Increased prevalence of aortic fatty streaks in cholesterol-fed rabbits administered intravenous cocaine: the role of vascular endothelium

Cocaine-Associated Myocardial Infarction

Myocardial ischaemia and infarction has become a well-recognized sequelae of cocaine use. The possibility of recent cocaine use should be assessed in patients with potential myocardial ischaemia because the treatment of patients with myocardial ischaemia related to cocaine differs from that of patients with myocardial ischaemia unrelated to cocaine. Patients with cocaine-associated myocardial ischaemia should receive initial treatment with benzodiazepines to decrease central adrenergic stimulation. Aspirin should be used to reduce thrombus formation, and nitroglycerin to reverse coronary vasoconstriction. Patients with continued ischaemia can be treated with either low doses of phentolamine, or verapamil. If ischaemia continues after treatment with these agents mechanical reperfusion or thrombolytic therapy should be considered depending upon the clinical circumstances. Patients with myocardial ischaemia secondary to cocaine should not receive treatment with beta adrenergic antagonists as these agents enhance coronary vasoconstriction thereby worsening ischaemia.

Cocaine and coronary artery diseases: a systematic review of the literature

Cocaine is associated with important cardiac complications such as sudden death, acute myocarditis, dilated cardiomyopathy, life-threatening arrhythmias, and myocardial ischemia as well as infarction. It is well known that cocaine may induce vasospasm through adrenergic stimulation of the coronary arteries. Moreover, cocaine may promote intracoronary thrombosis, triggered by alterations in the plasma constituents, and platelet aggregation, leading to subsequent myocardial infarction. The long-term use of cocaine may stimulate atherosclerosis, probably through endothelial cell dysfunction. Significant and severe coronary atherosclerosis is common in young chronic cocaine users and there is probably a relationship between the duration and frequency of cocaine use and the extent of coronary disease.

Cocaine: A Rare Cause of Left-Sided Renal Infarction

Cocaine abuse is commonly associated with myocardial ischemia, mesenteric ischemia, and cerebrovascular accidents. Renal infarction is an uncommon complication of cocaine abuse. Various mechanisms have been postulated for this cocaine-related injury. There are only 15 cases reported on cocaine-induced renal infarction. Among the cases with available data, very few cases had left kidney involvement. We report a case of a 65-year-old African American man with history of cocaine abuse who presented with left flank pain and had left renal infarction.

A review on renal toxicity profile of common abusive drugs

Drug abuse has become a major social problem of the modern world and majority of these abusive drugs or their metabolites are excreted through the kidneys and, thus, the renal complications of these drugs are very common. Morphine, heroin, cocaine, nicotine and alcohol are the most commonly abused drugs, and their use is associated with various types of renal toxicity. The renal complications include a wide range of glomerular, interstitial and vascular diseases leading to acute or chronic renal failure. The present review discusses the renal toxicity profile and possible mechanisms of commonly abused drugs including morphine, heroin, cocaine, nicotine, caffeine and alcohol.

Characteristics and outcomes of cocaine-related spontaneous intracerebral hemorrhages

To date there is only one single-center study that has exclusively reported characteristics, location, and outcomes of spontaneous intracerebral hemorrhages (ICH) among cocaine users. We aimed to describe the radiological location and characteristics along with clinical outcomes of spontaneous ICH in a similar population. We conducted a retrospective chart review of consecutive patients admitted to a tertiary care hospital, with a spontaneous ICH, who had a urine drug screen performed within 48 hours of admission. Exposure to cocaine was defined by a positive urine drug screen within 48 hours of hospital admission. Demographics, radiographic features of ICH, and short-term clinical outcomes of patients with a positive urine drug screen were analyzed and compared with the cocaine negative group. Among the 102 patients analyzed, 20 (19.6%) had documented exposure to cocaine. There was a predominance of males in both groups with significantly more Blacks in the cocaine positive group (P = 0.0246). A statistically significant number of patients with cocaine use had ICH in a subcortical location (P = 0.0224) when compared to cocaine negative patients. There was no difference in GCS, ICH volume, intraventricular extension, ICU days, hospital days, hospital cost, mortality, and ICH score. ICH in cocaine use is more frequently seen in the subcortical location.

