Circadian control of human cardiovascular function

Endogenous circadian rhythms prepare the cardiovascular (CV) system for optimal function to match the daily anticipated behavioral and environmental cycles, including variable activities when awake during the day and recuperation when sleeping at night. The overall day-night patterns in most CV variables result from the summation of predictable circadian effects with variable behavioral and environmental effects on the CV system. The circadian system has also been implicated in the morning peak in the incidence of adverse CV events, including myocardial infarction, stroke, and sudden cardiac death. We discuss the resting and stress-reactive circadian control of CV physiology in humans and suggest future research opportunities, including improving CV therapy by optimally timing therapy relative to a person's internal body clock time.

Automated summary

Endogenous circadian rhythms play a role in optimizing cardiovascular function to match daily behavioral and environmental cycles, contributing to day-night patterns in cardiovascular variables. The circadian system is also implicated in the morning peak of adverse cardiovascular events. Future research opportunities include optimizing therapy timing relative to an individual's internal body clock to improve cardiovascular therapy outcomes.