Robert J. Chisholm

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OBJECTIVES The aim of this study was: 1) to evaluate the acute and late outcomes of a transcatheter aortic valve implantation (TAVI) program including both the transfemoral (TF) and transapical (TA) approaches; and 2) to determine the results of TAVI in patients deemed inoperable because of either porcelain aorta or frailty. BACKGROUND Very few data exist(More)
Remodeling of the vessel wall after balloon angioplasty injury is incompletely understood, and in particular, the role of extracellular matrix synthesis in restenosis has received little attention. The objective of the present study was to determine the sequence of changes in collagen, elastin, and proteoglycan synthesis and content after balloon injury and(More)
BACKGROUND Transradial percutaneous coronary intervention (PCI) results in fewer vascular complications, earlier ambulation, and improved patient comfort. Limited data exist for radial access in acute myocardial infarction, where reperfusion must occur quickly. METHODS In a multicenter pilot trial, 50 patients with myocardial infarction requiring either(More)
Extracellular matrix formation is the major component of the restenosis lesion that develops after balloon angioplasty. Although ex vivo studies have shown that the synthesis of collagen is stimulated early after balloon angioplasty, there is a delay in accumulation in the vessel wall. The objectives of this study were to assess collagen turnover and its(More)
OBJECTIVES This study sought to evaluate the long-term outcomes after transcatheter aortic valve implantation (TAVI) in the Multicenter Canadian Experience study, with special focus on the causes and predictors of late mortality and valve durability. BACKGROUND Very few data exist on the long-term outcomes associated with TAVI. METHODS This was a(More)
OBJECTIVES Our objective was to analyze the impact of arterial access site, sheath size, timing of sheath removal, and use of access site closure devices on high-risk patients with acute coronary syndromes (ACS). BACKGROUND In the SYNERGY trial, 9,978 patients with ACS were randomly assigned to receive enoxaparin or unfractionated heparin. METHODS This(More)
Over the years, permissible radiation exposure of operators working with x-ray equipment has become progressively reduced. The number of cardiac catheterizations and related interventional procedures has increased and the procedures have become more prolonged. The patient receives relatively infrequent primary radiation while the operator receives frequent(More)
BACKGROUND The fibrinolytic system is intimately involved in several processes that contribute to restenosis, including clot dissolution, cell migration, and tissue remodeling. However, the role of the individual activators (urokinase [uPA] and tissue plasminogen [tPA] activators) and inhibitors (plasminogen activator inhibitor [PAI-1]) of the fibrinolytic(More)
The burden of pregnancy in patients with severe mitral stenosis continues to present a therapeutic challenge. We present two such cases successfully treated with balloon valvuloplasty using the Inoue balloon. The unique features of this balloon may render it the technique of choice for selected pregnant patients with severe mitral stenosis.
BACKGROUND The safety and efficacy of a radial approach for percutaneous coronary intervention (PCI) in octogenarians is not well established. METHODS To evaluate the benefits of a radial approach for preventing vascular complications after PCI, clinical, procedural, and outcome data were prospectively collected and compared for 228 octogenarians(More)