Epidemic of illicit drug use, mechanisms of action/addiction and stroke as a health hazard

Drug abuse robs individuals of their jobs, their families, and their free will as they succumb to addiction; but may cost even more: a life of disability or even life lost due to stroke. Many illicit drugs have been linked to major cardiovascular events and other comorbidities, including cocaine, amphetamines, ecstasy, heroin, phencyclidine, lysergic acid diethylamide, and marijuana. This review focuses on available epidemiological data, mechanisms of action, particularly those leading to cerebrovascular events, and it is based on papers published in English in PubMed during 1950 through February 2011. Each drug's unique interactions with the brain and vasculature predispose even young, healthy people to ischemic or hemorrhagic stroke. Cocaine and amphetamines have the strongest association with stroke. However, the level of evidence firmly linking other drugs to stroke pathogenesis is weak. Large epidemiological studies and systematic evaluation of each drug's action on the brain and cardiovascular system are needed to reveal the full impact of drug use on the population.

Relationship between cocaine use and coronary artery disease in patients with symptoms consistent with an acute coronary syndrome

OBJECTIVES

Observational studies of patients with cocaine-associated myocardial infarction have suggested more coronary disease than expected on the basis of patient age. The study objective was to determine whether cocaine use is associated with coronary disease in low- to intermediate-risk emergency department (ED) patients with potential acute coronary syndrome (ACS).

METHODS

The authors conducted a cross-sectional study of low- to intermediate-risk patients<60 years of age who received coronary computerized tomographic angiography (CTA) for evaluation of coronary artery disease (CAD) in the ED. Patients were classified into three groups with respect to CAD: maximal stenosis <25%, 25% to 49%, and ≥50%. Prespecified multivariate modeling (generalized estimating equations) was used to assess relationship between cocaine and CAD.

RESULTS

Of 912 enrolled patients, 157 (17%) used cocaine. A total of 231 patients had CAD ≥25%; 111 had CAD ≥50%. In univariate analysis, cocaine use was not associated with a lesion 25% or greater (12% vs. 14%; relative risk [RR]=0.89, 95% confidence interval [CI]=0.5 to 1.4) or 50% or greater (12% vs. 11%; RR=1.15, 95% CI=0.6 to 2.3). In multivariate modeling adjusting for age, race, sex, cardiac risk factors, and Thrombosis in Myocardial Infarction (TIMI) score, cocaine use was not associated with the presence of any coronary lesion (adjusted RR=0.95, 95% CI=0.69 to 1.31) or coronary lesions 50% or greater (adjusted RR=0.78, 95% CI=0.45 to 1.38). There was also no relationship between repetitive cocaine use and coronary calcifications or between recent cocaine use and CAD.

CONCLUSIONS

In symptomatic ED patients at low to intermediate risk of an ACS, cocaine use was not associated with an increased likelihood of coronary disease after adjustment for age, race, sex, and other risk factors for coronary disease.

Presence and extent of coronary artery disease by cardiac computed tomography and risk for acute coronary syndrome in cocaine users among patients with chest pain

