Safety and efficacy of the 0 h/3 h protocol for rapid rule out of myocardial infarction.
BACKGROUND
The early and accurate diagnosis of acute myocardial infarction (AMI) is an important medical and economic challenge. We aimed to prospectively evaluate the performance of the new European Society of Cardiology rapid 0-hour/3-hour (0 h/3 h) rule out protocol for AMI.


METHODS
We enrolled 2,727 consecutive patients presenting with suspected AMI without persistent ST-segment elevation to the emergency department in a prospective international multicenter study. The final diagnosis was adjudicated by 2 independent cardiologists. The performance of the 0 h/3 h rule out protocol was evaluated using 4 high-sensitivity (primary analysis) and 3 sensitive cardiac troponin (cTn) assays.


RESULTS
Acute myocardial infarction was the final diagnosis in 473 patients (17.3%). Using the 4 high-sensitivity cTn assays, the 0-hour rule out protocol correctly ruled out 99.8% (95% [confidence interval] CI, 98.7%-100%), 99.6% (95% CI, 98.5%-99.9%), 100% (95% CI, 97.9%-100%), and 100% (95% CI, 98.0%-100%) of late presenters (>6 h from chest pain onset). The 3-hour rule out protocol correctly ruled out 99.9% (95% CI, 99.1%-100%), 99.5% (95% CI, 98.3%-99.9%), 100% (95% CI, 98.1%-100%), and 100% (95% CI, 98.2%-100%) of early presenters (<6 h from chest pain onset). Using the 3 sensitive cTn assays, the 0-hour rule out protocol correctly ruled out 99.6% (95% CI, 98.6%-99.9%), 99.0% (95% CI, 96.9%-99.7%), and 99.1% (95% CI, 97.2%-99.8%) of late presenters; and the 3-hour rule out protocol correctly ruled out 99.4% (95% CI, 98.3%-99.8%), 99.2% (95% CI, 97.3%-99.8%), and 99.0% (95% CI, 97.2%-99.7%) of early presenters. Overall, the 0 h/3 h rule out protocol assigned 40% to 60% of patients to rule out. None of the patients assigned rule out died during 3-months follow-up.


CONCLUSIONS
The 0 h/3 h rule out protocol seems to allow the accurate rule out of AMI using both high-sensitivity and sensitive cTn measurements in conjunction with clinical assessment. Additional studies are warranted for external validation.
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland; Department of Internal Medicine, University Hospital, Basel, Switzerland; Department of Intensive Care, University Hospital Basel, Basel, Switzerland.
Karin
K
Wildi
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland; Department of Internal Medicine, University Hospital, Basel, Switzerland.
Berit
B
Nelles
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Raphael
R
Twerenbold
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland; Department of Internal Medicine, University Hospital, Basel, Switzerland; Servicio de Urgencias y Pneumologia, CIBERES ISC III, Hospital del Mar-Institut Municipal d'Investigació Mèdica, Barcelona, Spain.
Maria
M
Rubini Giménez
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Tobias
T
Reichlin
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Hélène
H
Singeisen
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Sophie
S
Druey
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Philip
P
Haaf
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Zaid
Z
Sabti
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Petra
P
Hillinger
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Cedric
C
Jaeger
Servicio de Urgencias y Pneumologia, CIBERES ISC III, Hospital del Mar-Institut Municipal d'Investigació Mèdica, Barcelona, Spain.
Isabel
I
Campodarve
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Philip
P
Kreutzinger
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Christian
C
Puelacher
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Zoraida
Z
Moreno Weidmann
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Mathias
M
Gugala
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Gilles
G
Pretre
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Stephanie
S
Doerflinger
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Max
M
Wagener
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Fabio
F
Stallone
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Michael
M
Freese
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Claudia
C
Stelzig
Laboratory Medicine, University Hospital Basel, Basel, Switzerland.
Katharina
K
Rentsch
Department of Medicine, Kantonsspital Olten, Olten, Switzerland.
Stefano
S
Bassetti
Emergency Department, University Hospital, Basel, Switzerland.
Roland
R
Bingisser
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland.
Stefan
S
Osswald
Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Basel, Switzerland. Electronic address: christian.mueller@usb.ch.
Christian
C
Mueller
D000368:Aged; D000369:Aged, 80 and over; D002637:Chest Pain / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D002985:Clinical Protocols; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D011446:Prospective Studies; D013997:Time Factors; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
D019210:Troponin I; D020107:Troponin T