Insights in mitral annulus disjunction geometry, prevalence and extent in healthy subjects vs. patients with mitral valve prolapse and non-significant mitral regurgitation (RF_TH_214)

Thursday, January 30, 2025

2:00 PM – 2:10 PM East Coast USA Time

Location: Blue Room PreFunction

Presenting Author(s)

LT

Lara Tondi, MD

Cardiologist
University of Milan, Italy

Primary Author(s)

LT

Lara Tondi, MD

Cardiologist
University of Milan, Italy

Co-Author(s)

SM

Silvia Mantua, MD

Radiology Resident
Università degli Studi di Parma, Italy

Co-Author(s)

SM

Silvia Mantua, MD

Radiology Resident
Università degli Studi di Parma, Italy
GG

Gianluigi Guida, MD

Medical Doctor, Cardiologist
IRCCS Policlinico San Donato, Italy
EG

Eleonora Gnan, MD

Cardiology Resident
Università degli Studi di Milano, Italy
FG

Francesco Giangiacomi, MD

Cardiology Resident
Università degli Studi di Milano, Italy
AC

Antonia Camporeale, MD, PhD

Cardiologist
IRCCS Policlinico San Donato, Italy
AA

Andrea Attanasio, MD

Cardiologist
IRCCS Policlinico San Donato, Italy
GD

Giandomenico Disabato, MD

Cardiologist
IRCCS Policlinico San Donato, Italy
GC

Gianpaolo Carrafiello, MD

Professor of Radiology
Università degli Studi di Milano, Italy
PS

Pietro Spagnolo, MD

Medical Doctor, Radiologist
IRCCS Policlinico San Donato, Italy
ML

Massimo Lombardi, MD

Head of CMR Unit
IRCCS Policlinico San Donato, Italy

Background:

Mitral annulus disjunction (MAD) refers to the atrial displacement of the hinge point of the mitral annulus from the ventricular myocardium. Initially, MAD was linked to mitral valve prolapse (MVP) with potential arrhythmogenic implications. However, this anomaly has also been observed in a broader range of patients undergoing cardiac magnetic resonance (CMR) for various clinical indications, as well as in healthy individuals. Currently, there is no standardized method to assess the presence and extent of MAD, which likely consists of a variable circumferential alteration along the mitral annulus and the underlying ventricular myocardium. This study analyzed and compared the presence, extent, and geometry of MAD in MVP patients with non-significant mitral regurgitation (MR) and in healthy subjects.

Methods: 87 MVP patients with non-significant MR and 83 healthy subjects matched for age, sex, and body surface area, underwent CMR (Siemens Magnetom Aera 1.5 T) at IRCCS Policlinico San Donato (San Donato Milanese, Milan, Italy). MAD was defined as a separation ≥ 1.0 mm between the left atrial wall - mitral valve leaflet junction and the basal LV wall during end-systole. MAD presence and extent were assessed in all three standard cine views (3-ch, 2-ch and 4-ch). Additional reported parameters were MAD max (i.e. the maximum longitudinal displacement in any long-axis view), “true” MAD (i.e. evidence of MAD both in systole and diastole) and TAD (i.e. presence of tricuspid annular disjunction).

Results: Patients with MVP showed increased MAD extent in all views and higher MAD prevalence in 2ch posterior, 3ch and 4ch views, in comparison with healthy controls. Conversely, MAD prevalence in 2ch anterior location was similar between the two groups. MVP patients also showed a greater prevalence of TAD.
All results are reported in the Table and graphically resumed in the Figure.

Conclusion:

When evaluated in different views along the mitral annulus, MAD is found in a significant number of healthy individuals and in the majority of MVP patients with non-significant MR. In healthy subjects, the most common location for MAD is the anterior region of the 2-chamber view. In patients with MVP, MAD typically exhibits greater extensions and is more frequently observed also in the 2-ch posterior, 3-ch and 4-ch views. Further studies are needed to define a “pathologic MAD phenotype” and MAD clinical implications in and outside the context of MVP.