Myocardial oedema: pathophysiological basis and implications for the failing heart

Acute Kidney Injury and Subsequent Cardiovascular Disease: Epidemiology, Pathophysiology, and Treatment

Cardiovascular disease poses a significant threat to individuals with kidney disease, including those affected by acute kidney injury (AKI). In the short term, AKI has several physiological consequences that can impact the cardiovascular system. These include fluid and sodium overload, activation of the renin-angiotensin-aldosterone system and sympathetic nervous system, and inflammation along with metabolic complications of AKI (acidosis, electrolyte imbalance, buildup of uremic toxins). Recent studies highlight the role of AKI in elevating long-term risks of hypertension, thromboembolism, stroke, and major adverse cardiovascular events, though some of this increased risk may be due to the impact of AKI on the course of chronic kidney disease. Current management strategies involve avoiding nephrotoxic agents, optimizing hemodynamics and fluid balance, and considering renin-angiotensin-aldosterone system inhibition or sodium-glucose cotransporter 2 inhibitors. However, future research is imperative to advance preventive and therapeutic strategies for cardiovascular complications in AKI. This review explores the existing knowledge on the cardiovascular consequences of AKI, delving into epidemiology, pathophysiology, and treatment of various cardiovascular complications following AKI.

Reperfusion Injury in Patients With Acute Myocardial Infarction: JACC Scientific Statement

Despite impressive improvements in the care of patients with ST-segment elevation myocardial infarction, mortality remains high. Reperfusion is necessary for myocardial salvage, but the abrupt return of flow sets off a cascade of injurious processes that can lead to further necrosis. This has been termed myocardial ischemia-reperfusion injury and is the subject of this review. The pathologic and molecular bases for myocardial ischemia-reperfusion injury are increasingly understood and include injury from reactive oxygen species, inflammation, calcium overload, endothelial dysfunction, and impaired microvascular flow. A variety of pharmacologic strategies have been developed that have worked well in preclinical models and some have shown promise in the clinical setting. In addition, there are newer mechanical approaches including mechanical unloading of the heart prior to reperfusion that are in current clinical trials.

Acute Response of the Noninfarcted Myocardium and Surrounding Tissue Assessed by T2 Mapping After STEMI

BACKGROUND

ST-segment elevation myocardial infarction (STEMI) is associated with a systemic and local inflammatory response with edema. However, their role at the tissue level is poorly characterized.

OBJECTIVES

This study aims to characterize T2 values of the noninfarcted myocardium (NIM) and surrounding tissue and to investigate prognostic relevance of higher NIM T2 values after STEMI.

METHODS

A total of 171 consecutive patients with STEMI without prior cardiovascular events who underwent cardiac magnetic resonance after primary percutaneous coronary intervention were analyzed in terms of standard infarct characteristics. Edema of the NIM, liver, spleen, and pectoralis muscle was assessed based on T2 mapping. Follow-up was available for 130 patients. The primary endpoint was major adverse cardiac events (MACE), defined as cardiovascular death, myocardial infarction, unplanned coronary revascularization or rehospitalization for heart failure. The median time from primary percutaneous coronary intervention to cardiac magnetic resonance was 3 days (IQR: 2-5 days).

RESULTS

Higher (above the median value of 45 ms) T2 values in the NIM area were associated with larger infarct size, microvascular obstruction, and left ventricular dysfunction and did not correlate with C-reactive protein, white blood cells, or T2 values of the pectoralis muscle, liver, and spleen. At a median follow-up of 17 months, patients with higher (>45 ms) NIM T2 values had increased risk of MACE (P < 0.001) compared with subjects with NIM T2 values ≤45 ms, mainly caused by a higher rate of myocardial reinfarction (26.3% vs 1.4%; P < 0.001). At multivariable analysis, higher NIM T2 values independently predicted MACE (HR: 2.824 [95% CI: 1.254-6.361]; P = 0.012).

CONCLUSIONS

Higher NIM T2 values after STEMI are independently associated with worse cardiovascular outcomes, mainly because of higher risk of myocardial infarction.

