Impact of Access Site on Periprocedural Bleeding and Cerebral and Coronary Events in High-Bleeding-Risk Percutaneous Coronary Intervention: Findings from the RIVA-PCI Trial.

INTRODUCTION: The preference for using transradial access (TRA) over transfemoral access (TFA) in patients requiring percutaneous coronary intervention (PCI) is based on evidence suggesting that TRA is associated with less bleeding and fewer vascular complications, shorter hospital stays, improved quality of life, and a potential beneficial effect on mortality. We have limited study data comparing the two access routes in a patient population with atrial fibrillation (AF) undergoing PCI, who have a particular increased risk of bleeding, while AF itself is associated with an increased risk of thromboembolism. METHODS: Using data from the RIVA-PCI registry, which includes patients with AF undergoing PCI, we analyzed a high-bleeding-risk (HBR) cohort. These patients were predominantly on oral anticoagulants (OAC) for AF, and the PCI was performed via radial or femoral access. Endpoints examined were in-hospital bleeding (BARC 2-5), cerebral events (TIA, hemorrhagic or ischemic stroke) and coronary events (stent thrombosis and myocardial infarction). RESULTS: Out of 1636 patients, 854 (52.2%) underwent TFA, while 782 (47.8%) underwent the procedure via TRA, including nine patients with brachial artery puncture. The mean age was 75.5 years. Groups were similar in terms of age, sex distribution, AF type, cardiovascular history, risk factors, and comorbidities, except for a higher incidence of previous bypass surgeries, heart failure, hyperlipidemia, and chronic kidney disease (CKD) with a glomerular filtration rate (GFR) < 60 ml/min in the TFA group. No clinically relevant differences in antithrombotic therapy and combinations were present at the time of PCI. However, upon discharge, transradial PCI patients had a higher rate of triple therapy, while dual therapy was preferred after transfemoral procedures. Radial access was more frequently chosen for non-ST-segment elevation myocardial infarction (NSTEMI) and unstable angina pectoris (UAP) cases (NSTEMI 26.6% vs. 17.0%, p < 0.0001; UAP 21.5% vs. 14.5%, p < 0.001), while femoral access was more common for elective PCI (60.3% vs. 44.1%, p < 0.0001). No differences were observed for ST-segment elevation myocardial infarction (STEMI). Both groups had similar rates of cerebral events (TFA 0.2% vs. TRA 0.3%, p = 0.93), but the TFA group had a higher incidence of bleeding (BARC 2-5) (4.2% vs. 1.5%, p < 0.01), mainly driven by BARC 3 bleeding (1.5% vs. 0.4%, p < 0.05). No significant differences were found for stent thrombosis and myocardial infarction (TFA 0.2% vs. TRA 0.3%, p = 0.93; TFA 0.4% vs. TRA 0.1%, p = 0.36). CONCLUSIONS: In HBR patients with AF undergoing PCI for acute or chronic coronary syndrome, the use of TRA might be associated with a decrease in in-hospital bleeding, while not increasing the risk of embolic or ischemic events compared to femoral access. Further studies are required to confirm these preliminary findings.

Current status of antithrombotic therapy and in-hospital outcomes in patients with atrial fibrillation undergoing percutaneous coronary intervention in Germany.

BACKGROUND: Little is known about current patterns of antithrombotic therapy in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) in clinical practice in Germany. METHODS: The RIVA-PCI is a prospective, non-interventional, multicenter study with follow-up until hospital discharge including consecutive patients with AF undergoing PCI. RESULTS: Between January 2018 and March 2020, 1636 patients (elective in 52.6%, non-ST elevation acute coronary syndrome [NSTE-ACS] in 39.3%, ST-elevation myocardial infarction in 8.2%) from 51 German hospitals were enrolled in the study. After PCI a dual antithrombotic therapy (DAT) consisting of OAC and a P2Y12 inhibitor was given to 66.0%, triple antithrombotic therapy (TAT) to 26.0%, dual antiplatelet therapy to 5.5%, and a mono-therapy to 2.5% of the patients. Non-vitamin K antagonist oral anticoagulants (NOACs) were given to 82.4% and vitamin K antagonists to 11.5% of the patients. In-hospital events included death in 12 cases (0.7%), myocardial infarction, stent thrombosis, and ischemic stroke in four (0.2%) patients each, while 2.8% of patients had bleeding complications. The recommended durations for DAT or TAT at discharge were 1 month (1.5%), 3 months (2.1%), 6 months (43.1%), and 12 months (45.6%), with a 6-month course of DAT (47.7%) most often recommended after elective PCI and a 12-month course of DAT (40.1%) after ACS. CONCLUSION: The preferred therapy after PCI in patients with AF is DAT with a NOAC and clopidogrel. In-hospital ischemic and bleeding events were rare. The recommended durations for combination therapy vary considerably.

