Late conduction defects following aortic valve replacement

Background and aim of the study: The study aim was to determine the inciden ce and clinical significance of late cardiac conduction defects (CD) after aortic valve replacement (AVR). Methods: An analysis was made of 100 consecutive eases after AVR in a prosp ective outpatient evaluation program. Results: The perioperative (30-day) mortality rate was 5%, and incidence of perioperative pacemaker implantation 3%. Among patients, 19% had CDs befor e surgery; a normal ECG was present during all periods in 45% of patients. The most frequent perioperative CD was left anterior hemiblock (LAHB; n = 8 ), and the most frequent late CD was left bundle branch block (LBBB; n = 8) . Overall, 13.7% of operative survivors with normal preoperative and periop erative ECGs developed late CDs; one patient (1%) required pacemaker implan tation 82 months after AVR. A further three patients (3%) had worsening of pre-existent CDs. Late CDs occurred over a wide time range (3 to 102 months ) after surgery. Conclusion: There is an important incidence of CDs that occur late after AV R, even if the perioperative ECGs are normal; however, a need for late pace maker implantation is rare. As CDs may occur at any time after surgery, reg ular follow up with precise evaluation of ECGs is called for.