Stretch-induced syncope: An examination of a rarely recognized condition.

Stretch-Induced Syncope is an uncommon form of situational syncope triggered by stretching upper-back, neck, and shoulder muscles. A review of 133 publications in PubMed, Embase, Scopus, Web of Science, Scielo, and Google Scholar, using search terms such as "stretch syncope," "syncope with stretch," and "stretch-induced syncope," identified 12 studies describing 30 patient cases (ages 5-26). Stretch-induced syncope episodes were triggered by neck hyperextension and upper-back stretching, producing brief loss of consciousness. Early reports attributed these events to vertebral artery compression or carotid baroreceptor stimulation. However, recent data from simulated stretch testing demonstrate a pronounced vasodepressor response with diminished compensatory tachycardia compared to the heart rate increment during an active standing maneuver in the same patient; these findings are best accounted for by a neural reflex-mediated mechanism rather than mechanical vascular obstruction. Diagnosis is best achieved through careful history taking in the clinic and symptom reproduction with simultaneous video-EEG and beat-by-beat blood pressure monitoring during autonomic testing. No pharmacologic therapy has proven effective; patient education and avoidance of provoking maneuvers remain the mainstays of management. Greater awareness of stretch-induced syncope may prevent misdiagnosis, reduce unnecessary testing, and guide future investigation into the autonomic mechanisms of this reflex.