Rivaroxaban in Patients With Atrial Fibrillation Who Underwent Percutaneous Coronary Intervention in Clinical Practice.

Little is known about the efficacy and safety of rivaroxaban in patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) in clinical practice. We therefore conducted a prospective observational study to determine the rate of ischemic, embolic, and bleeding events in patients with AF and PCI treated with rivaroxaban in a real-world experience. The RIVA-PCI ("rivaroxaban in patients with AF who underwent PCI") (clinicaltrials.gov NCT03315650) is a prospective, noninterventional, multicenter study with a follow-up until 14 months, including patients with AF who underwent PCI discharged with rivaroxaban. Between January 2018 and March 2020, 700 patients with PCI treated with rivaroxaban (elective in 50.1%, non-ST-elevation acute coronary syndrome 43.0%, ST-elevation myocardial infarction in 6.9%) were enrolled at 51 German hospitals. After PCI, a dual antithrombotic therapy consisting of rivaroxaban and a P2Y12 inhibitor was administered in 70.7% and triple antithrombotic therapy in 27.9%, respectively. Follow-up information could be obtained in 695 patients (99.3%). Rivaroxaban has been stopped prematurely in 21.6% of patients. Clinical events under rivaroxaban during the 14-month follow-up compared with those observed in the PIONEER-AF PCI trial included cardiovascular death (2.0% % vs 2.0%), myocardial infarction (0.9% vs 3.0%), stent thrombosis (0.2% vs 0.8%), stroke (1.3% vs 1.3%), International Society on Thrombosis and Haemostasis major (4.2% vs 3.9%), and International Society on Thrombosis and Haemostasis nonmajor clinically relevant bleeding (15.3% vs 12.9%). Therefore, in this real-world experience, rivaroxaban in patients with AF who underwent PCI is associated with ischemic and bleeding event rates comparable with those observed in the randomized PIONEER-AF PCI trial.

Clinical outcomes in unselected patients treated with the PROMUS Element platinum-chromium, everolimus-eluting stent: Final five-year results from the PE PROVE Study.

OBJECTIVES: The goal of this analysis was to evaluate the final 5-year safety and effectiveness of the PROMUS Element platinum-chromium everolimus-eluting stent in unselected patients treated in routine clinical practice. BACKGROUND: The prospective, open-label PROMUS Element™ European Post-Approval Surveillance Study (PE-PROVE) enrolled 1,010 "real-world" patients who received the PROMUS Element stent. Adverse event rates were low at 1-year, and the incidence of stent thrombosis was 0.6%. METHODS: The primary endpoint was target vessel failure (TVF; overall and PE stent-related), a composite of cardiac death, myocardial infarction (MI) related to the target vessel, or target vessel revascularization (TVR) at 1-year post-implantation. Five-year clinical outcomes were evaluated in overall as well as high-risk patient subgroups. RESULTS: The overall 5-year TVF rate was 14.9%, with 7.0% being related to the study stent. Cardiac death, MI and TVR related to the study stent occurred in 0.5%, 3.2%, and 5.7%, respectively. Stent thrombosis through 5-year follow-up was 1.0%. The rates of overall and study stent related TVF were numerically higher in patients with medically treated diabetes, long lesions (≥28 mm), and small diameter vessels (≤2.5 mm) compared to the overall study population. Additionally, favorable stent thrombosis rates through 5 years were reported for the PROMUS Element stent in these high-risk subgroups. CONCLUSIONS: The final 5-year data from the PE-PROVE study demonstrate favorable outcomes and low rates of adverse events with the PE stent when used in "real-world" patients with coronary artery disease.

Use, efficacy and safety of prasugrel in patients with ST segment elevation myocardial infarction scheduled for primary percutaneous coronary intervention in clinical practice. Results of the prospective ATACS-registry.

