Background and objective: Endomyocardial biopsy is the gold standard for monitoring rejection in cardiac recipients. The death rate due to rejection with this invasive method is 5-6 % in the first postoperative year. The aim of this retrospective data analysis from cardiac recipients was to prove the diagnostic reliability of a non-invasive electrophysiological method for rejection monitoring.
Patients and methods: We daily analyzed the QRS-complex amplitude of the intramyocardial electrogram, which we received over a period from one year via a pacemaker with a telemetric capability. The diagnostic guideline for a suspected rejection was the reduction of the QRS-complex amplitude by more than 8 %. Out of 734 patients 558 were included in the study. Biopsy was only performed when the non-invasive rejection monitoring data (QRS-complex amplitude plus echocardiography) showed a discrepancy for rejection.
Results: None of the patients died due to rejection, 273 at least once underwent a biopsy, and 285 never had a biopsy. The method reached a sensitivity of 0.9777, a specificity of 0.9634, a negative predictive value of 0.9850, and a positive predictive value of 0.9459.
Conclusion: Daily electrophysiological non-invasive monitoring of rejection seems to be superior to endomyocardial biopsy. Death of patients due to rejection can be minimised. The number of necessary biopsies can be drastically reduced when compared to the usual number performed.