[Effect of radiotherapy on heart rate stability in cancer patients].
Heart rate variability at rest and in active orthostatic test (AOT), before and after radiotherapy (STD 3Gy; TTD 30Gy), was studied in 4 left-breast cancer patients and 8 cases of esophageal (middle third) cancer. AOT involved by decreased baroreflective activity (7) and parasympathetic reactivity. Sympathoadrenal fraction was relatively prominent in 6 patients against the background of average declined heart rate (3). Prior to radiotherapy, average heart rate was low in all patients, and continued to fall in 10 patients after treatment. While tumor process inhibited functional status and systemic reactions of adaptation, they were still further depressed by radiotherapy resulting eventually in failure of such response.
O N
ON
Simonova
S V
SV
Chudakov
L I
LI
Korytova
D000328:Adult; D000368:Aged; D017704:Baroreflex / Q000528:radiation effects; D001943:Breast Neoplasms / Q000532:radiotherapy*; D004938:Esophageal Neoplasms / Q000532:radiotherapy*; D005260:Female; D006339:Heart Rate / Q000528:radiation effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010275:Parasympathetic Nervous System / Q000528:radiation effects; D011878:Radiotherapy / Q000009:adverse effects