Relation between myocardial oxygen consumption and myocardial blood volume: A study using myocardial contrast echocardiography

D. Elizabeth Le, Jian Ping Bin, Matthew P. Coggins, Kevin Wei, Jonathan R. Lindner, Sanjiv Kaul

    Research output: Contribution to journalArticle

    35 Scopus citations

    Abstract

    Myocardial blood volume (MBV) is the volume of blood residing in myocardial vessels, 90% of which is in capillaries. MBV can be measured in vivo using myocardial contrast echocardiography (MCE). It has been shown that when increases in coronary blood flow (CBF) are not associated with increase in myocardial oxygen consumption (MVO2), MBV does not increase. We hypothesized that MBV would increase when increases in CBF are associated with an increase in MVO2. The atrioventricular node was ablated in 18 dogs and dual-chamber pacing was instituted. In group 1 dogs (n = 9), heart rate was altered from 50 to 150 bpm-1 in increments of 20 bpm-1 in random order. In group 2 dogs (n = 9), heart rate was kept constant, and dobutamine was infused at doses of 5, 10, 20, 30, and 40 μg/kg-1/min-1. During each intervention, hemodynamic parameters and MVO2 were measured, and MCE was performed. MVO2 increased more (P < .01) with inotropic compared with chronotropic stimulation, resulting in a parallel increase in CBF. MBV fraction and MCE-derived myocardial blood flow increased significantly with increases in MVO2 (P < .05 and P < .001, respectively) when dobutamine was infused, but remained unchanged when heart rate alone was increased. We conclude that when MVO2 is increased substantially, the resulting increase in CBF and MCE-derived myocardial blood flow is mediated, in part, by an increase in MBV. Thus, capillary recruitment plays an important role in the physiologic regulation of CBF. Lack of increase in MBV during dobutamine stress may indicate the presence of coronary stenosis or microvascular disease.

    Original languageEnglish (US)
    Pages (from-to)857-863
    Number of pages7
    JournalJournal of the American Society of Echocardiography
    Volume15
    Issue number9
    DOIs
    StatePublished - Sep 2002

    ASJC Scopus subject areas

    • Radiology Nuclear Medicine and imaging
    • Cardiology and Cardiovascular Medicine

    Fingerprint Dive into the research topics of 'Relation between myocardial oxygen consumption and myocardial blood volume: A study using myocardial contrast echocardiography'. Together they form a unique fingerprint.

  • Cite this