Ventricular and dual chamber pacing for treatment of carotid sinus syndrome.

Thirty-nine consecutive patients with recurrent syncope and either cardioinhibitory or mixed type carotid sinus syndrome were studied to determine the efficacy of ventricular (VVI) pacing in 16, and dual chamber (DDD/DVI) in 23 patients. Only those patients affected by the isolated vasodepressor form were excluded. Follow-up lasted 12 +/- 5 months. Symptoms were totally eliminated in 67% of patients and ameliorated with persistence of minor symptoms in 33%. All patients underwent an initial 2-month follow-up in the VVI mode. Evaluation of the 19 patients who remained symptomatic and the 20 who became asymptomatic with VVI pacing demonstrated that factors observed prior to pacemaker implant were related to failure of the VVI mode. These included symptomatic pacemaker effect (42% vs 0%), mixed carotid sinus syndrome (95% vs 65%), orthostatic hypotension (47% vs 15%), or ventriculoatrial conduction (68% vs 38%). In the 23 patients with dual chamber pacing, random 2 month comparisons were performed between VVI and DVI/DDD pacing. The dual chamber mode was preferred by 14 patients, none preferred the VVI mode and nine noted no difference. Comparison of the two groups found that the factors linked to DVI/DDD preference were symptomatic pacemaker effect (50% vs 0%), ventriculoatrial conduction (78% vs 44%), or orthostatic hypotension (50% vs 11%). VVI pacing is efficacious in a high proportion of patients affected by cardioinhibitory or mixed carotid sinus syndrome. The identification of causes of VVI pacing failure allows determination of those who will benefit from VVI pacing and those who should have DVI/DDD. VVI pacing is suggested for the cardioinhibitory type with no symptomatic pacemaker effect and for the mixed type with no symptomatic pacemaker effect or orthostatic hypotension or ventriculoatrial conduction. Dual chamber pacing should be used in all other instances.

The effect of early bladder stimulation on spinal shock: a preliminary report.

The period of spinal shock which frequently follows spinal cord injury is associated with bladder areflexia and urinary retention. We studied the effect of early bladder electric stimulation on detrusor activity during the spinal shock phase in the dog. The animals had a spinal cord section at T10 vertebra and their bladder management was assigned to one of the three following groups: intermittent catheterization, indwelling catheterization and electric bladder stimulation. The parameters for evaluating each treatment included: blood chemistry, radiographic and urodynamic tests. The salient feature was the early return of detrusor activity in the group of animals treated by early electric stimulation of the bladder.

Natural and unnatural history of patients with severe carotid sinus hypersensitivity: a preliminary study.

Natural history of patients with symptomatic severe carotid sinus hypersensitivity is not clearly known. In order to evaluate the effectiveness of pacing therapy in these patients we performed a randomized treatment/no-treatment prospective study in 35 patients. They were randomly assigned to two groups: 19 patients received no therapy, 16 patients received a VVI (#11) or DDD (#5) pacemaker implant. During the 8.4 +/- 4.3 month follow-up period patients receiving no therapy had recurrence of syncope in 9 cases (47%) and minor symptoms in 13 (68%); at the 16th month, actuarial curve showed absence of syncope in 36% of patients and of any symptoms in 30%. During the 7.2 +/- 4.1 month follow-up period, the patients receiving the pacemaker implant had no recurrence of syncope, minor symptoms in three (19%); at the 16th month, actuarial curve showed absence of syncope in 100% of patients and of any symptoms in 78%. During follow-up, 12 patients in no-treatment group received a pacemaker implant because of the recurrence of severe symptoms; successively they had a strong reduction of symptoms. In conclusion, this study definitively demonstrates that patients with severe symptomatic carotid sinus hypersensitivity had a high rate of recurrence of spontaneous symptoms and that in these patients cardiac pacing is a useful therapy.

Assessment of VVI diagnostic pacing mode in patients with cardioinhibitory carotid sinus syndrome.

In this study, we used Holter pacemakers in a group of 13 patients affected by severe carotid sinus syndrome in order to evaluate its evolution. All the patients had one to three syncopal episodes and frequent other symptoms such as fainting, dizziness, lightheadedness and pre-syncope interferring with their daily activity so that pacemaker therapy was considered necessary. Patient selection criteria were: presence of the isolated cardioinhibitory type, absence of associated sinus dysfunction and absence of symptomatic VVI pacemaker effect. All the patients received a Micropacer 1 device; among special functions, bradycardia events counter was activated and programmed so that each sequence of three consecutive beats at a cycle length 1.5 sec (i.e., 4.5 sec total interval) could be recognized and stored in its memory. The follow-up lasted 13 +/- 7 months. Brady events occurred in eight out of 13 patients (62%), during this period. Syncope and major symptoms disappeared in all the patients; mild dizziness recurred rarely in two patients and were not linked to brady-events recording. In conclusion, disappearance of severe symptoms observed after pacemaker implant in cardioinhibitory carotid sinus syndrome seems to depend from pacing therapy, in most cases, yet from the benign natural course of the disease in some other cases.

