| The cardiac catheterization
system enables virtually all minimally invasive
procedures in the catheterization lab. Current
systems all have the same fundamental architecture
using a point x-ray source that projects an x-ray beam through the patient and onto a large-area
detector, which converts the x-ray image to electrical
signals for display on a monitor. Current cardiac
catheterization systems capture a shadowgram image
of the patient.
 |
|
 |
| Conventional
cardiac catheterization system |
|
Conventional
system geometry |
Cardiac catheterization
systems perform two distinct types of real-time
x-ray imaging:
| • |
Diagnostic angiography
is performed with a high radiation exposure
in order to produce high-quality images. This
diagnostic (cine) mode produces images of
injected contrast agent flowing through the
coronary arteries to diagnose the initial
condition of the coronary arteries, determine
the intervention required, and re-evaluate
the coronary arteries after the intervention. |
| |
|
| • |
Interventional imaging
is performed with a regulated radiation exposure
that produces lower-quality images. This interventional
(fluoro) mode provides real-time imaging of
patient anatomy to guide the intervention
and is used when inserting devices into the
anatomy. The interventional mode is used for
approximately 90% of the procedure imaging
time. |
Comparison of Imaging
Modes for Cardiac Catheterization Systems
| |
Diagnostic
mode |
Interventional
mode |
| Common term |
Cine |
Fluoro |
| Primary
clinical use |
Diagnostic angiography |
Guide insertion and placement
of devices |
| Radiation
rate |
Higher (50-100 R/min) |
Lower (5-10 R/min) |
| Image quality |
Higher |
Lower |
| Imaging
time available |
Up to approximately 20 seconds |
Continuous |
| FDA radiation
rate limit |
None |
10 R/min
20 R/min (Optional high rate) |
|
