Inappropriate bradycardia in Ebola virus disease.
BACKGROUND
As part of French assistance for the outbreak of Ebola virus disease in west Africa, a military treatment center for infected healthcare workers was deployed in Conakry, Guinea. Although some cases of bradycardia have been reported since the first Ebola outbreak, they have never been documented to our knowledge. We studied heart rhythm in patients with Ebola virus disease to analyze inappropriate bradycardia and discuss its mechanism.


METHODS
Nine patients who tested positive for Ebola were admitted in March 2015. Baseline clinical data were noted at admission and twice a day during follow-up, and laboratory analyses (with troponin testing) were performed.


RESULTS
At admission, patients had no or moderate tachycardia (pulse = 82 ± 27 bpm). Among them, a 32-year-old midwife admitted on her fourth day of symptoms had marked bradycardia: 43 bpm. ECG showed sinus bradycardia with no conduction disturbances or repolarization anomalies; findings were similar for the three other patients with bradycardia (< 60 bpm). During follow-up, her pulse gradually increased, as it did for the other three; all four recovered.


CONCLUSIONS
Despite several factors likely to promote tachycardia, we observed no or only moderate tachycardia in all patients with Ebola. In our study, ECG recorded sinus rhythm, without significant node dysfunction or atrioventricular block. In the absence of any evidence of myocarditis, we discuss the possibility of a central nervous system cause, associated with encephalitis.


CONCLUSIONS
We observed relative or marked bradycardia in our patients infected with Ebola. We hypothesize that its causal mechanism was encephalitis.
Service de cardiologie, hôpital Sainte-Anne, boulevard Sainte Anne, BP 600, 83800 Toulon cedex 9, France.
G
G
Cellarier
Service de réanimation, hôpital Sainte-Anne, Toulon, France.
J
J
Bordes
Service de neurologie, hôpital Percy, Clamart, France.
T
T
De Greslan
Médecine interne et infectiologie, hôpital Legouest, Metz, France.
L
L
Karkowski
Anesthésie réanimation, hôpital Legouest, Metz, France.
N
N
Gagnon
Médecine interne, hôpital du Val De Grace, Paris, France.
M
M
Billhot
Médecine interne, hôpital Percy, Clamart, France.
J-M
JM
Cournac
Médecine interne, hôpital Clermont Tonnerre, Brest, France.
C
C
Rousseau
Service de biologie, hôpital Percy, Clamart, France.
C
C
Mac Nab
Service de biologie, hôpital Robert Pique, Bordeaux, France.
P
P
Dubrous
D000328:Adult; D001919:Bradycardia / Q000209:etiology*; D004660:Encephalitis / Q000150:complications; D005260:Female; D019142:Hemorrhagic Fever, Ebola / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged
Ebola virus; Guinea; bradycardia; electrocardiogram; mechanisms