Coronary autoregulation is abnormal in syndrome X: Insights using myocardial contrast echocardiography

Diana Rinkevich, Todd Belcik, Nandita C. Gupta, Elizabeth Cannard, Nabil Alkayed, Sanjiv Kaul

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Background: Syndrome X in women is thought to be caused by coronary microvascular dysfunction, the exact site of which is unknown. The aim of this study was to characterize the microvascular site of dysfunction in these patients using myocardial contrast echocardiography. Methods: Women with exertional angina, positive test results on stress imaging, but no coronary artery disease (the study group, n = 18) and age-matched control women also with no coronary artery disease (n = 17) were enrolled. Myocardial contrast echocardiography was performed at rest and during dipyridamole-induced hyperemia. Mean microbubble velocity (β) and myocardial blood volume (A) were measured, and myocardial blood flow (A · β) was computed. In addition, plasma concentrations of eicosanoids, female sex hormones, and C-reactive protein were measured. Results: Rest β and myocardial blood flow (A · β) were higher in the study compared with the control women (1.61 ± 0.68 vs 0.74 ± 0.44, P =.0001, and 157 ± 121 vs 54 ± 54, P = 0.0001, respectively) despite similar heart rates and systolic blood pressures. After the administration of dipyridamole, whereas the changes in A and A · β were not significantly different between the two groups, β reserve (the ratio of stress β to rest β) was markedly lower in the study group (1.48 ± 0.62 vs 2.78 ± 0.94, P =.0001). Blood hematocrit, eicosanoids, female sex hormones, glucose, and C-reactive protein were not different between the two groups. Conclusions: Coronary autoregulation is abnormal in patients with syndrome X (higher resting β and myocardial blood flow and lower β reserve), which suggests that the coronary resistance vessels are the site of microvascular abnormality.

Original languageEnglish (US)
Pages (from-to)290-296
Number of pages7
JournalJournal of the American Society of Echocardiography
Volume26
Issue number3
DOIs
StatePublished - Mar 2013

Fingerprint

Echocardiography
Homeostasis
Dipyridamole
Eicosanoids
Gonadal Steroid Hormones
C-Reactive Protein
Coronary Artery Disease
Blood Pressure
Microbubbles
Hyperemia
Blood Volume
Hematocrit
Coronary Vessels
Heart Rate
Glucose

Keywords

  • Coronary autoregulation
  • Myocardial contrast echocardiography
  • Syndrome X

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Cardiology and Cardiovascular Medicine

Cite this

Coronary autoregulation is abnormal in syndrome X : Insights using myocardial contrast echocardiography. / Rinkevich, Diana; Belcik, Todd; Gupta, Nandita C.; Cannard, Elizabeth; Alkayed, Nabil; Kaul, Sanjiv.

In: Journal of the American Society of Echocardiography, Vol. 26, No. 3, 03.2013, p. 290-296.

Research output: Contribution to journalArticle

@article{5ad25dccd1744a58941bde5abdf232a2,
title = "Coronary autoregulation is abnormal in syndrome X: Insights using myocardial contrast echocardiography",
abstract = "Background: Syndrome X in women is thought to be caused by coronary microvascular dysfunction, the exact site of which is unknown. The aim of this study was to characterize the microvascular site of dysfunction in these patients using myocardial contrast echocardiography. Methods: Women with exertional angina, positive test results on stress imaging, but no coronary artery disease (the study group, n = 18) and age-matched control women also with no coronary artery disease (n = 17) were enrolled. Myocardial contrast echocardiography was performed at rest and during dipyridamole-induced hyperemia. Mean microbubble velocity (β) and myocardial blood volume (A) were measured, and myocardial blood flow (A · β) was computed. In addition, plasma concentrations of eicosanoids, female sex hormones, and C-reactive protein were measured. Results: Rest β and myocardial blood flow (A · β) were higher in the study compared with the control women (1.61 ± 0.68 vs 0.74 ± 0.44, P =.0001, and 157 ± 121 vs 54 ± 54, P = 0.0001, respectively) despite similar heart rates and systolic blood pressures. After the administration of dipyridamole, whereas the changes in A and A · β were not significantly different between the two groups, β reserve (the ratio of stress β to rest β) was markedly lower in the study group (1.48 ± 0.62 vs 2.78 ± 0.94, P =.0001). Blood hematocrit, eicosanoids, female sex hormones, glucose, and C-reactive protein were not different between the two groups. Conclusions: Coronary autoregulation is abnormal in patients with syndrome X (higher resting β and myocardial blood flow and lower β reserve), which suggests that the coronary resistance vessels are the site of microvascular abnormality.",
keywords = "Coronary autoregulation, Myocardial contrast echocardiography, Syndrome X",
author = "Diana Rinkevich and Todd Belcik and Gupta, {Nandita C.} and Elizabeth Cannard and Nabil Alkayed and Sanjiv Kaul",
year = "2013",
month = "3",
doi = "10.1016/j.echo.2012.12.008",
language = "English (US)",
volume = "26",
pages = "290--296",
journal = "Journal of the American Society of Echocardiography",
issn = "0894-7317",
publisher = "Mosby Inc.",
number = "3",

