The Role of Cardiovascular Magnetic Resonance in Patients with Mitral Regurgitation

Abstract

The 2019 Global Burden of Disease (GBD) study estimated that there were approximately 24.2 million people affected worldwide by degenerative mitral regurgitation (MR), resulting in 34,200 deaths. After aortic stenosis, MR is the most prevalent VHD in Europe and the second-most common VHD to pose indications for surgery in western countries. Current ESC and AHA/ACC guidelines for the management of VHD emphasize the importance of an integrative approach for the assessment of MR severity, which is of paramount importance in dictating the timing for surgery. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) are the first-line imaging modalities; however, despite the technological advancement, sometimes, the final diagnosis on the degree of the disease may still be challenging. In the last 20 years, CMR has emerged as a robust technique in the assessment of patients with cardiac disease, and, recently, its role is gaining more and more importance in the field of VHD. In fact, CMR is the gold standard in the assessment of cardiac volumes, and it is possible to accurately evaluate the regurgitant volume. The purpose of this review is to outline the current state-of-the-art management of MR by using Cardiac Magnetic Resonance (CMR).

Keywords: cardiovascular magnetic resonance; mitral valve.

Figure 1

CMR protocol to image a mitral valve. LA: Left atrium; LV: left ventricle; LVOT: left ventricle outflow tract.

Figure 2

A short axis view of the mitral valve with scallops. Contiguous, long-axis, left ventricular outflow tract SSFP images should be acquired to visualize and assess all the mitral valve cusps following the red lines (A). A three-chamber view of a patient with bileaflet mitral valve prolapse in systole (B) showing the regurgitant jet (red arrow). A three-chamber view showing the volume of the prolapse that is typically not considered when calculating the ejection fraction ((C), orange box). The mitral annular plane is highlighted in red lines. The slice position for the phase-contrast velocity mapping sequence (D). (E) is showing a flow curve (mL/s) through the ascending aorta to calculate the aortic forward flow. MRvol = mitral regurgitant volume; AFF = aortic forward flow; LVSV = left ventricle stroke volume.

Figure 3

CMR in a patient with MVP. MAD can be clearly diagnosed in an SSFP three-chamber view in the systole (red lines) (A). The presence of fibrosis on the tip of papillary muscles (red arrow) is highlighted in LGE (B); finally, higher levels of interstitial fibrosis can be identified by higher levels of native T1 mapping (C) and ECV after post-contrast T1 mapping (D).