Comparison of Routine Versus Selective Glycoprotein IIb/IIIa Inhibitors Usage in Primary Percutaneous Coronary Intervention (from the British Cardiovascular Interventional Society).

The role of glycoprotein IIb/IIIa inhibitors (GPI) in primary percutaneous coronary intervention (PPCI) remains uncertain. Previous analyses compare PPCI outcomes with clopidogrel plus GPI, versus without GPI. This does not reflect modern contemporary PPCI practice with ticagrelor or prasugrel. Nor does it answer the important question faced daily by PPCI operators: should GPI be used routinely or selectively? We aim to determine whether a strategy of routine use of GPI in contemporary PPCI practice is superior to selective GPI use. A total of 110,327 consecutive PPCIs performed in England were prospectively recorded in the British Cardiovascular Intervention Society Database (2009 to 2015). The cohort was divided into routine and selective GPI usage groups based on the PPCI operator's strategy, defined as GPI used in >75% and <25% PPCIs, respectively. Overall, GPI use declined from 73.1% to 43.3% of PPCIs. Routine compared with selective GPI usage was associated with lower all-cause 1-year mortality: 9.7% versus 11.0%, p < 0.001. There was a consistent survival benefit for routine GPI usage as compared with selective GPI usage: univariable analysis (hazard ratio = 0.88 [95% confidence interval 0.83 to 0.93], p < 0.001), multivariable analysis (hazard ratio = 0.82 [0.77 to 0.88], p < 0.001). For survival, there was no interaction between GPI usage and the type of P2Y12-inhibitor used. In conclusion, a strategy of routine GPI usage in patients who underwent PPCI was associated with lower all-cause mortality as compared with selective GPI usage. This benefit was maintained despite 44.3% of patients receiving prasugrel or ticagrelor.

Management of immune thrombocytic purpura and acute coronary syndrome: A double-edged sword!

Treating patients known to have immune thrombocytopenic purpura (ITP) presenting with acute coronary syndrome (ACS) pose challenges, especially if they undergo percutaneous coronary intervention and stenting, as they require certain period of dual anti-platelet medication based up on the type of stent been deployed. Co-existence of therapies to increase platelet number as well as anti-platelet efficacy at the same time appears contradictory; imbalance in antagonistic treatment approach of increasing platelet number to treat ITP and inhibiting their activity to treat ACS can result in life threatening complications.

Recurrent ST Elevation Myocardial Infarction: What is the Aetiology?

Coronary artery disease is a leading cause of morbidity and mortality in the western world. Plaque rupture in an atherosclerotic lesion is the most commonly encountered underlying pathophysiology. Spontaneous coronary dissection can have similar presentation, but we as a community of cardiologists may not be aware of uncommon aetiologies, such as vasculitis presenting as ST elevation myocardial infarction (STEMI). Here we present a case report of a lady, who presented with STEMI on three occasions within five days, due to underlying granulomotosis with polyangiitis (GPA).

Patients undergoing PCI from the femoral route by default radial operators are at high risk of vascular access-site complications.

AIMS: Radial artery (RA) access for PCI has a lower incidence of vascular access-site (VAS) complications than the femoral artery (FA) approach. However, even for default radial operators certain patients are intervened upon from the FA. We examined the demographics and incidence of VAS complications when default radial operators resort to the FA for PCI. METHODS AND RESULTS: The demographics and VAS complications were compared by access site retrospectively for all PCI cases performed by default radial operators (n=1,392). A modified ACUITY trial definition of major VAS complication was used. FA puncture occurred in 25.2% (351/1,392) of cases. Patients were more likely to be female, older and weigh less than patients undergoing PCI from the RA. The FA procedure was likely to be more complex with larger sheaths, more left main stem, graft and multivessel intervention, and there was a greater proportion of emergency cases. Despite increased case complexity, glycoprotein inhibitors were used less frequently in femoral cases (26.5% vs. 36.8%, p<0.001). A VAS complication occurred in 12.5% (44/351) of cases. CONCLUSIONS: The risk factors for access-site bleeding are disproportionately high in the population requiring FA puncture by default radial operators, and as a result such patients have a high rate of vascular access-site complications.

CD8+ T lymphocytes regulate the arteriogenic response to ischemia by infiltrating the site of collateral vessel development and recruiting CD4+ mononuclear cells through the expression of interleukin-16.

