Postoperative Dipping Patterns of Mean Arterial Pressure and Mortality After Coronary Artery Bypass Grafting

Blood pressure dipping patterns have long been considered to be associated with adverse events. We aimed to investigate whether dipping patterns of postoperative MAP were related to 90-day and hospital mortality in patients undergoing CABG. Four thousand three hundred ninety-one patients were classified into extreme dippers (night-to-day ratio of MAP ≤ 0.8), dippers (0.8 < night-to-day ratio of MAP ≤ 0.9), non-dippers (0.9 < night-to-day ratio of MAP ≤ 1), and reverse dippers (> 1). Compared with non-dippers, reverse dippers were at a higher risk of 90-day mortality (aHR = 1.58; 95% CI, 1.10–2.27) and hospital mortality (aOR = 1.97; 95% CI, 1.12–3.47). A significant interaction was observed between hypertension and dipping patterns (P for interaction = 0.02), with a significant increased risk of 90-day mortality in non-hypertensive reverse dippers (aHR = 1.90; 95% CI, 1.17–3.07) but not in hypertensive reverse dippers (aHR = 1.26; 95% CI, 0.73–2.19).

Patients with the reverse dipping pattern have a higher risk of 90-day mortality after receiving CABG, while the association between dipping patterns and mortality was moderated by hypertension.