Background: The real impact of the degree of association (DoA) between endpoint components of a composite endpoint (CE) on sample size requirement (SSR) has not been explored. We estimate the impact of the DoA between death and acute myocardial infarction (AMI) on SSR of trials using use the CE of major adverse cardiac events (MACE). Methods: A systematic review and quantitative synthesis of trials that include MACE as the primary outcome through search strategies in MEDLINE and EMBASE electronic databases. We limited to articles published in journals indexed in the first quartile of the Cardiac & Cardiovascular Systems category (Journal Citation Reports, 2015–2020). The authors were contacted to estimate the DoA between death and AMI using joint probability and correlation. We analyzed the SSR variation using the DoA estimated from RCTs. Results: Sixty-three of 134 publications that reported event rates and the therapy effect in all component endpoints were included in the quantitative synthesis. The most frequent combination was death, AMI, and revascularization (n = 20; 31.8%). The correlation between death and AMI, estimated from 5 trials¸ oscillated between − 0.02 and 0.31. SSR varied from 14,602 in the scenario with the strongest correlation to 12,259 in the scenario with the weakest correlation; the relative impact was 16%. Conclusions: The DoA between death and AMI is highly variable and may lead to a considerable SSR variation in a trial including MACE.

Background. Iron deficiency (ID) is a significant, high-prevalence comorbidity in chronic heart failure (HF) that represents an independent predictor of a worse prognosis. However, a clear-cut diagnosis of ID in HF patients is not assured. The soluble transferrin receptor (sTfR) is a marker that reflects tissue-level iron demand and may be an early marker of ID. However, the impact of sTfR levels on clinical outcomes in non-anemic HF patients with a normal systemic iron status has never been evaluated. Methods. This is a post hoc analysis of an observational, prospective cohort study of 1236 patients with chronic HF of which only those with normal hemoglobin levels and a normal systemic iron status were studied. The final cohort consisted of 215 patients. Tissue ID was defined as levels of sTfR > 75th percentile (1.65 mg/L). Our aim was to describe the association between sTfR and clinical outcomes (all-cause death and HF hospitalization) and to explore its association with a wide array of serum biomarkers. Results. The sTfR level (HR 1.48, 95% CI 1.13–1.96, p = 0.005) and tissue ID (HR 2.14, 95% CI 1.22–3.75, p = 0.008) was associated with all-cause death. However, we found no association between sTfR levels and the risk of HF hospitalization. Furthermore, high sTfR levels were associated with a worse biomarker profile indicating myocardial damage (troponin and NT-proBNP), systemic inflammation (CRP and albumin), and impaired erythropoiesis (erythropoietin). Conclusions. In this cohort, the presence of tissue ID defined by sTfR levels is an independent factor for all-cause death in patients with normal systemic iron parameters.

Cardiogenic shock (CS) is a complex multifactorial clinical syndrome of end-organ hypoperfusion that could be associated with multisystem organ failure, presenting a diverse range of causes and symptoms. Despite improving survival in recent years due to new advancements, CS still carries a high risk of severe morbidity and mortality. Recent research has focused on improving early detection and understanding of CS through standardized team approaches, detailed hemodynamic assessment, and selective use of temporary mechanical circulatory support devices, leading to better patient outcomes. This review examines CS pathophysiology, emerging classifications, current drug and device therapies, standardized team management strategies, and regionalized care systems aimed at optimizing shock outcomes. Furthermore, we identify gaps in knowledge and outline future research needs.

Background: Endomyocardial fibrosis (EMF) is a challenging disease that leads to severe heart failure (HF) due to progressive fibrosis. Diet, parasitic infections, autoimmune disorders, and genetic predisposition have been advocated in EMF pathogenesis, and treatment options for EMF are limited with scarce evidence supporting heart transplantation (HTx). Case summary: A 38-year-old man was diagnosed with EMF with biventricular involvement. The diagnostic work-up ruled out eosinophilia, infections, and autoimmune conditions. The patient rapidly deteriorated, leading to cardiogenic shock with multiorgan failure, and an emergency HTx was performed. Three months later, the graft developed biventricular hypertrophy with atrial fibrosis and the endomyocardial biopsy (EMB) showed extensive inflammation and myocardial damage, compatible with Grade 2R (G3a) cellular rejection. After steroid pulses, the follow-up EMB reveals subendocardial fibrosis and microcalcifications, suggesting the possibility of an EMF recurrence. Nevertheless, the patient had a good clinical outcome, remaining asymptomatic with good graft function 2 years after the transplant. Discussion: This is the first reported case of suspected EMF recurrence following HTx. Given the unknown pathogenesis of EMF, close monitoring is crucial, though HTx appears to be a viable and successful treatment option for these patients.

Primary graft dysfunction (PGD) remains a major cause of early morbidity and mortality after a heart transplant (HTx). Understanding the donor-related mechanisms involved may help improve organ selection and post-HTx outcomes. This study aimed to explore the association between the donor serum biomarkers of cell death and inflammation and the incidence of PGD and rejection in HTx recipients. We conducted a retrospective, multicenter observational study of brain-dead (DBD) heart donors and corresponding recipients between 2013 and 2019. Donor blood samples were analyzed for inflammatory cytokines, cell death-related proteins, and mitochondrial (mtDNA) and genomic DNA (gDNA). A total of 39 donor–recipient pairs were included. Sixteen recipients developed severe PGD, and five experienced ≥2R cellular rejection. Donors whose recipients developed PGD had significantly lower serum Caspase-3 levels compared to those without PGD (391.6 [101.8–1003.3] vs. 65.3 [40.2–163.3] pg/mL; p = 0.04). A trend toward lower mtDNA/gDNA ratio was also observed in the same group (10.5 [5.4–24.6] vs. 6.5 [3.3–10.7]; p = 0.067). Lower Caspase-3 levels in donor serum were significantly associated with the development of severe PGD in recipients. This may suggest that the sublethal activation of apoptotic pathways in the donor could play a protective role, potentially conditioning the graft to tolerate ischemic injury.