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Comparison of risk stratification models for pregnancy in congenital heart disease
Nathalie Denayer1, Els Troost2, Béatrice Santens2
1Faculty of Medicine, Department of Internal Medicine, KU Leuven, Belgium.
Insights
Pregnancy in women with congenital heart disease (CHD) poses cardiac risks. This study compared four risk models, finding all overestimated risk, with ZAHARA showing the closest prediction for maternal cardiac events.
Area of Science:
- Cardiology
- Maternal-Fetal Medicine
- Public Health
Background:
- Pregnancy in women with congenital heart disease (CHD) significantly increases the risk of maternal cardiac complications.
- Existing risk stratification models aim to predict adverse cardiac outcomes in pregnant women with CHD.
- This study provides an exploratory, head-to-head comparison of four commonly utilized risk models.
Purpose of the Study:
- To compare the predictive accuracy of four common risk stratification models for maternal cardiac complications in pregnant women with CHD.
- To evaluate the performance of CARPREG, CARPREG II, ZAHARA risk scores, and the mWHO risk classification in a real-world cohort.
Main Methods:
- A retrospective analysis of 100 pregnant women with CHD from the University Hospitals Leuven database.
- Calculation of individual and weighted average risk scores for each of the four models.
- Comparison of predicted risks against observed maternal adverse cardiac events (8% incidence).
Main Results:
- All four risk stratification models (CARPREG, CARPREG II, ZAHARA, mWHO) overestimated the maternal cardiac risk.
- Predicted risks were: CARPREG 10.1%, CARPREG II 8.6%, ZAHARA 11.1%, mWHO 12.4%.
- Observed event rates were 4.0% (CARPREG), 5.0% (CARPREG II), 8.0% (ZAHARA), and 8.0% (mWHO).
Conclusions:
- All evaluated risk models tend to overestimate maternal cardiac risk in pregnant women with CHD.
- The ZAHARA risk model demonstrated a closer approximation of actual maternal risk within this study cohort.
- Further research with larger populations is recommended to validate these findings and refine risk prediction.
Background:
Pregnancy in women with congenital heart disease (CHD) is associated with increased risk for maternal cardiac complications. Several risk stratification models are used to predict adverse cardiac outcome in women with CHD who become pregnant. This study was set up as an exploratory study to provide a head-to-head comparison of the 4 most commonly used models: CARPREG, CARPREG II and ZAHARA risk scores and mWHO risk classification.
Methods And Results:
We randomly selected 100 women from the database of paediatric and congenital heart disease of the University Hospitals Leuven. Individual pregnancy risk scores were retrospectively calculated and summarized in a weighted average risk for each risk stratification model. To evaluate accuracy of each model, the weighted average risk was plotted against the actual observed number of "cardiac events" as defined in the respective risk models. Maternal adverse cardiac events occurred in 8% of our study population. Weighted average risks were plotted versus the observed number of events for each model: 10.1% versus 4.0% for CARPREG, 8.6% versus 5.0% for CARPREG II, 11.1% versus 8.0% for ZAHARA and 12.4% versus 8.0% for the mWHO classification.
Conclusion:
All risk models overestimated maternal cardiac risk. The ZAHARA risk model appeared to be a closer reflection of maternal risk in our cohort of CHD patients. More research on a larger study population is needed.
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