Pulmonary Hemorrhage following Edge-to-Edge Mitral Valve Repair

Mitral valve repair with the MitraClip device has emerged as an effective treatment option for patients with severe mitral regurgitation and contraindications for surgical interventions. While the procedure is not known to cause pulmonary complications, we describe two cases of pulmonary hemorrhage following percutaneous mitral valve repair. The patients did well with supportive care and reinitiation of anticlotting agents was well tolerated after resolution of bleeding

Altered Maturation Status and Possible Immune Exhaustion of CD8 T Lymphocytes in the Peripheral Blood of Patients Presenting With Acute Coronary Syndromes

OBJECTIVE: Inflammation in response to oxidized lipoproteins is believed to play a key role in acute coronary syndromes (ACS), but the pattern of immune activation has not been fully characterized. We sought to perform detailed phenotypic and functional analysis of CD8 T lymphocytes from patients presenting with ACS to determine activation patterns and potential immunologic correlates of ACS. APPROACH AND RESULTS: We used polychromatic flow cytometry to analyze the cytokine production profiles of naïve, effector, and memory CD8 T cells in patients with ACS compared to control subjects with stable coronary artery disease. ACS was associated with an altered distribution of circulating CD8+ T cell maturation subsets with reduced proportions of naïve cells and expansion of effector memory cells. ACS was also accompanied by impaired interleukin (IL)-2 production by phenotypically naïve CD8 T cells. These results were validated in a second replication cohort. Naïve CD8 cells from ACS patients also had increased expression of programmed cell death (PD)-1, which correlated with IL-2 hypoproduction. In vitro, stimulation of CD8 T cells with oxidized low density lipoprotein (ox-LDL) was sufficient to cause PD-1 upregulation and diminished IL-2 production by naïve CD8 T cells. CONCLUSIONS: In this exploratory analysis, naïve CD8+ T cells from ACS patients show phenotypic and functional characteristics of immune exhaustion: impaired IL-2 production and PD-1 upregulation. Exposure to ox-LDL recapitulates these features in vitro. These data provide the first evidence that ox-LDL could play a role in immune exhaustion and that this immunophenotype may be a biomarker for ACS