Eosinophilic myocarditis in patients awaiting heart transplantation.
OBJECTIVE
To determine the possible causative agents of eosinophilic or hypersensitivity myocarditis in patients awaiting heart transplantation.


METHODS
Consecutive patient series.


METHODS
Large university-affiliated hospital.


METHODS
A total of 190 consecutive patients who had heart transplantation at our center.


METHODS
The myocardium of the explanted heart was examined for a mixed inflammatory cell infiltrate containing an identifiable component of eosinophils. The relative quantity of each cell type was evaluated by a semiquantitative grading system (scored 0 to 3). The clinical findings and medications were reviewed, and patients were followed after heart transplantation.


RESULTS
Eosinophilic myocarditis (EM) was found in the explanted heart in 14 patients (7.4%). Myocardial infiltration by eosinophils ranged from mild (n = 6), often focal involvement to marked (n = 8), usually multifocal or widespread involvement. Twelve patients (86%) had peripheral blood eosinophilia before transplant, and in ten (71%), the eosinophil count at least doubled. Loop or thiazide diuretics were used in all 14 patients, and angiotensin-converting enzyme inhibitors were used in 12. Preoperative characteristics were similar in patients with and without EM, except for a higher frequency of inotropic support and assist devices in EM patients. Dobutamine was used in 12 (86%) and dopamine in seven (50%; one with dopamine alone), and one patient (7%) received neither dopamine nor dobutamine. In two patients receiving dobutamine and one receiving dopamine, tapering or discontinuation of the inotropic infusion resulted in a significant diminution of the peripheral eosinophilia and the EM before transplantation. Postoperative survival in patients with and without EM was similar at 8 yrs (50% +/- 13% and 54% +/- 4%, p =.34). No patient in this study has had EM on biopsy after transplant.


CONCLUSIONS
EM is a complication of multiple drug therapy in patients awaiting heart transplantation, and should be suspected when peripheral blood eosinophilia is present or the eosinophil count increases by at least two-fold. EM may be related to intravenous inotropic therapy, and this is the first study to document improvement in myocardial pathology after inotropic drug withdrawal. Hypersensitivity to thiazide and loop diuretics, angiotensin-converting enzyme inhibitors, and antibiotics must also be considered. Survival after heart transplantation is not impaired, and postoperative steroid therapy may prevent EM.
Takkenberg
Johanna J M
JJ
Division of Cardiothoracic Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
Czer
Lawrence S C
LS
Fishbein
Michael C
MC
Luthringer
Daniel J
DJ
Quartel
Adrian W
AW
Mirocha
James
J
Queral
Carmen A
CA
Blanche
Carlos
C
Trento
Alfredo
A
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000009:adverse effects; D002316:Cardiotonic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D004232:Diuretics / Q000008:administration & dosage / Q000009:adverse effects; D004280:Dobutamine / Q000008:administration & dosage / Q000009:adverse effects*; D004298:Dopamine / Q000008:administration & dosage / Q000009:adverse effects; D004342:Drug Hypersensitivity / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D004359:Drug Therapy, Combination; D004802:Eosinophilia / Q000139:chemically induced* / Q000453:epidemiology / Q000276:immunology / Q000473:pathology; D005260:Female; D016027:Heart Transplantation / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009205:Myocarditis / Q000139:chemically induced* / Q000453:epidemiology / Q000276:immunology / Q000473:pathology; D018709:Statistics, Nonparametric; D015996:Survival Rate; D014481:United States / Q000453:epidemiology
D000806:Angiotensin-Converting Enzyme Inhibitors; D002316:Cardiotonic Agents; D004232:Diuretics; D004280:Dobutamine; D004298:Dopamine