BACKGROUND: Prasugrel compared to clopidogrel has been shown to improve outcome in patients with ST elevation myocardial infarction (STEMI) in the TRITON-TIMI 38 trial. Little is known about the use, efficacy and safety of prasugrel in patients with STEMI in clinical practice. METHODS: We conducted a prospective registry including patients with STEMI scheduled for primary percutaneous coronary intervention (PCI). Between October 2009 and February 2013 a total of 3291 patients with STEMI receiving a loading dose of either clopidogrel or prasugrel were included in this analysis. RESULTS: Prasugrel was predominantly used in patients <75 years, body weight >60 kg and those without prior stroke. In-hospital mortality was numerically lower in the prasugrel group (1.7% vs. 4.4%), as well as non-fatal reinfarction (0.2% vs. 0.5%), non-fatal stroke (0.1% vs. 0.3%) and major cardiac and cerebrovascular events (MACCE) (2.1% vs. 5.2%), while there was no difference in major bleeding complications (0.8% vs. 0.9%). In the multivariate analysis the MACCE-rate tended to be lower in prasugrel treated patients (odds ratio 0.71, 95% confidence intervals 0.42-1.08) but bleeding-rates tended to be higher. CONCLUSIONS: In this real life experience in patients with STEMI scheduled for primary PCI, prasugrel was almost exclusively used in the label-recommended patient population and tended to be more effective but associated with more bleedings compared to clopidogrel. These results support the findings in the STEMI population in the randomized TRITON-TIMI 38 study.

One-year outcomes in 1,010 unselected patients treated with the PROMUS Element everolimus-eluting stent: the multicentre PROMUS Element European Post-Approval Surveillance Study.

AIMS: The PROMUS™ Element™ European Post-Approval Surveillance Study (PE-Prove) is a prospective, open-label, multicentre observational study designed to assess outcomes following PROMUS Element everolimus-eluting stent implantation in an unselected patient population. METHODS AND RESULTS: A total of 1,010 patients were enrolled at 40 clinical sites in Europe, including 24.9% with medically treated diabetes, 50.0% with Type B2/C lesions, 6.1% with chronic total occlusion, 17.8% with acute myocardial infarction (MI ≤24 hours pre-procedure), and 20.1% with unstable angina. The target lesion was the culprit for ST-segment elevation MI in 7.3% of patients. The one-year, per patient target vessel failure rate was 6.2% (60/975), 3.4% (33) being related to the PROMUS Element stent. Rates of cardiac death, MI, and Academic Research Consortium (ARC) definite/probable stent thrombosis were 1.7%, 3.5%, and 0.6%, respectively. The target vessel revascularisation rate was 3.2% (31/975), 2.1% (20) being related to the PROMUS Element stent. CONCLUSIONS: In a large and relatively complex group of "real-world" patients, coronary artery revascularisation with the PROMUS Element everolimus-eluting stent provides favourable results with low event rates consistent with those reported for other contemporary drug-eluting stents.

Prolonged clopidogrel application reduces tissue factor expression after percutaneous coronary intervention in the porcine model.

BACKGROUND: Late thrombotic events are important complications associated with intracoronary brachytherapy (ICBT) using ionizing radiation (IR) or with antiproliferative treatment modalities such as drug-eluting stents (DES). The mechanism mediating these thrombotic events is not well understood. This study assessed the effect of prolonged clopidogrel treatment on tissue factor (TF) expression in coronary arteries and on the circulating TF level after percutaneous transluminal coronary angioplasty /ICBT in a porcine coronary model. METHODS: Pigs were treated with aspirin plus a 300 mg loading dose of clopidogrel one day before percutaneous coronary intervention (PCI), followed by a daily dose of clopidogrel and aspirin. During PCI one of the two balloon-injured arteries was treated by brachytherapy. Animals were sacrificed at different time points. The pigs, which were sacrificed 3 months post-PCI, were divided into two groups (Group I: clopidogrel for 3 months; Group II: clopidogrel for 1 month). Plasma TF was measured by enzyme-linked immunosorbent assay in blood samples taken from all pigs before and immediately after intervention and before sacrifice. Morphometric analysis was performed on digitalized images employing the software LUCIA G for TF staining. Vascular TF expression levels were assessed by quantitative real-time polymerase chain reaction. RESULTS: Prolonged clopidogrel application significantly reduced coronary TF at the protein (Group I vs. II, 8.975 ± 3.947% vs. 26.44 ± 5.375%, P = .007) and mRNA level [Group I vs. II, (0.3501 ± 0.0519) × 10(-3) vs. (0.7073 ± 0.0436) × 10(-3), P<.0005]. Circulating TF protein tended to be lower after 3 months than after 1 month clopidogrel treatment post-PCI (Group I vs. Group II, 488.3 ± 35.37 pg/ml vs. 572.3 ± 39.9 pg/ml, P = .130). CONCLUSIONS: Prolonged clopidogrel treatment reduced coronary TF expression and tended to reduce the blood TF level post-PCI, thus possibly modulating the risk of late thrombosis.

