Cocaine-associated myocardial infarction: Features of diagnosis and treatment

Temporal relation of myocardial infarction with cocaine use was first reported in 1982, coronary spasm being the presumed aetiology since most patients presented with normal coronary arteries. However, severe and diffused coronary atherosclerosis is also common in cocaine users with myocardial infarction. The management of these patients presenting with chest pain includes therapy directed to antagonize sympathetic activation and mechanical reperfusion or thrombolytic therapy if ischaemia continues.

Acute myocardial infarction in young adults who abuse amphetamines

BACKGROUND

Case reports suggest a link between methamphetamine abuse and acute myocardial infarction (AMI), but no epidemiologic studies have examined this link. Our objective was to test the hypothesis that young adults who abuse amphetamines are at higher risk for AMI.

METHODS

In this study of 3,148,165 discharges from Texas hospitals in a quality indicators database during 2000-2003, among persons aged 18-44 years we identified 11,011 AMIs, defined according to the Agency for Healthcare Research and Quality's AMI mortality inpatient quality indicator.

RESULTS

In a multiple logistic regression analysis - while controlling for cocaine abuse, alcohol abuse, tobacco use, hypertension, diabetes mellitus, lipid disorders, obesity, congenital defects, and coagulation defects - amphetamine abuse was significantly associated with AMI (adjusted odds ratio=1.61; 95% CI=1.24-2.04, p=0.0004). The rate of AMIs among amphetamine abusers increased significantly from 2000 to 2003. The population attributable risk suggests that amphetamine abuse is responsible for 0.2% of AMIs in the state of Texas. The geographical distribution of amphetamine abuse varied by region, with the prevalence being highest in the North Texas and Panhandle regions of Texas.

CONCLUSIONS

This modest, though statistically robust, association suggests that amphetamine abuse may play a role in AMI.

Phentolamine therapy for cocaine-association acute coronary syndrome (CAACS)

INTRODUCTION

The emergency department (ED) evaluation of cocaine-associated acute coronary syndrome (CAACS) is often a diagnostic and therapeutic challenge.

CASE REPORT

We are reporting on the treatment of a patient with cocaine-associated acute coronary syndrome (CAACS) who did not benefit from standard therapy, but who eventually responded positively to phentolamine, an alpha-adrenergic receptor antagonist.

DISCUSSION

This report should encourage physicians to add phentolamine to their pharmacotherapeutic armamentarium in the treatment of CAACS.

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.

Deaths in the Cook County jail: 10-year report, 1995-2004

The aims of this study were to describe causes of death during the 10-year period between 1995 and 2004 in a large urban jail in Chicago; to compare disease specific mortality rates between the jail population and the general population; to explore demographic and incarceration characteristics of the inmates who died in the jail by cause of death; and to examine gender difference in demographic characteristics, incarceration patterns, and causes of death. A total of 178 deaths occurring in the jail over a 10-year period (1995-2004) were reviewed. Age-adjusted disease-specific mortality rates were computed for the jail population and compared with the rates in the US general population. Cause of death, demographic variables, and incarceration related factors were retrieved from multiple computerized databases. Descriptive analyses were performed to examine demographic and incarceration-related patterns by cause of death and gender. Heart disease was the most frequent cause of death in the jail population, followed by cerebrovascular disease and suicide. Mortality rates for heart diseases, infectious/inflammatory conditions and suicide were higher for jail inmates than the general population. Black inmates accounted for the majority of deaths due to illnesses and homicide, and a much higher proportion of white and Hispanic inmates were involved in suicide deaths. Deaths due to drug overdose or withdrawal were disproportionately higher among female inmates compared with male inmates. Consistent review of mortality rates and causes of deaths in jail can be a useful tool to better understand health issues and needs of jail inmates. Surveillance of acute and chronic illnesses and strategic reengineering of jail health care is a key to quality improvement for incarcerated populations for whom the jail system becomes their primary care provider.

Anaesthesia for pituitary surgery

The anaesthetic care of patients undergoing pituitary surgery involves an understanding of the varied presentations of pituitary disease and their implications for the patient's perioperative condition and management. The neuroanaesthetist must also have an appreciation of the issues relevant to the surgical approach (either transsphenoidal or, less commonly, transcranial) and be able to anticipate and manage them accordingly.

Selenium diet-supplementation improves cocaine-induced myocardial oxidative stress and prevents cardiac dysfunction in rats

Chronic cocaine abuse causes cardiac dysfunction and induces oxidative stress. The goal of this study was to evaluate whether an enhanced antioxidant pool, induced by the administration of selenium, may prevent the myocardial dysfunction induced by cocaine. Cocaine was administered for 7 days (15 mg/kg/day, i.p.) to rats pretreated for 4 weeks with selenium (1.16 mg/L/day, p.o.). Cardiac function was evaluated by cardiac index and left ventricular (LV) fractional shortening (FS) measured by echocardiography. The redox ratio and enzymatic activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD) were measured in the LV myocardium. Cocaine administration induced a cardiac dysfunction, as evidenced by a decrease in cardiac index and LV FS as well as by an increase in LV diameters. Moreover, antioxidant markers and redox ratio were altered in rats after cocaine exposure. Selenite supplementation induced a significant limitation of cardiac index and FS alterations observed after cocaine administration. This improvement in cardiac function was associated with a redox ratio recovery while SOD and GPX activities remained unchanged. Thus, selenite reversed both the oxidative stress and the contractile dysfunction induced by cocaine administration. These results suggest a major role of oxidative stress in the cocaine-induced cardiotoxicity.