}

TY - JOUR

T1 - Coronary autoregulation is abnormal in syndrome X

T2 - Insights using myocardial contrast echocardiography

AU - Rinkevich, Diana

AU - Belcik, Todd

AU - Gupta, Nandita C.

AU - Cannard, Elizabeth

AU - Alkayed, Nabil

AU - Kaul, Sanjiv

PY - 2013/3

Y1 - 2013/3

N2 - Background: Syndrome X in women is thought to be caused by coronary microvascular dysfunction, the exact site of which is unknown. The aim of this study was to characterize the microvascular site of dysfunction in these patients using myocardial contrast echocardiography. Methods: Women with exertional angina, positive test results on stress imaging, but no coronary artery disease (the study group, n = 18) and age-matched control women also with no coronary artery disease (n = 17) were enrolled. Myocardial contrast echocardiography was performed at rest and during dipyridamole-induced hyperemia. Mean microbubble velocity (β) and myocardial blood volume (A) were measured, and myocardial blood flow (A · β) was computed. In addition, plasma concentrations of eicosanoids, female sex hormones, and C-reactive protein were measured. Results: Rest β and myocardial blood flow (A · β) were higher in the study compared with the control women (1.61 ± 0.68 vs 0.74 ± 0.44, P =.0001, and 157 ± 121 vs 54 ± 54, P = 0.0001, respectively) despite similar heart rates and systolic blood pressures. After the administration of dipyridamole, whereas the changes in A and A · β were not significantly different between the two groups, β reserve (the ratio of stress β to rest β) was markedly lower in the study group (1.48 ± 0.62 vs 2.78 ± 0.94, P =.0001). Blood hematocrit, eicosanoids, female sex hormones, glucose, and C-reactive protein were not different between the two groups. Conclusions: Coronary autoregulation is abnormal in patients with syndrome X (higher resting β and myocardial blood flow and lower β reserve), which suggests that the coronary resistance vessels are the site of microvascular abnormality.

AB - Background: Syndrome X in women is thought to be caused by coronary microvascular dysfunction, the exact site of which is unknown. The aim of this study was to characterize the microvascular site of dysfunction in these patients using myocardial contrast echocardiography. Methods: Women with exertional angina, positive test results on stress imaging, but no coronary artery disease (the study group, n = 18) and age-matched control women also with no coronary artery disease (n = 17) were enrolled. Myocardial contrast echocardiography was performed at rest and during dipyridamole-induced hyperemia. Mean microbubble velocity (β) and myocardial blood volume (A) were measured, and myocardial blood flow (A · β) was computed. In addition, plasma concentrations of eicosanoids, female sex hormones, and C-reactive protein were measured. Results: Rest β and myocardial blood flow (A · β) were higher in the study compared with the control women (1.61 ± 0.68 vs 0.74 ± 0.44, P =.0001, and 157 ± 121 vs 54 ± 54, P = 0.0001, respectively) despite similar heart rates and systolic blood pressures. After the administration of dipyridamole, whereas the changes in A and A · β were not significantly different between the two groups, β reserve (the ratio of stress β to rest β) was markedly lower in the study group (1.48 ± 0.62 vs 2.78 ± 0.94, P =.0001). Blood hematocrit, eicosanoids, female sex hormones, glucose, and C-reactive protein were not different between the two groups. Conclusions: Coronary autoregulation is abnormal in patients with syndrome X (higher resting β and myocardial blood flow and lower β reserve), which suggests that the coronary resistance vessels are the site of microvascular abnormality.

KW - Coronary autoregulation

KW - Myocardial contrast echocardiography

KW - Syndrome X

UR - http://www.scopus.com/inward/record.url?scp=84874659680&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84874659680&partnerID=8YFLogxK

U2 - 10.1016/j.echo.2012.12.008

DO - 10.1016/j.echo.2012.12.008

M3 - Article

C2 - 23313388

AN - SCOPUS:84874659680

VL - 26

SP - 290

EP - 296

JO - Journal of the American Society of Echocardiography

JF - Journal of the American Society of Echocardiography

SN - 0894-7317

IS - 3

ER -