Myocardial edema, inflammation, and injury in human heart donated after circulatory death are sensitive to warm ischemia and subsequent cold storage

BACKGROUND

Single-dose del Nido solution was recently used in human donation after circulatory death (DCD) heart procurement. We compared the effect of del Nido cardioplegia on myocardial edema, inflammatory response, and injury in human DCD hearts and human donation after brain death (DBD) hearts with different warm ischemic times (WIT) and subsequent cold saline storage times (CST).

METHODS

A total of 24 human hearts, including 6 in the DBD group and 18 in the DCD group-were procured for the research study. The DCD group was divided into 3 subgroups based on WIT: 20, 40, and ≥60 minutes. All hearts received 1 L of del Nido cardioplegia before being placed in cold saline for 6 hours. Left ventricular biopsies were performed at 0, 2, 4, and 6 hours. Temporal changes in myocardial edema, inflammatory cytokines (TNF-α, IL-6, and IL-1β), and histopathology injury scores were compared between the DBD and DCD groups.

RESULTS

DCD hearts showed more profound changes in myocardial edema, inflammation, and injury than DBD hearts at baseline and subsequent CST. The DCD heart with WIT of 20 and 40 minutes with CST of 4 and 2 hours, respectively, appeared to have limited myocardial edema, inflammation, and injury. DCD hearts with WIT ≥60 minutes showed severe myocardial edema, inflammation, and injury at baseline and subsequent CST.

CONCLUSIONS

Single-dose cold del Nido cardioplegia and subsequent cold normal saline storage can preserve both DCD and DBD hearts. DCD hearts have been shown to be able to tolerate a WIT of 20 minutes and subsequent CST of 4 hours without experiencing significant myocardial edema, inflammation, and injury.

Mechanisms of Myocardial Edema Development in CVD Pathophysiology

Myocardial edema is the excess accumulation of fluid in the myocardial interstitium or cardiac cells that develops due to changes in capillary permeability, loss of glycocalyx charge, imbalance in lymphatic drainage, or a combination of these factors. Today it is believed that this condition is not only a complication of cardiovascular diseases, but in itself causes aggravation of the disease and increases the risks of adverse outcomes. The study of molecular, genetic, and mechanical changes in the myocardium during edema may contribute to the development of new approaches to the diagnosis and treatment of this condition. This review was conducted to describe the main mechanisms of myocardial edema development at the molecular and cellular levels and to identify promising targets for the regulation of this condition based on articles cited in Pubmed up to January 2024.

Cardiac magnetic resonance imaging in detection of progressive graft dysfunction in pediatric heart transplantation

BACKGROUND

Chronic graft failure (CGF) in pediatric heart transplant (PHT) is multifactorial and may present with findings of fibrosis and microvessel disease (MVD) on endomyocardial biopsy (EMB). There is no optimal CGF surveillance method. We evaluated associations between cardiac magnetic resonance imaging (CMR) and historical/EMB correlates of CGF to assess CMR's utility as a surveillance method.

METHODS

Retrospective analysis of PHT undergoing comprehensive CMR between September 2015 and January 2022 was performed. EMB within 6 months was graded for fibrosis (scale 0-5) and MVD (number of capillaries with stenotic wall thickening per field of view). Correlation analysis and logistic regression were performed.

RESULTS

Forty-seven PHT with median age at CMR of 15.7 years (11.6, 19.3) and time from transplant of 6.4 years (4.1, 11.0) were studied. Cardiac allograft vasculopathy (CAV) was present in 11/44 (22.0%) and historical rejection in 14/41 (34.2%). CAV was associated with higher global T2 (49.0 vs. 47.0 ms; p = 0.038) and peak T2 (57.0 vs. 53.0 ms; p = 0.013) on CMR. Historical rejection was associated with higher global T2 (49.0 vs. 47.0 ms; p = 0.007) and peak T2 (57.0 vs. 53.0 ms; p = 0.03) as well as global extracellular volume (31.0 vs. 26.3%; p = 0.03). Higher fibrosis score on EMB correlated with smaller indexed left ventricular mass (rho = -0.34; p = 0.019) and greater degree of MVD with lower indexed left ventricular end-diastolic volume (rho = -0.35; p = 0.017).

