Effect of increases in cardiac contractility on cerebral blood flow in humans

Shigehiko Ogoh, Gilbert Moralez, Takuro Washio, Satyam Sarma, Michinari Hieda, Steven A. Romero, Matthew N. Cramer, Manabu Shibasaki, Craig G. Crandall

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

The effect of acute increases in cardiac contractility on cerebral blood flow (CBF) remains unknown. We hypothesized that the external carotid artery (ECA) downstream vasculature modifies the direct influence of acute increases in heart rate and cardiac function on CBF regulation. Twelve healthy subjects received two infusions of dobutamine [first a low dose (5 µg·kg-1·min-1) and then a high dose (15 µg·kg-1·min-1)] for 12 min each. Cardiac output, blood flow through the internal carotid artery (ICA) and ECA, and echocardiographic measurements were performed during dobutamine infusions. Despite increases in cardiac contractility, cardiac output, and arterial pressure with dobutamine, ICA blood flow and conductance slightly decreased from resting baseline during both low- and high-dose infusions. In contrast, ECA blood flow and conductance increased appreciably during both low- and high-dose infusions. Greater ECA vascular conductance and corresponding increases in blood flow may protect overperfusion of intracranial cerebral arteries during enhanced cardiac contractility and associated increases in cardiac output and perfusion pressure. Importantly, these findings suggest that the acute increase of blood perfusion attributable to dobutamine administration does not cause cerebral overperfusion or an associated risk of cerebral vascular damage. NEW & NOTEWORTHY A dobutamine-induced increase in cardiac contractility did not increase internal carotid artery blood flow despite an increase in cardiac output and arterial blood pressure. In contrast, external carotid artery blood flow and conductance increased. This external cerebral blood flow response may assist with protecting from overperfusion of intracranial blood flow.

Original languageEnglish (US)
Pages (from-to)H1155-H1161
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume313
Issue number6
DOIs
StatePublished - Dec 2017

Keywords

  • Blood pressure
  • Cardiac output
  • Dobutamine
  • External carotid artery
  • Internal carotid artery

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Effect of increases in cardiac contractility on cerebral blood flow in humans'. Together they form a unique fingerprint.

  • Cite this