Diese Präsentation wurde erfolgreich gemeldet.
Wir verwenden Ihre LinkedIn Profilangaben und Informationen zu Ihren Aktivitäten, um Anzeigen zu personalisieren und Ihnen relevantere Inhalte anzuzeigen. Sie können Ihre Anzeigeneinstellungen jederzeit ändern.

131 the evolution of coronary atherosclerosis

348 Aufrufe

Veröffentlicht am

SHAPE Society

Veröffentlicht in: Gesundheit & Medizin
  • Login to see the comments

  • Gehören Sie zu den Ersten, denen das gefällt!

131 the evolution of coronary atherosclerosis

  1. 1. The “Evolution” of Coronary Atherosclerosis (Libby. Circulation 2001;104: 365) Normal Artery Lesion Initiation Fibro-fatty Stage Vulnerable Plaque Plaque Rupture Fibrous, Calcified Plaque Endothelial Erosion Progression over time (yrs):
  2. 2. Can the Trajectories of the Natural Histories of Coronary Atherosclerosis Be Identified Prior to Adverse Coronary Events? Opportunities for Intervention Snapshot at time of angina or MI Snapshot to identify vulnerability Snapshot to identify likelihood to develop vulnerability or progression Quiescent, Stable plaque no symptoms Fibrotic/ Scarred plaque angina Vulnerable, Ruptured Plaque MI, sudden death ?
  3. 3. The Effect of Physiologic Shear Stress on Endothelial Structure and Function Physiologic shear stress (~15-50 dynes/cm2 ) is vasculoprotective: (Malek, et al. JAMA 1999; 282:2035) • Enhances endothelial quiescence - decreases proliferation • Enhances vasodilation • Enhances anti-oxidant status • Enhances anti-coagulant and anti-thrombotic status
  4. 4. The Detrimental Effect of Low Shear Stress on Endothelial Structure and Function Low shear stresses and disturbed local flow (< ~ 6 dynes/cm2 ) are atherogenic: (Malek, et al. JAMA 1999; 282:2035) • Cell proliferation, migration • Expression of vascular adhesion molecules, cytokines, mitogens • Monocyte recruitment and activation • Procoagulant and prothrombotic state • Local oxidation Promotes:
  5. 5. Original angiogram of a portion of an artery studied Composite reconstruction of portion of the arterial segment, consisting of outer arterial wall, plaque, and lumen: Isolated view of reconstructed outer arterial wall: Isolated view of reconstructed lumen: Isolated view of reconstructed atherosclerotic plaque: Example of 3-D Reconstruction of Arterial Segment (Stone, et al. Circulation 2003;108:438)
  6. 6. Coronary Endothelial Shear Stress w y u WSS ∂ ∂ µ= dynes/cm2 [Artery is displayed as if it were cut and opened longitudinally, as a pathologist would view it.] (Feldman and Stone. Curr Opin Cardiol 2000; 15: 430)
  7. 7. Changes in Native Arteries Change in Plaque Thickness (mm) Change in EEM Radius (mm) Change in Lumen Radius (mm) Change in ESS (dynes/cm2 ) Regions of baseline low ESS:: • increase in plaque thickness • enlargement of EEM (outward remodeling) Regions of baseline physiologic ESS: • little change in any variable Regions of baseline increased ESS: • increase in lumen radius • increase in EEM radius • decrease in ESS (outward remodeling) ESS at Baseline and Vascular Outcomes 6 mo later: p<0.001 p<0.001p=0.03 (Stone, et al. Circulation 2003;108:438)
  8. 8. Prediction of Areas of Minor Obstruction Which Are Actively Progressing Identification of Limits of Outward Remodeling and Initiation of Lumen Narrowing In-vivo (Feldman, et al 2003, submitted) (Confirmation of Glagov Hypothesis)
  9. 9. New Era of “Preventive” Vascular Approaches: Identification of High-Risk, Minor Obstructions and Application of Focused Interventions To Avert Adverse Coronary Events Lesion at time of clinical event Identification of “vulnerability” Minor lesion likely to become vulnerable or progress Quiescent, Stable plaque no symptoms Fibrotic/ Scarred plaque angina Vulnerable, Ruptured Plaque MI, sudden death X X X
  10. 10. New Era of “Preventive” Vascular Approaches: Identification of High-Risk, Minor Obstructions and Application of Focused Interventions To Avert Adverse Coronary Events Lesion at time of clinical event Identification of “vulnerability” Minor lesion likely to become vulnerable or progress Quiescent, Stable plaque no symptoms Fibrotic/ Scarred plaque angina Vulnerable, Ruptured Plaque MI, sudden death X X X

×