BACKGROUND: Previous studies have demonstrated that macrophages and CD4+ T lymphocytes play pivotal roles in collateral development. Indirect evidence suggests that CD8+ T cells also play a role. Thus, after acute cerebral ischemia, CD8+ T cells infiltrate the perivascular space and secrete interleukin-16 (IL-16), a potent chemoattractant for monocytes and CD4+ T cells. We tested whether CD8+ T lymphocytes contribute to collateral vessel development and whether the lack of circulating CD8+ T cells prevents IL-16 expression, impairs CD4+ mononuclear cell recruitment, and reduces collateral vessel growth after femoral artery ligation in CD8(-/-) mice. METHODS AND RESULTS: After surgical excision of the femoral artery, laser Doppler perfusion imaging demonstrated reduced blood flow recovery in CD8(-/-) mice compared with C57/BL6 mice (ischemic/nonischemic limb at day 28, 0.66+/-0.04 versus 0.87+/-0.04, respectively; P<0.01). This resulted in greater calf muscle atrophy (mean fiber area, 785+/-68 versus 1067+/-69 microm2, respectively; P<0.01) and increased fibrotic tissue content (10.8+/-1.2% versus 7+/-1%, respectively; P<0.01). Moreover, CD8(-/-) mice displayed reduced IL-16 expression and decreased CD4+ T-cell recruitment at the site of collateral vessel development. Exogenous CD8+ T cells, infused into CD8(-/-) mice immediately after femoral artery ligation, selectively homed to the ischemic hind limb and expressed IL-16. The restoration of IL-16 expression resulted in significant CD4+ mononuclear cell infiltration of the ischemic limb, faster blood flow recovery, and reduced hindlimb muscle atrophy/fibrosis. When exogenous CD8+ T cells deficient in IL-16 (IL-16(-/-)) were infused into CD8(-/-) mice immediately after femoral artery ligation, they selectively homed to the ischemic hind limb but were unable to recruit CD4+ mononuclear cells and did not improve blood flow recovery. CONCLUSIONS: These results demonstrate that CD8+ T cells importantly contribute to the early phase of collateral development. After femoral artery ligation, CD8+ T cells infiltrate the site of collateral vessel growth and recruit CD4+ mononuclear cells through the expression of IL-16. Our study provides further evidence of the significant role of the immune system in modulating collateral development in response to peripheral ischemia.

Impact of sirolimus-eluting stents on outcomes of patients treated for acute myocardial infarction by primary angioplasty.

Sirolimus-eluting stents (SESs) are currently being used in patients undergoing percutaneous coronary intervention (PCI). SESs have not been evaluated in the treatment of acute myocardial infarction by primary angioplasty. We report our initial experience with SESs implanted during primary angioplasty. One hundred and three patients were treated within 12 hr after onset of acute myocardial infarction (AMI) with primary angioplasty and SES implantation. Those patients were compared to 504 patients treated with bare metal stents (BMSs). Angiographic success (TIMI flow grade 3 and residual stenosis < 50%) was completed in 98% of patients with SESs and no subacute stent thrombosis was reported. In-hospital outcomes were similar in the SES and BMS groups. At 6 months, major cardiac events were less frequent in the SES group than in the BMS group (9% vs. 24%, respectively; P < 0.001), driven by a lesser need for repeat revascularization with SESs (1% vs. 10.3% with BMSs; P = 0.014). Mortality at 6 months was 7% with SESs and 11% with BMSs (P = 0.14). SESs are safe and effective for the treatment of AMI by primary angioplasty. As compared to BMSs, SESs improve long-term outcome after AMI, mainly by reducing the need for repeat revascularization.

Late thrombosis in drug-eluting coronary stents after discontinuation of antiplatelet therapy.

Although the safety profiles of coronary stents eluting sirolimus or paclitaxel do not seem to differ from those of bare metal stents in the short-to-medium term, concern has arisen about the potential for late stent thromboses related to delayed endothelialisation of the stent struts. We report four cases of angiographically-confirmed stent thrombosis that occurred late after elective implantation of polymer-based paxlitaxel-eluting (343 and 442 days) or sirolimus-eluting (335 and 375 days) stents, and resulted in myocardial infarction. All cases arose soon after antiplatelet therapy was interrupted. If confirmed in systematic long-term follow-up studies, our findings have potentially serious clinical implications.

