Biomedical subjects

James Forrester

Publications and source records attributed to James Forrester.

5 recordsLinked to original sources

PubMed2007

Stent fracture associated with drug-eluting stents: clinical characteristics and implications.

OBJECTIVE: To evaluate the clinical characteristics and implications of stent fracture in drug-eluting stents. BACKGROUND: Approximately 2.5 million drug-eluting stents are implanted every year worldwide. In 10 randomized controlled trials involving 2,602 patients, no incidence of stent fracture was recognized or reported. METHODS: From April 2003 to December 2005, 2,728 patients underwent drug-eluting stenting. The angiograms of all 530 patients who underwent repeat angiography were analyzed to identify the presence of stent fracture. We then documented the incidence of adverse events associated with drug-eluting stent fracture and systematically analyzed the clinical, procedural, and structural factors, which might predispose to stent fracture. RESULTS: Stent fracture was identified in 10 patients. None of these fractures were detectable at the time of stent placement. The median time interval from stent implantation to detection of fracture at repeat angiography was 226 days (range, 7-620 days). Adverse clinical outcomes associated with stent fracture occurred in 7 patients (6 patients had binary restenosis and 1 patient had stent thrombosis), all necessitating repeat intervention. Analysis of potential predisposing clinical, procedural, and structural factors revealed that 4 patients had excessive tortuosity in the proximal segment, and overlapping stents were used in 5 cases. All fractures occurred in sirolimus-eluting stents. CONCLUSIONS: Stent fracture may represent a new potential mechanism of restenosis and stent thrombosis in drug-eluting stents. Predisposing clinical and procedural factors may be vessel tortuosity and use of overlapping stents. The most important predisposing factor, however, may be stent structure, since all fractures occurred in sirolimus-eluting stents.

Adult↗

PubMed2006

The effect of granulocyte colony stimulating factor on regional and global myocardial function in the porcine infarct model.

BACKGROUND: Stem cell therapy has been shown to attenuate the reduction of left ventricular function following myocardial infarction. Most studies have utilized either a direct injection or intra-coronary infusion of cells, but cytokine mobilization of stem cells in the murine model of acute myocardial infarction has been reported to induce similar improvement in cardiac function. METHODS: An antero-apical infarction was induced in swine by balloon occlusion, followed by the daily administration of granulocyte colony stimulating factor (G-CSF) or placebo for 5 days. We used left ventricular angiograms and 2D echocardiograms to assess global function, and 3D echocardiograms to assess regional function prior to infarction, immediately following infarction, and at 8 weeks. Histologic evaluation was performed after sacrifice at 8 weeks. RESULTS: There was no significant difference in early or late post-infarction left ventricular ejection fraction or in myocardial histology between the two groups. Following G-CSF therapy, however, 3D echocardiography demonstrated that the regional ejection fractions of the infarcted segments showed a 50.3% improvement in the G-CSF pigs compared to a 7.4% deterioration in the untreated pigs (p=0.005). CONCLUSIONS: Global left ventricular ejection fraction remained unchanged, and there is no histologic evidence for infarct attenuation following G-CSF infusion in the porcine infarct-reperfusion model. There was recovery of regional function in the infarcted segment in the G-CSF pigs. These data suggest that bone marrow mobilization in larger species has limited potential as a therapy designed to replace infarcted myocardium or to improve overall cardiac function, although further studies are needed to examine regional effect in the infarct area.

Animals↗

PubMed2006

Comparison of coronary artery bypass surgery with percutaneous coronary intervention with drug-eluting stents for unprotected left main coronary artery disease.

OBJECTIVES: This study evaluated the clinical outcomes of consecutive, selected patients treated with coronary artery bypass graft (CABG) surgery or percutaneous coronary intervention (PCI) with drug-eluting stents (DES) for unprotected left main coronary artery (ULMCA) disease. BACKGROUND: Although recent data suggest that PCI with DES provides better clinical outcomes compared to bare-metal stenting for ULMCA disease, there is a paucity of data comparing PCI with DES to CABG. METHODS: Since April 2003, when DES first became available at our institution, 123 patients underwent CABG, and 50 patients underwent PCI with DES for ULMCA disease. RESULTS: High-risk patients (Parsonnet score >15) comprised 46% of the CABG group and 64% of the PCI group (p = 0.04). The 30-day major adverse cardiac and cerebrovascular event (MACCE) rate for CABG and PCI was 17% and 2% (p < 0.01), respectively. The mean follow-up was 6.7 +/- 6.2 months in the CABG group and 5.6 +/- 3.9 months in the PCI group (p = 0.26). The estimated MACCE-free survival at six months and one year was 83% and 75% in the CABG group versus 89% and 83% in the PCI group (p = 0.20). By multivariable Cox regression, Parsonnet score, diabetes, and CABG were independent predictors of MACCE. CONCLUSIONS: Despite a higher percentage of high-risk patients, PCI with DES for ULMCA disease was not associated with an increase in immediate or medium-term complications compared with CABG. Our data suggest that a randomized comparison between the two revascularization strategies for ULMCA may be warranted.

Aged↗

PubMed2006

Coronary sinus is dilated and outwardly displaced in patients with mitral regurgitation: quantitative angiographic analysis.

OBJECTIVES: Our aim was to define the anatomy of the coronary sinus (CS) by venography. These measurements are essential in the selection of physical characteristics of percutaneous annuloplasty devices for mitral regurgitation (MR). BACKGROUND: Clinical trials of percutaneous annuloplasty of the CS for MR are now underway. Although the CS is in close proximity to the mitral annulus, there is as yet no published quantitative data defining the magnitude of change in CS dimensions in MR, and how these changes might reflect the magnitude of MR. METHODS: We studied 57 patients (27 patients with MR and 30 patients with no MR) who were referred for cardiac resynchronization therapy and underwent CS venography. Echocardiography was used to assess the degree of MR, cardiac dimensions, and right heart filling pressures. The diameter of the ostial and proximal CS and perimeter of the CS-great cardiac vein (GCV) were assessed by quantitative coronary analysis. RESULTS: Patients with MR had a larger ostial CS diameter (19.4+/-3.9 mm vs. 16.9+/-4.6 mm, P=0.02) and proximal CS diameter (8.2+/-1.7 mm vs. 7.4+/-2.3 mm, P=0.05) and larger CS-GCV perimeter (104.4+/-15.6 mm vs. 86.5+/-15.3 mm, P=0.005) compared with patients with no MR. The CS-GCV perimeter is positively correlated to the severity of MR (P=0.02) and pulmonary artery pressure (r=0.32, P<0.05). CONCLUSIONS: Patients with MR have a dilated and outward displacement of the CS. The CS-GCV perimeter is positively correlated with the degree of MR and pulmonary artery pressure.

Analysis of Variance↗

PubMed2003

The SoS trial.

Explore the source record for details and available documents.

Angioplasty, Balloon, Coronary↗