CONCLUSION

Adverse ventricular remodeling and abnormal myocardial characteristics on CMR are present in PHT with CAV, historical rejection, as well as greater fibrosis and MVD on EMB. CMR has the potential use for screening of CGF.

Myocardial Oedema as a Consequence of Viral Infection and Persistence-A Narrative Review with Focus on COVID-19 and Post COVID Sequelae

Microvascular integrity is a critical factor in myocardial fluid homeostasis. The subtle equilibrium between capillary filtration and lymphatic fluid removal is disturbed during pathological processes leading to inflammation, but also in hypoxia or due to alterations in vascular perfusion and coagulability. The degradation of the glycocalyx as the main component of the endothelial filtration barrier as well as pericyte disintegration results in the accumulation of interstitial and intracellular water. Moreover, lymphatic dysfunction evokes an increase in metabolic waste products, cytokines and inflammatory cells in the interstitial space contributing to myocardial oedema formation. This leads to myocardial stiffness and impaired contractility, eventually resulting in cardiomyocyte apoptosis, myocardial remodelling and fibrosis. The following article reviews pathophysiological inflammatory processes leading to myocardial oedema including myocarditis, ischaemia-reperfusion injury and viral infections with a special focus on the pathomechanisms evoked by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In addition, clinical implications including potential long-term effects due to viral persistence (long COVID), as well as treatment options, are discussed.

Unveiling the Hidden Patterns: Multimodality Cardiac Imaging in Takotsubo Cardiomyopathy Diagnosis

Takotsubo cardiomyopathy, also known as stress cardiomyopathy, is a reversible form of cardiomyopathy characterized by reduced ejection fraction with regional wall motion abnormalities, elevated cardiac enzyme levels, and signs of ischemia on electrocardiogram despite the absence of obstructive epicardial coronary artery disease. It is often preceded by intense emotional or physical illness stressors. This case describes a 65-year-old female patient who likely developed takotsubo cardiomyopathy precipitated by the stress of diverticulitis.

Impact of cardiac troponin release and fluid resuscitation on outcomes of patients with sepsis

BACKGROUND

Septic patients are predisposed to myocardial injury manifested as cardiac troponin release (TnR). Prognostic significance and management implications of TnR and its relationship to fluid resuscitation and outcomes in the intensive care unit (ICU) setting has not been fully elucidated.

METHODS

A total of 24,778 patients with sepsis from eICU-CRD, MIMIC-III and MIMIC-IV databases were included in this retrospective study. In-hospital mortality and one-year survival were examined using multivariable regression analysis and Kaplan-Meier survival analysis with overlap weighting adjustment, as well as generalized additive models for fluid resuscitation.

RESULTS

TnR on admission was associated with higher in-hospital mortality [adjusted odds ratios (OR) = 1.33; 95% confidence interval (CI) = 1.23-1.43; p < 0.001 in unweighted analysis and adjusted OR = 1.39; 95% CI = 1.29-1.50; P < 0.001 with overlap weighting]. One-year mortality was higher in patients with admission TnR (P = 0.002). A trend was noted for association between admission TnR and 1-year mortality [adjusted OR = 1.16; 95% CI = 0.99-1.37; P = 0.067 in unweighted analysis] while the association was statistically significant after overlap weighting (adjusted OR = 1.25; 95% CI = 1.06-1.47; P = 0.008). Patients with admission TnR were less likely to benefit from more liberal fluid resuscitation. Adequate fluid resuscitation (80 ml/kg in the first 24 h of ICU stay) was associated with lower in-hospital mortality in septic patients without TnR but not in those with admission TnR.

CONCLUSIONS

Admission TnR is significantly associated with higher in-hospital mortality and 1-year mortality among septic patients. Adequate fluid resuscitation improves in-hospital mortality in septic patients without but not with admission TnR.