Introduction: Exercise induced inspiratory stridor (EIIS) is common in top athletes and often misdiagnosed as asthma. EIIS has been attributed to inappropriate adduction of the vocal cords (VCD), and some researchers argue that exercise induced VCD may be diagnosed from a medical history alone or with laryngoscopy performed during maximum voluntary ventilation (MVV) or similar breathing exercises at rest. From experience acquired during the last 15 years, we argue that EIIS represents a broad spectrum of abnormalities and that video-recorded continuous laryngoscopy performed during maximal exercise (CLE-test) is required to make a correct diagnosis. EIIS strongly influences performance, and adequate diagnostic work-up and treatment is therefore important. Method: All patients presenting with EIIS to our institution are offered a complete maximal cardiopulmonary treadmill exercise test with a CLE set-up, MVV at rest with laryngoscopic surveillance and they fill in a standardized questionnaire. We here present findings from athletes with EIIS, competing at a national or international level, tested at our institution since 2012. Results: Thirty two (19%) of 164 new referrals were top athletes, 23 (72%) females. Almost all (97 %) felt that EIIS prevented them from reaching their goals, and 25% had stopped pushing themselves because of breathing problems. Seventy-four % had attempted asthma medication, and 54% stopped due to no effect. Breathing problems during low intensity exercise was reported by 10%, while 70% had problems during high intensity exercise, and 50 % had worse symptoms during competition. Despite similar symptoms, laryngeal findings varied. Moderate to severe supraglottic obstruction were seen in 69% with a secondary adduction of the vocal cords in 32%. Only 50% had moderate to severe supraglottic obstruction during MVV at rest, and 69% were able to describe this as an inspiratory problem or a problem with stridor. Primary exercise induced VCD was observed in one subject only. Epiglottic abnormalities was seen in 16%, seemingly disturbing airflow, and 80% of these had sense of being suffocated. Normal findings were seen in 18%, with symptoms probably explained by inadequate expectations or breathing patterns. Conclusion: The origins of EIIS in top athletes vary, and the symptoms influenced performance to a large extent. Adduction of supraglottic structures and not the vocal cords was the inciting event in the majority. EIIS is difficult to define based on symptoms alone or with laryngoscopy at rest. A correct diagnosis requires continuous laryngoscopy during exercise, which is a safe procedure revealing findings with therapeutic consequences.
© Copyright 2014 19th Annual Congress of the European College of Sport Science (ECSS), Amsterdam, 2. - 5. July 2014. Veröffentlicht von VU University Amsterdam. Alle Rechte vorbehalten.