Left ventricular strain-curve morphology to distinguish between constrictive pericarditis and restrictive cardiomyopathy

Epicardial adipose tissue and pericardial constraint in heart failure with preserved ejection fraction

AIMS

Obesity and epicardial adiposity play a role in the pathophysiology of heart failure with preserved ejection fraction (HFpEF), and both are associated with increased filling pressures and reduced exercise capacity. The haemodynamic basis for these observations remains inaccurately defined. We hypothesize that an abundance of epicardial adipose tissue (EAT) within the pericardial sac is associated with haemodynamic signs of pericardial constraint.

METHODS AND RESULTS

HFpEF patients who underwent invasive heart catheterization with simultaneous echocardiography were included. Right atrial pressure (RAP), right ventricular end-diastolic pressure, and pulmonary capillary wedge pressure (PCWP) were invasively measured. The presence of a square root sign on the right ventricular pressure waveform and the RAP/PCWP ratio (surrogate parameters for pericardial constraint) were investigated. EAT thickness alongside the right ventricle was measured on echocardiography. Sixty-four patients were studied, with a mean age of 73 ± 10 years, 64% women, and a mean body mass index (BMI) of 28.6 ± 5.4 kg/m2. In total, 47 patients (73%) had a square root sign. The presence of a square root sign was associated with higher BMI (29.3 vs. 26.7 kg/m2, P = 0.02), higher EAT (4.0 vs. 3.4 mm, P = 0.03), and higher RAP (9 vs. 6 mmHg, P = 0.04). Women had more EAT than men (4.1 vs. 3.5 mm, P = 0.04), despite a comparable BMI. Women with a square root sign had significantly higher EAT (4.3 vs. 3.3 mm, P = 0.02), a higher mean RAP (9 vs. 5 mmHg, P = 0.02), and a higher RAP/PCWP ratio (0.52 vs. 0.26, P = 0.002). In men, such associations were not seen, although there was no significant interaction between men and women (P > 0.05 for all analyses).

CONCLUSIONS

Obesity and epicardial adiposity are associated with haemodynamic signs of pericardial constraint in patients with HFpEF. The pathophysiological and therapeutic implications of this finding need further study.

A novel multi-task machine learning classifier for rare disease patterning using cardiac strain imaging data

To provide accurate predictions, current machine learning-based solutions require large, manually labeled training datasets. We implement persistent homology (PH), a topological tool for studying the pattern of data, to analyze echocardiography-based strain data and differentiate between rare diseases like constrictive pericarditis (CP) and restrictive cardiomyopathy (RCM). Patient population (retrospectively registered) included those presenting with heart failure due to CP (n = 51), RCM (n = 47), and patients without heart failure symptoms (n = 53). Longitudinal, radial, and circumferential strains/strain rates for left ventricular segments were processed into topological feature vectors using Machine learning PH workflow. In differentiating CP and RCM, the PH workflow model had a ROC AUC of 0.94 (Sensitivity = 92%, Specificity = 81%), compared with the GLS model AUC of 0.69 (Sensitivity = 65%, Specificity = 66%). In differentiating between all three conditions, the PH workflow model had an AUC of 0.83 (Sensitivity = 68%, Specificity = 84%), compared with the GLS model AUC of 0.68 (Sensitivity = 52% and Specificity = 76%). By employing persistent homology to differentiate the "pattern" of cardiac deformations, our machine-learning approach provides reasonable accuracy when evaluating small datasets and aids in understanding and visualizing patterns of cardiac imaging data in clinically challenging disease states.

Cardiac magnetic resonance feature tracking derived left atrial strain in the diagnosis of patients with constrictive pericarditis and restrictive cardiomyopathy

Objective

To explore the diagnostic value of cardiac magnetic resonance feature tracking (CMR-FT) divided left atrial (LA) strain in differentiating constrictive pericarditis (CP) and restrictive cardiomyopathy (RCM).

Methods

Patients with CP (n = 40) and RCM (n = 40), and another 40 normal control group were retrospectively enrolled over a period of 8 years at a tertiary cardiac centre. Left ventricular (LV) and biatrial strain and strain rate (SR) were measured. Atrial strain was used to differentiate between patients with CP and RCM. Then, patients were grouped according to their left ventricular ejection fraction (LVEF), either ≥50% or < 50%. A deeper analysis was done to evaluate the diagnostic value of atrial strain in these subgroups. Receiver operating characteristic curves (ROC) were used to assess the accuracy of myocardial strain based on CMR FT for the differential diagnosis of CP and RCM.

