].In patients with HHC,Tmsv16-SD and Tmsv16-Dif were significantly longer[(2.48±1.38)% vs (1.16±0.26)%,t=-5.117,P＜0.001;(7.67±5.07)% vs (3.95±1.48)%,t=-3.865,P＜0.001].And the prevalence of left ventricular dyssynchrony was higher than that in control subjects(43% vs 3%).Conclusions HHC patients may have regional left ventricular systolic dysfunction before global changes,and have a higher prevalence of left ventricular dyssynchrony.RT-3DE is a useful imaging modality for assessing left ventricular systolic function.