Comparative Imaging Assessment of Valvular Heart Disease

The objective of this study is to compare the accuracy of 3D TTE to 2D TTE in assessing the severity of valvular heart disease in patients with aortic stenosis, aortic regurgitation, and mitral valve regurgitation by comparing this to the reference standard of cardiac magnetic resonance (CMR) in subjects with different etiologies and mechanisms of valvular lesions and to the integrative method of valvular lesion grading as recommended by inter-societal guidelines. Another objective is to assess prevalence of focal and diffuse myocardial fibrosis as assessed by CMR in patients with aortic stenosis, aortic regurgitation and mitral regurgitation. In addition, the investigators aim to determine whether severity of myocardial fibrosis predicts onset of symptoms, referral for valve surgery and adverse ventricular remodeling. The investigators also aim to look at patients who will be undergoing CRT implant to predict their response to therapy.

At baseline, the Rapid Assessment of Physical Activity questionnaire and the Kansas City Cardiomyopathy Questionnaire will be completed. A 6-12 month follow-up is required and will include an abbreviated non-contrast research cardiac MRI and subject questionnaires.

Other follow-up will include using electronic medical records and the Social Security Death Index database for outcomes such as death, hospitalization for heart failure, mitral or aortic valve interventions and cardiovascular death.

Select patients will be asked to undergo a supine bicycle exercise stress MRI at enrollment. Approximately 40 subjects will be included in this substudy.

Additional exclusion criteria for this substudy:

* Unable to pedal a supine bicycle * Require supplemental oxygen

During the exercise stress MRI, patients will be asked to cycle on a supine bike that will be mounted on the MRI platform. During this test, a caregiver will be present. An electrocardiogram (ECG) will be used to obtain tracings of cardiac activity. Respirations, blood pressure, and heart rate are also monitored during exercise. The test is continued until peak exercise level or target heart rate is achieved. As soon as the exercise portion is complete, MRI images will be acquired. When the test is complete, patients will be monitored until ECG, heart rate, and breathing have returned to baseline. Patients will be assessed for symptoms such as chest pain, dyspnea, leg pain, dizziness, or fatigue and may be given medications or instructed to stop the test early as necessary.

• Accuracy of echocardiography as compared with MRI [Срок оценки: 6 Months]