Serial angiography in cocaine-induced myocardial infarction

Treatment of cocaine cardiovascular toxicity: a systematic review

INTRODUCTION

Cocaine abuse is a major worldwide health problem. Patients with acute cocaine toxicity presenting to the emergency department may require urgent treatment for tachycardia, dysrhythmia, hypertension, and coronary vasospasm, leading to pathological sequelae such as acute coronary syndrome, stroke, and death.

OBJECTIVE

The objective of this study is to review the current evidence for pharmacological treatment of cardiovascular toxicity resulting from cocaine abuse.

METHODS

MEDLINE, PsycINFO, Database of Abstracts of Reviews of Effects (DARE), OpenGrey, Google Scholar, and the Cochrane Library were searched from inception to November 2015. Articles on pharmacological treatment involving human subjects and cocaine were selected and reviewed. Evidence was graded using Oxford Centre for Evidence-Based Medicine guidelines. Treatment recommendations were compared to current American College of Cardiology/American Heart Association guidelines. Special attention was given to adverse drug events or treatment failure. The search resulted in 2376 articles with 120 eligible involving 2358 human subjects. Benzodiazepines and other GABA-active agents: There were five high-quality (CEBM Level I/II) studies, three retrospective (Level III), and 25 case series/reports (Level IV/V) supporting the use of benzodiazepines and other GABA-active agents in 234 subjects with eight treatment failures. Benzodiazepines may not always effectively mitigate tachycardia, hypertension, and vasospasm from cocaine toxicity. Calcium channel blockers: There were seven Level I/II, one Level III, and seven Level IV/V studies involving 107 subjects and one treatment failure. Calcium channel blockers may decrease hypertension and coronary vasospasm, but not necessarily tachycardia. Nitric oxide-mediated vasodilators: There were six Level I/II, one Level III, and 25 Level IV/V studies conducted in 246 subjects with 11 treatment failures and two adverse drug events. Nitroglycerin may lead to severe hypotension and reflex tachycardia. Alpha-adrenoceptor blocking drugs: There were two Level I studies and three case reports. Alpha-1 blockers may improve hypertension and vasospasm, but not tachycardia, although evidence is limited. Alpha-2-adrenoceptor agonists: There were two high-quality studies and one case report detailing the successful use of dexmedetomidine. Beta-blockers and β/α-blockers: There were nine Level I/II, seven Level III, and 34 Level IV/V studies of β-blockers, with 1744 subjects, seven adverse drug events, and three treatment failures. No adverse events were reported for use of combined β/α-blockers such as labetalol and carvedilol, which were effective in attenuating both hypertension and tachycardia. Antipsychotics: Seven Level I/II studies, three Level III studies, and seven Level IV/V case series and reports involving 168 subjects have been published. Antipsychotics may improve agitation and psychosis, but with inconsistent reduction in tachycardia and hypertension and risk of extrapyramidal adverse effects. Other agents: There was only one high level study of morphine, which reversed cocaine-induced coronary vasoconstriction but increased heart rate. Other agents reviewed included lidocaine, sodium bicarbonate, amiodarone, procainamide, propofol, intravenous lipid emulsion, propofol, and ketamine.

CONCLUSIONS

High-quality evidence for pharmacological treatment of cocaine cardiovascular toxicity is limited but can guide acute management of associated tachycardia, dysrhythmia, hypertension, and coronary vasospasm. Future randomized prospective trials are needed to evaluate new agents and further define optimal treatment of cocaine-toxic patients.

Cocaine-induced acute myocardial infarction

Acute myocardial infarction may occur following cocaine use. Cocaine-induced infarction is particularly common in younger patients aged 18 to 45 years old. Patients may or may not have angiographic evidence of coronary artery disease at the time of their acute event. Previous studies have shown that coronary artery spasm occurs with cocaine use, and perhaps platelet activation, both contributing to a process that may culminate in coronary artery occlusion. Primary coronary intervention should be the preferred revascularization modality by an experienced team. Thrombolytic therapy needs to be instituted if this intervention is unavailable. Beta blockers should be utilized with caution since they may increase coronary spasm or cause a paradoxical rise in blood pressure. They should be avoided in the early hours of the infarction, but be instituted prior to patient discharge. Interruption of cocaine abuse is the cornerstone of secondary prevention in cocaine-related myocardial infarction.

