[External and internal electrical cardioversion: comparative, prospective evaluation of cell damage by means of troponin I].
OBJECTIVE
In this study we measured the concentrations of cardiac troponin I (cTnI) and several biochemical markers of myocardial damage after elective external cardioversion or internal cardioversion by specific catheters or automatic defibrillators.


METHODS
Biochemical markers were analyzed prospectively for 30 consecutive patients after electrical cardioversion. Concentrations of cTnI, myoglobin, creatine kinase (CK), CK-MB and the MB/CK ratio were determined in samples before cardioversion and 2, 8 and 24 h later. The shock energy ranged from 50 to 360 joules (235 106 joules) in external cardioversions and from 3 to 37 joules (15 8 joules) in internal cardioversions.


RESULTS
We detected abnormal concentrations of CK, myoglobin, CK-MB and MB/CK in 33% of the patients after external cardioversion. The concentrations of cTnI remained within normal limits at all times, with no elevations detected. Whereas no abnormal concentration of any biochemical marker was detected in any patient who required internal cardioversion for atrial fibrillation, two patients who underwent external cardioversion from an automatic defibrillator did have abnormal concentrations of CK-MB, myoglobin, and even of cTnI.


CONCLUSIONS
The concentration of cTnI remained below the detection limit after external cardioversion, even though the other more non-specific markers changed. No enzyme alteration was detected in patients who underwent internal cardioversion of atrial fibrillation.
del Rey Sánchez
José M
JM
Servicios de Bioquímica Clínica, Hospital Ramón y Cajal, Universidad de Alcalá, Madrid, Spain.
Hernández Madrid
Antonio
A
González Rebollo
José M
JM
Peña Pérez
Gonzalo
G
Rodríguez
Aníbal
A
Savova
Detelina
D
Cano Calabria
Lucas
L
Cabeza
Pedro
P
Cascón Pérez
José D
JD
Gómez Bueno
Manuel
M
Mercader
José
J
Ripoll
Eduardo
E
Moro
Concepción
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000628:therapy*; D015415:Biomarkers / Q000097:blood; D009202:Cardiomyopathies / Q000097:blood / Q000209:etiology* / Q000473:pathology*; D004554:Electric Countershock / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I