Kuga K, Yamaguchi I, Sugishita Y
Department of Internal Medicine, University of Tsukuba, Ibaraki, Japan.
Jpn Circ J. 1993 Aug;57(8):760-8. doi: 10.1253/jcj.57.760.
To assess the relationship between aging and autonomic regulation of sinus node function, 56 subjects of various ages (range 14-75 years, mean 43 +/- 19 years) without sinus node disease were studied. Heart rate, corrected sinus node recovery time and sinoatrial conduction time were measured before (basic) and after (intrinsic) pharmacologic autonomic blockade (propranolol + atropine i.v.). Percent chronotropies of the above parameters were calculated by a modified Jordan's method. Basic heart rate and basic corrected sinus node recovery time did not vary with age (r = -0.15, r = 0.08, respectively), while basic sinoatrial conduction time tended to increase with age (r = 0.32, p < 0.05). Intrinsic heart rate decreased (r = -0.76, p < 0.001), and intrinsic corrected sinus node recovery time and intrinsic sinoatrial conduction time both increased with age (r = 0.55, p < 0.001; r = 0.56, p < 0.001, respectively). The younger the subject, the more negative the percent chronotropies of the above parameters were, and the percent chronotropies correlated positively with age (r = 0.68, p < 0.001; r = 0.52, p < 0.001 and r = 0.34, p < 0.05, respectively). In conclusion, intrinsic sinus node functions deteriorated with age. Furthermore, parasympathetic tone on the sinus node functions decreased with age, which may compensate for age-related deterioration of intrinsic sinus node function.
为评估衰老与窦房结功能自主调节之间的关系，我们对56名无窦房结疾病的不同年龄受试者（年龄范围14 - 75岁，平均43±19岁）进行了研究。在药物性自主神经阻滞（静脉注射普萘洛尔+阿托品）前后分别测量心率、校正窦房结恢复时间和窦房传导时间。上述参数的变时性百分比通过改良的乔丹方法计算。基础心率和基础校正窦房结恢复时间不随年龄变化（分别为r = -0.15，r = 0.08），而基础窦房传导时间随年龄增加（r = 0.32，p < 0.05）。固有心率下降（r = -0.76，p < 0.001），固有校正窦房结恢复时间和固有窦房传导时间均随年龄增加（分别为r = 0.55，p < 0.001；r = 0.56，p < 0.001）。受试者年龄越小，上述参数的变时性百分比越负，且变时性百分比与年龄呈正相关（分别为r = 0.68，p < 0.001；r = 0.52，p < 0.001和r = 0.34，p < 0.05）。总之，固有窦房结功能随年龄恶化。此外，窦房结功能的副交感神经张力随年龄降低，这可能补偿了与年龄相关的固有窦房结功能恶化。
