Baseline cardiac biomarker analysis from the basel postpartum hypertension registry

Objective: Postpartum hypertension (PPHT) is defined by elevated blood pressure measurements after birth of more than 140 mmHg systolic and more than 90 mmHg diastolic, that persist or develop directly after pregnancy and is associated with adverse cardiovascular and renal outcome. Aim of the current analysis was the evaluation of different prognostic cardiac and stress related biomarkers like cardiac troponin T (cTnT), N-terminal pro-Brain Natriuretic Peptide (NT-proBNP) and growth differentiation factor 15 (GDF-15) in the setting of PPHT. Design and method: Enrollment for the prospective observational Basel Postpartum Hypertension Registry began in June 2020 at the University Hospital Basel. Women with preexisting hypertension, hypertensive disorders of pregnancy (HDP), and de novo postpartum hypertension were enrolled and followed up in structured management program. Clinical history and lab values were collected out of the electronic health records. Additional blood samples were stored for further evaluation. The present analysis contains biomarker analysis of a subset of 58 out of 288 patients using blood samples taken within one week of giving birth. Serum samples were analyzed for detectable levels of cTnT, NT-proBNP and GDF-15 at the department for Laboratory Medicine at University Hospital Basel using electrochemiluminescence immunoassay Elecsys on the Cobas e 801 platform (Roche Diagnostics, Rotkreuz, Switzerland). Results: Mean age of the patients from whom we measured biomarkers at baseline was 34±4.7. Mean troponin was 8.5 ng/l ±2.2 with normal cuttoffs for this age group being 14ng/l and sex specific cutoffs at 9ng/l. NT-proBNP was 229.86ng/l ±80.4, with 125ng/l being the normal cut off in an acute disease setting. Mean GDF-15 was 1895.8ng/l ±323.5 with correlating normal values in healthy populations in the same age range being 564 ± 223 ng/l. Conclusions: This first biomarker analysis shows a trend of elevated NT-proBNP and GDF-15 which are associated with cardiovascular disease or stress. Cardiac troponin T was not elevated in most of the patients, but in a subset of 13 patients. Further analysis and long term outcome correlations remains to be established and may be part of the follow-up analyses of the Basel PPHT cohort.