Effect of interleukin-15 on the course of myocarditis in Coxsackievirus B3-infected BALB/c mice.

OBJECTIVE: Cytokines have an important role in both the initiation and perpetuation of viral myocarditis. Because a causative therapy of myocarditis is not yet well established and immunomodulation is a promising approach, the influence of interleukin (IL)-15, a proinflammatory cytokine, on the course of experimental myocarditis in Coxsackievirus B3 (CVB3)-infected mice was examined. METHODS: Hearts from CVB3-infected (n=14), sham-infected (n=14) and CVB3-infected BALB/c mice treated with IL-15 (n=6) or a competitive IL-15 fusion protein (n=6) were analyzed for hemodynamic function, cellular infiltrates and myocardial collagen content. RESULTS: Induction of myocarditis was associated with significant loss of body and heart weight, decreased left ventricular function, and increased collagen content and cellular infiltrates in the myocardium. Treatment of infected animals with IL-15 resulted in normalization of body and heart weight, and significantly improved systolic and diastolic left ventricular function, comparable with that of uninfected animals. This was paralleled by a significant reduction of myocardial collagen content to levels observed in animals without disease and by markedly reduced cellular infiltration of lymphocytes and macrophages in the myocardium. Inhibition of intrinsic IL-15 with IL-15 fusion protein tended to aggravate the disease. CONCLUSIONS: Treatment with IL-15 has a positive effect on CVB3- induced murine myocarditis and seems to be a promising approach to modifying clinical course, hemodynamics and histopathology of virus-induced myocarditis. Further studies are needed to identify the underlying mechanisms.

Complex porcine model of atherosclerosis: induction of early coronary lesions after long-term hyperlipidemia without sustained hyperglycemia.

BACKGROUND: The incidence of coronary artery disease (CAD) is still increasing in industrialized countries and it is even higher in diabetic patients. For experimental studies investigating the pathophysiology of CAD, the use of an animal model comparable with the pathological situation in patients is crucial. OBJECTIVE: To develop a model of advanced coronary atherosclerosis with induction of hyperlipidemia and hyperglycemia in domestic pigs. METHODS: Six pigs were fed a standard pig chow (controls), two were fed a 2% cholesterol and 17% coconut fat diet (Chol group), and two pigs received a 4% cholesterol and 17% coconut fat diet combined with streptozotocin (STZ) injections to induce diabetes (High Chol+STZ group). Serum lipid and plasma glucose values were analyzed, and histochemical staining for morphometric analysis and immunohistochemistry were performed. RESULTS: Pigs on the hyperlipidemic diet had elevated mean (+/- SD) serum lipid levels (total cholesterol 5.05+/-1.45 mmol/L [Chol] and 5.03+/-2.41 mmol/L [High Chol+STZ] versus 2.09+/-0.23 mmol/L [controls]). Histopathological evaluation revealed an initial stage of coronary atherosclerosis. None of the STZ-treated pigs showed a sustained elevation of plasma glucose (mean glucose before STZ injection was 5.11+/-0.94 mmol/L and thereafter was 6.03+/-2.39 mmol/L) or a decline in pancreatic beta cells. CONCLUSIONS: The current data suggest that the domestic porcine model is not suitable to create severe CAD using an atherogenic diet in combination with STZ injections for experimental interventional vascular research. This may be due to different STZ sensitivities among species. However, hyperlipidemia induced early pathological lesions in coronary arteries resembling initial stages of atherosclerosis without severe luminal narrowing.

Association of cytokines with endothelium dependent flow mediated vasodilation (FMD) of systemic arteries in patients with non-ischemic cardiomyopathy.

