Apical Transverse Motion Is Associated with Interventricular Mechanical Delay and Decreased Left Ventricular Function in Children with Dilated Cardiomyopathy

Congenital anomalous drainage of the inferior vena cava and hepatic veins into the left atrium associated with long QT syndrome: Multimodality imaging, pitfalls, and caveats

Isolated congenital anomalous drainage of the inferior vena cava (IVC) and partial hepatic veins (HV) into the left atrium (LA) via an interatrial communication (IAC), associated with the normal connection of the IVC to the right atrium is exceedingly rare. Therefore, there is a dearth of knowledge regarding the management of these cases. To date, there has been no report of abnormal IVC drainage caused by abnormal IVC-IAC alignment. Much more frequently, patients have an abnormal connection or abnormal drainage mediated by a persistent Eustachian valve that allows blood to pass from the inferior vena cava to the left atrium. Herein, we report an 8-year-old boy with anomalous IVC and hepatic vein drainage into the LA due to IVC-IAC malalignment. We describe the findings of multimodality imaging, including transthoracic, transesophageal, contrast, and speckle-tracking echocardiography, cardiac angiography, and cardiac magnetic resonance imaging. We go over the diagnostic and therapeutic pitfalls and caveats of this case that can apply to similar patients.

The Prognostic Value of Left Ventricular Mechanical Dyssynchrony Derived from Cardiac MRI in Patients with Idiopathic Dilated Cardiomyopathy

Purpose

To investigate the prognostic value of mechanical dyssynchrony evaluated by deformable registration algorithm (DRA) analysis of cardiac MRI (CMR) in patients with idiopathic dilated cardiomyopathy (DCM).

Materials and Methods

This secondary analysis of a prospective study (clinical trial no. ChiCTR1800017058) enrolled 409 patients (mean age, 48 years ± 14:300 men) with idiopathic DCM who underwent CMR between June 2012 and September 2018. Mechanical dyssynchrony was measured as standard deviation of time-to-peak (sdTTP) and uniformity ratio estimate (URE) indexes by DRA strain analysis. The primary endpoint included all-cause mortality and heart transplantation. The secondary endpoint included primary endpoint, aborted sudden cardiac death, and heart failure readmission. Cox regression analyses and Kaplan-Meier survival analysis were performed to identify the association between variables and outcomes.

Results

During a median follow-up of 25.1 months, 57 and 132 patients reached primary and secondary endpoints, respectively. Most URE indexes were significantly lower in patients reaching primary endpoint. In multivariable analysis, circumferential URE (CURE) at apical level was independently associated with primary endpoints (hazard ratio, 0.307 [95% CI: 0.106, 0.883]; P = .03) and secondary endpoints (hazard ratio, 0.452 [95% CI: 0.209, 0.979]; P = .04), whereas most sdTTP measures were not. Furthermore, among patients with left ventricular ejection fraction of less than 35% or presence of late gadolinium enhancement, those with CURE at apical level of less than 0.917 had a significantly higher rate of adverse outcomes.

Conclusion

URE indexes were more predictive of prognostic outcomes compared with sdTTP measurements; the CURE at apical level was an independent predictor of adverse cardiac events in patients with DCM.Keywords: Heart, Outcomes Analysis, MR-ImagingClinical trial registration no. ChiCTR1800017058 Supplemental material is available for this article. See also commentary by Rajiah and François in this issue.© RSNA, 2021.

Network-based computational approach to identify genetic links between cardiomyopathy and its risk factors

Cardiomyopathy (CMP) is a group of myocardial diseases that progressively impair cardiac function. The mechanisms underlying CMP development are poorly understood, but lifestyle factors are clearly implicated as risk factors. This study aimed to identify molecular biomarkers involved in inflammatory CMP development and progression using a systems biology approach. The authors analysed microarray gene expression datasets from CMP and tissues affected by risk factors including smoking, ageing factors, high body fat, clinical depression status, insulin resistance, high dietary red meat intake, chronic alcohol consumption, obesity, high-calorie diet and high-fat diet. The authors identified differentially expressed genes (DEGs) from each dataset and compared those from CMP and risk factor datasets to identify common DEGs. Gene set enrichment analyses identified metabolic and signalling pathways, including MAPK, RAS signalling and cardiomyopathy pathways. Protein-protein interaction (PPI) network analysis identified protein subnetworks and ten hub proteins (CDK2, ATM, CDT1, NCOR2, HIST1H4A, HIST1H4B, HIST1H4C, HIST1H4D, HIST1H4E and HIST1H4L). Five transcription factors (FOXC1, GATA2, FOXL1, YY1, CREB1) and five miRNAs were also identified in CMP. Thus the authors' approach reveals candidate biomarkers that may enhance understanding of mechanisms underlying CMP and their link to risk factors. Such biomarkers may also be useful to develop new therapeutics for CMP.

Quantitative mechanical dyssynchrony in dilated cardiomyopathy measured by deformable registration algorithm

OBJECTIVES

To investigate the diagnostic value and reproducibility of deformable registration algorithm (DRA)-derived mechanical dyssynchrony parameters in dilated cardiomyopathy (DCM) patients.

METHODS

The present study included 80 DCM patients (40 with normal QRS duration (NQRS-DCM); 40 with left bundle branch block (LBBB-DCM)) and 20 healthy volunteers. The balanced steady-state free-precession (bSSFP) cine images were acquired using a 3.0T scanner. Mechanical dyssynchrony parameters were calculated based on DRA-derived segmental strain, including uniformity ratio estimate (URE) and standard derivation of time-to-peak (T2Psd) parameters in circumferential, radial, and longitudinal orientations.

RESULTS

DCM patients showed significant mechanical dyssynchrony reflected by both URE and T2Psd parameters compared with controls. Among DCM patients, LBBB-DCM showed decreased CURE (0.78 ± 0.21 vs. 0.93 ± 0.05, p < 0.001) and RURE (0.69 ± 0.14 vs. 0.83 ± 0.15, p = 0.001), and increased T2Psd-Ecc (median with interquartile range, 94.1 (54.4-123.2) ms vs. 63.7 (44.9-80.4) ms, p = 0.003) and T2Psd-Err (91.1 (61.1-103.2) ms vs. 62.3 (46.3-104.5) ms, p = 0.041) compared with NQRS-DCM patients. CURE showed a strong correlation with QRS duration (r = - 0.54, p < 0.001), with maximum AUC (0.791) to differentiate LBBB-DCM from NQRS-DCM patients. Improved intra- and inter-observer reproducibility was found using URE indices (coefficient of variation (CoV), 1.20-3.17%) than T2Psd parameters (CoV, 15.28-41.18%).

CONCLUSIONS

The DRA-based CURE showed significant correlation with QRS duration and the highest discriminatory value between LBBB-DCM and NQRS-DCM patients. URE indices showed greater reproducibility compared with T2Psd parameters for assessing myocardial dyssynchrony in DCM patients.

KEY POINTS

• The strain analyses based on DRA suggested that DCM patients have varying degrees of mechanical dyssynchrony and there is a significant difference from normal controls. • CURE showed the strongest correlation with QRS duration and was the best parameter for differentiating DCM patients with normal QRS duration from patients with LBBB, and with normal controls. • URE indices showed improved reproducibility compared with T2Psd parameters in all three orientations (circumferential, radial, and longitudinal).