Trans-Myocardial Blood Interleukin-6 Levels Relate to Intracoronary Imaging-Defined Features of Plaque Vulnerability and Predict Procedure-Induced Myocardial Infarction.

BACKGROUND: Intravascular imaging has defined various vulnerable plaque (VP) phenotypes that predict future clinical events. Atherosclerosis is an inflammatory process and inflammation, measured by systemic biomarkers can also predict events and anti-inflammatory therapy is beneficial. We were interested to assess the relationship between plaque phenotypes and key inflammatory biomarkers, measured close to the coronary. METHODS: Ninety-two patients scheduled for elective percutaneous coronary intervention (PCI) underwent virtual histology intravascular ultrasound, optical coherence tomography, pressure wire and blood sampling from the guide catheter (GC), coronary sinus (CS) to determine trans-myocardial gradient (TMG = CS-GC) and from peripheral blood. Procedure related troponin release was assessed at 6-hours post-PCI from peripheral venous blood. Biomarker data were analysed and compared with coronary data. RESULTS: Interleukin (IL)-6 was associated with increased levels of tumour necrosis factor (TNF)-α and C-reactive protein (CRP) and the pre-PCI IL-6 TMG correlated with plaque features of vulnerability: plaque burden - PB (r = 0.253, p = 0.04) and minimal lumen area - MLA (r = -0.438, p = 0.007), although no relationship existed for thin-capped fibroatheroma defined by either imaging modality. Peripheral IL-6 levels had no correlation with post PCI troponin, although the pre-PCI IL-6 TMG was related (r = 0.334, p = 0.006), as was PB (r = 0.27, p = 0.029). CONCLUSION: IL-6 TMG pre-PCI correlates with plaque burden and MLA that have been shown to predict future clinical events and is correlated with post-PCI troponin release. These associations were not apparent from peripheral blood and suggest that local coronary biomarker signatures may help further define vulnerability and risk.

Cost-effectiveness of initial stress cardiovascular MR, stress SPECT or stress echocardiography as a gate-keeper test, compared with upfront invasive coronary angiography in the investigation and management of patients with stable chest pain: mid-term outcomes from the CECaT randomised controlled trial.

OBJECTIVES: To compare outcomes and cost-effectiveness of various initial imaging strategies in the management of stable chest pain in a long-term prospective randomised trial. SETTING: Regional cardiothoracic referral centre in the east of England. PARTICIPANTS: 898 patients (69% man) entered the study with 869 alive at 2 years of follow-up. Patients were included if they presented for assessment of stable chest pain with a positive exercise test and no prior history of ischaemic heart disease. Exclusion criteria were recent infarction, unstable symptoms or any contraindication to stress MRI. PRIMARY OUTCOME MEASURES: The primary outcomes of this follow-up study were survival up to a minimum of 2 years post-treatment, quality-adjusted survival and cost-utility of each strategy. RESULTS: 898 patients were randomised. Compared with angiography, mortality was marginally higher in the groups randomised to cardiac MR (HR 2.6, 95% CI 1.1 to 6.2), but similar in the single photon emission CT-methoxyisobutylisonitrile (SPECT-MIBI; HR 1.0, 95% CI 0.4 to 2.9) and ECHO groups (HR 1.6, 95% CI 0.6 to 4.0). Although SPECT-MIBI was marginally superior to other non-invasive tests there were no other significant differences between the groups in mortality, quality-adjusted survival or costs. CONCLUSIONS: Non-invasive cardiac imaging can be used safely as the initial diagnostic test to diagnose coronary artery disease without adverse effects on patient outcomes or increased costs, relative to angiography. These results should be interpreted in the context of recent advances in imaging technology. TRIAL REGISTRATION: ISRCTN 47108462, UKCRN 3696.

Flecainide overdose--support using an intra-aortic balloon pump.

BACKGROUND: Flecainide is an antiarrhythmic agent which is being used increasingly for the management of super-ventricular arrhythmias. Overdose with flecainide is frequently fatal with mortality reported as high as 22% due to arrhythmias, myocardial depression and conduction defects leading to electro-mechanical dissociation and asytole. Supportive measures are often required during the case and previously have included inotropes, extracorporeal membrane oxygenation and cardiopulmonary bypass. CASE PRESENTATION: A 47 year old lady presented to the emergency department with a four hour history of severe central chest pain. Her ECG showed atrial fibrillation and broad QRS complexes with a sine wave appearance. She had a past history of paroxysmal atrial fibrillation and significant psychiatric history. Following thrombolysis for a presumed myocardial infarction she developed cardiogenic shock with severely impaired left ventricular function. An intra-aortic balloon pump was inserted and coronary angiography demonstrated normal coronary arteries. With inotropic support she improved over 48 hours, with both her QRS duration and left ventricular function returning to normal. Biochemical testing following her discharge demonstrated significantly elevated levels of flecainide. CONCLUSION: The use of an intra-aortic balloon pump is a useful supportive measure during the acute phase of flecainide overdose associated with severe myocardial depression.