Temporal patterns of gene expression after acute hindlimb ischemia in mice: insights into the genomic program for collateral vessel development.

OBJECTIVES: We sought to understand the genomic program leading to collateral vessel formation. BACKGROUND: Recently, technology has advanced to the point that it is now possible to elucidate the large array of genes that must be expressed, as well as the temporal expression pattern, for the development of functionally important collateral vessels. In this investigation, we used deoxyribonucleic acid array expression profiling to determine the time course of differential expression of 12,000 genes after femoral artery ligation in C57BL/6 mice. METHODS: Ribonucleic acid was extracted from the adductor muscle, which showed no signs of ischemia. Sampling was at baseline, 6 h, and 1, 3, 7, and 14 days after femoral artery ligation or sham operation. RESULTS: Femoral artery ligation caused the differential expression (>2-fold) of 783 genes at one or multiple time points: 518 were induced and 265 were repressed. Cluster analysis generated four temporal patterns: 1) early upregulated (6 to 24 h)-immediate early transcriptional factors, angiogenesis, inflammation, and stress-related genes; 2) mid-phase upregulated (day 3)-cell cycle and cytoskeletal and inflammatory genes; 3) late upregulated (days 7 to 14)-angiostatic, anti-inflammatory, and extracellular matrix-associated genes; and 4) downregulated-genes involved in energy metabolism, water channel, and muscle contraction. Microarray data were validated using quantitative reverse transcription polymerase chain reaction. CONCLUSIONS: This study documents the large number of genes whose differential expression and temporal functional clustering appear to contribute to collateral formation. These results can serve as a genomic model for arteriogenesis and as a database for developing new therapeutic strategies.

Late thrombosis in cypher stents after the discontinuation of antiplatelet therapy.

Drug-eluting stents, since their approval in the United States, have become the treatment of choice for de novo coronary artery narrowing due to their ability to reduce restenosis and the need for repeat revascularization. We present two patients who underwent percutaneous coronary intervention for the treatment of multivessel coronary artery disease; both patients were treated with sirolimus-eluting stents (SES) and bare metal stents (BMS).

Akt controls vascular smooth muscle cell proliferation in vitro and in vivo by delaying G1/S exit.

Constitutive activation of serine/threonine kinase Akt causes uncontrolled cell-cycle progression in different cell types and in malignancy. To investigate how Akt activation modulates cell-cycle progression in vascular smooth muscle cells (SMCs) in vitro and in the intact animal, we inhibited Akt-dependent signaling by adenovirus-mediated transfection of a dominant-negative Akt mutant (AA-Akt). We observed reduced proliferation rate (P<0.01), DNA synthesis (P<0.01), and a significant arrest in G1/S exit (P<0.01) both in vitro in response to serum stimulation and in vivo after vascular injury. In vivo transfection of the balloon-injured vessel with AA-Akt reduced SMC proliferation, resulting in decreased neointima compared with control virus (P<0.01). These effects were at least in part modulated, both in vitro and in vivo, by increased p21Cip1 expression, as demonstrated by lack of effect of AA-Akt on cell proliferation in p21-/- mouse SMCs. In conclusion, this study demonstrates that Akt-dependent signaling enhances cell-cycle progression of nontransformed SMCs in vitro and in response to vascular injury in the intact animal. These results suggest a role for Akt signaling in modulating the response of normal tissues to stress and the response of the arterial wall to acute and possibly repetitive injuries that ultimately contribute to restenosis and atherosclerosis.

Incidence, predictors, and prognostic implications of bleeding and blood transfusion following percutaneous coronary interventions.

