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To study the relationship between the quantitatively assessed coronary artery dimensions and the regional coronary flow reserve as measured by digital subtraction cineangiography, we investigated 17 coronary arteries with a single discrete proximal stenosis and 12 normal coronary arteries before and after intracoronary administration of papaverine. Coronary flow reserve was found to be curvilinearly related to minimal luminal cross-sectional area (r = .92, SEE = 0.73) and to percentage area stenosis (r = .92, SEE = 0.74). Normal coronary arteries had a coronary flow reserve of 5.0 (+/- 0.8 [SD]), which differed significantly from the coronary flow reserve of the coronary arteries with obstructive disease, in which values ranging from 0.5 to 3.9 were found. Coronary arteries with a percentage area stenosis between 50% and 70% and a minimal luminal cross-sectional area between 2 and 4.5 mm2 differed significantly (p = .001), with respect to the coronary flow reserve, from coronary arteries with a percentage area stenosis in excess of 70% and a minimal luminal cross-sectional area less than 2 mm2. With the use of hemodynamic equations that describe the pressure loss over a stenosis, a theoretical pressure-flow relationship can be inferred that characterizes the severity of the stenosis. Based on this theoretical pressure-flow relationship, coronary arteries that have a limited coronary flow reserve and critical stenosis (distal coronary perfusion pressure below 40 mm Hg at coronary flow of 3 ml/sec) can be identified with high sensitivity (83%) and specificity (82%). Thus, in coronary artery disease the consequent reduction in coronary flow reserve can be predicted with reasonable accuracy by quantitative assessment of coronary artery dimensions.

. Objective. Emotional distress has been related to clinical events in patients with coronary artery disease, but the influence of positive affect (i.e. mood states such as activity, joy and cheerfulness) has received little attention. Therefore, we wanted to investigate the role of positive affect on clinical outcome after percutaneous coronary intervention (PCI) with stent implantation in these patients. Design. Prospective follow‐up study. At baseline, patients from the Rapamycin‐Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) registry completed measures of positive affect, depression and anxiety post‐PCI. Patients with reduced positive affect scored 1 SD below the mean score. Setting. University Hospital; Thoraxcenter of the Department of Cardiology. Subjects. 874 patients (72% men; 62.2 ± 10.9 years) from the RESEARCH registry. Main outcome measure. Death or myocardial infarction (MI) 2 years post‐PCI. Results. At follow‐up, there were 52 clinical events (deaths n = 27, MIs n = 25). Reduced positive affect and depression/anxiety were associated with poor prognosis, but reduced positive affect was the only independent predictor of events. The incidence of death/MI in adequate versus reduced positive affect patients was 4% (29/663) vs. 11% (23/211); HR = 2.55 (95% CI 1.46–4.34, P = 0.001), adjusting for clinical variables. Reduced positive affect and diabetes were independent prognostic factors, and patients with one (HR = 2.84, 95% CI 1.58–5.10) or both (HR = 5.61, 95% CI 2.25–13.99) of these factors had a higher risk when compared with nondiabetic patients with adequate positive affect, P ≤ 0.003. Conclusions. Reduced positive affect independently predicted death/MI following stent implantation, and improved risk stratification above and beyond diabetes.

The plasma membrane of airway smooth muscle contains a high density of K+ channels of various types that mainly regulate membrane potential. To examine whether these K+ channels are involved in bronchodilating mechanisms in human airways, relaxation concentration-response studies to isoproterenol, theophylline, and a K(+)-channel opener, lemakalim (BRL 38227), were obtained in the presence or absence of charybdotoxin (ChTX) (10 or 100 nM), an inhibitor of large conductance Ca(2+)-activated K+ channels (KCa) in smooth muscle. The effects of other potassium channel blockers, apamin (0.1 microM, a small-conductance KCa blocker) and BRL 31660 (10 microM, an ATP-sensitive K(+)-channel blocker) on isoproterenol-induced bronchodilation were also examined. All relaxation studies were performed on spontaneous tone and in the presence of 1 microM indomethacin. ChTX produced a dose-dependent significant rightward shift in the isoproterenol relaxation response curves without changing maximum relaxation; geometric mean values of EC50 were 4.6 nM without and 19 nM with 10 nM ChTX (n = 7, p less than 0.005), and 3.4 nM without and 41 nM with 100 nM ChTX (n = 4, p less than 0.05), respectively. The theophylline relaxation responses were inhibited to a lesser extent by ChTX (10 nM) (ED50 of 32 microM without and 71 microM with ChTX, n = 7, p less than 0.05), whereas lemakalim-induced relaxation response was not affected. Other K(+)-channel blockers, apamin and BRL31660, failed to affect isoproterenol-induced bronchodilation. These results suggest that ChTX-sensitive K+ channels are involved in bronchodilation induced by beta-agonists and theophylline in human airways.

A novel approach for the treatment of acute complications and the prevention of restenosis after percutaneous transluminal angioplasty may be the placement of endovascular prostheses (stents). Stents constructed of metal have proven to be thrombogenic, and although they show a tendency to reduce restenosis, they do not prevent it. Pursuant to the search for stents with improved material and surface characteristics, we report in this paper the histological results obtained with a synthetic polymer (polyethylene terephthalate) stent after placement in porcine peripheral arteries. Eight stents were placed at a preselected site and resulted in a 87.5% angiographic patency rate at four weeks' follow-up examination. The neointima measured 114 ± 38 μm (mean ± SEM) on top of the fibers and 246 ± 44 μm between the fibers. Medial impression by the stent measured 27% ± 5%. The neointima consisted mainly of smooth muscle cells. A variable inflammatory reaction and foreign body response to the polymer was observed in all vessels. The present study shows the feasibility of the arterial implantation of polymer stents, in that they result in good intermediate-term arterial patency and limited neointimal hyperplasia. The observed inflammatory reaction, if prolonged, may limit the use of this polymer stent.

Incidence, associated risk factors and impact on mortality of infections after bypass surgery (CABG) and stenting (PCI) for multivessel coronary disease (MVD) have never been reported in a large randomised trial. The aim of the present study was to evaluate, in patients with MVD, the prevalence of major infections after PCI and CABG and to assess their impact on mortality.The SYNTAX trial randomised 1,800 MVD patients to either CABG or PCI. Patients were followed up to five years. The primary endpoint of this post hoc analysis was the occurrence of major infection. At five years of follow-up, the primary endpoint had occurred in 142 (15.8%) patients in the CABG arm and 44 (4.9%) patients in the PCI arm (≤60 days HR - 7.9, 95% CI: 4.7 to 13.1; p<0.001) (>60 days - HR 0.79, 95% CI: 0.44 to 1.44; p=0.45). Major infections were independently associated with a higher risk of all-cause mortality at five years (adjusted HR 2.6, 95% CI: 1.8 to 3.8, p<0.001).CABG is associated with a higher incidence of post-procedure major infections compared to PCI. Major infections are independently associated with all-cause mortality.