Hypertrabeculation; a phenotype with Heterogeneous etiology

Prognostic Value of Multiple Circulating Biomarkers for Ventricular Arrhythmias in Left Ventricular Hypertrabeculation - Longitudinal Cohort Study

BACKGROUND

Ventricular arrhythmia (VA) is an independent risk factor for adverse outcomes in patients with left ventricular hypertrabeculation (LVHT). This study explored the predictive value of biomarkers for VAs in LVHT.

METHODS AND RESULTS

This cohort study retrospectively enrolled 265 LVHT patients (mean [±SD] age 44.2±17.0 years, 65.7% male) with data available for N-terminal pro B-type natriuretic peptide, big endothelin-1, high-sensitivity C-reactive protein, uric acid, and free fatty acid. The primary outcome was a composite of non-sustained ventricular tachycardia, sustained ventricular tachycardia, ventricular fibrillation, and appropriate implantable cardioverter defibrillator therapy. Over a median follow-up of 4.34 years, 82 (30.9%) patients experienced VAs. Multivariable Cox regression analysis revealed that baseline concentrations of big endothelin-1 were independently associated with the occurrence of VAs (hazard ratio 1.513; 95% confidence interval 1.136-2.013; P=0.005). Restricted cubic spline analysis showed that susceptibility to VAs increased markedly with increases in big endothelin-1 concentrations. Subgroup analysis revealed that LVHT patients with big endothelin-1 concentrations >0.63 pmol/L should be closely monitored for VAs, particularly when higher concentrations are accompanied by cardiomyopathies, left ventricular (LV) end-diastolic diameters ≥60 mm, or LV ejection fraction <50%. Individuals with elevated big endothelin-1 concentrations and isolated hypertrabeculation in the LV lateral wall had a significantly greater risk of VAs (log-rank P=0.002).

CONCLUSIONS

Big endothelin-1 concentrations and the location of hypertrabeculation can help with risk stratification for VAs in LVHT.

ABLE-SCORE, a simplified risk score for major adverse cardiovascular outcomes in left ventricular hypertrabeculation: a multicenter longitudinal cohort study

BACKGROUND

Left ventricular hypertrabeculation (LVHT) is a heterogeneous entity with life-threatening complications and variable prognosis. However, there are limited prediction models available to identify individuals at high risk of adverse outcomes, and the current risk score in LVHT is comparatively complex for clinical practice. This study aimed to develop and validate a simplified risk score to predict major adverse cardiovascular events (MACE) in LVHT.

METHODS

This multicenter longitudinal cohort study consecutively enrolled morphologically diagnosed LVHT patients between January 2009 and December 2020 at Fuwai Hospital (derivation cohort, n = 300; internal validation cohort, n = 129), and between January 2014 and December 2022 at two national-level medical centers (external validation cohort, n = 95). The derivation/internal validation cohorts and the external validation cohort were followed annually until December 2022 and December 2023, respectively. MACE was defined as a composite of all-cause mortality, heart transplantation/left ventricular assist device implantation, cardiac resynchronization therapy, malignant ventricular arrhythmia, and thromboembolism. A simplified risk score, the ABLE-SCORE, was developed based on independent risk factors in the multivariable Cox regression predictive model for MACE, and underwent both internal and external validations to confirm its discrimination, calibration, and clinical applicability.

RESULTS

A total of 524 LVHT patients (43.5 ± 16.6 years, 65.8% male) were included in the study. The ABLE-SCORE was established using four easily accessible clinical variables: age at diagnosis, N-terminal pro-brain natriuretic peptide levels, left atrium enlargement, and left ventricular ejection fraction ≤ 40% measured by echocardiography. The risk score showed excellent performance in discrimination, with Harrell's C-index of 0.821 [95% confidence interval (CI), 0.772-0.869], 0.786 (95%CI, 0.703-0.869), and 0.750 (95%CI, 0.644-0.856) in the derivation, internal validation, and external validation cohort, respectively. Calibration plots of the three datasets suggested accurate agreement between the predicted and observed 5-year risk of MACE in LVHT. According to decision curve analysis, the ABLE-SCORE displayed greater net benefits than the existing risk score for LVHT, indicating its strength in clinical applicability.

CONCLUSIONS

A simplified and efficient risk score for MACE was developed and validated using a large LVHT cohort, making it a reliable and convenient tool for the risk stratification and clinical management of patients with LVHT.

Contrast Echocardiography in Heart Failure: Update 2023

PURPOSE OF REVIEW

The application of ultrasound-enhancing agents (contrast agents) has improved the accuracy and reproducibility of echocardiography. The review focuses on the currently approved and evolving indications for contrast echocardiography in patients with heart failure, specifically examining clinical studies conducted after the publication of the guidelines in 2017 and 2018.