Bleeding related to percutaneous coronary intervention (PCI) occurs relatively frequently. We retrospectively investigated the incidence, predictors, and prognostic impact of periprocedural bleeding and transfusion in 10,974 patients who underwent PCI. Bleeding definitions were based on Thrombolysis In Myocardial Infarction (TIMI) criteria: (1) major bleeding (n = 588; 5.4%): if patients had a hemorrhagic stroke or if hematocrit decreased >15 points or by 10 to 15 points with clinical bleeding; (2) minor bleeding (n = 1,394; 12.7%): if hematocrit decreased <10 points with clinical bleeding or by 10 to 15 points without clinical bleeding; and (3) no bleeding (n = 8,992; 81.9%): if hematocrit decreased <10 points without clinical bleeding. Patients with major bleeding were older than patients with minor or no bleeding (67.8 +/- 11 vs 65.9 +/- 11 vs 63.6 +/- 11 years, respectively; p <0.001) and more often experienced intraprocedural complications, such as emergency use of an intra-aortic balloon pump (13.6% vs 6.5% vs 2.3%, respectively; p <0.001). Multivariate logistic regression analysis identified the use of an intra-aortic balloon pump (odds ratio [OR] 3.0, p <0.0001), procedural hypotension (OR 2.9, p <0.001), and age >80 years (OR 1.9 compared with age <50 years, p = 0.001) as the strongest predictors for major bleeding. Patients who had major bleeding had higher in-hospital and 1-year mortality compared with patients with minor or no bleeding. Bleeding was an independent predictor of in-hospital death. Thus, periprocedural major bleeding occurs relatively frequently and is associated with adverse outcomes. Patients >80 years of age who experience intraprocedural complications are at particularly high risk.

Impaired arteriogenic response to acute hindlimb ischemia in CD4-knockout mice.

BACKGROUND: T lymphocytes, components of the immune and inflammatory systems, are involved in such normal processes as wound healing and host defense against infection and in such pathological processes as tumor growth and atherosclerotic plaque development. Angiogenesis is a mechanism common to each. Because CD4+ T lymphocytes are active in regulating humoral and cellular responses of the immune system, we determined whether CD4+ cells contribute to collateral vessel development by using the mouse ischemic hindlimb model. METHODS AND RESULTS: One week after ischemia, CD4-/- mice showed reduced collateral flow induction, macrophage number, and vascular endothelial growth factor levels in the ischemic muscle compared with wild-type mice. There was also delayed recovery of hindlimb function and increased muscle atrophy/fibrosis. Spleen-derived purified CD4+ T cells infused into CD4-/- mice selectively localized to the ischemic limb and significantly increased collateral flow as well as macrophage number and vascular endothelial growth factor levels in the ischemic muscle. Muscle function and damage also improved. CONCLUSIONS: These results indicate an important role of CD4+ cells in collateral development, as demonstrated by a 25% decrease in blood flow recovery after femoral artery ligation. Our data also suggest that CD4+ T cells control the arteriogenic response to acute hindlimb ischemia, at least in part, by recruiting macrophages to the site of active collateral artery formation, which in turn triggers the development of collaterals through the synthesis of arteriogenic cytokines.

Stroke complicating percutaneous coronary interventions: incidence, predictors, and prognostic implications.

BACKGROUND: Stroke associated with percutaneous coronary intervention (PCI) is an infrequent although devastating complication. We investigated the incidence, predictors, and prognostic impact of periprocedural stroke in unselected patients undergoing PCI. METHODS AND RESULTS: A total of 9662 patients who underwent 12 407 PCIs between January 1990 and July 1999 were retrospectively studied. Stroke was diagnosed in 43 patients (0.38% of procedures). Patients with stroke were older (72+/-11 versus 64+/-11 years, P<0.001), had lower left ventricular ejection fraction (42+/-12 versus 46+/-13%, P=0.04) and more diabetes (39.5% versus 27.2%, P=0.07), and experienced a higher rate of intraprocedural complications necessitating emergency use of intra-aortic balloon pump (IABP) (23.3% versus 3.3%, P<0.001). In-hospital mortality (37.2% versus 1.1%, P<0.001) and 1-year mortality (56.1% versus 6.5%, P<0.001) were higher in patients with stroke. Compared with hemorrhagic stroke, patients with ischemic stroke had higher rate of in-hospital major adverse cardiac events (57.1% versus 25%, P=0.037). Multivariate logistic regression analysis identified emergency use of IABP as the strongest predictors for stroke (OR=9.6, CI 3.9 to 23.9, P<0.001), followed by prophylactic use of IABP (OR=5.1), age >80 years (OR=3.2, compared with age <50 years), and vein graft intervention (OR=2.7). CONCLUSIONS: Stroke associated with contemporary PCI is associated with substantial increased mortality. Elderly patients who experience intraprocedural complications necessitating the use of IABP are at particularly high risk.