Is DDD superior to VVI pacing in mixed carotid sinus syndrome? An acute and medium-term study.

The aim of this study was to evaluate the importance of atrial synchronism for pacing therapy of patients with mixed carotid sinus syndrome. In 23 patients (21 m, two f; mean age 69 +/- 8 years) affected by symptomatic mixed carotid sinus syndrome we performed: (1) Research of ventriculo-atrial conduction, orthostatic hypotension and pacemaker effect; and (2) Carotid sinus massage in the standing position during VVI and DVI temporary pacing. Next, all patients received a permanent DDD pacemaker and entered a 2 month two period single-blind, randomized, cross-over study on DVI/DDD versus VVI mode. During the DVI/DDD period, no syncope occurred in any patients, minor symptoms persisted in 11 (48%) of them; during VVI period syncopes recurred in three patients, symptoms requiring the withdrawal of VVI pacing and premature DVI/DDD reprogramming in eight patients, minor symptoms in 17 (74%). A comparison between 14 patients, who preferred DVI/DDD period (Group A), and the remaining nine patients who noted no preference between DVI/DDD and VVI period (Group B) was performed on the basis of the preimplant evaluation. Group A patients had a greater pacemaker effect (-34 +/- 16 mmHg vs -16 +/- 14 mmHg) and a higher prevalence of symptomatic pacemaker effect (50% vs 0%), of ventriculo-atrial conduction (78% vs 44%) and of orthostatic hypotension (50% vs 11%), while the entity of the systolic pressure fall caused by carotid sinus massage was similar in the two groups either during VVI mode (Group A -51 +/- 16 mmHg vs Group B -56 +/- 27 mmHg) or DVI mode (Group A -38 +/- 17 mmHg vs Group B -45 +/- 17 mmHg).(ABSTRACT TRUNCATED AT 250 WORDS)

Autonomic hyperreflexia, cesarean section and anesthesia. A case report.

Autonomic hyperreflexia, a potentially life-threatening condition, can appear during labor, delivery or cesarean section in a woman with a spinal cord injury. A case of autonomic hyperreflexia in a parturient was managed with regional neural blockade.

Effects of botulinum A toxin on detrusor-sphincter dyssynergia in spinal cord injury patients.

We evaluated the ability of low doses of botulinum A toxin, an inhibitor of acetylcholine release at the neuromuscular junction, to denervate and relax the spastic rhabdosphincter in 11 men with spinal cord injury and detrusor-sphincter dyssynergia. Toxin concentration, injection volume, percutaneous versus cystoscopic injection of the sphincter and number of injections were evaluated in 3 treatment protocols. All 10 patients evaluated by electromyography after injection showed signs of sphincter denervation. Bulbosphincteric reflexes in the 10 patients evaluated after injection were more difficult to obtain, and they showed a decreased amplitude and normal latency. The urethral pressure profile in the 7 patients in whom it was measured before and after treatment decreased an average of 27 cm. water after toxin injections. Post-void residual urine volume decreased by an average of 146 cc after the toxin injections in 8 patients. In the 8 patients for whom it could be determined toxin effects lasted an average of 50 days. The toxin also decreased autonomic dysreflexia in 5 patients.

The carotid sinus syndrome: a frequently overlooked cause of syncope in the elderly.

Exaggerated carotid sinus reflexes may account for alterations in consciousness responsible for significant disability and injury in elderly patients. Nonspecificity of symptoms and concomitant medical conditions frequently delay diagnosis and therapy. During a recent 9-year period, 82 patients were identified as having symptomatic carotid sinus hypersensitivity (CSH). Fifty-nine patients described complete syncope, 73 patients had multiple syncopal or near-syncopal episodes, and 40 patients related cervical pressure or motion as provocative events. Electrophysiologic testing demonstrated that 47% had cardioinhibitory CSH, 26% had vasodepressor CSH, and 27% had combined vasodepressor and cardioinhibitory CSH. The mean follow-up period of all patients was 36 months. Surgical therapy included ventricular demand pacemaker implantation in 33 patients and carotid sinus denervation in seven patients. Medical therapy was used in 32 patients, 11 mildly symptomatic patients were not treated, and 3 patients had carotid sinus irradiation. Pacemaker implantation relieved symptoms in 53%; however, 11 patients (33%) had significant postoperative complications. Carotid sinus denervation relieved symptoms in 86%, medical therapy in 54%, and carotid sinus irradiation in 33% of patients. Because of its demonstrated effectiveness in all variants of CSH and negligible perioperative morbidity, carotid sinus denervation should be offered to acceptable operative candidates when the diagnosis of CSH is confirmed.

