Constrictive pericarditis and restrictive cardiomyopathy in the modern era

Multimodality Imaging in Differentiating Constrictive Pericarditis From Restrictive Cardiomyopathy: A Comprehensive Overview for Clinicians and Imagers

In the evaluation of heart failure, 2 differential diagnostic considerations include constrictive pericarditis and restrictive cardiomyopathy. The often outwardly similar clinical presentation of these 2 pathologic entities routinely renders their clinical distinction difficult. Consequently, initial assessment requires a keen understanding of their separate pathophysiology, epidemiology, and hemodynamic effects. Following a detailed clinical evaluation, further assessment initially rests on comprehensive echocardiographic investigation, including detailed Doppler evaluation. With the combination of mitral inflow characterization, tissue Doppler assessment, and hepatic vein interrogation, initial differentiation of constrictive pericarditis and restrictive cardiomyopathy is often possible with high sensitivity and specificity. In conjunction with a compatible clinical presentation, successful differentiation enables both an accurate diagnosis and subsequent targeted management. In certain cases, however, the diagnosis remains unclear despite echocardiographic assessment, and additional evaluation is required. With advances in noninvasive tools, such evaluation can often continue in a stepwise, algorithmic fashion noninvasively, including both cross-sectional and nuclear imaging. Should this additional evaluation itself prove insufficient, invasive assessment with appropriate expertise may ultimately be necessary.

Prevalence and Impact of Arrhythmia on Outcomes in Restrictive Cardiomyopathy-A Report from the Beijing Municipal Health Commission Information Center (BMHCIC) Database

BACKGROUND

Data on the outcomes of restrictive cardiomyopathy (RCM) are limited, when the condition is complicated with arrhythmia. This study was designed to investigate the prevalence of atrial fibrillation (AF), ventricular tachycardia (VT) and bradycardia (BC) and their impact on adverse outcomes (intra-cardiac thrombus, stroke and systematic embolism [SSE], heart failure and death) of RCM.

METHODS AND RESULTS

The retrospective cohort study used data collected from the Beijing Municipal Health Commission Information Center (BMHCIC) database from 1 January 2010 to 31 December 2020. There were 745 (64.9%) patients with AF, 117 (10.2%) patients with VT and 311 (27.1%) patients with bradycardia. The presence of AF was associated with an increased risk of SSE (adjusted HR:1.37, 95%CI:1.02-1.83, p = 0.04) and heart failure (aHR:1.36, 95%CI:1.17-1.58, p < 0.001). VT was associated with an increased risk of intracardiac thrombus (aHR:2.34, 95%CI:1.36-4.01, p = 0.002) and death (aHR:2.07, 95%CI:1.19-3.59, p = 0.01). Bradycardia did not increase the adverse outcomes in RCM. The results remained consistent and steady when AF, VT and bradycardia were adjusted as competing factors.

CONCLUSIONS

Cardiac arrhythmia are highly prevalent and associated with adverse outcomes in patients with RCM. AF and VT are more likely to be associated with intracardiac thrombosis, and the presence of AF increased the risk of SSE and HF. The presence of VT increased the risk of death.

Experimental Research on the Evaluation of Left Ventricular Function by Layered Speckle Tracking in a Constrictive Pericarditis Rat Model

OBJECTIVES

In animal models with constrictive pericarditis (CP), detecting the function of cardiac systole by conventional noninvasive ultrasound is a challenge. We aimed to detect cardiac dysfunction in rat models with CP in the early stage by layered speckle tracking.

METHODS

We compared a rat CP model (n = 23, injected with a solution of 1-mg/mL lipopolysaccharides [0.5 mL] and a 10% talc suspension [0.5 mL]) with a control group (n = 20, no injection). After 8 weeks, conventional echocardiography and layered speckle tracking were used to assess the left ventricular structures and functions in the groups.

RESULTS

The global circumferential strain (CS) and longitudinal strain (LS) were decreased in the CP group (P < .05). The CS of the epicardial and middle layers in the CP group was decreased (P < .05), but the endocardial layer was not statistically different. The LS of the epicardial layer was decreased (P < .05), but the middle and endocardial layers were not statistically different. The global free-wall and septal-wall CS of the CP group was decreased (P < .05), mainly due to the decrease of CS of the epicardial and middle layers. The global free-wall LS of the CP group was decreased (P < .05), mainly due to the decrease of LS of the epicardial and middle layers. There were no significant differences between the groups in global LS of the septal wall.

CONCLUSIONS

In the early stage of CP, subepicardial myocardial damage precedes that of the subendocardial myocardium, and free-wall damage precedes that of the septal wall.

Tuberculous Constrictive Pericarditis

INTRODUCTION

Constrictive pericarditis is characterized by constriction of the heart secondary to pericardial inflammation. Cardiovascular magnetic resonance (CMR) imaging is useful imaging modality for addressing the challenges of confirming this diagnosis. It can be used to exclude other causes of right heart failure, such as pulmonary hypertension or myocardial infarction, determine whether the pericardium is causing constriction and differentiate it from restrictive cardiomyopathy, which also causes impaired cardiac filling.

