Biomedical subjects

B O'Shaughnessy

Publications and source records attributed to B O'Shaughnessy.

15 recordsLinked to original sources

PubMed2000

Interfacial reactions: mixed order kinetics and segregation effects

We study A-B reaction kinetics at a fixed interface separating A and B bulks. Initially, the number of reactions R(t) approximately tn(infinity)(A)n(infinity)(B) is second order in the far-field densities n(infinity)(A), n(infinity)(B). First order kinetics, governed by diffusion from the dilute bulk, onset at long times: R(t) approximately x(t)n(infinity)(A), where x(t) approximately t(1/z) is the rms molecular displacement. Below a critical dimension, d 0) leads to anomalous decay of interfacial densities. Numerical simulations for z = 2 support the theory.

Journal Article↗

PubMed1999

Preliminary experience with the V-flex plus coronary stent: immediate and one-month clinical outcome.

Procedural and 1-month outcome data following implantation of the V-Flex Plus stent in our first 54 consecutive patients (35 male; mean age, 62 years) are described. Sixty-four stents were implanted for 60 mainly complex lesions; 48% were left anterior descending; 20%, circumflex; 27%, right coronary artery; and 5%, saphenous vein graft. The Indication for stenting was elective in half of the patients and for a suboptimal result or as a bailout procedure in the other half. The stents were deployed at a mean of 12 atm (range, 6-18) and postdilatated to a mean of 15 atm (range, 8-20). Pre- and postdilatation balloon sizes were 2.96 +/- 0.57 mm and 3.16 +/- 0.34 mm, respectively. The procedural success rate was 98%. There were no deaths or Q-wave myocardial infarctions. One patient suffered a non-Q-wave myocardial infarction and another developed a femoral false aneurysm. At 1-month follow-up, there were no additional events, in particular no revascularization procedures. Eighty-nine percent of patients were free of angina. Implantation of the V-Flex Plus stent is safe and effective with an excellent early success rate comparable to that of published randomized trials and registries of carefully selected patients.

Adult↗

PubMed1998

Introduction of the Multilink stent into routine angioplasty practice: early angiographic and clinical outcome.

To assess the early outcome of implantation of the Multilink stent in everyday angioplasty practice, we prospectively collected procedural and 1-mo follow-up data on the first 126 patients (93 male, mean age 61+/-9 yr) in 3 centers. One hundred and seventy-four stents were implanted for 134 lesions: left anterior descending artery in 46%, circumflex in 20%, right coronary artery in 31%, and protected left main in 3%. The indication was elective in 56%, a suboptimal result in 43%, and bailout in 1%. Stents were deployed at 10.8+/-1.9 atmospheres and postdilated to 15.7+/-2.4 atmospheres. There were 115 patients who received ticlopidine and aspirin, 10 received aspirin alone, and 1 received warfarin and aspirin following the procedure. The reference diameter increased from 3.02+/-0.44 mm pre- to 3.13+/-0.43 mm postprocedure, with the minimal luminal diameter increasing from 0.82+/-0.47 to 2.86+/-0.45 mm (diameter stenosis 73% pre- and 9% postprocedure). The procedural success rate was 93.7%. There were no deaths, 1 (0.8%) Q- and 5 (4.0%) non-Q-wave myocardial infarctions, 3 (2.4%) emergency bypass operations, and 1 (0.8%) repeat angioplasty during the hospital admission (median stay, 1 day). There were 2 (1.6%) cases of subacute stent thrombosis. At 1-mo follow-up there were no additional events, with 88% of patients remaining free of angina. Implantation of the Multilink stent is safe and effective in everyday angioplasty practice, with a complication rate comparable to those of published trials of carefully selected patients.

Adult↗

PubMed1996