BACKGROUND: Aim of this study was to elucidate the relation between localised inflammatory heart disease and endothelial dysfunction in the peripheral circulation, considering circulating cytokines as a potential link. METHODS: In 38 patients with non-ischemic heart disease, myocardial biopsies were examined for myocardial inflammation (immunohistology) and virus persistence (PCR). Cytokines (sIL-4, IFN-g, IFN-b, IFN-a, sIL-12p7, TNF-a) were measured by ELISA in venous serum. Endothelial function of the radial artery was examined by ultrasound, measuring diameter changes in response to reactive hyperemia (FMD), compared to glyceroltrinitrate (GTN-MD). Patients with EF < 35% were excluded. RESULTS: Age 44 +/- 14 years, 19 male, 19 female, EF 63.5[16]%. FMD 4.38 [4.82]%. 30 patients had myocardial inflammation (8 not), 23 virus persistence (15 not). FMD correlated significantly with sIL-12p7 (p = 0.024, r = -0.365), but not with other cytokines. sIL-12p7 levels were significantly higher in patients with severely impaired FMD (n = 17), compared with normal FMD (n = 21): 10.70 [10.72] vs. 4.33 [7.81] pg/ml (p = 0.002). Endothelium independent vasodilation (GTN-MD 23.67 [8.21]%) was not impaired. CONCLUSION: Endothelial dysfunction of peripheral arteries in patients with non-ischemic cardiomyopathy is associated with elevated serum concentrations of sIL-12p7, but not of other cytokines. Circulating sIL-12p7 may partly explain, that endothelial dysfunction is not restricted to the coronary circulation, but involves systemic arteries.

Correlation of epicardial and systemic flow-mediated vasodilation in patients with atypical angina but no evidence of atherosclerotic disease.

BACKGROUND: Atypical angina represents a diagnostic challenge and can be observed in the absence of significant coronary atherosclerosis. Endothelial dysfunction is a relevant marker of prognosis, considering cardiovascular events. The aim of the present study was to compare flow-mediated vasodilation (FMD) in systemic peripheral and epicardial coronary arteries. If noninvasive measurements of FMD in systemic arteries correlated with invasive measurements of coronary FMD, this may facilitate diagnostic approaches and determination of prognosis in patients with atypical angina in the future. Patients with atherosclerosis were excluded, because structural changes of coronary vessels may impair adequate comparison. METHODS: Endothelial function (ENF) of epicardial and systemic arteries was examined in 61 consecutive patients with atypical angina in whom significant atherosclerosis was excluded by coronary angiography. ENF of the epicardial arteries was examined during heart catheterization, measuring diameter changes of the proximal left anterior descending coronary artery (LAD) in response to reactive hyperemia, induced by locally administered adenosine via infusion catheter to the mid-segment of the LAD (coronary FMD [FMDc]). ENF of the radial artery was examined with high-resolution ultrasound, measuring peripheral FMD (FMDp) in response to reactive hyperemia induced by distal cuff occlusion. Endothelium-independent vasoreactivity to glycerol trinitrate was assessed. RESULTS: In patients with atypical angina in the absence of atherosclerosis, there was a significant correlation in ENF between coronary and systemic arteries (r=0.437; P=0.001). The underlying disease was myocardial inflammation (Inf) in 48 patients, in whom the mean (+/- SD) ENF of epicardial (FMDc-Inf 3.40+/-5.55%) and systemic (FMDp-Inf 3.69+/-2.93%) arteries was significantly impaired (P<0.001), compared with 13 control (Co) patients who had normal myocardial biopsies (FMDc-Co 14.51+/-8.62%; FMDp-Co 7.69+/-3.42%). FMD of coronary (r=-0.353; P=0.005) and systemic (r=-0.542; P<0.001) arteries correlated significantly with myocardial inflammation and endothelial activation. CONCLUSIONS: There was a significant correlation in FMD between coronary and systemic arteries in patients with atypical angina but without significant atherosclerosis. Inflammatory processes are associated with endothelial dysfunction of both vascular regions.

Prolonged application of clopidogrel reduces inflammation after percutaneous coronary intervention in the porcine model.

