Table 2.
Final assessment questions, with LHRsa for cardiogenic syncope.
| Question | Reference | LHR+ | LHR– | |
| Is the patient less than or equal to 35 years of age? | [16] | 0.13 | 3.24 | |
| Does the patient have a history of heart disease (atrial fibrillation/flutter, ventricular tachycardia, heart block, heart failure, stable ischemic heart disease, valvular heart disease)?b | [15,16,23] | 2.93 | 0.74 | |
| Did the syncopal episode occur in the context of any of the following: warm or crowded place, prolonged standing, fear, emotion, pain, or using the toilet?b | [16] | 0.167 | 1.43 | |
| Was the syncopal episode associated with chest pain? | [23,24] | 4.25 | 0.881 | |
| Was the syncopal episode associated with palpitations? | [13,15,16,23-25] | 3.78 | 0.853 | |
| Was the syncopal episode associated with exertion? | [13,15] | 4.36 | 0.896 | |
| Was the syncopal episode associated with position change?c | — | NAd | NA | |
| Was the syncopal episode associated with hypoxia? | [16] | 3.74 | 0.94 | |
| Was the syncopal episode associated with nausea, vomiting, or a warm/flushed feeling? | [13,15,16,23-25] | 0.354 | 1.38 | |
| Does the patient describe any of the following: severe headache, focal neurologic deficit, or postictal state?e | [16] | 0.170 | 1.21 | |
| Were there convulsions witnessed associated with the syncope?c | — | NULLf | NULLf | |
| Is there a new murmur on exam?c | — | NULLf | NULLf | |
| Is the resting SBPg <90 mmHg or >180 mmHg? | [16] | 5.88 | 0.894 | |
| Were orthostatic vitals positive (>20 mmHg drop in SBP or >30 beats per minute increase in heart rate)?h | — | NULLf | NULLf | |
| Do you think orthostasis is the cause for syncope?h | — | NULLf | NULLf | |
| Were there any new focal neurologic deficits on physical exam?e | — | NULLf | NULLf | |
| Is the QRS axis abnormal (<–30 degrees or >100 degrees)?b | — | NULLf | NULLf | |
| Is the QRS duration prolonged (>120 ms)?b | — | NULLf | NULLf | |
| Is the corrected QT interval prolonged (>480 ms)?b | — | NULLf | NULLf | |
| Is the troponin elevated (high-sensitivity cardiac troponin t>14 ng/L)?b | [26] | 1.98 | 0.534 | |
aLHR: likelihood ratio.
bInput for the Canadian Syncope Score (CSS).
cIncluded to prompt additional considerations.
dNA: not available.
eArtificially weighted for neurogenic loss of consciousness (LOC).
fRatios not found in the literature.
gSBP: systolic blood pressure.
hArtificially weighted for orthostatic syncope.