Transplants of embryonic brainstem containing the locus coeruleus into spinal cord enhance the hindlimb flexion reflex in adult rats.

Cell suspensions of embryonic brainstem containing the locus coeruleus were injected intervertebrally into the lumbar spinal cord of adult rats whose descending catecholamine (CA) fibers had been lesioned with intracisternal injection of 6-hydroxydopamine. Up to 1100 CA cells were found 2 and 4 months later, and these cells grew processes which produced histologically detectable reinnervation of the lumbar gray matter on the injected side of the cord. To assess the functional activity of the transplanted CA cells, the force of the hindlimb flexion reflex was measured in acute spinal rats. This reflex has been shown previously to be strongly enhanced by catecholamines. The flexion reflexes were significantly stronger in the transplanted rats than in the controls. Further, the flexion reflexes were significantly reduced by phenoxybenzamine, an alpha-adrenergic blocker, in the transplanted rats while the reflexes of controls were not significantly changed. These results demonstrate that cell suspension transplants of embryonic brainstem containing the locus coeruleus into the adult rat spinal cord survive, grow reinnervating catecholamine processes, and can affect the functional activity of the spinal cord.

Management of a pregnant paraplegic patient in a rehabilitation center.

As the population of paraplegic women of child-bearing age increases, the psychiatrist may be more frequently called on to care for pregnant women. Pregnancy in a paraplegic patient can be accompanied by many serious medical problems including autonomic dysreflexia, anemia, decubitus ulcers, urinary tract infections, and premature labor. This is a case report of a successful pregnancy in a spinal cord injured woman who was managed at a rehabilitation center throughout her entire pregnancy, despite developing the multiple complications described above.

Preterm labor in the quadriplegic parturient.

The occurrence of preterm labor is not uncommon in the pregnant quadriplegic. Early diagnosis is hampered by the inability of most quadriplegics to sense uterine contractions in the usual way. A patient we recently treated for preterm labor learned to recognize contractions by the associated symptoms of autonomic hyper-reflexia: flushing, headache, and piloerection. Tocolytic therapy was successful and a favorable neonatal outcome occurred. Increased awareness by the physician and the pregnant quadriplegic patient is encouraged so that symptoms of autonomic hyper-reflexia may be recognized as potentially indicative of uterine contractions.

Transvesical phenolisation of the pelvic plexuses: a simple technique for the treatment of refractory detrusor instability and hyperreflexia.

A simple endoscopic technique for the infiltration of pelvic plexuses with phenol is described. The results suggest that this is a useful technique in the management of detrusor hyperreflexia and for the older patient with detrusor instability when standard conservative measures have failed. It is contraindicated in male patients because of the risk of impotence.

[Association of the carotid sinus syndrome and orthostatic hypotension. Another potential cause of the failure of VVI electrostimulation]. / L'associazione di sindrome del seno carotideo ed ipotensione ortostatica. Un'altra possibile causa di insuccesso dell'elettrostimolazione VVI.

The systolic blood pressure was measured during clinostatism and 15'', 1', 5' after standing in 101 patients with carotid sinus syndrome and in 101 controls matched for age, sex, and prevalence of organic heart disease. In the carotid sinus syndrome group we observed a greater systolic blood pressure reduction from the supine to standing position (20 +/- 19 vs 14 +/- 11 mmHg), a lower orthostatic pressure (111 +/- 23 vs 120 +/- 21 mmHg) and a greater incidence of orthostatic hypotension (defined as a blood pressure reduction greater than or equal to 50 mmHg or greater than or equal to 20 mmHg when orthostatic pressure was lower than 100 mmHg) (35% vs 17%). Twenty-three carotid sinus syndrome patients received a VVI pacemaker for control of their symptoms; after a mean follow-up of 12.2 +/- 7.7 months, unchanged or reduced symptoms persisted in 6 out 9 (67%) patients with previous orthostatic hypotension while only in 1 out of 14 (7%) patients without this feature. In conclusion, orthostatic hypotension is frequently associated with a carotid sinus syndrome and may account for relapses in some patients treated with VVI pacing.