OBJECTIVE: We determined the effect of prolonged treatment with clopidogrel on C-reactive protein (CRP) concentrations and blood thrombogenicity after percutaneous transluminal coronary angioplasty followed by intracoronary brachytherapy in the porcine model. ANIMAL MODEL: All 48 pigs received antiplatelet therapy, including aspirin (325 mg, daily) and clopidogrel (300 mg, loading dose) 1 day before PCI, followed by a daily dose of clopidogrel (75 mg/day) in addition to aspirin. During PCI, one of two balloon-injured arteries was randomly assigned to receive immediate radiation treatment. Animals were sacrificed after 24 h, 1 month, and 3 months post-PCI. The pigs, which were sacrificed 3 months post-PCI, were divided into two groups. The first group received clopidogrel in addition to aspirin for 3 months, and the second group received clopidogrel in addition to aspirin for only 1 month after PCI and then aspirin alone. METHODS: Blood was taken from all pigs before intervention, immediately after intervention, and before sacrifice. Serum CRP was measured by enzyme-linked immunosorbent assay. To analyze the procoagulant effects of PCI on blood thrombogenicity, a one-stage clotting assay was performed. RESULTS: Clopidogrel treatment for 3 months reduced CRP levels more than did clopidogrel therapy for 1 month only at 3 months post-PCI (27.9+/-3.9 vs. 56.6+/-11.3 microg/ml; P=.019). Baseline CRP levels were found to be 50.4+/-4.8 microg/ml. Plasma clotting was not affected by prolonged clopidogrel therapy (322.8+/-59.3 s vs. 295.2+/-52.5 s; P=ns). CONCLUSIONS: Prolonged treatment with clopidogrel reduced CRP levels post-PCI.

Mechanisms of late lumen loss after antiproliferative percutaneous coronary intervention using beta-irradiation in a porcine model of restenosis.

BACKGROUND: The short-term results for the prevention of coronary restenosis after intravascular brachytherapy (IVBT) and use of drug-eluting stents (DESs) are excellent. The long-term results either lack or present with late complications (e.g., late thrombosis and late catch-up phenomenon leading to late restenosis even years after the initial procedure). Both IVBT and DESs mediate their potent antirestenotic effects via a cytostatic mechanism, but the cardiovascular pathology at late time points after the use of these antiproliferative therapies is incompletely understood. This study investigated the long-term effects of antiproliferative beta-irradiation in a clinically relevant porcine coronary model to address the pathophysiology of late coronary restenosis after antiproliferative vascular interventions. METHODS: We performed percutaneous transluminal coronary angioplasty (PTCA) in two major coronary arteries in 12 domestic crossbred pigs. One of the two balloon-injured segments was randomly assigned to receive immediate beta-irradiation (PTCA+IVBT group) using a noncentered delivery catheter (20 Gy; Novoste Beta-Cath System, Novoste, Norcross, GA, USA). The animals were sacrificed after 14 days (n=6) or 3 months (n=6). RESULTS: The luminal area in the PTCA+IVBT group decreased significantly 3 months after the intervention as compared with that in the PTCA group (PTCA 3.45+/-0.46 mm2 vs. PTCA+IVBT 1.22+/-0.26 mm2; P=.0017). This lumen loss was primarily due to shrinkage of the external elastic lamina area (negative arterial remodeling; PTCA 5.22+/-0.27 mm2 vs. PTCA+IVBT 3.42+/-0.45 mm2; P=.0064), which was accompanied by an increase in the adventitial area (PTCA 3.07+/-0.2 mm2 vs. PTCA+IVBT 5.41+/-0.5 mm2; P=.0049). CONCLUSIONS: The application of antiproliferative radiation in a porcine coronary model caused an early beneficial effect (reduction of intimal-medial lesion and luminal gain) that was followed by a late lumen loss primarily due to negative arterial remodeling. This mechanism may in part help us understand the pathophysiology of late adverse events occurring after IVBT.

Nf-kappab and AP-1 activation is associated with late lumen loss after porcine coronary angioplasty and antiproliferative beta-irradiation.

OBJECTIVE: Despite the success of antiproliferative therapies, restenosis remains a common problem after percutaneous transluminal coronary angioplasty (PTCA). Longer-term clinical results of brachytherapy (intracoronary radiation), the lack of long-term clinical results after implantation of drug eluting stents, and the occurrence of late thrombosis after both procedures leave room for skepticism. Neointimal proliferation is not substantially inhibited at late time points after brachytherapy, and late lumen loss with a "catch-up" proliferation can occur. We hypothesized that the transcription factors nuclear factor-{kappa}B (NF-kappaB) and activator protein-1 (AP-1) are involved in these processes. We addressed the role of these mediators in a porcine model of coronary restenosis. METHODS: Thirty-nine pigs underwent PTCA in two major coronary arteries. One of the two balloon-injured arteries was randomly assigned to receive immediate 20 Gy beta-irradiation (Brachy group) using a noncentered source train ((90)Sr/Y Beta-Cath, Novoste). Animals were sacrificed after 1 day, 14 days, or 28 days. Proliferating cells were labeled prior to euthanasia. RESULTS: At late time points, lumen area was significantly smaller and the inflammatory response was more pronounced in the Brachy group than in the PTCA group. These findings coincided with sustained activation of MMP-9 and transcription factors like NF-kappaB and AP-1. Initially, cell proliferation was reduced in the Brachy group; however, at late time points, differences between the two treatment groups were no longer significant. CONCLUSIONS: Brachytherapy initially inhibits cell proliferation; however, cellular and molecular inflammatory processes (e.g. activation of NF-kappaB) are enhanced within the arterial wall. This proinflammatory side effect may be responsible for the observed delayed proliferation and the resulting lumen loss.