Prenatal cocaine administration increases glutathione and alpha-tocopherol oxidation in fetal rat brain

Recent findings suggest that prenatal cocaine exposure results in significant attenuation of uterine and placental blood flow. The extent of blood flow reduction to fetuses positively correlates with reductions in glial-derived neurotrophic factor (GDNF) and dopamine (DA). However, whether such changes in uterine blood flow are sufficient to induce oxidative stress have yet to be determined. In the following experiments, the impact of prenatal cocaine exposure on fetal brain levels of the endogenous antioxidant glutathione (GSH and its oxidized form GSSG) or the exogenous antioxidant alpha-tocopherol (alpha-T and its oxidized quinone form) was investigated. It was hypothesized that cocaine exposure would result in greater oxidation of both GSH and alpha-T. Results indicated that a single injection of cocaine to a drug-naive pregnant dam results in significant (-16.38%) reductions in the levels of GSH. GSSG can be either raised or reduced as a result of fetal uterine position: fetuses at the ovarian extremes show significant increases in GSSG in response to cocaine (+64.73%), whereas cervically situated fetuses show decreased GSSG (-47.91%). Additionally, cocaine significantly decreased the levels of alpha-T (-15.9%) and increased the levels of its oxidative product alpha-Tquinone (alpha-Tq, +34.05%). Levels of alpha-T were not affected by fetal uterine position. These data collectively suggest that cocaine exposure increases the utilization of both endogenous and exogenous anti-oxidants in the fetal rat brain. Along with previous studies, these data support the hypothesis that cocaine-induced vasoconstriction results in oxidative stress in the gestating fetus.

The pathophysiology of cocaine abuse

Cocaine is a naturally occurring alkaloid that increases dopamine concentrations in the reward centers of the brain. There has been a marked increase in cocaine abuse over the last two decades. A neuropsychological stimulant, cocaine also reduces somnolence, increases alertness and improves concentration. However, cocaine abuse has many pathophysiological consequences. These fall broadly into four groups: pathology associated with a drug abusing lifestyle, pathology that occurs whilst intoxicated with (but not directly due to) the drug, pathology associated with drug administration and pathology resulting from pharmacological action of the drug. This review provides a detailed description of the physiological, pharmacological, and pathological effects of cocaine, and highlights the forensic and medicolegal implications of cocaine abuse.

Prenatal cocaine exposure induces an attenuation of uterine blood flow in the rat

We have previously demonstrated that maternal cocaine injections result in a gradient of fetal brain cocaine levels that decrease as a function of the fetuses' proximity to the ovaries at embryonic (E) day 15. Our prior data suggest that cocaine-induced vasoconstriction may (1) limit cocaine's entry into the brain and (2) cause damage to DA neurons through injury associated with hypoxia or ischemia of the utero-placental junction. Therefore, using the microsphere technique (labeled with Ru(103)), the following study sought to determine whether the previously observed pattern of cocaine distribution among fetuses in the uterus were due to position-specific reductions in uterine or placental blood flow. On day 15, a single subcutaneous injection of 30 mg/kg cocaine HCl was administered to each rat. Thirty minutes after the cocaine injection, reference blood samples were drawn from the ventral tail artery. Uterine segments and placentae were removed and subjected to gamma counting. While results regarding placental blood flow were equivocal, cocaine significantly reduced average uterine blood flow by 54.6%. In addition, as one moves more proximal to the ovaries, cocaine progressively attenuates blood flow in uterine tissue segments. These data support the hypothesis that the pattern of drug distribution and subsequent brain alterations from prenatal cocaine exposure in our previous reports are likely due to differences in uterine blood flow.

Effects of cocaine and cocaine metabolites on cardiovascular function in squirrel monkeys

The effects of cocaine and the cocaine metabolites norcocaine, ecgonine methyl ester, benzoylecgonine and cocaethylene were evaluated in conscious squirrel monkeys for their effects on blood pressure and heart rate. Norcocaine, ecgonine methyl ester and benzoylecgonine are produced in vivo following cocaine use. Cocaethylene is produced in vivo following concurrent cocaine and alcohol use. Increases in both blood pressure and heart rate were observed following cocaine doses of 0.3-3.0 mg/kg. Ecgonine methyl ester and benzoylecgonine had no effect on either parameter up to doses of 10.0 mg/kg. Norcocaine increased blood pressure, but was less potent than cocaine. Norcocaine did not affect heart rate at doses up to 3.0 mg/kg. In contrast to the other metabolites, cocaethylene increased blood pressure and heart rate similarly to cocaine. These results suggest that ecgonine methyl ester and benzoylecgonine are devoid of cardiovascular effects at doses comparable to cocaine and would not be expected to contribute to cocaine's overall cardiovascular effects. Norcocaine's effect on blood pressure might contribute to the cardiovascular effects of cocaine, but this metabolite is produced only at low levels in vivo. The one metabolite that might be expected to contribute to cocaine's overall cardiovascular effect is cocaethylene, although the degree of this contribution is not clear.

Cocaine induced myocardial infarction

The case of a 29 year old man who presented with chest pains after the use of cocaine is reported. The diagnosis of myocardial infarction was made on the electrocardiogram changes and lactate dehydrogenase profile. The diagnosis may be overlooked if there is no direct questioning about the use of drugs such as cocaine. Diazepam has an important role in the management of cardiac complications after cocaine use and should be used early in management. The use of thrombolysis should be a joint decision between the emergency physician and cardiologist.

Prolonged QT interval and cocaine use

Cardiovascular consequences of cocaine use are well known, and surveillance for them is common practice in the routine care of cocaine abusers. However, the cardiac electrical abnormalities that arise, although studied in animal experiments, lack correlation with human reports. The case of a 17-year-old girl, who was admitted after a cocaine binge is reported. She was cardiologically asymptomatic, but an admission electrocardiogram was abnormal, with QT interval prolongation. This returned to normal within 24 hours of observation. The literature on the electrophysiologic effects of cocaine on the heart is reviewed.