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Juan Jose Badimon

Publications and source records attributed to Juan Jose Badimon.

12 recordsLinked to original sources

Evolving concepts in the triad of atherosclerosis, inflammation and thrombosis.

Recent developments into antherothrombosis, the leading cause of morbidity and mortality in Western Society, may help to change our treatment strategy to a more casual approach. The composition of the atherosclerotic plaque, rather than the percent stenosis, appears to be a critical predictor for both risk of plaque rupture and subsequent thrombogenicity. A large lipid core, rich in tissue factor (TF) and inflammatory cells including macrophages, and a thin fibrous cap with compromise of its structural integrity by matrix degrading enzymes, such as metalloproteinases (MMPs), render a lesion susceptible to rupture and subsequent acute thrombosis. Thrombosis may lead to a complete occlusion or, in the case of mural thrombus or intraplaque hemorrhage, to plaque progression. Disruption of a vulnerable or unstable plaque (type IV and Va lesions of the AHA classification) with a subsequent change in plaque geometry and thrombosis may result in an acute coronary syndrome. The high-risk plaque tend to be relatively small, but soft or vulnerable to "passive" disruption because of high lipid content. Inflammatory processes are important components of all stages of atherosclerotic development, including plaque initiation and disruption. As such the early steps in atherosclerotic lesion formation are the over expression of endothelial adhesive protein (i.e. selectins, VCAM and ICAM), chemotactic factors (MCP-1), growth factors (M-CSF), and cytokines (IL-2) that will facilitate the recruitment, internalization and survival of blood-borne inflammatory cells into the vascular wall. Macrophages, following what appears to be a defense mission by protecting the vessel wall from excess lipid accumulation, may eventually undergo apoptosis with release of MMPs and TF. Specific cell recruitment in the vessel wall and build-up of the extracellular matrix are coordinated by a wide variety of stimulators and inhibitors. Active interaction of immune competent cells within the atherosclerotic lesions appears to play a pivotal role in the control of atherosclerotic plaque evolution and, therefore, deserves particular attention from the research community with the ultimate goal of improving preventive and therapeutic medical approaches. Inflammation, thrombosis and atherosclerosis are interdependent and define a triad within the complex pathogenic process of atherothrombosis.

Arteriosclerosis↗

From vulnerable plaque to vulnerable patient: a call for new definitions and risk assessment strategies: Part II.

Atherosclerotic cardiovascular disease results in >19 million deaths annually, and coronary heart disease accounts for the majority of this toll. Despite major advances in treatment of coronary heart disease patients, a large number of victims of the disease who are apparently healthy die suddenly without prior symptoms. Available screening and diagnostic methods are insufficient to identify the victims before the event occurs. The recognition of the role of the vulnerable plaque has opened new avenues of opportunity in the field of cardiovascular medicine. This consensus document concludes the following. (1) Rupture-prone plaques are not the only vulnerable plaques. All types of atherosclerotic plaques with high likelihood of thrombotic complications and rapid progression should be considered as vulnerable plaques. We propose a classification for clinical as well as pathological evaluation of vulnerable plaques. (2) Vulnerable plaques are not the only culprit factors for the development of acute coronary syndromes, myocardial infarction, and sudden cardiac death. Vulnerable blood (prone to thrombosis) and vulnerable myocardium (prone to fatal arrhythmia) play an important role in the outcome. Therefore, the term "vulnerable patient" may be more appropriate and is proposed now for the identification of subjects with high likelihood of developing cardiac events in the near future. (3) A quantitative method for cumulative risk assessment of vulnerable patients needs to be developed that may include variables based on plaque, blood, and myocardial vulnerability. In Part I of this consensus document, we cover the new definition of vulnerable plaque and its relationship with vulnerable patients. Part II of this consensus document will focus on vulnerable blood and vulnerable myocardium and provide an outline of overall risk assessment of vulnerable patients. Parts I and II are meant to provide a general consensus and overviews the new field of vulnerable patient. Recently developed assays (eg, C-reactive protein), imaging techniques (eg, CT and MRI), noninvasive electrophysiological tests (for vulnerable myocardium), and emerging catheters (to localize and characterize vulnerable plaque) in combination with future genomic and proteomic techniques will guide us in the search for vulnerable patients. It will also lead to the development and deployment of new therapies and ultimately to reduce the incidence of acute coronary syndromes and sudden cardiac death. We encourage healthcare policy makers to promote translational research for screening and treatment of vulnerable patients.

Animals↗

From vulnerable plaque to vulnerable patient: a call for new definitions and risk assessment strategies: Part I.