Cocaine users represent an emergency department (ED) population that has been shown to be at increased risk for acute coronary syndrome (ACS); however, there is controversy about whether this higher risk is mediated through advanced atherosclerosis. Thus, we aimed to determine whether history of cocaine use is associated with ACS and coronary artery disease. In this matched cohort study, we selected patients with a history of cocaine use and age- and gender-matched controls from a large cohort of consecutive patients who presented with acute chest pain to the ED. Coronary atherosclerotic plaque as detected by 64-slice coronary computed tomography was compared between the groups. Among 412 patients, 44 had a history of cocaine use (9%) and were matched to 132 controls (mean age 46 +/- 6 years, 86% men). History of cocaine use was associated with a sixfold higher risk for ACS (odds ratio 5.79, 95% confidence interval 1.24 to 27.02, p = 0.02), but was not associated with a higher prevalence of any plaque, calcified plaque, or noncalcified plaque (all p>0.58) or the presence of significant stenosis (p = 0.09). History of cocaine use was also not associated with the extent of any, calcified, or noncalcified plaque (all p>0.12). These associations persisted after adjustment for other cardiovascular risk factors. In conclusion, in patients presenting to the emergency department with acute chest pain, history of cocaine use is associated with an increase in risk for ACS; however, this was not attributable to a higher presence or extent of coronary atherosclerotic plaque.

Management of cocaine-induced cardiac arrhythmias due to cardiac ion channel dysfunction

Cocaine use is common in many areas of the world, particularly the United States and Western Europe. Toxicity following the use of cocaine is associated with a wide range of clinical features. In this review, we will focus on the cocaine-associated cardiac arrhythmias and, in particular, some of the controversies in their etiology and management. Cocaine can produce arrhythmias either through the production of myocardial ischemia or as a direct result of ion channel alterations. Excessive catecholamines, combined with sodium and potassium channel blockades, give rise to a wide variety of supra-ventricular and ventricular rhythms. The animal and human evidence for ion channel dysfunction is reviewed, and the effects of catecholamines are followed from the cardiac action potential to the development of arrhythmias. Finally, theoretical constructs are combined with existing evidence to develop a rational treatment strategy for patients with cocaine-induced cardiac arrhythmias. In particular, we review the evidence concerning the controversies relating to the use of lidocaine in comparison with sodium bicarbonate, in terms of QRS prolongation secondary to sodium channel blockade.

Can cocaine abuse exacerbate the cardiac toxicity of human immunodeficiency virus?

Both cocaine use and human immunodeficiency virus (HIV) infection alone have been associated with an increased incidence of cardiac dysfunction. Concomitant exposure to cocaine and HIV infection may exacerbate the cardiac toxicity of either agent alone, a hypothesis that is examined in this review article. A possible unifying hypothesis based on enhancement of adrenergic stimulation is proposed.

Molecular analysis of cocaine-induced endothelial dysfunction: role of endothelin-1 and nitric oxide

Cocaine remains the most frequently used illicit substance. Although cocaine-induced atherosclerosis is well documented, its mechanism of action on human vascular endothelial cells has not been determined. Nitric oxide (NO) and endothelin-1 (ET-1) are involved in endothelial cell activation and leukocyte recruitment. The present study monitored the effects of cocaine on NO and ET-1 production in human aortic endothelial cells (HAECs) and the effects of sodium nitroprusside (SNP) and BQ-123 on leukocyte adhesion to HAECs. Acute exposure to cocaine (1 and 3 muM) significantly increased ET-1 production (2-fold) and ET-1 receptor type-A (ET(A)R) protein expression, within 6-12 h. Cocaine exposure for a longer duration (24-72 h) showed a temporal decrease in both NO production and endothelial NO-synthase (eNOS) expression. The cocaine-mediated suppression of NO was ameliorated by co-treatment of cells with the ET(A)R blocker, BQ-123 (5 muM). Furthermore, both short-term (24 h) and long-term (72 h) exposure to cocaine increased endothelial adhesion of monocytes (U937 cells) by 20% and 40%, respectively, which were also suppressed by BQ-123 and SNP co-treatment. These data suggest that a concomitant increase in both ET-1 and ET(A)R expression in cocaine exposed HAECs may enhance signaling via the ET(A)R which decreases eNOS expression and NO production, and ultimately results in endothelial activation and leukocyte adhesion. Our findings implicate a molecular mechanism of action of cocaine and a therapeutic effect of ET(A)R-specific inhibitor in suppressing the cocaine-induced endothelial dysfunction.

