Correlation Between an Impedance Cardiography Test for Decompensation and the Development of Left Ventricular Replacement Fibrosis

Inclusion Criteria: * • Male or female at least 18 years of age. * No prior history of myocardial infarction or cardiac amyloidosis. * Recent CMR scan with late gadolinium enhancement or scheduled for CMR scan with late gadolinium enhancement. * A history of: * Moderate aortic stenosis and no replacement fibrosis OR Moderate aortic stenosis and symptoms who has replacement fibrosis OR Severe aortic stenosis with replacement fibrosis prior to aortic valve replacement. * Able to comprehend and provide informed consent in English. * Participants must have intact, healthy skin at the electrode application sites. Exclusion Criteria: * • Under 18 years of age * Pregnant or breastfeeding women * Unable to consent * Prisoners * History of myocardial infarction * History of cardiac amyloidosis * Patients with any metal or implant such as IUD, braces, metal fragments implants in the eye, pacemakers (especially Minute Ventilation pacemakers with the MV function activated) defibrillators, or any other electronic cardiac implant. * Claustrophobic or afraid or small places. * Severe obesity (BMI \> 40) that impairs accurate ICG measurement due to difficulties in electrode placement or excessive impedance. * Active skin conditions, such as rashes, open wound or significant skin sensitivity at the electrode placement sites.