The effect of slow breathing exercise on heart rate and blood pressure in patients undergoing percutaneous coronary intervention: a randomized controlled trial

Aim To determine the effects of slow breathing exercise (SBE) on heart rate (HR) and blood pressure (BP) in patients after percutaneous coronary intervention (PCI). Methods and results The study is a single-blind, randomized controlled trial. Seventy-eight eligible patients after primary PCI were divided randomly into either the control group or the trial group. The control group only received routine post-PCI care. In addition to routine care, participants in the trial group performed SBE at home, two to three times for a total of 30 min every day for 12 weeks. The main outcomes were HR and BP measured in the office and at home. The secondary outcome was compliance with the breathing exercise. Patients allocated to the trial group, on average, performed 5.21 days/week for 26.00 min/day. The trial group showed a significant reduction in HR of 3.95 b.p.m. (P = 0.004) measured in the office. The reduction in HR measured in the office was greater for the trial group, with a significant difference between the two groups (P = 0.005). There was no significant difference between the two groups in HR measured at home. There was also no significant difference in BP measured in the office or at home between the two groups. Conclusion Slow breathing exercise is an effective non-pharmacological method to reduce HR in patients undergoing PCI. Further study is needed to confirm whether the intervention is effective on BP. Registration The trial was registered at the Chinese Clinical Trial Registry: ChiCTR-IOR-17012525