Cocaine use and hypertensive renal changes in HIV-infected individuals

BACKGROUND AND OBJECTIVES

Cocaine causes kidney damage, but data linking cocaine use to chronic kidney disease in HIV patients is not described. This study was conducted to evaluate the possible association of cocaine use and histopathologic findings on biopsy in this population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Kidney biopsies that were performed in HIV-infected patients during the course of 11 yr were reviewed. Demographic and clinical data were collected. Hypertensive changes were defined on the basis of the Banff 97 classification. Criteria of both arterial intimal fibrosis and thickening and hyaline arteriolosclerosis were used and graded as absent (0), mild (1), moderate (2), and severe (3). Hypertensive renal changes were considered present when the combined pathology score was > or = 2. To minimize confounding, those with hypertension or diabetes were excluded.

RESULTS

Of the 193 HIV patients who underwent kidney biopsy, 53 had no history of hypertension or diabetes with HIV infection. Of those, 29 (55%) had hypertensive renal changes on kidney biopsy. Cocaine use was present in 16 (55%) of 29 with hypertensive renal changes compared with six (25%) of 24 without hypertensive renal changes (odds ratio [OR] 3.7; 95% confidence interval [CI] 1.2 to 11.7). In the adjusted analyses, only age (/yr; OR 1.08; 95% CI 1.00 to 1.16) and cocaine use (OR 3.55; 95% CI 1.04 to 12.14) were significantly associated with hypertensive renal changes on renal biopsy.

CONCLUSIONS

Cocaine use is associated with hypertensive renal changes in HIV-infected patients in the absence of hypertension and diabetes.

Chronic nephropathies of cocaine and heroin abuse: a critical review

Renal disease in cocaine and heroin users is associated with the nephrotic syndrome, acute glomerulonephritis, amyloidosis, interstitial nephritis, and rhabdomyolysis. The pathophysiologic basis of cocaine-related renal injury involves renal hemodynamic changes, glomerular matrix synthesis and degradation, and oxidative stress and induction of renal atherogenesis. Heroin is the most commonly abused opiate in the United States. Previous studies identified a spectrum of renal diseases in heroin users. The predominant renal lesion in black heroin users is focal segmental glomerulosclerosis and in white heroin users is membranoproliferative glomerulonephritis. Although the prevalence of heroin use in the United States has increased, the incidence of "heroin nephropathy" has declined. Because reports of heroin nephropathy predated the surveillance of hepatitis C virus and HIV, the varied findings might be related to the spectrum of viral illnesses that are encountered in injection drug users. Socioeconomic conditions, cultural and behavioral practices, or differences in genetic susceptibilities may be more associated with the development of nephropathy in heroin users than the drug's pharmacologic properties. Administration of cocaine in animal models results in nonspecific glomerular, interstitial, and tubular cell lesions, but there is no animal model of heroin-associated renal disease. The heterogeneity of responses that are associated with heroin is not consistent with a single or simple notion of nephropathogenesis. There are no well-designed, prospective, epidemiologic studies to assess the incidence and the prevalence of renal disease in populations of opiate users and to establish the validity of a syndrome such as heroin nephropathy. It is concluded although there is a paucity of evidence to support a heroin-associated nephropathy, the evidence from in vitro cellular and animal studies to support the existence of cocaine-induced renal changes is more convincing.

Cocaine and coronary calcification in young adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

BACKGROUND

Cocaine use is associated with myocardial ischemia and infarction, but it is unclear whether this is only because of the acute effects of cocaine on heart rate, blood pressure, and vasomotor tone or whether accelerated atherosclerosis from long-term exposure to cocaine also contributes.

METHODS

We sought to measure the association between cocaine exposure and coronary calcification, a marker for atherosclerosis, among participants in the CARDIA Study who received computed tomography scanning and answered questions about illicit drug use at the year 15 examination in 2000-2001.

