Carotid Sinus Massage in Syncope Evaluation: A Nonspecific and Dubious Diagnostic Method

Area of Science:

• Cardiology
• Neurology
• Clinical Medicine

Background:

• Carotid sinus hypersensitivity (CSH) is frequently identified during syncope evaluations, but its clinical significance remains debated.
• A proposed criterion by Solari et al. uses a systolic blood pressure (SBP) cut-off of ≤ 85 mmHg to better define vasodepressor (VD) responses.

Discussion:

• Carotid sinus massage (CSM) responses, including cardioinhibitory (CI) and VD, did not significantly differ between patients with and without syncope.
• A substantial proportion of both symptomatic and asymptomatic individuals met the proposed SBP ≤ 85 mmHg criterion.
• Symptoms during CSM were associated with SBP decrease below 90 mmHg and/or asystole > 2.5 seconds, irrespective of syncope history.

Key Insights:

• CSM hemodynamic responses are similar in patients with and without syncope, indicating CSH may be an unspecific finding.
• The proposed SBP ≤ 85 mmHg criterion did not effectively differentiate syncope causes.
• Clinical correlation is crucial, as CSM findings alone are insufficient for diagnosing syncope.

Outlook:

• Further research should focus on refining diagnostic criteria for CSH.
• Integrating CSM results with long-term ECG monitoring may improve syncope diagnosis accuracy.
• Investigating alternative or complementary diagnostic methods for CSH is warranted.