A novel strategy for evaluating tilt test in athletes with syncope

Area of Science:

• Cardiology
• Sports Medicine
• Diagnostic Medicine

Background:

• The tilt test is a diagnostic tool for reflex syncope (RS).
• Standard tilt testing exhibits low sensitivity in identifying RS, particularly in athletic populations.
• Pharmacological provocation is often used but can be problematic.

Purpose of the Study:

• To implement a novel, non-pharmacological diagnostic strategy for the tilt test in athletes.
• To enhance the sensitivity of the tilt test for diagnosing reflex syncope using hemodynamic criteria.

Main Methods:

• A passive tilt test was conducted for 30 minutes on 132 athletes (53 with RS history, 79 without).
• Hemodynamic parameters, heart rate variability (HRV), and baroreflex sensitivity were measured.
• A new stratification method was applied to tilt test results based on total peripheral resistance index (TPRI) and cardiac index (CI).

Main Results:

• Standard tilt testing showed 34% sensitivity and 94% specificity for RS.
• Athletes with RS exhibited distinct hemodynamic profiles during tilt testing, including increased heart rate (HR), stroke index (SI), and cardiac index (CI), alongside decreased TPRI.
• The novel stratification, defining positive results with TPRI <2800 dyne·s m(2)/cm(5) and CI >3 l/(min·m(2)), achieved 85% sensitivity and 76% specificity in diagnosing RS among athletes with initially negative tilt tests.

Conclusions:

• A novel stratification strategy based on hemodynamic criteria significantly improves tilt test sensitivity for diagnosing reflex syncope in athletes.
• This non-pharmacological approach offers a more effective diagnostic method for RS in this population.