RESULTS

Among 3038 CARDIA participants (age 33-45 years, 55% women and 45% black), past cocaine exposure was reported by 35% and was more common among men, smokers, drinkers, and participants with less education. Powdered cocaine exposure was more common among whites, crack cocaine among blacks. Before adjustment, cocaine exposure was strongly associated with coronary calcification. After adjusting for age, sex, ethnicity, socioeconomic status, family history, and habits, however, these associations disappeared: adjusted odds ratios for coronary calcification were 0.9 (95% CI 0.6-1.3) for 1 to 10, 1.2 (95% CI 0.8-1.7) for 11 to 99, and 1.0 (95% CI 0.6-1.6) for > or =100 lifetime episodes of cocaine use, in comparison with none. Sex, tobacco, and alcohol use appeared to be primarily responsible for the confounding we observed in unadjusted models.

CONCLUSION

We found no evidence of a causal relationship between long-term exposure to cocaine and coronary calcification and conclude that acute nonatherogenic mechanisms probably explain most cocaine-associated myocardial infarction.

Cocaine-induced renal infarction: report of a case and review of the literature

Background

Cocaine abuse has been known to have detrimental effects on the cardiovascular system. Its toxicity has been associated with myocardial ischemia, cerebrovascular accidents and mesenteric ischemia. The pathophysiology of cocaine-related renal injury is multifactorial and involves renal hemodynamic changes, alterations in glomerular matrix synthesis, degradation and oxidative stress, and possibly induction of renal atherogenesis. Renal infarction as a result of cocaine exposure, however, is rarely reported in the literature.

Case presentation

A 48 year-old male presented with a four-day history of severe right flank pain following cocaine use. On presentation, he was tachycardic, febrile and had severe right costovertebral angle tenderness. He had significant proteinuria, leukocytosis and elevated serum creatinine and lactate dehydrogenase. Radiographic imaging studies as well as other screening tests for thromboembolic events, hypercoagulability states, collagen vascular diseases and lipid disorders were suggestive of Cocaine-Induced Renal Infarction (CIRI) by exclusion.

Conclusion

In a patient with a history of cocaine abuse presenting with fevers and flank pain suggestive of urinary tract infection or nephrolithiasis, cocaine-induced renal infarction must be considered in the differential diagnosis. In this article, we discuss the prior reported cases of CIRI and thoroughly review the literature available on this disorder. This is important for several reasons. First, it will allow us to discuss and elaborate on the mechanism of renal injury caused by cocaine. In addition, this review will demonstrate the importance of considering the diagnosis of CIRI in a patient with documented cocaine use and an atypical presentation of acute renal injury. Finally, we will emphasize the need for a consensus on optimal treatment of this disease, for which therapy is not yet standardized.

Cocaine and cardiovascular toxicity

Over the past 10 years a great deal has been learned about the cardiovascular effects of cocaine. In particular, the acute effects of cocaine have been studied extensively. Upon acute administration cocaine increases blood pressure and heart rate, primarily through an action on the sympathetic nervous system. Cocaine also suppresses the baroreflex response and vagal tone, further contributing to its effects on heart rate. At the same time cocaine is increasing the work-load on the heart it induces coronary artery vasoconstriction, potentially leading to cardiac ischemia. At higher doses cocaine can depress ventricular function and slow electrical conduction in the heart. Both these effects appear to be mediated by cocaine's local anesthetic action. The effects of cocaine mediated by the sympathetic nervous system are greatly reduced in anesthetized animals. Further, when cocaine is administered repeatedly over a short period of time, acute tolerance can develop to the sympathomimetic effects of cocaine. In contrast, the effects of cocaine mediated by its local anesthetic action do not appear blunted by anesthesia or susceptible to acute tolerance. With chronic administration, higher doses appear to induce tolerance while lower doses may induce sensitization to cocaine's sympathomimetic effects. Cocaine also induces a variety of pathological changes in the heart, including myocardial contraction band necrosis and ventricular hypertrophy. These effects of cocaine on the heart can all contribute to potentially lethal cardiovascular events. In addition to the effects of cocaine alone, the metabolites of cocaine may also contribute to cocaine's cardiovascular toxicity, and both licit and illicit drugs used in combination with cocaine might potentially alter its cardiovascular effects.