Results

LV and LA strain and SR were significantly lower in patients with CP and RCM than those in the normal controls (P < 0.05). LA strain and SR were significantly lower in the RCM group than in the CP group (P < 0.05). In patients with either LVEF≥50% or＜50%, LA strain were lower in the RCM group than in the CP group (P < 0.05). ROC analysis showed that LA stored strain (LA-εs) had a good differential diagnostic value for CP and RCM, with an area under the curve (AUC) of 0.811 and an optimal cutoff value of 6.98%, above this value it tends to develop CP. Further, an excellent differential diagnostic value was found in patients with LVEF＜50%, with an AUC of 0.955.

Conclusion

LA strain analysis obtained by CMR-FT provides good differential diagnostic value for distinguishing CP from RCM, especially in patients with LVEF＜50%.

Cardiac magnetic resonance imaging of pericardial diseases: a comprehensive guide

Cardiac magnetic resonance (CMR) imaging has been established as a valuable diagnostic tool in the assessment of pericardial diseases by providing information on cardiac anatomy and function, surrounding extra-cardiac structures, pericardial thickening and effusion, characterization of pericardial effusion, and the presence of active pericardial inflammation from the same scan. In addition, CMR imaging has excellent diagnostic accuracy for the non-invasive detection of constrictive physiology evading the need for invasive catheterization in most instances. Growing evidence in the field suggests that pericardial enhancement on CMR is not only diagnostic of pericarditis but also has prognostic value for pericarditis recurrence, although such evidence is derived from small patient cohorts. CMR findings could also be used to guide treatment de-escalation or up-titration in recurrent pericarditis and selecting patients most likely to benefit from novel treatments such as anakinra and rilonacept. This article is an overview of the CMR applications in pericardial syndromes as a primer for reporting physicians. We sought to provide a summary of the clinical protocols used and an interpretation of the major CMR findings in the setting of pericardial diseases. We also discuss points that are less well clear and delineate the strengths and weak points of CMR in pericardial diseases.

Updates on the Global Prevalence and Etiology of Constrictive Pericarditis: A Systematic Review

Constrictive pericarditis is a rare disease with poorly understood epidemiology. A systematic literature search was adopted to assess the region- and period-specific traits of constrictive pericarditis through Pubmed, EMBASE, and Scopus. Case reports and studies including less than 20 patients were excluded. The risk of bias was assessed through the Study Quality Assessment Tools developed by the National Heart Lung Blood Institute by 4 reviewers. Patient demographics, disease etiology, and mortality were the primary assessed outcomes. One hundred thirty studies with 11,325 patients have been included in this systematic review and meta-analysis. The age at diagnosis of constrictive pericarditis has markedly increased after 1990. Patients from Africa and Asia are considerably younger compared with those from Europe and North America. Moreover, there are differences in etiology, as tuberculosis remains the dominant cause of constrictive pericarditis in Africa and Asia but has been surpassed by history of previous chest surgery in North America and Europe. The human immunodeficiency virus affects 29.1% of patients from Africa diagnosed with constrictive pericarditis, a feature that is not observed on any other continent. The early mortality rate after hospitalization has improved. The variances of age at diagnosis and etiology of constrictive pericarditis should be considered by the clinician during the work-up of cardiac and pericardial diseases. An underlying human immunodeficiency virus infection complicates a significant portion of constrictive pericarditis cases in Africa. Early mortality has improved across the world but remains high.

Age- and sex-specific reference values of biventricular strain and strain rate derived from a large cohort of healthy Chinese adults: a cardiovascular magnetic resonance feature tracking study

BACKGROUND

As a noninvasive tool, myocardial deformation imaging may facilitate the early detection of cardiac dysfunction. However, normal reference ranges of myocardial strain and strain rate (SR) based on large-scale East Asian populations are still lacking. This study aimed to provide reference values of left ventricular (LV) and right ventricular (RV) strain and SR based on a large cohort of healthy Chinese adults using cardiovascular magnetic resonance (CMR) feature tracking (FT).

