Assessment of Mitral Valve Disease: A Review of Imaging Modalities

Abstract

Mitral valve disease (MVD) related to mitral valve prolapse (MVP), coronary artery disease (CAD), and calcific mitral stenosis, is increasing in prevalence across the USA and Europe in the context of a longer life expectancy and aging population. In developing countries, rheumatic heart disease remains a major cause of MVD. Echocardiography represents the primary diagnostic modality for assessment of the mitral valve (MV). With the implementation of three-dimensional imaging, echocardiography has become an indispensable tool to evaluate the morphology, geometry, and function of the MV apparatus in the pre-operative setting. However, recognition of its limitations and advances in newer technologies have led to a growing interest in other imaging modalities such as cardiac magnetic resonance (CMR). Although still not widely available, CMR is an essential complement to echocardiography, especially when poor image quality, significant variability in flow diameter measurements, and geometric assumptions of flow orifice preclude accurate quantification of mitral regurgitation on echocardiographic images. In addition, CMR can reliably provide quantitative determination of ventricular volumes and function, hence facilitating surgical decision-making when serial linear echocardiographic measurements are discrepant. Finally, CMR assessment of fibrosis using late gadolinium enhancement allows better understanding of the interactions between MVD and the myocardium in both MVP and MVD related to CAD or other myopathy. In this review, we summarize the role of the available imaging modalities in understanding valvular pathology and determining severity of regurgitation or stenosis. Recently published valvular guidelines highlight the importance of monitoring MVD progression and the shift to intervention earlier in the course of disease. In this context, we also discuss the potential role of echocardiography and CMR in identifying early stages of MVD and/or pre-clinical markers of myocardial dysfunction.

The mechanisms, diagnosis and management of mitral regurgitation in mitral valve prolapse and hypertrophic cardiomyopathy

“…73,81 Cardiac ultrasound provides information regarding valve morphology, severity of regurgitation, global and regional ventricular function and allows correlations between valve structure, biomechanics and haemodynamics. 73,5 The standard investigations for patient assessment with MVP are two-dimensional (2D) and Doppler echocardiography.…”

“…1,81,83 Regurgitation is considered severe in the setting of MVP when EROA is at least 40 mm 2 , RVol is at least 60 ml per beat and RF is at least 50%. LV dimensions can also be performed by means of TTE.…”

“…83 The role of transesophageal echocardiography MVP imaging obtained via TEE is of higher quality compared to TTE, as it provides better assessment of the etiology and quantification of the severity of MR. 35,81,87 It is preferred when TTE imaging is of poor quality or when complex, calcified or endocarditic lesions are being assessed. 1 This investigation is mainly used on inpatients and during interventions to evaluate lesions and to monitor surgical results.…”

“…1,81 3D TTE provides accurate data regarding anatomic localisation of prolapsing scallops, allowing better spatial localisation of commissures and quantification of MR severity. 81,89 3D multiplanar reconstruction (MPR) is a revolutionary echocardiography technique with an improved accuracy of MVP description compared to 2D investigations and the benefit of combining these two methods (3DMPR and 2DTTE) as part of the pre-operative investigations is increased.…”

“…3D TEE is superior to and has a distinct advantage over 2D TEE because imaging of the MV apparatus is more detailed and allows a more accurate localisation of prolapsing scallops 81,87,90 ( Figure 4). It has been shown that 3DTEE is comparable to cardiac magnetic resonance (CMR) regarding feasibility and accuracy of diagnosis.…”