P1292 Prevalence and mechanisms of mitral regurgitation and its association with advanced heart failure in patients with a systemic right ventricle
Authors: Surkova E , Segura T , Dimopoulos K , Flick C , West C , Senior R , Gatzoulis M , Li W 
Published: January 2020

Abstract

Background
Although tricuspid regurgitation in patients with cardiac diseases is an established predictor of adverse outcomes, prevalence, mechanisms and clinical/prognostic value of non-systemic mitral regurgitation (MR) in patients with congenitally corrected transposition of great arteries (ccTGA) or simple transposition after Mustard or Senning procedures (TGA) are still poorly understood.

Purpose
To assess prevalence, mechanisms of MR and its association with severity of heart failure in patients with a systemic right ventricle (SRV).

Methods
From our digital echocardiographic database, we have identified all patients with a SRV who underwent echocardiography between 2014 and 2018. Severity of MR, size and function of SRV and subpulmonary LV were assessed from the latest echocardiographic studies.

Results
157 patients fulfilled inclusion criteria (89 post-Mustard/Senning, 68 ccTGA), median age 40.6 (33.1; 46.8) years, 57% male, median BNP 79.5 [38.3; 173.3] ng/l.
More than trivial MR was present in 44 (28.0%), further classified as mild, moderate and severe in 26 (16.6%), 15 (9.6%) and 3 (1.9%), respectively.
Principal mechanisms of MR included (i) device lead interference with the leaflet(s) in 26, (ii) organic pathology of mitral valve in 5 (2 prolapse, 2 cleft and 1 parachute mitral valve) and (iii) systolic leaflet(s) tethering ± annular dilatation in 4; no obvious cause of MR was identified in 10 patients.
Presence of more than trivial MR was significantly associated with NYHA class 3-4 (Chi-square 25.74, p &lt; 0.0001). Patients with MR also had higher BNP levels, larger LV with poorer systolic function and were more likely to have pulmonary stenosis (Table).
MR was less common in patients post-Mustard/Senning procedures compared to ccTGA (p &lt; 0.0001, Table); however, patients from the former group were more likely to have severe heart failure (Figure).

Conclusions
Non-systemic MR in patients with a SRV is relatively uncommon, but when present is associated with LV dilatation and systolic dysfunction, raised BNP levels, and heart failure symptoms. Predominant underlying mechanisms were device leads, organic pathology, and valve tethering. MR should be routinely assessed in SRV patients, particularly those with previous Mustard/Senning procedures, and be taken into account in decision making and timing interventions.
Characteristics of 157 patients with SRV Parameter No/trivial MR (N = 113) Mild-severe MR (N = 44) P value Age, years Mustard/Senning ccTGA Pulmonary stenosis NYHA class 3-4 ICD/Pacemaker lead 39.5 (33.1; 45.7) 75 (66%) 38 (34%) 13 (12%) 7 (6%) 31 (27%) 44.4 (32.7; 52) 14 (32%) 30 (68%) 12 (27%) 17 (39%) 32 (73%) 0.105 &lt;0.0001 &lt;0.0001 0.022 &lt;0.0001 &lt;0.0001 LV EDDi, cm/m2 LV FAC, % MAPSE, mm SRV EDAi, cm2/m&sup2; TAPSE, mm 2.11 (1.9; 2.45) 48 (42; 52.5) 18 (14; 22) 17.6 (15.0; 20.2) 12 (9; 15) 2.5 (2.0; 2.9) 40 (34; 48.8) 14.6 (11.5; 16.5) 17.5 (14.4; 22.2) 10.5 (9; 13) 0.0007 0.0011 0.0005 0.754 0.435 BNP 68 (35.3; 104.3) 177 (62.5; 345.3) &lt;0.0001 Values are reported as median (25th; 75th percentile) or n(%)
Abstract P1292 Figure. SRV patients with more than trivial MR