You will be shown inclusion or exclusion criteria for a clinical trial. Given these criteria, your task is to extract all unique entities of the following types: ["Observation", "Condition", "Procedure", "Drug", "Temporal", "Multiplier", "Qualifier", "Negation", "ReferencePoint", "Scope", "Value", "Mood", "Device", "Visit", "Measurement", "Person"].

Please return the output as a JSON object of the format: {"Condition" : ["breast cancer", ...], "Device" : ["ports", ...], "Drug" : ["Atenolol", ...], "Measurement" : ["blood pressure", ...], "Mood" : ["suspected", ...], "Multiplier" : ["more than two", ...], "Negation" : ["no", ...], "Observation" : ["history", ...], "Person" : ["male", ...], "Procedure" : ["surgery", ...], "Qualifier" : ["severe", ...], "ReferencePoint" : ["enrollment", ...], "Scope" : ["infection", ...], "Temporal" : ["one day", ...], "Value" : ["50%", ...], "Visit" : ["ICU", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Successful cardiac ablation for AF
Documented freedom from AF recurrence (symptomatic or asymptomatic arrhythmic recurrences lasting longer than 30 seconds) 3 months after successful cardiac ablation (AF recurrence during 3-month blanking period is excluded).
Patient must have been on a commercially approved anticoagulation therapy for at least two (2) months prior to randomization in the OAT Study.
CHADS2 score = 2 or CHA2DS2-VASc score (=3)
Left ventricular ejection fraction > 25%
LA size < 65
High risk for thromboembolic events (i.e., CHADS2 score = 2 or CHA2DS2-VASc score = 3) and require OAT before undergoing cardiac ablation
Able and willing to comply with all pre- and follow-up testing and requirements
Signed informed consent form
Age 18 years or older
{"Condition": ["AF", "arrhythmic recurrences", "AF recurrence"], "Device": [], "Drug": ["anticoagulation therapy", "OAT"], "Measurement": ["Left ventricular ejection fraction", "LA size", "CHA2DS2-VASc score", "CHADS2 score"], "Mood": [], "Multiplier": [], "Negation": ["freedom"], "Observation": ["risk for thromboembolic events"], "Person": ["Age"], "Procedure": ["cardiac ablation"], "Qualifier": ["Successful"], "ReferencePoint": ["randomization", "cardiac ablation"], "Scope": ["CHADS2 score = 2 or CHA2DS2-VASc score = 3"], "Temporal": ["at least two (2) months prior to randomization", "3 months after successful cardiac ablation", "before undergoing cardiac ablation"], "Value": ["=3", "18 years or older", "\u003c 65", "\u003e 25%", "longer than 30 seconds", "= 3", "= 2", "High"], "Visit": []}