Effect of acute intravenous cocaine administration on endothelium-dependent vasodepressor responses to acetylcholine

BACKGROUND

Cardiovascular events commonly associated with acute and chronic cocaine abuse include coronary vasospasm, arrhythmias, myocardial infarction, and sudden death. It has been suggested that cocaine causes endothelial dysfunction and vasoconstriction by inhibiting local production of nitric oxide and that endothelial dysfunction may be involved in the cardiovascular events associated with cocaine use. The present study investigated the effect of acute intravenous cocaine administration on endothelium-dependent vasodepressor responses to acetylcholine in the anesthetized rat.

METHODS AND RESULTS

Rats were anesthetized with intraperitoneally Inactin (140 mg/kg) and catheters were inserted into the jugular vein and iliac artery for the injection of drugs and measurement of systemic arterial pressure. A thermistor catheter was advanced to the aortic arch for the measurement of cardiac output via the thermal dilution technique. A 5 mg/kg intravenous dose of cocaine, which enhances the vasopressor response to norepinephrine and blocks the vasopressor response to tyramine, had no effect on the vasodepressor response to the endothelium-dependent vasodilator acetylcholine. In addition, responses to the nitric oxide-donor sodium nitroprusside and the vasoconstrictor peptide angiotensin II were not altered by administration of cocaine.

CONCLUSIONS

Acute administration of cocaine in a dose that blocks norepinephrine uptake into adrenergic terminals had no effect on endothelial function as measured by the absence of an effect on the vasodepressor response to intravenous injections of acetylcholine. Although chronic cocaine exposure has been shown to cause vascular dysfunction, eventually leading to impairment of the nitric oxide pathway, it appears that acute cocaine administration does not inhibit this pathway in the anesthetized rat.

Cardiovascular disorders associated with cocaine use: myths and truths

Cocaine produces a pattern of cardiovascular responses that are associated with apparent myocardial ischemia, arrhythmias, and other life-threatening complications in some individuals. Despite recent efforts to better understand the causes of cocaine-induced cardiovascular dysfunction, there remain a number of unanswered questions regarding the specific mechanisms by which cocaine elicits hemodynamic responses. This review will describe the actions of cocaine on the cardiovascular system and the evidence for the mechanisms by which cocaine elicits hemodynamic and pathologic responses in humans and animals. The emphasis will be on experimental data that provide the basis for our understanding of the mechanisms of cardiovascular toxicity associated with cocaine. More importantly, this review will identify several controversies regarding the causes of cocaine-induced cardiovascular toxicity that as yet are still debated. The evidence supporting these findings will be described. Finally, this review will outline the obvious deficits in our current concepts regarding the cardiovascular actions of cocaine in hope of encouraging additional studies on this grave problem in our society.

Long-term follow-up of coronary artery disease presenting in young adults

OBJECTIVES

This study evaluated long-term survival and predictors of elevated risk for young adults diagnosed with coronary artery disease (CAD).

BACKGROUND

Coronary artery disease is rarely seen in young adults. Traditional cardiac risk factors have been studied in small series; however, many questions exist.

METHODS

We identified 843 patients under age 40 with CAD diagnosed by coronary angiography from 1975 to 1985. Death, hypertension, gender, family history, prior myocardial infarction (MI), diabetes, heart failure, angina class, number of diseased vessels, ejection fraction (EF), Q-wave infarction, in-hospital death, and initial therapy were studied. Patients were followed for 15 years.

