Real-time MRI Right Heart Catheterization Using Passive Catheters

* 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) Where\<TAB\>Scr 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