Skip to main content
NCBI home page
Heart logoLink to Heart
. 1997 Aug;78(2):117–126. doi: 10.1136/hrt.78.2.117

Myocardial oxygen supply:demand ratio as reference for coronary vasodilatory drug effects in humans.

I Vergroesen 1, J E Kal 1, J A Spaan 1, H B Van Wezel 1
PMCID: PMC484889  PMID: 9326983

Abstract

OBJECTIVE: Introduction and measurement of human myocardial oxygen supply:demand ratio as a reference for quantification of coronary microvascular vasodilating drug effects in clinical studies. Myocardial oxygen consumption is the major determinant of coronary blood flow; therefore, the true vasodilating properties of coronary vasodilating drugs that may have an effect on oxygen consumption cannot be correctly assessed from blood flow changes alone. DESIGN: Prospective, controlled trial. SETTING: Academic hospital. PATIENTS: 12 patients with multivessel coronary artery disease (CAD) undergoing coronary artery bypass grafting. INTERVENTIONS: Cardiac pacing at 30 beats/min above sinus rhythm in awake and anaesthetised patients (fentanyl/pancuronium bromide). MAIN OUTCOME MEASURES: Myocardial oxygen supply, defined as coronary sinus blood flow multiplied by arterial oxygen content; myocardial oxygen demand, defined as coronary sinus blood flow multiplied by arteriovenous oxygen content difference. The change in oxygen demand induced by pacing was related to the change in myocardial oxygen supply in awake and anaesthetised patients. This myocardial oxygen supply:demand ratio determined in the reference study was compared with that induced by intravenous and intracoronary drugs (nifedipine, felodipine, urapidil, and sodium nitroprusside) in two pharmacological studies: patients with CAD undergoing cardiac surgery (45 treated with sodium nitroprusside, 27 with nifedipine, and 27 with urapidil to manage arterial blood pressure); and patients with unstable angina (and a similar degree of CAD) undergoing cardiac catheterisation for diagnostic purposes (10 treated with intracoronary nifedipine and 10 with intracoronary felodipine). RESULTS: When awake, the ratio of pacing induced oxygen supply:demand changes in the 12 reference study patients was 1.50 (95% confidence intervals (CI), 1.41-1.58), similar to the 1.45 (1.35-1.56) measured in the same patients after induction of anaesthesia. Anaesthesia per se did not increase coronary oxygen supply above the expected increase related to demand changes. The only significant change in the oxygen supply:demand ratio was induced by intracoronary bolus administration of nifedipine and felodipine (10.6 (SE 1.9) and 13.9 (1.9) ml/min, respectively, above the demand related supply). CONCLUSIONS: Quantification of coronary vasoactive properties in relation to the physiological reference ratio between myocardial oxygen supply and demand may be a powerful tool to differentiate between true and apparent coronary vasoactive drugs.

