Introduction: Persistent or new onset low flow (LF) as described by a stroke volume index (SVi) <35ml/min is reported to be indicative of poor outcomes after aortic valve replacement (AVR) in patients with severe aortic stenosis (AS) and preserved left ventricular ejection fraction (LVEF). We report post-operative haemodynamics in a cohort of propensity-matched patients undergoing AVR by Perceval sutureless valve (PSV) compared with conventional stented valves (CSV).
Hypothesis: The use of PSV in patients with severe AS and preserved LVEF does not affect SVi when compared with CSV.
Methods: The cardiac surgery database was interrogated for all patients undergoing AVR between 2014 and 2017. Out of 432 patients with severe AS and normal LVEF, a cohort of 29 patients consecutive patients who underwent AVR with PSV were propensity-matched with 29 patients who had CSV. Preoperative patient characteristics, operative details, echocardiographic data and early clinical outcomes were collated and rates of persistent or new onset LF analysed with standard statistical techniques.
Results: The groups were well matched with paradoxical low LF AS present in 35.0% of PSV and 42.3% of CSV patients pre-operatively, with a median pre-operatively SVi of 37.8±10.5 ml/min and 34.2±9.5ml/min in the PSV and CSV group: respectively (p=0.42). There were no perioperative deaths or episodes of low cardiac output state. Pre-discharge LVEF was similar in the PSV and the CSV groups. Postoperative persistent or new-onset LF was more prevalent in the PSV group compared with the CSV group with a prevalence of 47.4% and 34.7% respectively.
Conclusion: In patients with severe AS and normal LVEF, AVR with PSV is associated with a higher incidence of persistent or new onset LF compared with CSV. Close follow up is essential to determine if this translates into increased adverse medium and long-term outcomes.