Prognostic significance of subpulmonary left ventricular size and function in patients with a systemic right ventricle

AIMS

To assess the additional prognostic significance of echocardiographic parameters of subpulmonary left ventricular (LV) size and function in patients with a systemic right ventricle (SRV).

METHODS AND RESULTS

All adults with an SRV who underwent transthoracic echocardiography in 2010-18 at a large tertiary centre were identified. Biventricular size and function were assessed at the most recent examination. The study endpoint was all-cause mortality or heart/heart-lung transplantation. We included 180 patients, with 100 (55.6%) males, with a mean age of 42.4 ± 12.3 years, of whom 103 (57.2%) had undergone Mustard/Senning operations and 77 (42.8%) had congenitally corrected transposition of great arteries. Over 4.9 (3.8-5.7) years, 28 (15.6%) patients died and 4 (2.2%) underwent heart or heart-lung transplantation. Univariable predictors of the study endpoint included age, New York Heart Association functional Class III or IV, history of atrial arrhythmias, presence of a pacemaker or cardioverter defibrillator, high B-type natriuretic peptide, and echocardiographic markers of SRV and subpulmonary LV size and function. On multivariable Cox analysis of echocardiographic variables, indexed LV end-systolic diameter [ESDi; hazard ratio (HR) 2.77 (95% confidence interval, CI) 1.35-5.68, P = 0.01], LV fractional area change [FAC; HR 0.7 (95% CI 0.57-0.85), P = 0.002), SRV basal diameter [HR 1.66 (95% CI 1.21-2.29), P = 0.005], and SRV FAC [HR 0.65 (95% CI 0.49-0.87), P = 0.008] remained predictive of mortality or transplantation. On receiver-operating characteristic analysis, subpulmonary LV parameters performed better than SRV markers in predicting adverse events.

CONCLUSION

SRV basal diameter, SRV FAC, LV ESDi, and LV FAC are significantly and independently associated with mortality and transplantation in adults with an SRV. Accurate echocardiographic assessment of both SRV and subpulmonary LV is, therefore, essential to inform risk stratification and management.

Mechanical contraction patterns of the systemic right ventricle: a 3D echocardiography study

Funding Acknowledgements

Type of funding sources: None.

Background. In patients with transposition of great arteries (TGA) post atrial switch operation or with congenitally corrected TGA (ccTGA), the morphologically right ventricle (RV) has to adapt to the chronically increased systemic pressure.

Purpose. To investigate the functional adaptation of the systemic RV in patients with TGA post Mustard repair or ccTGA. 

Methods. RV volumes and EF were measured by 3D echocardiography in 33 patients with the systemic RV (21 TGA and 12 ccTGA; 45 ± 13y, 61% male), and in 33 healthy volunteers (44 ± 13y, 61% male). 

The 3D RV model was postprocessed by the ReVISION software and its contraction was decomposed along the longitudinal, radial and anteroposterior directions (Fig.A, Systemic RV in TGA) providing longitudinal, radial and anteroposterior EF (LEF, REF and AEF). Relative contribution of each component was measured as the ratio between LEF, REF and AEF to the global RVEF (LEFi, REFi and AEFi).

Results. Systemic RV was significantly larger with reduced function compared to controls (Tab). 3D RVEF demonstrated stronger correlation with BNP (Rho -0.76, p < 0.0001) compared to other parameters of RV function (free wall strain 0.55, p = 0.0083; FAC -0.47, p = 0.024; S’ -0.39 and TAPSE 0.06, p > 0.05).

While in healthy volunteers, all 3 components of RV systolic function contributed equally to the global RV EF, in patients with TGA the relative contribution of the anteroposterior component was dominant and differed significantly from longitudinal and radial components (AEFi 0.48 ± 0.06 vs LEFi 0.31 ± 0.07 vs REFi 0.36 ± 0.09, p < 0.0001)(Fig. B,C). In patients with ccTGA the longitudinal component was dominant and provided a relative compensation for the reduced anteroposterior and radial components (LEFi 0.47 ± 0.07 vs AEFi 0.34 ± 0.07, p = 0.0002 and vs REFi 0.36 ± 0.09, p = 0.0023)(Fig. B,C). Relative contribution of the radial contraction was significantly reduced in all systemic RV patients.