CASE PRESENTATION

A 77-year-old man from a country with high incidence of tuberculosis presented with severe dyspnea. Echocardiography revealed a small left ventricle with normal systolic and mildly impaired diastolic function. Left heart catheterization revealed non-obstructive coronary disease, not felt contributory to the dyspnea. Anatomy imaging with cardiovascular magnetic resonance imaging (CMR) showed global, severely thickened pericardium. Short tau inversion recovery (STIR) sequences for detection of oedema/ inflammation showed increased signal intensity and free breathing sequences confirmed septal flattening on inspiration. Late gadolinium imaging confirmed enhancement in the pericardium, with all findings suggestive of pericardial inflammation and constriction.

CONCLUSIONS

CMR with STIR sequences, free breathing sequences and late gadolinium imaging can prove extremely useful for diagnosing constrictive pericarditis.

Use of Cardiac Magnetic Resonance Imaging Based Measurements of Inferior Vena Cava Cross-Sectional Area in the Diagnosis of Pericardial Constriction

Purpose

To evaluate the value of cardiac magnetic resonance imaging (MRI)–based measurements of inferior vena cava (IVC) cross-sectional area in the diagnosis of pericardial constriction.

Methods

Patients who had undergone cardiac MRI for evaluation of clinically suspected pericardial constriction were identified retrospectively. The diagnosis of pericardial constriction was established by clinical history, echocardiography, cardiac catheterization, intraoperative findings, and/or histopathology. Cross-sectional areas of the suprahepatic IVC and descending aorta were measured on a single axial steady-state free-precession (SSFP) image at the level of the esophageal hiatus in end-systole. Logistic regression and receiver-operating curve (ROC) analyses were performed.

Results

Thirty-six patients were included; 50% (n = 18) had pericardial constriction. Mean age was 53.9 ± 15.3 years, and 72% (n = 26) were male. IVC area, ratio of IVC to aortic area, pericardial thickness, and presence of respirophasic septal shift were all significantly different between patients with constriction and those without ( P < .001 for all). IVC to aortic area ratio had the highest odds ratio for the prediction of constriction (1070, 95% confidence interval [8.0-143051], P = .005). ROC analysis illustrated that IVC to aortic area ratio discriminated between those with and without constriction with an area under the curve of 0.96 (95% confidence interval [0.91-1.00]).

Conclusions

In patients referred for cardiac MRI assessment of suspected pericardial constriction, measurement of suprahepatic IVC cross-sectional area may be useful in confirming the diagnosis of constriction when used in combination with other imaging findings, including pericardial thickness and respirophasic septal shift.

Constrictive pericarditis post-lung transplant

Constrictive pericarditis is a rare entity following lung transplant, with only seven previous cases reported in the literature. We present two additional cases and review the literature on this subject. Constrictive pericarditis should be considered in lung transplant patients who present with dyspnea and evidence of cardiac failure. Pericardiectomy remains the treatment of choice irrespective of the etiology.

Role of Interleukin-1 in Radiation-Induced Cardiomyopathy

Thoracic X-ray therapy (XRT), used in cancer treatment, is associated with increased risk of heart failure. XRT-mediated injury to the heart induces an inflammatory response leading to cardiomyopathy. The aim of this study was to determine the role of interleukin (IL)-1 in response to XRT injury to the heart and on the cardiomyopathy development in the mouse. Female mice with genetic deletion of the IL-1 receptor type I (IL-1R1 knockout mice [IL-1R1 KO]) and treatment with recombinant human IL-1 receptor antagonist anakinra, 10 mg/kg twice daily for 7 d, were used as independent approaches to determine the role of IL-1. Wild-type (wt) or IL-1R1 KO mice were treated with a single session of XRT (20 or 14 gray [Gy]). Echocardiography (before and after isoproterenol challenge) and left ventricular (LV) catheterization were performed to evaluate changes in LV dimensions and function. Masson's trichrome was used to assess myocardial fibrosis and pericardial thickening. After 20 Gy, the contractile reserve was impaired in wt mice at d 3, and the LV ejection fraction (EF) was reduced after 4 months when compared with sham-XRT. IL-1R1 KO mice had preserved contractile reserve at 3 d and 4 months and LVEF at 4 months after XRT. Anakinra treatment for 1 d before and 7 d after XRT prevented the impairment in contractile reserve. A significant increase in LV end-diastolic pressure, associated with increased myocardial interstitial fibrosis and pericardial thickening, was observed in wt mice, as well as in IL-1R1 KO-or anakinra-treated mice. In conclusion, induction of IL-1 by XRT mediates the development of some, such as the contractile impairment, but not all aspects of the XRT-induced cardiomyopathy, such as myocardial fibrosis or pericardial thickening.