Pregnancy has a profound impact on the cardiovascular system. Pregnancy-related cardiovascular adaptations contribute to life-threatening complications not only in individuals with pre-existing heart disease, but also in those with no prior cardiac history who are susceptible or unable to adapt to these changes, due to health conditions such as anaemia. Not surprisingly, cardiovascular conditions constitute the leading cause of non-obstetric mortality and severe morbidity in pregnancy worldwide. At least 50% of cardiovascular morbidity and mortality is preventable and individuals from minoritized backgrounds are disproportionately affected. Risk factors associated with these disparities in preventable cardiovascular mortality and morbidity remain unexplored.
Our overarching goal is to use an interdisciplinary and multi-provincial approach, grounded in principles of Equity, Diversity, and Inclusion, to establish pan-Canadian networks of excellence aimed at reducing pregnancy-related cardiovascular mortality and morbidity and the inherent disparities in outcomes. Our goal will be achieved through three specific objectives:
- Reviewing all pregnancy-related cardiovascular morbidity and mortality events in Canada through the establishment of a Canadian Obstetric Survey System (CanOSS)
- Assessing factors influencing post- and inter-pregnancy cardiovascular recovery in persons with known cardiac disease through establishment of a Canadian Cardio-Obstetrics Collaboration (CCOC)
- Exploring reasons for high adverse outcomes in pregnant individuals with rheumatic valvular heart disease, which disproportionately affects minoritized, immigrant, and Indigenous populations and facilitating research studies through the Canadian Network for Valvular Heart Disease (CanVaHD).
Program Area 1 [CanOSS]: We will adapt the confidential enquiries approach that have resulted in a substantial reduction in severe adverse pregnancy events in several high-income countries to the Canadian context through a process of integration and incorporation of mainstream, cultural, and spiritual knowledge that is unique to Canada. Building on two Canadian Institutes for Health Research (CIHR)-funded projects – a feasibility study on the development of a Hub for knowledge mobilization (KM) activities led by the PA and NPA, we propose conducting the first CanOSS study involving all 289 facilities providing pregnancy care to review clinical and non-clinical factors responsible for severe cardiovascular events in Canada, understand reasons behind disparities, formulate and implement targeted recommendations to address identified issues, and assess the societal and economic impact of the initiative. This will be followed by a cross validation study to determine the most efficient event identification strategy for ongoing surveillance.
Program Area 2 [CCOC]: Through the development of a cardio-obstetrics network initially involving nine cardio-obstetrics units across Canada, expanding over the duration of the study, we will conduct a prospective multicentre cohort study to compare cardiac remodelling in individuals with and without heart disease late after pregnancy, to compare cardiovascular risk profiles (e.g., cholesterol, glucose, blood pressure) after pregnancy in individuals with and without heart disease, and to examine the relationship between adverse cardiovascular events in individuals with heart disease after childbirth and their association with a) cardiac remodelling and b) the development of cardiovascular risk factors.
Program Area 3 [CanVaHD]: Leveraging collaborations through Program Areas 1 and 2, we will develop a network of all facilities that care for pregnant individuals with rheumatic heart disease. We will first perform a pan-Canadian external validation study for a risk-stratification system developed and validated specifically for this population as well as a nationwide case series on maternal and fetal-neonatal outcomes following diverse approaches to anticoagulation management in pregnant individuals with mechanical heart valves, which requires making trade-offs between maternal and fetal/neonatal health.
Expertise and Feasibility: The NPA, PAs, and CC Theme Leads represent diverse experiential, clinical, research, and backgrounds and are considered world leaders in cardio-obstetrics and patient-centered care. They have a history of completing large collaborative projects through competitive grant funding.
Expected Outcomes: The proposed networks are not only expected to demonstrate a reduction in severe pregnancy-related cardiovascular events by the end of the study period, but will also serve as platforms for conducting prospective research, consolidating Canada’s position as world leaders in research and quality assurance on pregnancy-related cardiovascular mortality and morbidity.