Immunomodulation by interleukin-4 suppresses matrix metalloproteinases and improves cardiac function in murine myocarditis.

Immune response is critically involved in determining the course of viral myocarditis and immunomodulation. Different cytokines may have either deleterious or protective effects. Following acute Coxsackievirus B3 infection, intramyocardial inflammation is associated with altered myocardial matrix metalloproteinase (MMP) expression and left ventricular dysfunction. In this study, we evaluated the effect of exogenous interleukin-4 treatment on myocardial inflammation, MMPs and left ventricular function in Coxsackievirus B3-induced acute murine myocarditis. Eight-week-old inbred male BALB/c (H-2d) mice (The Jackson Laboratory, Bar Harbor, Maine, USA) were used. Myocardial inflammation was measured by immunohistochemical detection of CD3(+)-, CD8a(+)-T-lymphocytes, and CD11b+ macrophages. In situ hybridization was used to detect enteroviral genome in the myocardium. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was employed to detect cytokine and MMP mRNA. MMP activity was quantified by zymography analysis. Detection of myocytolysis was performed by Luxol fast blue staining. In the early acute phase, in comparison to infected mice without treatment, interleukin-4 administration (200 ng daily) reduced intramyocardial inflammation (CD3+ lymphocytes: 55.3+/-7.0 vs. 72.1+/-13.7 cells/mm2, P < 0.05; CD8a+ lymphocytes: 31.7+/-3.6 vs. 64.2+/-7.7 cells/mm2, P < 0.05; CD11b+ macrophages: 5.1+/-2.3 vs. 13.2+/-2.5 cells/mm2, P < 0.05). It also down-regulated interleukin-2 (IL) (1.7-fold, P < 0.001) but increased transforming growth factor-beta1 (TGF) (1.5-fold, P < 0.001) and IL-4 (1.4-fold, P < 0.001). IL-4 suppressed MMP-2/-3/-9 transcription and activity. These biochemical alterations were accompanied by a significant improvement of left ventricular function as assessed by Milar tip catheter (left ventricular endsystolic pressure, 1.3-fold, P < 0.01; dP/dt max, 1.5-fold, P < 0.01). Immunomodulation by exogenous IL-4 treatment may lead to an anti-inflammatory effect with the inhibition of Th1 cell phenotypic response, which may further mediate the down-regulation of MMPs. A significant suppression of MMPs may mainly contribute to an improvement of left ventricular dysfunction in acute murine CVB3-induced myocarditis.

Coronary vasospasm-induced acute diastolic dysfunction in a patient with Raynaud's phenomenon.

We present the case of a patient with severe dyspnea and Raynaud's phenomenon. We could clarify, using invasive techniques including left ventricular conductance catheterization and coronary ergonovine provocation, that isolated diastolic dysfunction induced by coronary vasospasm were responsible for the symptoms. Systolic function was not affected. Short-term infusions with the prostacyclin analogue iloprost, known to act as a disease-modifying agent in patients suffering from Raynaud's phenomenon, led to an improvement of cardiac function. Thus, episodes of dyspnea in patients with Raynaud's phenomenon might be also interpreted as a coronary ischemia equivalent, which may belong to a visceral form of Raynaud's phenomenon and which are sensitive to iloprost infusions.

Adventitial VEGF165 gene transfer prevents lumen loss through induction of positive arterial remodeling after PTCA in porcine coronary arteries.

