Tilt Table Training for Recurrent Syncope
abstract & commentary
Synopsis: Orthostatic training improved symptoms in adolescents with neurocardiogenic syncope unresponsive or intolerant to traditional pharmacologic therapy.
Source: Di Girolamo E, et al. Circulation 1999;100: 1798-1801.
Young adults with neurocardiogenic syncope often do not get relief or cannot tolerate traditional pharmacologic therapy. Thus, Di Girolamo and colleagues evaluated the use of a tilt table training program in a controlled trial of 47 adolescents (18 men, 29 women; mean age, 16 years) with recurrent head-up tilt test positive syncope refractory to traditional pharmacologic therapies. In 24 patients, orthostatic training was started in the hospital (5 sessions) and continued at home for one month. Hospital training consisted of daily tilt table sessions (60°) of incremental duration (10 minutes added each day) and home sessions consisted of standing against a wall twice a day for up to 40 minutes. Retesting at one month showed that 96% of the training patients were tilt negative as compared to 26% of the controls (P < 0.001). Di Girolamo et al concluded that orthostatic training improved symptoms in adolescents with neurocardiogenic syncope unresponsive or intolerant to traditional pharmacologic therapy.
Comment by Michael H. Crawford, MD
Recurrent syncope in a young adult is rarely life threatening, but it can significantly reduce quality of life. In my experience, it can limit job and school opportunities and cause serious psychological consequences, such as fostering dependency on parents or others. Although traditional pharmacologic therapy often works in my experience, the few refractory cases can be vexing. This report gives some hope for such patients.
This training program was simple and straightforward, but 40 minutes twice a day for an active teenager is a big commitment (remember trying to get the kids to practice piano?). Also, this study was done in Italy; five days of hospitalization to do daily tilt tests will not be feasible in the United States, but five sequential outpatient visits with tilt training would be. The exact training method may not be important and something adaptable to U.S. medicine could surely be devised.
Traditional pharmacologic therapy has included a wide variety of peripheral and centrally acting agents that affect the antonomic nervous system. Most popular have been beta blockers, alpha adrenergic vasoconstrictors, minerolocorticoids, and seratonin reuptake inhibitors. The patients in this study were refractory or intolerant to all four of these agents. Other approaches, such as disopyramide, theophylline, support hose, and cardiac pacing, are generally less successful and were not used in this study.
There are several limitations to this study. First, the patients were not randomized, training was offered to all, and only half consented. This tells you something about the popularity of such a time commitment despite the serious nature of the symptoms. The most enthusiastic and motivated were in the training group, which may explain the spectacular results. Thus, this approach, while effective, may not be widely applicable. Second, the mechanism of the training effect is unknown. The most likely explanation is desensitization of antonomic receptors, but other factors may also be important. In my experience, adolescents often "outgrow" neurocardiogenic syncope. The 18-month clinical follow-up in this study may have allowed this phenomenon to occur, since almost half the control group were asymptomatic during follow-up. Also, patients may change their lifestyle to avoid situations that cause syncope, and this was not controlled in the study. Finally, considerable variability in head-up tilt table testing has been observed in young adults including false-positive results in asymptomatic individuals. Despite these deficiencies in our knowledge about neurocardiogenic syncope, this report suggests that a noninvasive, nonpharmacologic approach may be effective therapy in selected patients.
Adolescents with neurocardiogenic syncope may benefit from:
a. psychological counseling.
b. job training.
c. orthostatic training.
d. physical conditioning.