Background and aim of the study: The study aim was to determine the incidence and clinical significance of late cardiac conduction defects (CD) after aortic valve replacement (AVR).
Methods: An analysis was made of 100 consecutive cases after AVR in a prospective outpatient evaluation program.
Results: The perioperative (30-day) mortality rate was 5%, and incidence of perioperative pacemaker implantation 3%. Among patients, 19% had CDs before 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 perioperative ECGs developed late CDs; one patient (1%) required pacemaker implantation 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 AVR, even if the perioperative ECGs are normal; however, a need for late pacemaker implantation is rare. As CDs may occur at any time after surgery, regular follow up with precise evaluation of ECGs is called for.