Biomedical subjects

B O'Shaughnessy

Publications and source records attributed to B O'Shaughnessy.

16 recordsLinked to original sources

PubMed2000

Coronary angioplasty in New Zealand 1995-1998: a report from the National Coronary Angioplasty Registry.

AIMS: To report coronary angioplasty data collected by the New Zealand Coronary Angioplasty Registry from 1995-1998. METHOD: Information on all patients undergoing attempted coronary angioplasty in eight New Zealand institutions was recorded on datasheets at the time of, or soon after, the procedure. These were forwarded to the registry at Green Lane Hospital. RESULTS: Over the four-year period, 8395 angioplasty procedures were performed by 26 cardiologists in eight coronary interventional facilities, with a procedural success rate of 94%. Procedural numbers grew steadily, with 55% more coronary angioplasties performed in 1998 than in 1995 (p = 0.02). The New Zealand national angioplasty rate, which rose from 459/million population in 1995 to 684/million in 1998, remains lower than that of Australia and Western European countries. Excluding those that underwent angioplasty for acute myocardial infarction, the number of peri-procedural deaths was similar, with six in 1995 and four in 1998 (p = 0.30), and the requirement for emergency bypass surgery fell from 22 cases in 1995 to three in 1998 (p < 0.001). The use of stents increased dramatically, with 85% of patients receiving a stent in 1998, compared with 23% in 1995 (370% increase, p < 0.001). This was associated with a reduction in the number of patients requiring repeat percutaneous interventions for restenosis (10.7% in 1995 to 6.4% in 1998, p < 0.001). CONCLUSION: There has been a steady growth in the numbers of patients with coronary artery disease treated by coronary angioplasty, and in the number treated by intracoronary stents from 1995 to 1998. The need for urgent coronary bypass surgery has fallen. Continued submission of complete and accurate data to the coronary angioplasty registry is vital for ongoing audit.

Adult↗

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