Real-time MRI Right Heart Catheterization Using Passive Catheters

Heart catheterization is a minimally invasive procedure to measure pressure and inject dye
into specific heart cavities. Heart catheterization usually uses X-ray guidance, which
involves radiation exposure and which fails to visualize soft tissue.

We have developed real-time magnetic resonance imaging (MRI) to guide heart catheterization
with tissue visualization but without X-ray radiation. In the first phase of this protocol we
showed that comprehensive right-sided heart catheterization is feasible in adult patients,
using commercially available MRI-compatible ( passive ) catheters.

In the second phase of the protocol, we began performing systematic right-sided heart
catheterization without X-ray whenever possible. We will assess the hearts response to
hemodynamic provocation during MRI catheterization tailored to the patient s problem. We will
use this protocol to further refine the technique

If successful, this will enable future testing of devices for adult and pediatric MRI-guided
catheterization, such as special active wire guides, which may lead to new non-surgical
treatments of cardiovascular disease.

- INCLUSION CRITERIA:

Age greater than or equal to 2 years old

Undergoing medically necessary diagnostic or interventional right and/or left
cardiovascular catheterization

EXCLUSION CRITERIA :

Cardiovascular instability including ongoing acute myocardial infarction, refractory angina
or ischemia, and decompensated congestive heart failure.

Women who are pregnant or nursing

Unable to undergo magnetic resonance imaging:

- Cardiac pacemaker or implantable defibrillator

- Cerebral aneurysm clip

- Neural stimulator (e.g. TENS-Unit)

- Any type of ear implant

- Ocular foreign body (e.g. metal shavings)

- Metal shrapnel or bullet.

- Any implanted device (e.g. insulin pump, drug infusion device), unless it is labeled
safe for MRI

EXCLUSION CRITERIA FOR GADOLINIUM-BASED CONTRAST AGENTS FOR ADULTS:

Renal excretory dysfunction, estimated glomerular filtration rate < 30 mL/min/1.73m(2) body
surface area according to the Modification of Diet in Renal Disease criteria

Glomerular filtration rate will be estimated using the CKD-EPI equation (33):

eGFR equal 141 x (minimum of (Scr/K, 1)(a) x (maximum of (Scr/K, 1)) (-1.209) x 0.993(Ag x
1.018 (if female) x 1.159 (if black)

WhereScr equal serum creatinine

a = -0.329 for females and -0.411 for males

k = 0.7 for females and 0.9 for males

Subjects meeting this exclusion criterion may still be included in the study but may not be
exposed to gadolinium-based contrast agents.

EXCLUSION CRITERIA FOR GADOLINIUM-BASED CONTRAST AGENTS FOR CHILDREN

Renal excretory dysfunction, estimated glomerular filtration rate < 30 mL/min/1.73m(2) body
surface area according to the Schwartz equation for estimation of GFR in children as
recommended by the National Kidney Disease Education Program. The Schwartz equation is
commonly used for GFR determination in children at Children s National Medical Center,
Washington, DC.

GFR (mL/min/1.73 m2) = (k (SqrRoot) height) / serum creatinine concentration where K =
constant defined as

follows:

k = 0.33 in premature infants [Excluded from this protocol]

k = 0.45 in term infants to 1 year of age [Excluded from this protocol]

k = 0.55 in children to 13 years of age

k = 0.70 in adolescent males (not females because of the presumed increase in male muscle
mass,

the constant remains 0.55 for females)

- Height in cm

- Serum creatinine in mg/dL