Intramyocardial electrogram recordings (IMEG) for diagnosis of cellular and humoral mediated cardiac allograft rejection.
OBJECTIVE
The purpose of this study was to prove the reliability of intramyocardial electrogram (IMEG) recordings for diagnosis and treatment monitoring of (1) cellular and (2) humoral mediated allograft rejection after heart transplantation.


METHODS
Fifteen beagle dogs underwent heterotopic neck-heart transplantation. Eight of them were previously sensitized through several skin transplantations. IMEG recordings were performed daily. Donor-specific antibodies (IgG, IgM) were determinated in serum daily. Transmyocardial biopsies were performed every two days.


RESULTS
In the sensitized group (group I) accelerated rejection occurred under triple drug immunosuppression with cyclosporine A, azathioprine, and cortisone on the fifth postoperative day (range: 4th-5th). All episodes were detected through IMEG diagnosis. In each case rejection could be treated successfully. In the cellular mediated group (group II), the average sensitivity for rejection diagnosis of a single lead was 24% for the unipolar and 42% for the bipolar leads. When the voltages of different leads were summed up the sensitivity rose to 36% (3 unipolar), 81% (3 bipolar) and 100% (all leads). During rejection therapy the IMEG recovered within 24-48 hours.


CONCLUSIONS
The IMEG detects cellular and humoral mediated rejection early and with high reliability. The rejection-related changes of grade 2/3a rejection in IMEG seem to follow a Ofocal patternO similar to the histology. Therefore the recording of several, preferably bipolar, electrode configurations appears to enhance diagnostic reliability.
Knosalla
C
C
Department of Cardiothoracic and Vascular Surgery, German Heart Institute Berlin, Augustenburger Platz 1, Berlin, Germany.
Grauhan
O
O
Muller
J
J
Pfitzmann
R
R
Fietze
E
E
Cohnert
T
T
Volk
H D
HD
Hetzer
R
R
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D000917:Antibody Formation / Q000502:physiology; D001323:Autoantibodies / Q000032:analysis; D003348:Cortisone / Q000627:therapeutic use; D004285:Dogs; D004359:Drug Therapy, Combination; D004562:Electrocardiography / Q000379:methods*; D006084:Graft Rejection / Q000175:diagnosis* / Q000276:immunology / Q000517:prevention & control; D016027:Heart Transplantation; D007111:Immunity, Cellular / Q000502:physiology; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D011897:Random Allocation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014184:Transplantation, Homologous
D000893:Anti-Inflammatory Agents; D001323:Autoantibodies; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007166:Immunosuppressive Agents; D003348:Cortisone