RECENT FINDINGS

The current ASE/EACVI recommendations for contrast echocardiography are based on its accuracy and reproducibility in comparison to non-enhanced echocardiography or other imaging modalities like cardiac MRI. However, tissue characterization remains limited with contrast echocardiography. During the last few years, several studies have demonstrated the clinical impact of using contrast agents on the management of patients with heart failure. There is growing evidence on the benefit of using contrast echocardiography in critically ill patients where echocardiography without contrast agents is often suboptimal and other imaging methods are less feasible. There is no risk of worsening renal function after the administration of ultrasound-enhancing agents, and these agents can be administered even in patients with end-stage renal disease. Contrast echocardiography has become a valuable tool for first-line imaging of patients with heart failure across the spectrum of patients with chronic heart failure to critically ill patients.

Highlights of right ventricular characteristics of left ventricular noncompaction using 3D echocardiography

Highlights of right ventricular characteristics of left ventricular noncompaction using 3D echocardiography. The aspects of right ventricular volumes and function investigated with 3D echocardiography in a large cohort of left ventricular noncompaction morphology (LVNC) population remains unclear. The objective of our research was to study the left (LV) and right (RV) ventricular parameters using 3D echocardiography and analyze the clinical features of a LVNC population with preserved LV ejection fraction (EF > 50 %) in comparison with healthy controls (HC). We selected 41 LVNC subjects with preserved LV function (EF: 52.91 ± 3 %, male n = 26) and without any comorbidities and compared them with an age and sex-matched HC. Three dimensional endocardial contours were evaluated to determine the following LV and RV parameters: end-diastolic (EDV) and end-systolic (ESV) volumes, stroke volume, EF, LV global longitudinal and circumferential strain and RV septal and free wall longitudinal strain. Regarding the clinical characteristics, the family involvement had a notable proportion, accounting for 51%. The EF and strain values of the LVNC population were significantly decreased in both RV and LV compared to HC. Although the LV volumes of the LVNC group were significantly elevated, the RV volumetric parameters did not differ significantly compared to controls. We found significant correlations between LV and RV volumetric and functional parameters and linear regression models showed that LV EDV and LV ESV determined the RV volumetric values. While the alteration and relationship of the RV parameters may represent the potential of biventricular involvement, clinical characteristics of the LVNC group underlines the necessity of monitoring this population, even with preserved EF.

Established and emerging roles for ultrasound enhancing agents (contrast echocardiography)

The ability to opacify the left ventricle and delineate the endocardium after intravenous injection of microbubble ultrasound enhancing agents is of established value to quantify volumes and function in suboptimal unenhanced images, particularly in stress echocardiograms. However, applications other than quantitation of left ventricle structure and function exist for contrast enhanced left ventricular opacification. Contrast agents enable recording of Doppler velocity signals in patients with poor ultrasound transmission, providing estimates of aortic stenosis gradient and pulmonary artery pressures. Contrast echo is of value in detecting apical hypertrophic cardiomyopathy and accompanying apical aneurysms. Most importantly, ultrasound enhancing agents can identify apical and left atrial masses when they cannot be visualized in unenhanced images, and can distinguish thrombi from tumors by visualizing the vascularity inherent in tumors. Contrast agents distinguish trabecular from compacted myocardium in noncompaction syndrome, and hypertrabeculation with other abnormal conditions. A major potential application of ultrasound enhancing agents is myocardial opacification, which can assist in identifying nonviable myocardium. Also, the delayed reappearance of myocardial perfusion after microbubble destruction identifies impaired contrary flow and can diagnose coronary stenosis. Innovative applications of ultrasound contrast agents currently under investigation, include visualizing the vaso vasorum to identify plaques and assess their vulnerability, and theranostic agents to deliver drugs and biologists and to assist in sonothrombolysis. It is anticipated that the role of ultrasound contrast agents will continue to increase in the future.

Left Ventricular Non-Compaction Cardiomyopathy-Still More Questions than Answers

Left ventricular non-compaction (LVNC) describes the phenotypical phenomena characterized by the presence of excessive trabeculation of the left ventricle which forms a deep recess filled with blood. Considering the lack of a uniform definition of LVNC as well as the "golden standard" it is difficult to estimate the actual incidence of the disease, however, seems to be overdiagnosed, due to unspecific diagnostic criteria. The non-compacted myocardium may appear both as a disease representation or variant of the norm or as an adaptive phenomenon. This article covers different approaches to incidence, pathogenesis, diagnostics, and treatment of LVNC as well as recommendations for patients during follow-up.