METHODS

Five hundred and sixty-six healthy Chinese adults (55.1% men) free of hypertension, diabetes, and obesity were included. On cine CMR, biventricular global radial, circumferential, and longitudinal strain (GRS, GCS, and GLS), and the peak radial, circumferential, and longitudinal systolic, and diastolic SRs (PSSRR, PSSRC, PSSRL, PDSRR, PDSRC, and PDSRL), and regional radial and circumferential strain at the basal, mid-cavity, and apical levels were measured. Associations of global and regional biventricular deformation indices with age and sex were investigated.

RESULTS

Women demonstrated greater magnitudes of LV GRS (37.6 ± 6.1% vs. 32.1 ± 5.3%), GCS (- 20.7 ± 1.9% vs. - 18.8 ± 1.9%), GLS (- 17.8 ± 1.8% vs. - 15.6 ± 1.8%), RV GRS (25.1 ± 7.8% vs. 22.1 ± 6.7%), GCS (- 14.4 ± 3.6% vs. - 13.2 ± 3.2%), GLS (- 22.4 ± 5.2% vs. - 20.2 ± 4.6%), and biventricular peak systolic and diastolic SR in all three coordinate directions (all P < 0.05). For the LV, aging was associated with increasing amplitudes of GRS, GCS, and decreasing amplitudes of PDSRR, PDSRC, PDSRL (all P < 0.05). For the RV, aging was associated with an increase in the magnitudes of GRS, GCS, GLS, PSSRR, PSSRC, PSSRL, and a decrease in the magnitude of PDSRR, PDSRC (all P < 0.05). Biventricular radial and circumferential strain measurements at the basal, mid-cavity, and apical levels were all significantly related to age and sex in both sexes (all P < 0.05).

CONCLUSIONS

We provide age- and sex-specific normal values of biventricular strain and SR based on a large sample of healthy Chinese adults with a broad age range. These results may be served as a reference standard for cardiac function assessment, especially for the Chinese population.

Multimodality Imaging of Constrictive Pericarditis: Pathophysiology and New Concepts

Purpose of Review

The unique pathophysiological changes of constrictive pericarditis (CP) can now be identified with better imaging modalities, thereby helping in its early diagnosis. Through this review, we outline the pathophysiology of CP and its translation into symptomology and various imaging findings which then are used for both diagnosis and guiding treatment options for CP.

Recent Findings

Multimodality imaging has provided us with the capability to recognize early stages of the disease and identify patients with a potential for reversibility and can be treated with medical management. Additionally, peri-procedural planning and prediction of post-operative complications has been made possible with the use of advanced imaging techniques.

Summary

Advanced imaging has the potential to play a greater role in identification of patients with reversible disease process and provide peri-procedural risk stratification, thereby improving outcomes for patients with CP.

Cardiac Magnetic Resonance Imaging Techniques and Applications for Pericardial Diseases

Cardiac magnetic resonance imaging plays a central role among multimodality imaging modalities in the assessment, diagnosis, and surveillance of pericardial diseases. Clinicians and imagers should have a foundational understanding of the utilities, advantages, and limitations of cardiac magnetic resonance imaging and how they integrate with other diagnostic tools involved in the evaluation and management of pericardial diseases. This review aims to outline the contemporary magnetic resonance imaging sequences used to evaluate the pericardium, followed by exploring the main clinical applications of magnetic resonance imaging for identifying pericardial inflammation, constriction, and effusion.

Case Report: “Gourd-Shaped” Heart Strangled by Localized Annular Calcification of the Left Ventricle: A Rare Case of Constrictive Pericarditis

We report a rare case of a 43-year-old woman with calcific annular constrictive pericarditis (CP) encircling the basal segment of the right ventricle and the mid-segment of the left ventricle (LV) lateral wall. Over time, localized calcification has caused LV to be tightly strangled and shaped like a gourd. However, multimodality imaging confirmed no significantly clinical constriction associated with decreased cardiac movement and function. Additionally, cardiac magnetic resonance feature tracking confirmed the relatively preserved diastolic function and the characteristic “plateau” pattern of CP. The treatment strategy of this case is challenging and dialectical.