Biatrial pacing for patients with HFpEF undergoing cardiac surgery: the BiAPreserved study

Abstract Background Patients with HFpEF show mostly signs of diastolic dysfunction with is rooted in inner wall fibrosis. In addition, the diastolic dysfunction leads to higher atrial filling pressure and often to atrial asynchronies. This vicious circle leads to even more impaired ventricular filling. Moreover, those patients are prone to atrial fibrillation which also worsens the heart function since the active atrial contraction makes up significantly amount of ventricular filling. If those patients undergo cardiac surgery adequate ventricular filling and the absence of arrythmias (AF) are one of the main goals in perioperative therapy. We hypothesized that biatrial pacing (BiAP) in HFpEF patients undergoing cardiac surgery will eliminate the atrial asynchrony and reduce diastolic dysnfuction. Additionally, we aimed to reduce the AF risk and improve postoperative haemodynamics. Methods We implemented this prospective cohort study to evaluate the impact of BiAP on patients with HFpEF undergoing Coronary Artery Bypass Grafting (CABG) and/or Surgical Aortic Valve Replacement (SAVR). Patients were divided into two groups: those who received biatrial pacing and those who received the best standart of care. Patients received biatrial pacing for 5 consecutive days, with daily echocardiography, electrocardiogram and haemdynamic monitoring. The primary endpoints were diastolic dysfunction level using echocardiography, perioperative hemodynamics using advanced ICU monitoring and afib during time of pacing. Results In total 25 patients were enrolled with 12 patients receiving BiAP with a mean age of 70,6 years. Patients showed significantly improved haemodynamics while being biatrially stimulated during their perioperative time. Diastolic dysfunction levels and AF incidence were reduced during the time of biatrial pacing. Conclusion Biatrial pacing improves perioperative haemodynamics of HFpEF patients after cardiac surgery. Biatrial pacing also significantly improves the diastolic dysfunction due to resynchronization of atrial contractions. The AF incidence was significantly lower as well. In conclusion HFpEF patient profit greatly from improved haemodynamics and rhythm stability especially after cardiac surgery. This treatment could be an addition to the established perioperative and general treatment options for HFpEF patients.