Atherosclerotic cardiovascular disease results in >19 million deaths annually, and coronary heart disease accounts for the majority of this toll. Despite major advances in treatment of coronary heart disease patients, a large number of victims of the disease who are apparently healthy die suddenly without prior symptoms. Available screening and diagnostic methods are insufficient to identify the victims before the event occurs. The recognition of the role of the vulnerable plaque has opened new avenues of opportunity in the field of cardiovascular medicine. This consensus document concludes the following. (1) Rupture-prone plaques are not the only vulnerable plaques. All types of atherosclerotic plaques with high likelihood of thrombotic complications and rapid progression should be considered as vulnerable plaques. We propose a classification for clinical as well as pathological evaluation of vulnerable plaques. (2) Vulnerable plaques are not the only culprit factors for the development of acute coronary syndromes, myocardial infarction, and sudden cardiac death. Vulnerable blood (prone to thrombosis) and vulnerable myocardium (prone to fatal arrhythmia) play an important role in the outcome. Therefore, the term "vulnerable patient" may be more appropriate and is proposed now for the identification of subjects with high likelihood of developing cardiac events in the near future. (3) A quantitative method for cumulative risk assessment of vulnerable patients needs to be developed that may include variables based on plaque, blood, and myocardial vulnerability. In Part I of this consensus document, we cover the new definition of vulnerable plaque and its relationship with vulnerable patients. Part II of this consensus document focuses on vulnerable blood and vulnerable myocardium and provide an outline of overall risk assessment of vulnerable patients. Parts I and II are meant to provide a general consensus and overviews the new field of vulnerable patient. Recently developed assays (eg, C-reactive protein), imaging techniques (eg, CT and MRI), noninvasive electrophysiological tests (for vulnerable myocardium), and emerging catheters (to localize and characterize vulnerable plaque) in combination with future genomic and proteomic techniques will guide us in the search for vulnerable patients. It will also lead to the development and deployment of new therapies and ultimately to reduce the incidence of acute coronary syndromes and sudden cardiac death. We encourage healthcare policy makers to promote translational research for screening and treatment of vulnerable patients.

Acute Disease↗

Role of risk factors in the modulation of tissue factor activity and blood thrombogenicity.

BACKGROUND: Several studies suggest a role for an increased circulating pool of tissue factor (TF) in atherothrombotic diseases. Furthermore, certain cardiovascular risk factors, such as diabetes, hyperlipemia, and smoking, are associated with a higher incidence of thrombotic complications. We hypothesized that the observed increased blood thrombogenicity (BT) observed in patients with type 2 diabetes mellitus may be mediated via an increased circulating tissue factor activity. We have extended our study to smokers and hyperlipidemic subjects. METHODS AND RESULTS: Poorly controlled patients with type 2 diabetes mellitus (n=36), smokers (n=10), and untreated hyperlipidemic subjects (n=10) were studied. Circulating TF was immunocaptured from plasma, relipidated, and quantified by factor Xa (FXa) generation in the presence of factor VIIa. BT was assessed as thrombus formation on the Badimon perfusion chamber. Patients with improvement in glycemic control showed a reduction in circulating TF (362+/-135 versus 243+/-74 pmol/L per min FXa, P=0.0001). A similar effect was observed in BT (15 445+/-1130 versus 12 072+/-596 microm/mm2, P=0.01). Two hours after smoking 2 cigarettes, TF was increased (217+/-72 versus 283+/-106 pmol/L per min FXa, P=0.003). Hyperlipidemic subjects showed higher TF (237+/-63 versus 195+/-44 pmol/L per min FXa, P=0.035) than healthy volunteers. CONCLUSIONS: These findings suggest that high levels of circulating TF may be the mechanism of action responsible for the increased thrombotic complications associated with the presence of these cardiovascular risk factors. These observations strongly emphasize the usefulness of the management of the patients based on their global risk assessment.

Cardiovascular Diseases↗

Pathogenetic concepts of acute coronary syndromes.

The propensity of plaque to disrupt is a major determinant of future ischemic events. Although they are distinct from one another, the atherosclerotic and thrombotic processes appear to be interdependent and may be integrated under the term "atherothrombosis." It is now clear that plaque composition, rather than the percent stenosis, is a major determinant of plaque vulnerability. Plaque disruption seems to depend on both passive and active phenomena and is not purely mechanical. Inflammation (activation of monocytes/macrophages) is a major determinant of both plaque vulnerability and thrombogenicity as they relate to plaque disruption. In one-third of acute coronary syndromes, there is, however, no plaque disruption but only superficial erosion of a markedly stenotic, fibrotic plaque. In these cases, thrombus formation may be exacerbated by a hyperthrombogenic state present in patients with certain systemic risk factors. The endothelium plays a pivotal role in vascular homeostasis and hemostasis. This dynamic organ regulates blood thrombogenicity as well as contractile, secretory, and mitogenic activities in the vessel wall. Some classic risk factors induce endothelial dysfunction by reducing the bioavailability of nitric oxide, increasing tissue endothelin-1, and activating pro-inflammatory signaling pathways. Vascular hemostasis, which is the maintenance of blood fluidity and vascular integrity, is achieved by counter-balancing the intrinsic clotting tendency of blood. As a consequence of the central role of endothelial cells in hemostatic control, a dysfunctional endothelium will generate a pro-thrombotic environment favoring development of atherosclerotic lesions and thrombotic complications.

