The effects of voluntary hyperventilation on patients with chest pain without coronary artery disease

The present investigation was designed to examine panic symptom experience in patients with chest pain of nonorganic etiology, using a hyperventilation provocation procedure. Given the recent focus on panic disorder in patients with nonorganic chest pain, we assessed three indices of physiological arousal, subjective anxiety, and endorsement of DSM-III-R panic symptomatology in response to 3 min of voluntary hyperventilation. Subjects included 23 patients with nonorganic chest pain (CP sample) and matched normal controls (NC sample). The results indicate that hyperventilation produced significant increases in skin conductance, heart rate, and upper trapezious EMG in both CP and NC samples. Despite equivalent levels of physiological arousal and subjective anxiety, the CP sample endorsed a greater number of DSM-III-R panic symptoms relative to the NC sample. Examination of post-hyperventilation symptoms indicated that a greater percentage of the CP sample reported palpitations, nausea, and chest pain when compared with normals. Comparison of CP patients with and without Panic Disorder revealed no significant differences on any measure. The results suggests that hyperventilation plays a role in symptom experience in patients with nonorganic chest pain, although anxiety does not appear central in moderating this effect.