Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Ultrasound molecular imaging of cardiovascular disease

Abstract

Myocardial contrast echocardiography utilizes intravenously injected gas-filled microspheres as acoustically active red blood cell tracers. During ultrasound imaging, unimpeded microsphere transit through the intramyocardial microcirculation causes transient myocardial opacification, which can be mapped and quantified as myocardial perfusion. Ultrasound molecular imaging utilizes similar acoustically active microspheres, which are modified to bear a receptor-specific ligand on the surface, conferring microsphere binding to a disease-specific endothelial epitope. Because the microspheres adhere to the endothelium, ultrasound imaging reveals a persistent, rather than transient, contrast effect, indicating the presence and location of the molecule of interest in real time. Molecular contrast echocardiography has been developed to detect upregulated leukocyte adhesion molecules during microvascular inflammation, such as occurs in cardiac transplant rejection and ischemia–reperfusion. Principles of microsphere targeting and ultrasound imaging of microvascular epitopes have been extended to larger vessels to image molecular markers of atherosclerosis. This Article summarizes the current status of cardiovascular ultrasound molecular imaging. Experimental proofs of concept will be outlined and the clinical extension of these concepts to the molecular imaging of cardiovascular disease using clinical ultrasound technology will be discussed.

Key Points

  • Ultrasound molecular imaging is based on the use of gas-filled microspheres engineered to bind to function-specific endothelial markers of disease via specific ligand-receptor interactions and that can be detected using clinical ultrasound scanning

  • Targeted ultrasound imaging of leukocyte adhesion molecules can be used clinically to noninvasively identify myocardial ischemic memory, angiogenesis, and acute heart transplant rejection

  • Catheter-based intravascular ultrasound imaging of adhesion molecules might permit identification of atherosclerosis-prone endothelium before luminal stenosis, facilitating early-stage diagnosis, and hence preventative treatment

  • Optimization of microbubble and transducer design holds promise for the clinical translation of ultrasound molecular imaging to human populations in the foreseeable future

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Basis for molecular imaging with microbubbles.
Figure 2: Color-coded short axis ultrasound images and the corresponding myocardial specimen of the left ventricle demonstrating imaging of ischemic memory in a rat undergoing transient coronary artery occlusion.
Figure 3: Ultrasound molecular imaging of early atherosclerosis in atherosclerosis-prone mice (ApoE deficient) fed a high-cholesterol diet.

Similar content being viewed by others

References

  1. Skyba DM et al. (1996) Hemodynamic characteristics, myocardial kinetics and microvascular rheology of FS-069, a second-generation echocardiographic contrast agent capable of producing myocardial opacification from a venous injection. J Am Coll Cardiol 28: 1292–1300

    Article  CAS  Google Scholar 

  2. Lindner JR et al. (2002) Microvascular rheology of Definity microbubbles after intra-arterial and intravenous administration. J Am Soc Echocardiogr 15: 396–403

    Article  Google Scholar 

  3. Demos SM et al. (1999) In vivo targeting of acoustically reflective liposomes for intravascular and transvascular ultrasonic enhancement. J Am Coll Cardiol 33: 867–875

    Article  CAS  Google Scholar 

  4. Lanza GM et al. (2000) In vivo molecular imaging of stretch-induced tissue factor in carotid arteries with ligand-targeted nanoparticles. J Am Soc Echocardiogr 13: 608–614

    Article  CAS  Google Scholar 

  5. Straub JA et al. (2007) AI-700 pharmacokinetics, tissue distribution and exhaled elimination kinetics in rats. Int J Pharm 328: 35–41

    Article  CAS  Google Scholar 

  6. Villanueva FS et al. (2001) Detection of coronary artery stenosis with power Doppler imaging. Circulation 103: 2624–2630

    Article  CAS  Google Scholar 

  7. Villanueva FS et al. (1998) Microbubbles targeted to intercellular adhesion molecule-1 bind to activated coronary artery endothelial cells. Circulation 98: 1–5

    Article  CAS  Google Scholar 

  8. Hamilton AJ et al. (2004) Intravascular ultrasound molecular imaging of atheroma components in vivo. J Am Coll Cardiol 43: 453–460

    Article  Google Scholar 

  9. Marsh JN et al. (2002) Improvements in the ultrasonic contrast of targeted perfluorocarbon nanoparticles using an acoustic transmission line model. IEEE Trans Ultrason Ferroelectr Freq Control 49: 29–38

    Article  Google Scholar 

  10. de Jong N et al. (2002) Basic acoustic properties of microbubbles. Echocardiography 19: 229–240

    Article  Google Scholar 

  11. Becher H and Burns PN (2000) Handbook of Contrast Echocardiography. New York: Springer-Verlag

    Google Scholar 

  12. Jayaweera AR et al. (1994) In vivo myocardial kinetics of air-filled albumin microbubbles during myocardial contrast echocardiography. Comparison with radiolabeled red blood cells. Circ Res 74: 1157–1165

    Article  CAS  Google Scholar 

  13. Hundley WG et al. (1998) Administration of an intravenous perfluorocarbon contrast agent improves echocardiographic determination of left ventricular volumes and ejection fraction: comparison with cine magnetic resonance imaging. J Am Coll Cardiol 32: 1426–1432

    Article  CAS  Google Scholar 

  14. Wei K et al. (2005) Detection of coronary stenoses at rest with myocardial contrast echocardiography. Circulation 112: 1154–1160

    Article  Google Scholar 

  15. Elhendy A et al. (2004) Comparative accuracy of real-time myocardial contrast perfusion imaging and wall motion analysis during dobutamine stress echocardiography for the diagnosis of coronary artery disease. J Am Coll Cardiol 44: 2185–2191

