Table 2 Clinical trial endpoints that may be used to demonstrate cardiac device efficacy in neuroprotection
Endpoint measure | Advantages | Disadvantages |
|---|---|---|
Incidence of clinical outcomes (such as stroke, transient ischemic attack) | Clear indicator of neurologic events | Low incidence rate demands large sample size to observe effect |
Can be reported in a standardized fashion using the NIH stroke scale and Modified Rankin scale. | Cost limitations may prohibit large sample size | |
May miss silent/subtle clinical events | ||
Neuroimaging (such as diffusion-weighted magnetic resonance imaging, transcranial Doppler ultrasound) | Easy and reproducible | No standardized definition of endpoint |
Widely available | Variation in reporting makes cross-study comparisons difficult | |
May be contraindicated in some patients (for example, those with pacemakers) | ||
Radiographic interpretation may be subjective | ||
Biomarkers (such as S100β, apolipoprotein A1, neuron-specific enolase) | Easy | Validity not established |
Reproducible | Normal range for certain patient populations unknown | |
Objective | Timing is critical | |
Less biased | Expensive | |
| Â | Â | Subject to laboratory errors |