Transthoracic echocardiography for arrhythmic mitral valve prolapse: Phenotypic characterization as first step

Abstract

Mitral valve prolapse (MVP) is the most frequent valvulopathy with a prevalence of 1.2%–2.4% in general population and it is characterized by a benign course. Although it can be associated with some complications, ventricular arrhythmias (VA) and sudden cardiac death (SCD) as ultimate expressions, are the most worrying. The estimated risk of SCD in MVP is between 0.2% and 1.9% per year including both MVP patients with left ventricular (LV) dysfunction due to severe MR and MVP patients without significant MR. The latter ones constitute a particular phenotype called “malignant MVP” characterized by bileaflet myxomatous prolapse, ECG repolarization abnormalities and complex VAs (c‐VAs) with polymorphic/right bundle branch block morphology (RBBB) and LV fibrosis of the papillary muscles (PMs) and inferobasal wall secondary to mechanical stretching visualized as late gadolinium enhancement (LGE) areas by cardiac magnetic resonance (CMR). In MVP, the first diagnostic approach is transthoracic echocardiography (TTE) that defines the presence of mitral annular disjunction (MAD) which seems to be associated with “arrhythmic MVP” (AMVP). From an ECG point of view, AMVP is characterized by frequent premature ventricular contractions (PVCs) arising from one or both PMs, fascicular tissue, and outflow tract, as well as by T‐wave inversion in the inferolateral leads. The aim of the present paper is to describe TTE red flags that could identify MVP patients at high risk to develop complex arrhythmias as supported by the corresponding findings of LGE‐CMR and anatomy studies. TTE could be a co‐partner in phenotyping high‐risk arrhythmic MVP patients.

Left Ventricle Segmental Longitudinal Strain and Regional Myocardial Work Index Could Help Determine Mitral Valve Prolapse Patients with Increased Risk of Ventricular Arrhythmias

“…At the same time, GLS was significantly augmented (more negative) in MAD+ (−22 (−23-−21)%) contrary to the MAD-group (−20 (−22-19)%, p = 0.027) with no differences regarding LVEF (56 (54-61)% vs. 58 (54-62)% respectively, p = 0.275). However, the GLS absolute values were similar between MVP and healthy persons; PSD values were significantly higher in MVP patients (44 (34-54) ms vs. 34 (27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38) ms respectively, p = 0.005), and in comparisons between each MVP group and control (Table 4). A more detailed analysis regarding the segmental parameters between MAD+, MAD−, and healthy groups revealed many differences were observed regarding segmental 2D STE parameters, particularly with increased (more negative) peak segmental strain values in the MAD+ group in basal posterior and mid (posterior, lateral and inferior) segments and increased MWI values in MAD+ group in mid posterior and inferior segments (Figures 5 and 6).…”

“…A robust technique that precisely assesses myocardium fibrosis is cardiac magnetic resonance (CMR) [3,29,30]. Since CMR is not a widespread diagnostic tool, finding noninvasive techniques easily performed in routine clinical practice, which could help identify MVP patients with a morphological substrate for VAs, is of great clinical importance [31]. Twodimensional (2D) transthoracic echocardiography is unquestionably the first-step imaging modality for MVP diagnosis, and assessing its structural characteristics [16,23,32].…”

Evaluation of left ventricular function in patients with mitral annular disjunction using speckle tracking echocardiography

“…Malignant MVP is characterized with increased SCD risk, bileaflet prolapse, ECG repolarization abnormalities, papillary muscle and inferobasal wall fibrosis and its main echo finding is MAD. This entity also includes another term arrhythmic MVP (AMVP) which usually presents with frequent premature ventricular contractions and T‐wave inversion in the inferolateral leads 12 . Although we did not define a subgroup as malignant MVP of AMVP, our results were compatible with the literature such that T‐wave inversion in the inferolateral leads was detected in 20.6% of MAD (+) group that was significantly more common than the MAD (−) group (4.3%) ( p = .014).…”

Mitral Valve Prolapse and Sudden Cardiac Death in Athletes at High Risk

“…Curling is the unusual hypermobile outward and downward systolic motion of the posterior mitral annulus on the adjacent myocardium. Both of them are eventually associated with relative hypertrophy and fibrosis of the adjacent myocardium and should be included in the description of MVP disease [ 18 , 19 ]. Importantly, MVP is a progressive disease.…”

“…), specific TTE red flags should be investigated to evaluate the arrhythmic risk in MVP. These are long redundant and prolapsing leaflets, MAD, systolic curling of the posterior MV annulus, high lateral S’ on TDI (> 16 cm/s, Pickelhaube Sign) and focal longitudinal strain [ 19 , 39 , 62 ]. In particular, MAD per se is considered a marker of AMVP but there is no consensus on cut-off severity.…”