Diagnostic accuracy of optical coherence tomography and integrated backscatter intravascular ultrasound images for tissue characterization of human coronary plaques.

Objectives: The purpose of the present study was to validate the diagnostic accuracy of optical coherence tomography (OCT), integrated backscatter intravascular ultrasound (IB-IVUS), and conventional intravascular ultrasound (C-IVUS) for tissue characterization of coronary plaques and to evaluate the advantages and limitations of each of these modalities.

Background: The diagnostic accuracy of OCT for characterizing tissue types is well established. However, comparisons among OCT, C-IVUS, and IB-IVUS have not been done.

Magnetic resonance assessment of myocardial perfusion via catheter-based ventricle-coronary vein bypass in porcine myocardial infarction model.

Objective: The goal of this study was to investigate the efficacy of VPASS with physiological measurements, magnetic resonance imaging (MRI), and histology in a porcine model of myocardial infarction.

Background: A catheter-based ventricle-to-coronary vein bypass (VPASS) has been proposed as a potential treatment strategy for refractory coronary artery disease patients.

Methods: In an acute setting, the VPASS implant was deployed percutaneously in three swine.

Intravascular optical coherence tomography: cellular imaging.

The vast majority of acute coronary events are attributed to rupture or erosion of high-risk or vulnerable plaques. Novel imaging techniques are being actively sought that can detect quiescent vulnerable features within coronary plaque and thereby identify populations at risk, monitor plaque progression, and target therapy appropriately. Optical coherence tomography is an intravascular imaging modality capable of detecting and characterizing coronary plaque in vivo.

Catheter-based ventricle-coronary vein bypass.

The goal of this study was to investigate the feasibility of a catheter-based ventricle-to-coronary vein bypass (VPASS) in order to achieve retrograde myocardial perfusion by a conduit (VSTENT) from the left ventricle (LV) to the anterior interventricular vein (AIV). Percutaneous coronary venous arterialization has been proposed as a potential treatment strategy for otherwise untreatable coronary artery disease. In an acute setting, the VSTENT implant was deployed percutaneously using the VPASS procedure in five swine.

Focal and multi-focal plaque macrophage distributions in patients with acute and stable presentations of coronary artery disease.

Objectives: This study was designed to utilize optical coherence tomography (OCT) images of coronary atherosclerotic plaque macrophages to investigate the relationship between macrophage distributions and clinical syndrome.

Background: The relative significance of focal macrophage infiltration and generalized coronary inflammation for predicting acute coronary events is a currently a source of considerable controversy in cardiology. Lack of a high-resolution cross-sectional imaging modality has limited macrophage evaluation in vivo.

Coronary in-stent restenosis following beta brachytherapy: a histopathological examination.

Two cases of in-stent restenosis of a coronary artery bypass vein graft following beta (beta) brachytheraphy are presented. Previously unreported histopathology of directed atherectomy specimens of such restenotic lesions and a discussion of their proposed significance form the basis of this report.

The porcine coronary model of in-stent restenosis: current status in the era of drug-eluting stents.

Drug-eluting stents are revolutionizing interventional cardiology. Sirolimus-eluting stents are in widespread clinical use, associated with well-documented remarkably low restenosis rates, and a number of other agents appear promising in clinical trials. These human studies have been preceded by numerous animal studies, foremost among them the pig coronary model of in-stent restenosis (ISR).

Prophylaxis of contrast-induced nephropathy in patients undergoing coronary angiography.

Contrast-induced nephropathy (CIN) is a common complication of cardiac catheterization, reported to result in a 15% incidence of acute renal failure. Convincing evidence supports the prophylactic use of prehydration and low volumes of contrast medium. Recently, the antioxidant acetylcysteine has been shown to have a potential preventive role.

Percutaneous mitral valve repair: a feasibility study in an ovine model of acute ischemic mitral regurgitation.

Annuloplasty is the cornerstone of surgical mitral valve repair. A percutaneous transvenous catheter-based approach for mitral valve repair was tested by placing a novel annuloplasty device in the coronary sinus of sheep with acute ischemic mitral regurgitation. Mitral regurgitation was reduced from 3-4+ to 0-1+ in all animals (P < 0.

Pharmacologic reperfusion therapy for acute myocardial infarction.

Acute myocardial infarction (MI) remains a significant problem in terms of morbidity, mortality and healthcare costs. Pharmacologic reperfusion therapies for MI are becoming increasingly complex. This review therefore places contemporary pharmacologic MI developments into perspective.

Intravascular modalities for detection of vulnerable plaque: current status.

Progress in the diagnosis, treatment, and prevention of atherosclerotic coronary artery disease is dependent on a greater understanding of the mechanisms of coronary plaque progression. Autopsy studies have characterized a subgroup of high-risk, or vulnerable, plaques that result in acute coronary syndromes or sudden cardiac death. These angiographically modest plaques share certain pathologic characteristics: a thin, fibrous cap, lipid-rich core, and macrophage activity.

Targeting signaling pathways in heart failure by gene transfer.

Congestive heart failure represents an enormous clinical problem demanding effective therapeutic approaches. The varied etiologies of heart failure include abnormalities of ion handling, cellular signaling, neurohormonal control, and apoptosis, all of which are potentially amenable to genetic manipulation. Gene therapy holds the promise of retarding the progression, preventing, and perhaps reversing heart failure.

Toward a new blood vessel.

Strategies to treat atherosclerotic coronary artery disease include coronary artery bypass grafting (CABG), in which grafts are used to bypass atherosclerotic vessels and restore blood flow to the ischemic myocardium. The grafts used include healthy arteries or veins harvested from a separate site. Results with arterial grafts have been superior to venous grafts; promoting the practice of total arterial revascularization using only arterial grafts.