Assessment by autonomic blockade of age-related changes of the sinus node function and autonomic regulation in sick sinus syndrome

The American Journal of Cardiology
K KugaI Ito


Age-related changes of the sinus node (SN) function and the autonomic influence on the SN function were evaluated in 65 patients with sick sinus syndrome (range 14 to 84 years). Heart rate (HR), corrected SN recovery time and sinoatrial conduction time were measured before (basic) and after (intrinsic) autonomic blockade (propranolol 0.2 mg/kg plus atropine 0.04 mg/kg intravenously). Percent of autonomic chronotropies of the SN function were calculated by the following formulas: (1)--(intrinsic HR--basic HR/intrinsic HR) X 100; (2) (intrinsic corrected SN recovery time--basic corrected SN recovery time/intrinsic corrected SN recovery time) X 100; (3) (intrinsic sinoatrial conduction time--basic sinoatrial conduction time/intrinsic sinoatrial conduction time) X 100. Basic HR, basic corrected SN recovery time and basic sinoatrial conduction time did not vary with age. Intrinsic HR decreased with age, but this correlation was weak (r = -0.54, p less than 0.001). Intrinsic corrected SN recovery time and intrinsic sinoatrial conduction time tended to increase with age (r = 0.26, p less than 0.05; r = 0.29, p less than 0.05, respectively). Percent chronotropies of HR, corrected SN recovery time and sinoatrial conduction time were neg...Continue Reading


Oct 1, 1978·Circulation·O S NarulaJ W Linhart
Nov 1, 1976·Japanese Heart Journal·M SugiuraK Ueda
Mar 1, 1975·Archives of Internal Medicine·W J MandelK Obayashi
Jun 1, 1975·British Heart Journal·D J GoodmanD C Harrison
Apr 1, 1970·Cardiovascular Research·A D Jose, D Collison
Nov 1, 1971·Circulation Research·M N Levy
Feb 1, 1972·British Heart Journal·M J Davies, A Pomerance
Jun 1, 1984·International Journal of Cardiology·K K SethiM P Gupta
Aug 1, 1983·The American Journal of Medicine·M A PfeiferJ B Halter


May 1, 1994·Journal of Clinical Pharmacology·M A FreyW G Hoffler
Nov 30, 2000·Current Treatment Options in Cardiovascular Medicine·W J MandelH S Karagueuzian
Jan 17, 2012·Clinical Cardiology·Nihar R Desai, Robert P Giugliano

Related Concepts

Age Factors
Atropine Sulfate Anhydrous
Sympathetic Nerve Block
Autonomic Nervous System
Cardiac Pacing, Artificial
Electrophysiology (Science)
Pulse Rate
Sinus Node Dysfunction (Disorder)

Related Feeds

Cardiovascular Diseases: Risk Factors

Cardiovascular disease is a significant health concern. Risk factors include hypertension, obesity, dyslipidemia and smoking. Women who are postmenopausal are at an increased risk of heart disease. Here is the latest research for risk factors of cardiovascular disease.

Cardiac Conduction System

The cardiac conduction system is a specialized tract of myocardial cells responsible for maintaining normal cardiac rhythm. Discover the latest research on the cardiac conduction system here.