Systolic dysfunction of the subpulmonary left ventricle is associated with the severity of heart failure in patientswith a systemic right ventricle

Background: The study aimed to assess the relation between echocardiographic parameters of subpulmonary left ventricular (LV) size and function, and the severity of heart failure in patients with a systemic right ventricle (SRV). Methods and results: A total of 157 patients (89 post Mustard/Senning operations, 68 with congenitally corrected transposition of great arteries [ccTGA]) were included. The size and function of the SRV and subpulmonary LV were assessed on the most recent echocardiographic exam. Clinical data were collected from the electronic records. The majority (133, 84.7%) were in NYHA functional class 1-2. Median BNP concentration was 79.5[38.3-173.3] ng/l, and 100 (63.7%) patients were receiving heart failure therapy. Both LV and SRV fractional area change (FAC) differed significantly between patients with NYHA class 1-2 vs 3-4 (48[41.5-52.8]% vs 34[28.6-38.6]%, p < 0.0001 and 29.5[23-35]% vs 22[20-27]%, p < 0.0001, respectively), but LV FAC had a higher discriminative power for functional class >2 than SRV FAC (AUC 0.90, p < 0.0001 vs 0.79; p < 0.0001, respectively). A LV FAC cut-off value <39.2% had the highest accuracy in identifying patients with NYHA class 3-4 (sensitivity 83% and specificity 88%). In multivariable logistic regression analysis, LV FAC and SRV FAC independently associated to NYHA class 3-4 (OR 0.80 [95%CI 0.72-0.88], p < 0.0001 and OR 0.85 [95%CI 0.76-0.96], p= 0.007, respectively). Conclusions: Subpulmonary LV systolic dysfunction is associated with NYHA functional class 3-4 in patients with ccTGA or after Mustard or Senning operation. Careful evaluation of the subpulmonary LV should be a part of the routine assessment of patients with a SRV. (C) 2020 Elsevier B.V. All rights reserved.