title: An alternative subcoronary implantation technique decreases the risk of complete heart block after stentless aortic valve replacement.
abstract: BACKGROUND
  Stentless aortic valve prostheses have excellent hemodynamic profiles, but may be associated with an increased postoperative heart block when compared to conventional prostheses.
  
  
  OBJECTIVE
  To assess the effect of an alternative subcoronary implantation technique on postoperative complete heart block (CHB) and permanent pacemaker implantation (PPI) following aortic valve replacement (AVR) with stentless tissue valves.
  
  
  METHODS
  A total of 130 consecutive patients undergoing AVR with stentless tissue valves by a single surgeon were studied retrospectively.
  
  
  METHODS
  A stentless tissue valve was implanted into 80 patients using the conventional modified subcoronary implantation technique, and 50 patients received a stentless tissue valve by an alternative subcoronary technique in which the inflow suture line is raised at the level of right-non coronary commissure. Data were collected at the time of hospital discharge and at 6-12 months postoperatively.
  
  
  METHODS
  Independent samples t-test was used to compare continuous variables, and categorical variables were compared with the chi-square test.
  
  
  RESULTS
  Use of this new method reduced postoperative CHB (4.0% vs. 16.3%, P = 0.033), with fewer patients requiring PPI in the early postoperative period (6.0% vs. 18.8%, P = 0.041). Echocardiographic examination showed no differences in the effective orifice area, peak and mean aortic valve gradients, or left ventricular mass index between groups. Trivial or mild aortic regurgitation was found in 3.9% of patients with the conventional modified technique and 4.0% of patients undergoing the alternative technique, during follow-up (P > 0.05).
  
  
  CONCLUSIONS
  Compared to the conventional subcoronary implantation technique, the alternative subcoronary implantation technique reduces the incidence of new CHB and the requirement of PPI following AVR with stentless tissue valves while preserving mid-term hemodynamic function.
authors.affiliation: Department of Cardiothoracic Surgery, Changhai Hospital, The Second Military Medical University, Shanghai, China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Song
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Lehr
authors.forename: Shaohua
authors.initials: S
authors.lastname: Wang