RESULTS

The mean age was 35 for women (n = 94) and 36 for men (n = 729). The average EF was 55%. Fifty-eight percent of the subjects had single-vessel disease, and 10% were diabetic. The strongest predictors of long-term mortality were a prior MI (hazard ratio [HR] 1.32, 95% confidence interval [CI] 1.00 to 1.73), New York Heart Association class II heart failure (HR 1.75, 95% CI 1.03 to 2.97), and active tobacco use (HR 1.59, 95% CI 1.14 to 2.21). Revascularization, rather than medical therapy, was associated with lower mortality (coronary angioplasty: HR 0.51, 95% CI 0.32 to 0.81; coronary artery bypass graft: HR 0.68, 95% CI 0.50 to 0.94). Overall mortality was 30% at 15 years. Patients with diabetes had 15-year mortality of 65%. Those with prior MI had 15-year mortality of 45%, and patients with an EF <30% a mortality of 83% at 15 years.

CONCLUSIONS

Coronary disease in young adults can carry a poor long-term prognosis. A prior MI, diabetes, active tobacco abuse, and lower EF predict a significantly higher mortality.

COCAINE USE AND ACUTE MYOCARDIAL INFARCTION

Cocaine use in the United States is widespread, affecting more than 30 million Americans. Although many of these persons do not seek healthcare, the overriding cause for hospitalization is cocaine-associated chest pain. Because only a minority of these patients suffer myocardial injury, it is important to exclude even rarer life-threatening causes for chest pain, such as aortic dissection or pneumothorax. Following that, a thorough knowledge of the pathophysiology and existing literature helps to provide cost-effective care, which focuses resources on those patients most likely to suffer complications. Regardless of the severity of complications, referral to cocaine detoxification programs, counseling, social support, and outpatient follow-up care for modification of cardiac risk factors is a fundamental component of long-term patient care.

Cocaine and the kidney: a synthesis of pathophysiologic and clinical perspectives

Cocaine abuse has reached epidemic proportions in the United States, and several forms of renal disease have been associated with this widespread use. The hemodynamic actions of cocaine, as well as its effects on matrix synthesis, glomerular inflammation, and glomerulosclerosis, may contribute to renal injury. Cocaine abuse has been associated with various forms of acute renal failure and acid-base and/or electrolyte disorders and may also have a role in the progression of chronic renal failure to end-stage renal disease. In utero exposure to cocaine has been associated with urogenital tract anomalies. Medical management of a hypertensive emergency caused by acute cocaine toxicity requires a multisystem approach, with close monitoring of cardiac, neurological, and renal functions.

Cocaine-induced increase in the permeability function of human vascular endothelial cell monolayers

The effects of cocaine on endothelial cell macromolecular transport, electrical resistance, and morphology were assessed. In confluent endothelial monolayers grown on microporus filters, cocaine (0.01 to 1 mmol/L) induced a rapid concentration-dependent increase in permeability to peroxidase and low density lipoprotein. Along with increased transport, the cocaine effect was paralleled by a decrease in transendothelial electrical resistance. Alterations in membrane resistance were fully reversible following washout of the drug, providing evidence that cocaine does not cause permanent injury to the integrity of the monolayer. Cocaines major metabolites, benzoylecgonine and ecgonine methyl ester, had minimal effect on electrical resistance properties, whereas monolayer impedance was markedly depressed by the novel cocaine/alcohol metabolite, cocaine ethyl ester (cocaethylene). Morphologic studies of cocaine-treated endothelial cells revealed a marked disruption of F-actin and the formation of intercellular gaps; no evidence of cell lysis and/or detachment was noted. Forskolin, a potent activator of adenylate cyclase known to promote the endothelial cell barrier function, impaired cocaine-induced changes in electrical resistance and morphology. Cocaine, however, had no effect on resting levels of intracellular adenosine 3',5'-cyclic monophosphate (cAMP) in confluent endothelial monolayers. In summary, the results indicate that cocaine directly induces structural defects in the endothelial cell barrier which enhance the transport of macromolecular tracers, the mechanism does not appear to involve intracellular cAMP.

