The role of mean arterial pressure/heart rate ratio as a hemodynamic predictor of an adverse outcome in women with hypertensive disorders of pregnancy: a secondary analysis of the PYTT study

Hypertensive disorders of pregnancy (HDP) have been suggested to derive and be sustained from an altered cardiovascular adaptation of the mother to the pregnancy that influences the clinical severity of the disease.1 Specifically, two phenotypes of HDP have been described based on the maternal hemodynamic profiles: one characterized by a reduced cardiac output (CO) and increased systemic vascular resistances (SVR), also named as “hypodynamic pattern” and the other characterized by a normal or increased CO and reduced SVR, also named as “non-hypodynamic pattern.”2 On this ground, in hypertensive pregnant women, the hemodynamic assessment has emerged as a potential strategy for tailoring the antihypertensive therapy (vasodilators in women with hypodynamic pattern and negative inotropes in those with nonhypodynamic pattern) and ultimately improving maternal and perinatal outcomes.3 The need of echo or noninvasive devices and of trained clinicians represent the major limitations to the routine implementation of this strategy. In a recent consensus, the ratio between mean arterial pressure (MAP) and heart rate (HR) has been proposed as a surrogate of the noninvasive hemodynamic evaluation to distinguish those hypertensive women with “hypodynamic pattern” (MAP/HR≥1.4), from those with “non-hypodynamic pattern” (MAP/HR<1.4).4 However, there is little data on the clinical usefulness of this parameter in the context of preeclampsia. The aim of our study was to investigate whether in women with established preeclampsia the MAP/HR ratio may be helpful in predicting the occurrence of adverse maternal and perinatal outcome