BENIGN PROGNOSIS OF EARLY SINUS NODE DYSFUNCTION AFTER ORTHOTOPIC CARDIAC TRANSPLANTATION

Previous reports raised concern about the prognosis of patients with s inus node (SN) dysfunction after cardiac transplantation and led to a low threshold for permanent pacemaker (PM) placement at most instituti ons, The present study addresses the survival inpatients with normal a nd impaired post operative SN function and tile effect of permanent pa cing with respect to overall and cardiac mortality. There were 120 pat ients with normal (corrected SN recovery time <520 ms, group I) and 47 patients with impaired SN function (corrected SN recovery time >520 m s and/or sinus arrest +/- escape rhythms). Pacing support was deemed u nnecessary in 23 of 47 patients with SN dysfunction (group II; asympto matic SN bradycardia and corrected SN recovery time 3,812 +/- 5,800 ms ) while a total of 24 patients had PM placement a mean of 29 +/- 44 da ys after transplantation (symptomatic bradycardia or absence of sinus rhythm at discharge, group III). Patients were followed for a mean of 46.7 months. Thirty-five deaths occurred during the study period. Sixt een deaths were cardiac but none were causally related to the SN dysfu nction (graft failure due to rejection or atheropathy n = 14; myocardi al infarction n = 2). Four of these cardiac deaths were sudden and all occurred in the presence of widespread structural abnormalities (reje ction/vasculopathy/myocardial infarction). SN dysfunction was not rela ted to overall (P = 0.25) or cardiac mortality (P = 0.33). Regarding e ither endpoint, patients who had permanent PM placement did no better than their unpaced counterparts in group II (P = 0.53 and P = 0.33, ov erall and cardiac mortality, respectively). Likewise, survival did not differ between groups I and III for either endpoint (P = 0.77, P = 0. 65, respectively). These data suggest that patients with mild SN abnor mality, who are in sinus rhythm at the time of discharge, can be follo wed by observation without specific therapy.