Negative arterial remodeling still plays an important role in the pathogenesis of coronary restenosis even in the era of interventional stenting (e.g. arterial narrowing occurs proximal and distal of a stented segment). Previous studies suggest that increased angiogenesis and inhibited regression of injury-induced adventitial microvessels prevents negative remodeling. We have examined the effect of local vascular endothelial growth factor (VEGF(165)) gene transfer on adventitial microvessel angiogenesis/regression and arterial remodeling after coronary angioplasty. Twenty pigs underwent angioplasty, each one in two major coronary arteries, followed by plasmid liposome gene transfer with either VEGF(165) or control gene LacZ (50 microg DNA with 50 microg of Lipofectine) into the (peri)adventitial space using a needle injection catheter. Arteries were examined at days 1, 7, 14, and 28. Local delivery of VEGF(165) gene into the outer compartments of balloon-injured porcine coronary arteries reduced lumen area loss due to distinct positive remodeling (arterial enlargement). Prevention of adventitial microvessel regression, enhanced adventitial elastin accumulation, reduced adventitial myofibroblast numbers, and a pronounced adventitial inflammatory response considered as a part of arterial healing seem to be the main VEGF-mediated mechanisms indicating the therapeutic potential of VEGF for restenosis prevention.

An isoform shift in the cardiac adenine nucleotide translocase expression alters the kinetic properties of the carrier in dilated cardiomyopathy.

BACKGROUND: Impaired mitochondrial ADP/ATP transport and altered adenine nucleotide translocase (ANT) isoform expression characterized by enhanced ANT1 and decreased ANT2 expression have been implicated in the pathophysiology of dilated cardiomyopathy (DCM). It is still unknown whether restricted ANT function results from exogenous factors, or mutations in the ANT genes, or whether the imbalance in the isoform composition causes the reduced ADP/ATP transport. We performed DNA mutation screening of ANT genes and analyzed the kinetic properties of ANT protein isolated from DCM hearts and controls in a reconstituted system excluding natural environmental influences. RESULTS: A G1409T polymorphism in ANT2 leads to an exchange from Arg111 to Leu111 in healthy blood donors (n = 60) with allele frequencies of 76% and 24%. This polymorphism was neither associated with DCM (74%, 26%; n = 93) nor with altered myocardial ANT isoform expression or restricted ANT function (89%, 11%; n = 8). However, there was a remarkable reduction in the maximum transport activity (v(max)) of reconstituted ANT from DCM hearts with altered ANT isoform expression (498 +/- 113 micromol min(-1) g(-1) incorporated protein vs. 1112 +/- 178 micromol min(-1) g(-1) incorporated protein, p < 0.01). Moreover, the substrate affinity of DCM myocardial ANT to ATP was slightly reduced with an increased K(m) value of 104.3 +/- 2.4 microM vs. 90.4 +/- 2.9 microM in controls (p < 0.03). CONCLUSION: The altered isoform expression in DCM hearts entails changes in the kinetic properties of total ANT protein restricting ANT function and contributing to disturbed energy metabolism in DCM.

Abciximab therapy is associated with increased platelet activation and decreased heparin dosage in patients with acute myocardial infarction.

The inhibition of the glycoprotein (GP) IIb/IIIa receptor for reducing periprocedural ischemic events in patients undergoing coronary intervention is known to influence platelet reactivity. Suboptimal doses of GP IIb/IIIa antagonists have been suggested to be prothrombotic and proinflammatory. This study was performed to observe platelet activation markers, whole blood aggregation and the dosage of unfractionated heparin (UFH) in the presence or absence of the GP IIb/IIIa inhibitor abciximab. Patients with acute myocardial infarction undergoing percutaneous coronary intervention were treated with (n = 15) or without (n = 15) abciximab. Platelet activation markers were flow cytometrically measured before and after PCI. Whole blood platelet aggregation was tested by a platelet function assay. The patients with abciximab showed a significant increase in platelet activation markers (P-selectin: 7.12 +/- 0.36 AU vs 11.05 +/- 0.79 AU) and a lower requirement of UFH to prolong aPTT > 60 sec during the infusion. 12 hours after infusion P-selectin level decreased (7.20 +/- 0.58 AU), whereas whole blood aggregation was increasing again. After stopping abciximab, requirement of UFH to prolong aPTT increased in the treated group to a greater extent to a level similar to the untreated group even when most of the platelets were still inhibited. The increased platelet activation found at the end of abciximab treatment points to a procoaguable condition that should be carefully monitored and treated by adapting anticoagulation and antiplatelet drugs.