This experimental model of commotio cordis closely resembles the clinical profile of this catastrophic event. Whether ventricular fibrillation occurred depended on the precise timing of the impact. Safety baseballs, as compared with regulation balls, may reduce the risk of commotio cordis.

We show that the interplay between geometric criticality and dynamical fluctuations leads to a novel universality class of the contact process on a randomly diluted lattice. The nonequilibrium phase transition across the percolation threshold of the lattice is characterized by unconventional activated (exponential) dynamical scaling and strong Griffiths effects. We calculate the critical behavior in two and three space dimensions, and we also relate our results to the recently found infinite-randomness fixed point in the disordered one-dimensional contact process.

No abstract

SUMMARYDrug-eluting stent (DES) implantation may be associated with endothelial dysfunction. However, changes in long-term endothelial function based on the type of DES remain largely unknown. We assessed coronary endothelial function after DES implantation compared to bare-metal stents (BMS) and determined the differences according to DES type.Patients who had single BMS or DES implantation in the left anterior descending artery and showed no restenosis in follow-up angiography at 6 to 9 months were assigned to the BMS group (5 patients) or DES group (9 sirolimus-eluting stents, SES, and 8 paclitaxel-eluting stents, PES). Endothelium-dependent vasomotion, after intracoronary infusion of acetylcholine, was determined by quantitative coronary angiography. Also, endothelium-independent vasomotion was assessed after nitrate infusion.In the distal and far distal segments, the SES (SES versus BMS, distal: -27.6 ± 16.3% versus -0.6 ± 1.6%; P = 0.01, far distal: -24.8 ± 13.2% versus -0.9 ± 1.3%; P = 0.02) and PES groups (PES versus BMS, distal: -25.4 ± 17.1% versus -0.6 ± 1.6%; P = 0.01, far distal: -26.6 ± 15.9% versus -0.9 ± 1.3%; P = 0.01) had similar patterns showing significant vasoconstriction compared with the BMS group. In addition, the DES group showed a significant reduction of diameter in distal (SES: P = 0.001, PES: P = 0.04) and far distal segments (SES: P = 0.002, PES: P = 0.001) compared with proximal and near proximal segments. However, the BMS group did not demonstrate significantly different vasomotion between proximal and distal segments. Vasodilatation by nitrate infusion was preserved in all subjects.SES or PES implantation could be associated with the similar pattern of endothelial dysfunction identified predominantly in the long distal portion of the treated vessel. (Int Heart J 2007; 48: 553-567)