Review ArticleIntracardiac Echocardiography: Newest Technology*
Section snippets
INTRODUCTION
Cardioscopy, or visualizing from within the heart and its conduits, has fascinated scientists and clinicians for decades.1, 2, 3 Ingenious methods have been used with limited success; however, only with the advent of invasive ultrasonography has actual visual navigation within the beating heart and vascular tree been possible.4, 5 Ultrasonography permits visualization not only of the vascular cavity and its walls but also across the walls and into surrounding contiguous structures. The physics
HISTORY
Cardioscopy devices were first proposed in the early 1920s.1, 6 One such early device consisted of a tube fitted with a glass or plastic window and illuminated by incident or transmitted light. The window was pressed against the cardiac structures being evaluated to eliminate blood from the field of view. Such tools were designed to perform limited surgical procedures such as mitral commissurotomy.6 Fiberoptics also were used to visualize within the heart;3, 7 however, this technique could be
TODAY
With advances in technology such as miniaturization of low-frequency transducers capable of enhanced tissue penetration, intracardiac imaging has become a clinical tool. Today, 2 introductory technologies have been used in human beings: (1) 9F (3.2-mm diameter), 9-MHz rotating ultrasound element catheter (EP Technologies, Boston Scientific Corp; San Jose, Calif)24 and (2) 10F (3.2-mm diameter), 5.5- to 10-MHz (ie, frequency agile), Doppler-capable vector phased-array ultrasound-tipped catheter
TOMORROW
Realization of the potential applications of intracardiac echocardiography depends on our ability to reduce the limitations of today’s technology. Current technology is unable to provide a wide field of view, which would facilitate user orientation within the heart and enhance navigation. Rotational (fan or toroidal),40 elevation defocusing,41 multiplane,42 and higher-dimensional transducer arrays have been proposed to expand the visual field (Figure 7).
CONCLUSION
With advances in technology, including miniaturization of low-frequency transducers capable of enhanced tissue penetration, intracardiac imaging is now a clinical tool. With the introduction of the newest 5.5- to 10-MHz phased-array transducer (with full Doppler capability) mounted on a 10F catheter, intracardiac echocardiography has the potential to play an important role in diagnostic and therapeutic interventional procedures. The clinical application of these current devices in cardiology
References (42)
- et al.
Video-assisted cardioscopy in congenital heart operations
Ann Thorac Surg
(1994) - et al.
Ultrasound cardioscopy: embarking on a new journey
Mayo Clin Proc
(1996) - et al.
Direct imaging of the tricuspid valve annular motions by fiberoptic cardioscopy in dogs: I. does De Vega’s annuloplasty preserve the annular motions?
J Thorac Cardiovasc Surg
(1992) - et al.
Transvenous intracardiac echocardiography
Am J Cardiol
(1981) - et al.
Quantitative assessment of stenotic aortic valve area by using intracardiac echocardiography: in vitro validation and initial in vivo illustration
Am Heart J
(1996) - et al.
Usefulness of intracardiac echocardiography in complex transseptal catheterization during percutaneous transvenous mitral commissurotomy
Mayo Clin Proc
(1996) - et al.
Usefulness of intracardiac echocardiography in transseptal puncture during percutaneous transvenous mitral commissurotomy
Am J Cardiol
(1993) - et al.
Intracardiac echocardiographic imaging of cardiac abnormalities, ischemic myocardial dysfunction, and myocardial perfusion: studies with a 10 MHz ultrasound catheter
J Am Soc Echocardiogr
(1993) - et al.
Intracardiac echocardiography without fluoroscopy: potential of a balloon-tipped, flow-directed ultrasound catheter
Am Heart J
(1995) - et al.
Intracardiac echocardiography-guided biopsy of intracardiac masses
J Am Soc Echocardiogr
(1995)
Intracardiac ultrasound detection of right ventricular infarction in a canine model
J Am Soc Echocardiogr
Intracardiac echocardiography with a steerable low-frequency linear-array probe for left-sided heart imaging from the right side: experimental studies
J Am Soc Echocardiogr
Intracardiac Doppler Hemodynamics and flow: new vector phased array ultrasound tipped catheter
Am J Cardiol
Intracardiac echocardiography during radiofrequency catheter ablation of cardiac arrhythmias in humans
J Am Coll Cardiol
Anatomy of atrioventricular nodal reentry investigated by intracardiac echocardiography
Am J Cardiol
In vitro quantification of radiofrequency ablation lesion size using intracardiac echocardiography in dogs
Am J Cardiol
Biophysical characteristics of radiofrequency lesion formation in vivo: dynamics of catheter tip-tissue contact evaluated by intracardiac echocardiography
Am Heart J
Potential of intracardiac ultrasonography as an adjunct for mapping and ablation
Am Heart J
Potential applications of intracardiac echocardiography in interventional electrophysiology
Am Heart J
Imaging technique and clinical utility for electrophysiologic procedures of lower frequency (9 MHz) intracardiac echocardiography
Am J Cardiol
Toroidal geometry: novel three-dimensional intracardiac imaging with a phased-array transducer
J Am Soc Echocardiogr
Cited by (0)
- *
Reprint requests: James B. Seward, MD, Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905.