Acute Disease↗

Statins and plaque stability.

3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are now the standard of care for patients with hypercholesterolaemia. This class of inhibitors, known as 'statins', has been shown to reduce cardiovascular morbidity and mortality. Accumulating data demonstrates a variety of mechanisms in which HMG-CoA reductase inhibition benefits the cardiovascular system. This review will discuss the pharmacology, clinical trials, and mechanisms, besides lipid lowering, of statin therapy.

Arteriosclerosis↗

The vulnerable plaque and acute coronary syndromes.

The interaction between the vulnerable atherosclerotic plaque and thrombus formation, a process referred to as atherothrombosis, is the cornerstone of acute coronary syndromes. Advances in noninvasive imaging have helped to identify novel approaches to plaque stabilization, with the potential to prevent plaque rupture, including lifestyle modification and dietary adjustments, as well as pharmacologic interventions such as statins. Following an acute coronary event, strategies combining mechanical and pharmacologic therapies provide considerable advances in prevention of subsequent cardiac events. Pharmacologic strategies to prevent and treat thrombotic complications related to acute coronary syndromes have been developed to dissolve preformed thrombi and to inhibit thrombogenesis. These regimens focus on inhibiting thrombin, preventing thrombi generation, blocking the initiation of coagulation, inhibiting platelet activation, and increasing fibrinolysis.

Anticholesteremic Agents↗

Biologic aspects of vulnerable plaque.

Atherosclerosis and its thrombotic complications are the major cause of morbidity and mortality in the industrialized world. The progression of atherosclerotic plaques in coronary circulation is modulated by several risk factors. It is now clear that plaque composition is a major determinant of plaque disruption and superimposed thrombosis. Plaque vulnerability, defined as the propensity of plaques to disrupt, is further determined by intrinsic and extrinsic triggering factors. After disruption, the fatty core of the plaque and its high content of tissue factor provide a powerful substrate for the activation of the coagulation cascade. Plaque disruption can be clinically silent or cause symptoms of ischemia depending on thrombus burden and the degree of vessel occlusion. In addition, plaque disruption and subsequent healing are recognized to play key roles in the rapid plaque progression. This review looks at the mechanisms underlying the development and progression of atherosclerotic plaques, factors leading to plaque rupture and subsequent thrombosis, and their clinical consequences as potential targets for future research.

Biomarkers↗

Antithrombotic effects of DX-9065a, a direct factor Xa inhibitor: a comparative study in humans versus low molecular weight heparin.

BACKGROUND: Recent evidence suggests that TF may play a causal role in acute coronary syndromes, and may be an important therapeutic target. Several inhibitors of TF, coagulation factors VIIa and Xa are under investigation as novel antithrombotic approaches. We compared the antithrombotic effects of DX-9065a, a new FXa inhibitor, vs. enoxaparin. METHODS AND RESULTS: The protocol was an open-label crossover study. Subjects (n = 6) participated in 3 consecutive study-arms: a) enoxaparin + ASA (1 mg/Kg s. c + 162 mg/day x 3 days), b) three escalating doses of DX-9065a (1 mg bolus + 0.25 mg/h x 2 h, followed by an additional 1 mg bolus + 0.625 mg/h x 2 h and, a final 1 mg bolus + 1.25 mg/h x 2 h), and c) the same doses of DX-9065a in Arm 2 plus ASA pre-treatment. The antithrombotic effects were assessed using the Badimon perfusion chamber at each dose level. The administration of DX-9065a whether alone or combined with ASA significantly inhibited thrombus formation at high and low shear rate conditions while enoxaparin did not have a significant effect. Furthermore, these antithrombotic effects were obtained without significant prolongations of the standard coagulation parameters as those induced by enoxaparin. CONCLUSIONS: The direct inhibition of FXa by DX-9065a appears to be a safe and effective new approach for preventing the thrombotic complications of atherosclerotic disease. The clinical effectiveness of the direct FXa inhibitors should be further investigated.

Adult↗