Evaluation of patients with chest pain after cocaine use

Cocaine remains the most common cause of illicit drug-related visits to emergency departments, 40% of which result from chest pain. It is estimated that over half of the 64,000 patients evaluated annually for cocaine-associated chest pain will be admitted to hospitals for the evaluation of myocardial ischemia or infarction, at a health care cost of over eighty million dollars. Although the link between cocaine use and myocardial ischemia is well established, only about 6% of patients with cocaine-associated chest pain will demonstrate biochemical evidence of myocardial infarction. This article focuses on the evaluation of patients with chest pain following cocaine use, and concentrates on ways to improve diagnosis, management, and utilization of health care services.

Predictors of coronary artery disease in patients with cocaine-associated myocardial infarction. Cocaine-Associated Myocardial Infarction (CAMI) Study Group

PURPOSE

To identify clinical criteria predictive of underlying coronary artery disease in patients with cocaine-associated myocardial infarction.

PATIENTS AND METHODS

Using a retrospective cross-sectional study design at 29 acute care hospitals, we identified 70 patients with cocaine-associated myocardial infarction who had a determination of the presence or absence of coronary artery disease. Clinical characteristics of patients with coronary artery disease (> 50% stenosis on cardiac catheterization or reversible ischemia on stress test) were compared with patients without coronary artery disease (< 50% stenosis on cardiac catheterization).

RESULTS

Compared with patients without coronary artery disease (n = 21), patients with coronary artery disease (n = 49) were older (42 versus 31 years; P < 0.001), had more traditional cardiac risk factors (2.3 versus 1.5; P < 0.001), more frequent history of hypertension (odds ratio [OR], 5.3; 95% confidence interval [CI], 1.4 to 20.4); more frequent family history of myocardial infarction (OR, 4.4; 95% CI, 1.3 to 15.1), more bradydysrhythmias (OR, 8.0; 95% CI, 1.0 to 65.5), and more likely to have an inferior infarct location (P = 0.04).

CONCLUSION

Age, number of cardiac risk factors, location of myocardial infarction, and bradydysrhythmias predict underlying coronary artery disease in patients with cocaine-associated myocardial infarction. If validated, this knowledge may be used to develop a medically appropriate, cost-effective evaluation strategy for patients following cocaine-associated myocardial infarction.

Immunization with cholesterol-rich liposomes induces anti-cholesterol antibodies and reduces diet-induced hypercholesterolemia and plaque formation

Immunization of rabbits with a protein-free formulation consisting of liposomes containing 71% cholesterol and lipid A as an adjuvant induced anticholesterol antibodies that caused complement-dependent lysis of liposomes lacking lipid A. The antibodies, immunoglobulin G (IgG) and immunoglobulin M (IgM), also recognized nonoxidized crystalline cholesterol as an antigen by enzyme-linked immunosorbent assay (ELISA). The effects of immunization against cholesterol on elevations in serum cholesterol and development of atherosclerosis were examined in rabbits fed a diet containing 0.5% to 1.0% cholesterol. Although the mean serum cholesterol level, mainly in the form of very-low-density lipoprotein cholesterol, rose as much as 60-fold in the nonimmunized rabbits, the elevation was significantly less--as much as 35% lower--in the immunized rabbits. Elevation of serum cholesterol was accompanied by an apparent drop in the level of antibodies on initiating the diet, followed by a rebound on stopping the diet, thus suggesting that the antibodies were adsorbed to cholesterol that was present in circulating lipoproteins. When lipoprotein fractions--composed of either very-low-density and intermediate-density lipoproteins derived from cholesterol-fed nonimmunized rabbits or human low-density lipoproteins--were tested as capture antigens by solid-phase ELISA, reactivity was observed with IgG and IgM antibodies present in the serum of immunized rabbits. Immunization also resulted in a marked decrease in the risk of developing atherosclerosis. Analysis of aortic atherosclerosis by quantitative histologic examination and fatty streaks by automated morphometric probability-of-occurrence mapping showed diminished atherosclerosis in most areas of the aorta in vaccine recipients. It is proposed that immunization with liposomes containing 71% cholesterol and lipid A can reduce diet-induced hypercholesterolemia and atherosclerosis.