Malhamé I, Mehta N, Raker CA, et al. - In the present study, the researchers sought to develop and validate a composite variable of cardiovascular severe maternal morbidity (CSMM) for use in epidemiologic studies. From 2007 to 2017, they analyzed delivery hospitalizations at an obstetric teaching hospital. Among 91,355 admissions for delivery, 113 potential CSMM cases were captured utilizing qualifying ICD codes. Of these, 65 have been true CSMM cases. The highest true-positive rates were given by indicators for acute myocardial infarction, cardiac arrest, and cardioversion. A novel CSMM composite variable had reasonable PPV but had limited sensitivity. This composite variable may allow for epidemiological studies designed to reduce maternal morbidity and mortality.