ABSTRACT
Background: Coronary artery bypass graft (CABG) surgery represents a major cardiovascular operation and may be associated with post-operative ST-elevation myocardial infarction (STEMI) due to graft failure. This is challenging to diagnose and treat as the implanted grafts may be prone to complications when treated percutaneously with drug-eluting stents. Case summary: A man in his 60â s underwent CABG and developed new persistent ST elevations of 2â mm in anterior leads with no significant chest pain, although, administered with intravenous opiates post-operatively. Transthoracic echocardiography was non-diagnostic. Invasive angiography performed emergently showed a thrombotic occlusion of the mid-left anterior descending artery at the site of the anastomosis with the left internal mammary artery (LIMA) graft. Intervention via the graft was considered high risk of complications, therefore, native coronary arteries were used to approach the occlusion, which was successfully cleared with a combination balloon angioplasty with a semi-compliant and then a drug-eluting balloon. The LIMA started working again with the resolution of ST elevation and no immediate complications. Discussion: Early post-operative ST elevations in continuous leads should not be ignored as they often may be the only feature of new-onset STEMI. Drug-eluting balloons represent a feasible and possibly safer option than drug-eluting stents to treat these conditions.
ABSTRACT
B lymphocytes producing antiplatelet autoantibodies play a major role in autoimmune thrombocytopenia (ITP). However, certain B cells, including the human CD19(+)CD24(hi)CD38(hi) subpopulation, possess regulatory functions mediated partly by IL-10. In a cohort of chronic ITP patients with low platelet counts who consisted of patients off treatment, we found a lower frequency of CD19(+)CD24(hi)CD38(hi) in the peripheral compartment of nonsplenectomized patients (P = .03). IL-10 expression after activation was decreased in all ITP circulating CD19(+) subpopulations (P < .03), and inhibition of monocyte TNF-α expression by activated B cells was reduced in patients with platelet numbers of < 50 × 10(9) cells/L (P = .001), indicating that regulatory B cells of patients with ITP are functionally impaired in their ability to dampen monocyte activation. Interestingly, in nonsplenectomized patients whose platelet counts were elevated after treatment with thrombopoietic agents, the frequency of CD19(+)CD24(hi)CD38(hi) B cells was increased compared with those before treatment (P = .02). Altogether, these data indicate a compromised regulatory B-cell compartment as an additional defect in immune regulation in patients with chronic ITP that may be restored in responders to thrombopoietic treatment.