    Article  Google Scholar 

  16. Ragosta M et al. (1994) Microvascular integrity indicates myocellular viability in patients with recent myocardial infarction. New insights using myocardial contrast echocardiography. Circulation 89: 2562–2569

    Article  CAS  Google Scholar 

  17. Dwivedi G et al. (2007) Prognostic value of myocardial viability detected by myocardial contrast echocardiography early after acute myocardial infarction. J Am Coll Cardiol 50: 327–334

    Article  Google Scholar 

  18. Wei K et al. (2003) Comparison of usefulness of dipyridamole stress myocardial contrast echocardiography to technetium-99m sestamibi single-photon emission computed tomography for detection of coronary artery disease (PB127 Multicenter Phase 2 Trial results). Am J Cardiol 91: 1293–1298

    Article  Google Scholar 

  19. Lindner JR et al. (2001) Ultrasound assessment of inflammation and renal tissue injury with microbubbles targeted to P-selectin. Circulation 104: 2107–2112

    Article  CAS  Google Scholar 

  20. Weller GE et al. (2003) Ultrasound imaging of acute cardiac transplant rejection with microbubbles targeted to intercellular adhesion molecule-1. Circulation 108: 218–224

    Article  Google Scholar 

  21. Weller GE et al. (2005) Ultrasonic imaging of tumor angiogenesis using contrast microbubbles targeted via the tumor-binding peptide arginine-arginine-leucine. Cancer Res 65: 533–539

    CAS  PubMed  Google Scholar 

  22. Leong-Poi H et al. (2003) Noninvasive assessment of angiogenesis by ultrasound and microbubbles targeted to alpha(v)-integrins. Circulation 107: 455–460

    Article  CAS  Google Scholar 

  23. Leong-Poi H et al. (2005) Assessment of endogenous and therapeutic arteriogenesis by contrast ultrasound molecular imaging of integrin expression. Circulation 111: 3248–3254

    Article  CAS  Google Scholar 

  24. Ellegala DB et al. (2003) Imaging tumor angiogenesis with contrast ultrasound and microbubbles targeted to alpha(v)beta3. Circulation 108: 336–341

    Article  Google Scholar 

  25. Villanueva FS et al. (2007) Myocardial ischemic memory imaging with molecular echocardiography. Circulation 115: 345–352

    Article  Google Scholar 

  26. Wang J et al. (2005) Vascular endothelial growth factor-conjugated ultrasound microbubbles adhere to angiogenic receptors [abstract #U562]. Circulation 112: II-501

    Google Scholar 

  27. Rychak JJ et al. (2006) Selectin ligands promote ultrasound contrast agent adhesion under shear flow. Mol Pharm 3: 516–524

    Article  CAS  Google Scholar 

  28. Weller GE et al. (2002) Modulating targeted adhesion of an ultrasound contrast agent to dysfunctional endothelium. Ann Biomed Eng 30: 1012–1019

    Article  Google Scholar 

  29. Weller GE et al. (2005) Targeted ultrasound contrast agents: in vitro assessment of endothelial dysfunction and multi-targeting to ICAM-1 and sialyl Lewisx. Biotechnol Bioeng 92: 780–788

    Article  CAS  Google Scholar 

  30. Klibanov AL (2006) Microbubble contrast agents: targeted ultrasound imaging and ultrasound-assisted drug-delivery applications. Invest Radiol 41: 354–362

    Article  Google Scholar 

  31. Libby P (2002) Inflammation in atherosclerosis. Nature 420: 868–874

    Article  CAS  Google Scholar 

  32. Simons M (2005) Angiogenesis: where do we stand now? Circulation 111: 1556–1566

    Article  Google Scholar 

  33. Kaul S (2001) Myocardial contrast echocardiography: basic principles. Prog Cardiovasc Dis 44: 1–11

    Article  CAS  Google Scholar 

  34. Kaufmann BA et al. (2007) Molecular imaging of inflammation in atherosclerosis with targeted ultrasound detection of vascular cell adhesion molecule-1. Circulation 116: 276–284

    Article  CAS  Google Scholar 

  35. Rychak JJ et al. (2006) Deformable gas-filled microbubbles targeted to P-selectin. J Control Release 114: 288–299

    Article  CAS  Google Scholar 

  36. Dayton PA et al. (2001) Optical and acoustical dynamics of microbubble contrast agents inside neutrophils. Biophys J 80: 1547–1556

    Article  CAS  Google Scholar 

  37. Lankford M et al. (2006) Effect of microbubble ligation to cells on ultrasound signal enhancement: implications for targeted imaging. Invest Radiol 41: 721–728

    Article  Google Scholar 

  38. Zhao S et al. (2007) Selective imaging of adherent targeted ultrasound contrast agents. Phys Med Biol 52: 2055–2072

    Article  CAS  Google Scholar 

  39. Borden MA et al. (2006) Ultrasound radiation force modulates ligand availability on targeted contrast agents. Mol Imaging 5: 139–147

    Article  Google Scholar 

  40. Goertz DE et al. (2006) Contrast harmonic intravascular ultrasound: a feasibility study for vasa vasorum imaging. Invest Radiol 41: 631–638

    Article  Google Scholar 

Download references

Acknowledgements

FS Villanueva and WR Wagner are supported by grants from the NIH.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Flordeliza S Villanueva.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Villanueva, F., Wagner, W. Ultrasound molecular imaging of cardiovascular disease. Nat Rev Cardiol 5 (Suppl 2), S26–S32 (2008). https://doi.org/10.1038/ncpcardio1246

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ncpcardio1246

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing