L. Bernardi et al., INFLUENCE OF TYPE OF SURGERY ON THE OCCURRENCE OF PARASYMPATHETIC REINNERVATION AFTER CARDIAC TRANSPLANTATION, Circulation, 97(14), 1998, pp. 1368-1374
Citations number
31
Categorie Soggetti
Peripheal Vascular Diseas",Hematology,"Cardiac & Cardiovascular System
Background-Cardiac autonomic reinnervation after human cardiac transpl
antation has been demonstrated frequently but to date only for sympath
etic efferents. Standard surgical techniques leave many parasympatheti
c branches intact in the original atria and thus with less stimulus to
reinnervate the donor atria, Methods and Results-We used changes in t
he RR-interval power spectrum induced by sinusoidal modulation of arte
rial baroreceptors by neck suction at different frequencies to detect
both parasympathetic and sympathetic reinnervation in 79 subjects with
''standard'' and 10 ''bicaval'' heart transplants. In 24 subjects (17
standard and 7 bicaval), the protocol was repeated 6 and 11 months af
ter transplantation. Neck suction at 0.20 Hz produced a component at 0
.20 Hz in the RR-interval spectrum not due to respiration (fixed at 0.
25 Hz), which suggested parasympathetic reinnervation, in 4 of 10 bica
val but in only 2 of 79 standard transplant subjects (whose recipient
atria underwent >50% resection to remove scars of previous interventio
ns), P<.001. In only 1 (bicaval) transplant subject was parasympatheti
c reinnervation present 6 months after transplantation (confirmed 3 mo
nths later); in 4 subjects, it was absent at 6 months but appeared aft
er 11 months after transplantation. Atropine (0.04 mg/kg TV) abolished
the response to fast (0.20 Hz) and reduced that to slow stimulation,
confirming the presence of parasympathetic reinnervation (4 subjects),
Conclusions-Parasympathetic reinnervation depends on the surgical tec
hnique: because bicaval surgery cuts all sympathetic and parasympathet
ic nerves, regeneration might be stimulated similarly in both branches
, Standard surgery cuts only approximate to 50% of sympathetic fibers;
most recipient parasympathetic axons remain intact, hence their regen
eration might not be stimulated.