Full text

PDF
117

Images in this article

119Image
on p.119

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Broten T. P., Feigl E. O. Role of myocardial oxygen and carbon dioxide in coronary autoregulation. Am J Physiol. 1992 Apr;262(4 Pt 2):H1231–H1237. doi: 10.1152/ajpheart.1992.262.4.H1231. [DOI] [PubMed] [Google Scholar]
  2. DeFily D. V., Chilian W. M. Coronary microcirculation: autoregulation and metabolic control. Basic Res Cardiol. 1995 Mar-Apr;90(2):112–118. doi: 10.1007/BF00789441. [DOI] [PubMed] [Google Scholar]
  3. Drake-Holland A. J., Laird J. D., Noble M. I., Spaan J. A., Vergroesen I. Oxygen and coronary vascular resistance during autoregulation and metabolic vasodilation in the dog. J Physiol. 1984 Mar;348:285–299. doi: 10.1113/jphysiol.1984.sp015110. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Feigl E. O. Coronary physiology. Physiol Rev. 1983 Jan;63(1):1–205. doi: 10.1152/physrev.1983.63.1.1. [DOI] [PubMed] [Google Scholar]
  5. Feigl E. O., Van Winkle D. M., Miyashiro J. K. Cholinergic vasodilatation of coronary resistance vessels in dogs, baboons and goats. Blood Vessels. 1990;27(2-5):94–105. doi: 10.1159/000158800. [DOI] [PubMed] [Google Scholar]
  6. Ganz W., Tamura K., Marcus H. S., Donoso R., Yoshida S., Swan H. J. Measurement of coronary sinus blood flow by continuous thermodilution in man. Circulation. 1971 Aug;44(2):181–195. doi: 10.1161/01.cir.44.2.181. [DOI] [PubMed] [Google Scholar]
  7. Jones C. J., Kuo L., Davis M. J., Chilian W. M. Myogenic and flow-dependent control mechanisms in the coronary microcirculation. Basic Res Cardiol. 1993 Jan-Feb;88(1):2–10. doi: 10.1007/BF00788525. [DOI] [PubMed] [Google Scholar]
  8. Kitamura K., Jorgensen C. R., Gobel F. L., Taylor H. L., Wang Y. Hemodynamic correlates of myocardial oxygen consumption during upright exercise. J Appl Physiol. 1972 Apr;32(4):516–522. doi: 10.1152/jappl.1972.32.4.516. [DOI] [PubMed] [Google Scholar]
  9. Koolen J. J., Van Wezel H. B., Piek J., van Liebergen R., Swaan A., Visser C. A. Effects of intracoronary felodipine versus nifedipine on left ventricular contractility and coronary sinus blood flow in stable angina pectoris. Am J Cardiol. 1994 Oct 1;74(7):730–732. doi: 10.1016/0002-9149(94)90320-4. [DOI] [PubMed] [Google Scholar]
  10. Kuo L., Davis M. J., Chilian W. M. Endothelium-dependent, flow-induced dilation of isolated coronary arterioles. Am J Physiol. 1990 Oct;259(4 Pt 2):H1063–H1070. doi: 10.1152/ajpheart.1990.259.4.H1063. [DOI] [PubMed] [Google Scholar]
  11. Mathey D. G., Chatterjee K., Tyberg J. V., Lekven J., Brundage B., Parmley W. W. Coronary sinus reflux. A source of error in the measurement of thermodilution coronary sinus flow. Circulation. 1978 Apr;57(4):778–786. doi: 10.1161/01.cir.57.4.778. [DOI] [PubMed] [Google Scholar]
  12. Meininger G. A., Davis M. J. Cellular mechanisms involved in the vascular myogenic response. Am J Physiol. 1992 Sep;263(3 Pt 2):H647–H659. doi: 10.1152/ajpheart.1992.263.3.H647. [DOI] [PubMed] [Google Scholar]
  13. Moffitt E. A., Sethna D. H. The coronary circulation and myocardial oxygenation in coronary artery disease: effects of anesthesia. Anesth Analg. 1986 Apr;65(4):395–410. [PubMed] [Google Scholar]
  14. Mohrman D. E., Feigl E. O. Competition between sympathetic vasoconstriction and metabolic vasodilation in the canine coronary circulation. Circ Res. 1978 Jan;42(1):79–86. doi: 10.1161/01.res.42.1.79. [DOI] [PubMed] [Google Scholar]
  15. Vergroesen I., Noble M. I., Wieringa P. A., Spaan J. A. Quantification of O2 consumption and arterial pressure as independent determinants of coronary flow. Am J Physiol. 1987 Mar;252(3 Pt 2):H545–H553. doi: 10.1152/ajpheart.1987.252.3.H545. [DOI] [PubMed] [Google Scholar]
  16. van Wezel H. B., Bovill J. G., Koolen J. J., Barendse G. A., Fiolet J. W., Dijkhuis J. P. Myocardial metabolism and coronary sinus blood flow during coronary artery surgery: effects of nitroprusside and nifedipine. Am Heart J. 1987 Feb;113(2 Pt 1):266–273. doi: 10.1016/0002-8703(87)90264-x. [DOI] [PubMed] [Google Scholar]
  17. van Wezel H. B., Bovill J. G., Koolen J. J., Patrick M. R., Fiolet J. W., van der Stroom J. G. Influence of glyceryl trinitrate and nifedipine on coronary sinus blood flow and global myocardial metabolism during coronary artery operation. Br Heart J. 1986 Sep;56(3):272–277. doi: 10.1136/hrt.56.3.272. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. van Wezel H. B., Bovill J. G., Visser C. A., Koolen J. J., Janse M. J., Meijne N. G., Barendse G. A., Floor L. M., Djamin R. Myocardial metabolism, catecholamine balance, and left ventricular function during coronary artery surgery: effects of nitroprusside and nifedipine. J Cardiothorac Anesth. 1987 Oct;1(5):408–417. doi: 10.1016/s0888-6296(87)96860-8. [DOI] [PubMed] [Google Scholar]
  19. van der Stroom J. G., van Wezel H. B., Vergroesen I., Kal J. E., Koolen J. J., Dijkhuis J. P., Swaan A., Porsius M., Kleinjans H. A., van Zwieten P. A. Comparison of the effects of urapidil and sodium nitroprusside on haemodynamic state, myocardial metabolism and function in patients during coronary artery surgery. Br J Anaesth. 1996 May;76(5):645–651. doi: 10.1093/bja/76.5.645. [DOI] [PubMed] [Google Scholar]

Articles from Heart are provided here courtesy of BMJ Publishing Group

RESOURCES