Cardiovascular reactivity of mitral valve prolapse patients during experimental stress exposure: evidence for a functional nature of cardiovascular symptoms.

We studied a group of 18 patients with mitral valve prolapse (MVP) and a group of 20 healthy controls. Subjects in both groups were subjected to a 1-h experimental stress exposure during which Holter-ECG monitoring was performed and was then continued for the following 24 h. MVP patients complained of significant cardiac palpitation during the stress session, but ECG examination did not reveal significant inter-group differences. However, the two groups did show statistically significant differences in some psychometric measurements (Toronto Alexithymia Scale, Anxiety Sensitivity Index, Fear Questionnaire, Beck Depression Inventory, and Harm Avoidance subscale of Tridimensional Personality Questionnaire) that underlie personality traits known to be important in the process fostering functional somatic symptoms, according to the somatosensory amplification model. As no objective signs of cardiac rhythm modification were found in MVP patients under stress, we postulate that the symptoms for which these patients were referred have a functional nature, and that there is no pathogenetic link with the underlying valvular defect.