Conclusions. Systemic RV contraction patterns change significantly with anteroposterior contraction being dominant in patients with TGA post Mustard repair and longitudinal component being dominant in ccTGA.

3DE should be a part of routine assessment of the systemic RV, especially in TGA since no conventional echo parameters take into account anteroposterior RV contraction.

Parameters of RV systolic function Parameter Control group (N = 33) All SRV patients (N = 33) TGA (N = 21) ccTGA (N = 12) 3D EF, % 60 ± 3.8 36 ± 8.6* 34 ± 7.3* 38 ± 10* FAC, % 41.4 ± 3.7 25.9 ± 9.3* 25.1 ± 9.2* 27.1 ± 9.9* TAPSE, mm 24.6 ± 4.2 11.9 ± 3.9* 11.1 ± 2.9* 13.2 ± 5.1* RV free wall strain, % -32.5 ± 4.2 -14.5 ± 3.5* -14.5 ± 2.9* -15.5 ± 3.5* * p < 0.0001 Abstract Figure.

Systolic dysfunction of the subpulmonary left ventricle is associated with the severity of heart failure in patients with 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.

Hormone-Independent Mouse Mammary Adenocarcinomas with Different Metastatic Potential Exhibit Different Metabolic Signatures

The metabolic characteristics of metastatic and non-metastatic breast carcinomas remain poorly studied. In this work, untargeted Nuclear Magnetic Resonance (NMR) metabolomics was used to compare two medroxyprogesterone acetate (MPA)-induced mammary carcinomas lines with different metastatic abilities. Different metabolic signatures distinguished the non-metastatic (59-2-HI) and the metastatic (C7-2-HI) lines, with glucose, amino acid metabolism, nucleotide metabolism and lipid metabolism as the major affected pathways. Non-metastatic tumours appeared to be characterised by: (a) reduced glycolysis and tricarboxylic acid cycle (TCA) activities, possibly resulting in slower NADH biosynthesis and reduced mitochondrial transport chain activity and ATP synthesis; (b) glutamate accumulation possibly related to reduced glutathione activity and reduced mTORC1 activity; and (c) a clear shift to lower phosphoscholine/glycerophosphocholine ratios and sphingomyelin levels. Within each tumour line, metabolic profiles also differed significantly between tumours (i.e., mice). Metastatic tumours exhibited marked inter-tumour changes in polar compounds, some suggesting different glycolytic capacities. Such tumours also showed larger intra-tumour variations in metabolites involved in nucleotide and cholesterol/fatty acid metabolism, in tandem with less changes in TCA and phospholipid metabolism, compared to non-metastatic tumours. This study shows the valuable contribution of untargeted NMR metabolomics to characterise tumour metabolism, thus opening enticing opportunities to find metabolic markers related to metastatic ability in endocrine breast cancer.

One-Minute Synthesis of Size-Controlled Fucoidan-Gold Nanosystems: Antitumoral Activity and Dark Field Imaging

Gold nanoparticles (AuNPs) are one of the most studied nanosystems with great potential for biomedical applications, including cancer therapy. Although some gold-based systems have been described, the use of green and faster methods that allow the control of their properties is of prime importance. Thus, the present study reports a one-minute microwave-assisted synthesis of fucoidan-coated AuNPs with controllable size and high antitumoral activity. The NPs were synthesized using a fucoidan-enriched fraction extracted from Fucus vesiculosus, as the reducing and capping agent. The ensuing monodispersed and spherical NPs exhibit tiny diameters between 5.8 and 13.4 nm for concentrations of fucoidan between 0.5 and 0.05% (w/v), respectively, as excellent colloidal stability in distinct solutions and culture media. Furthermore, the NPs present antitumoral activity against three human tumor cell lines (MNT-1, HepG2, and MG-63), and flow cytometry in combination with dark-field imaging confirmed the cellular uptake of NPs by MG-63 cell line.