Registry of Pregnancy and Cardiac Disease 2.0 to Bedside: A systematic review and meta-analysis to derive a B-type natriuretic peptide–oxygen saturation–pulmonary hypertension composite score for pregnancy risk in congenital heart disease

Pregnancy in women with congenital heart disease (CHD) presents unique and evolving risks that are poorly captured by existing lesion-based counseling tools. Recent registry insights from the Registry of Pregnancy and Cardiac Disease (ROPAC) and emerging data on B-type natriuretic peptide (BNP/NT-proBNP), resting oxygen saturation (SpO 2 ), and pulmonary hypertension (PH) (BNP–O 2 –PH) suggest an opportunity for a physiology-driven risk score. We performed a comprehensive systematic review of studies published between January 2010 and August 2024, retrieving 1238 database records, screening 630 after de-duplication, reviewing 162 full texts, and including 35 reports that met pre-specified criteria. Two reviewers extracted data on biomarker thresholds, SpO 2 , and PH severity; study designs, populations, exposures, and outcomes; and assessed risk of bias using the ROBIS/AMSTAR-2 instruments. We synthesized findings across eight candidate domains and developed a tabulated composite “ROPAC 2.0” score. Key thresholds included NT-proBNP ≥300 pg/mL, SpO 2 <92%, and confirmed PH (≥50 mmHg) as strong independent predictors of maternal major adverse cardiac events, Intensive Care Unit-level care, and adverse fetal outcomes. The proposed composite integrates anatomy, biomarker, physiologic, and functional variables into a bedside tool that outperforms traditional lesion-only stratification. The framework offers three risk tiers (green/amber/red) linked to surveillance intensity and delivery planning. Validation within prospective multicentre ROPAC cohorts is now essential. Institutional electrocardiogram-lab/maternal cardiac programs and national policy frameworks should adopt this paradigm shift to ensure women with CHD-pregnancy receive precision-guided surveillance and intervention, fulfilling modern perinatal-cardiac care imperatives.