Thoracic sympathectomy and cardiopulmonary responses to exercise

Detection of the Stellate and Thoracic Sympathetic Chain Ganglia with High-Resolution 3D-CISS MR Imaging

BACKGROUND AND PURPOSE

Despite the importance of the sympathetic nervous system in homeostasis and its putative role in various disease states, little is known regarding our ability to image the sympathetic chain and sympathetic chain ganglia, perhaps owing to their small size. In this retrospective study, we sought to evaluate the normal anatomy of the sympathetic chain ganglia and assess the detectability of the sympathetic chain and sympathetic chain ganglia on high-resolution 3D-CISS images.

MATERIALS AND METHODS

This study included 29 patients who underwent 3D-CISS MR imaging of the thoracic spine for reasons unrelated to abnormalities of the sympathetic nervous system. Patients with a prior spinal operation or visible spinal pathology were excluded. The sympathetic chain ganglia were evaluated using noncontrast 3D-CISS MR imaging. Statistical analyses included t tests and measures of central tendency. The Cohen κ statistic was calculated to evaluate interrater reliability.

RESULTS

The stellate ganglion and thoracic chain ganglia were identified in all subjects except at the T10-T11 and T11-T12 levels. The stellate ganglion was found inferomedial to the subclavian artery and anterior and inferior to the transverse process of C7 in all subjects. Thoracic sympathetic chain ganglia were identified ventral to the costovertebral junction in all subjects from T2 to T10. There was strong interobserver agreement for the detection of the sympathetic chain ganglia with κ > 0.80. The size, shape, and location of these structures corresponded with gross anatomic and surgical observations.

CONCLUSIONS

The thoracic sympathetic chain ganglia can be identified on precontrast 3D-CISS MR imaging. This technique may aid in the initial evaluation of stellate ganglion and/or sympathetic chain ganglia size and signal change for comparison in future studies.

Thoracoscopic sympathectomy increases efferent cardiac vagal activity and baroreceptor sensitivity

OBJECTIVES

Thoracoscopic sympathectomy at levels T2 or T2-T3 is a treatment for focal hyperhidrosis and facial blushing. These levels of the sympathetic trunk innervate the heart, and consequently, the procedure is reported to change the heart rate variability due to changes in efferent cardiac autonomic activity. Our objective was to investigate the effects of thoracoscopic sympathectomy on global autonomic control, including baroreceptor sensitivity.

METHODS

Eight patients (6 F, median age 28 years [range 20-58 years]) were exposed to the tilt-table test and cardiopulmonary exercise test before, and 3 months after, thoracoscopic sympathectomy. Eight healthy age-, gender- and BMI-matched controls were used as controls and underwent the same tests once. During tilt-table testing electrocardiogram, blood pressure, impedance cardiography and respiration were measured continuously, and efferent cardiac autonomic balance was estimated.

RESULTS

The heart rate measured during orthostatic stress test was lowered after thoracoscopic sympathectomy (between-group; P = 0.01) due to a change in autonomic tone, with increased vagal (high-frequency power n.u.; P = 0.001), and reduced sympathetic efferent cardiac activity (low-frequency power n.u.; P < 0.001). Baroreceptor sensitivity measured during rest was increased (26 ± 13 vs 44 ± 19 ms/mmHg; P = 0.01), and diastolic blood pressure reduced after surgery (P = 0.01). The increases in systolic blood pressure and the sympathetic marker CCV-LF in response to orthostatic stress were higher before sympathectomy, with almost no increases post-surgically (condition × group interaction; P = 0.01 and P = 0.001, respectively). We found no change in post-procedure exercise capacity, although patients had a lower peak VO2 and maximal cardiac index than controls.

CONCLUSIONS

Thoracoscopic sympathectomy changes the autonomic tone towards increased vagal activity; this is potentially cardioprotective. To our knowledge, this is the first study to show increased baroreceptor sensitivity after thoracoscopic sympathectomy.

Incidence and frequency of endoscopic sympathectomy for the treatment of hyperhidrosis palmaris in Taiwan

Hyperhidrosis palmaris (HP) is a rather common disease in Taiwan. Taiwan is a leading nation in terms of the surgical treatment of this disease using thoracic endoscopic sympathectomy. However, the currently available epidemiological information regarding HP is insufficient. To date, the incidence of HP and the percentage of patients treated surgically have not been reported. We investigated the incidence of HP treated in 2004 by sampling Taiwan's National Health Insurance database. Patients who were diagnosed with HP during 2004 were identified by International Classification of Diseases, 9(th) Clinical Modification code 780.8 from a database of about 22 million beneficiaries, and were followed to 2006. Those who had been diagnosed as HP in 2002 or 2003 were excluded. Patients who underwent surgery were identified by the treatment codes 83026C (dorsal sympathectomy) and 83085B (transendoscopic dorsal sympathectomy, TES). Factors included in the analysis included age, sex, time of operation and hospitalization for surgery. In total, 15,839 patients with HP were identified. The incidence was 7.2 per 10,000 beneficiaries. The study sample included 7,603 males with an incidence of 6.9 per 10,000 beneficiaries, and 8,236 females with an incidence of 7.4 per 10,000 beneficiaries. The incidence was highest among patients aged 20-29 years old. The incidence decreased with increasing age (Mantel-Haenszel chi(2) test for trend, p < 0.001), and 3,755 cases (23.7%) received an operation, of which 1,733 were male (22.8% of all male patients) and 2,022 were female (24.6% of all female patients) (p = 0.009). Of these, 99.3% underwent transendoscopic dorsal sympathectomy, and 94.7% underwent surgery within 1 month of the initial diagnosis. Males underwent surgery sooner than females (p = 0.004). Adjusted multivariate logistic regression analysis showed that patients aged 20-29 were more likely to undergo surgery than the other age groups (odds ratio: 2.28; 95% confidence interval: 2.07-2.52). Regional hospitals had the highest chance to perform the operation (odds ratio: 4.87; 95% confidence interval: 4.41-5.37). Here, we have reported the incidence of HP in Taiwan in 2004 and concluded that the incidence was higher in females than in males. About one-quarter of patients underwent surgery, mostly within 1 month after attending an outpatient clinic; most surgical interventions involved endoscopic sympathectomy. This report fulfills the epidemiological information gap of HP and provides important data for future health care delivery.