Les complications cardiovasculaires aiguës de la cocaïne. À propos de deux observations

Concerning any socioprofessional category, some addictive drugs like cocaine are responsible for many complications. The authors relate two case reports of young patients who suffered from cardiovascular accidents due to this drug. The first one was diagnosed with an ischemic stroke caused by carotid artery dissection and a leg distal vascular obliteration, the second one with a myocardial infarction with transient left ventricular dysfunction. Through these two case reports, the authors take stock of the pathophysiological and therapeutic knowledge of cardiovascular accidents after cocaine intake.

Trauma associated with acute myocardial infarction in a multi-state hospitalized population

INTRODUCTION

Trauma has been suggested, in case series, as one of the nonatherosclerotic mechanisms leading to acute myocardial infarction (AMI), the leading cause of death in the US. AMI following non-penetrating injury has been shown to carry significant morbidity and mortality.

OBJECTIVE

To determine whether hospitalized injuries in a large multi state population are associated with increased risk of AMI during the initial hospital stay.

METHODS

Statewide injury hospital discharge data were collected from 19 states in 1997. Affected body regions of interest included thoracic, abdominal or pelvic, spine or back and blunt cardiac injury (BCI). The outcome of interest was AMI which was identified based on ICD-9-CM discharge diagnoses for the same visit. Unadjusted and adjusted multivariate logistic regression analyses were performed.

RESULTS

Independent of confounding factors and coronary arteriography (CA) status, BCI was associated with 2.6-fold increased risk for AMI in persons 46 years or older. When the diagnosis of AMI was confirmed by CA, BCI was associated with 8-fold risk elevation among patients 46 years and older and a 31-fold elevation among patients 45 years and younger. Abdominal or pelvic trauma, irrespective of confounding factors and CA status, was associated with a 65% increase in the risk of AMI among patients 45 years and younger and 93% increase in the risk of among patients 46 years and older. When the diagnosis of AMI was confirmed by CA, abdominal or pelvic trauma was associated with 6-fold risk elevation among patients 46 years and older.

CONCLUSION

Direct trauma to the heart, as characterized by a diagnosis of BCI, was observed to carry the greatest risk for AMI. Abdominal or pelvic trauma also increased the risk for AMI. Longitudinal studies are warranted to better understand the relationship between trauma and AMI.

Increased prevalence of coronary artery aneurysms among cocaine users

BACKGROUND

Cocaine abuse has been implicated in multiple cardiovascular complications. Coronary artery aneurysms (CAAs) and ectasia occur in 0.2% to 5.3% of patients referred for angiography and are associated with atherosclerosis, Kawasaki's disease, and several rare disorders. After observing CAAs in multiple young cocaine users, we investigated the prevalence of CAAs among cocaine users undergoing coronary angiography.

METHODS AND RESULTS

Clinical and angiographic characteristics of 112 consecutive patients with a history of cocaine use and coronary angiography were compared with a control group of similar age and risk factors from an existing angiographic database over the same time period. Coronary angiograms were independently read by 3 reviewers blinded to cocaine use. Cocaine users were young (mean age, 44 years), predominantly male (80%), and cigarette smokers (95%). Control patients had higher rates of diabetes (33%) and more severe coronary artery disease (P=0.01). Previous myocardial infarction was common in both groups (45% of cocaine users, 38% of control patients). Despite the frequent history of myocardial infarction among cocaine users, 48% had nonobstructive coronary artery disease. Among cocaine users, 34 of 112 (30.4%) had CAAs compared with 6 of 79 (7.6%) in the control group (P<0.001). Cocaine use was a strong predictor of CAA by univariate and multivariate analyses.

CONCLUSIONS

This is the first description of an association between cocaine use and CAA. The prevalence of CAA among cocaine users was higher than expected (30.4%), given such a young cohort. Cocaine use may predispose to the formation of CAA, which may in turn be a contributing factor to myocardial infarction.

Terlipressin-Related Acute Myocardial Infarction: A Case Report and Literature Review

Acute ST-segment elevation myocardial infarction after the administration of terlipressin in patients with hemorrhagic esophageal varices is a rare but life-threatening complication. We report the case of a 73-year-old female patient with esophageal variceal bleeding complicated with acute ST-segment elevation myocardial infarction after intravenous injection of terlipressin. We discuss the underlying mechanisms of terlipressin-related acute myocardial infarction and review the literature.

Toxicity of local anaesthetics

The complications of failure, neural injury and local anaesthetic toxicity are common to all regional anaesthetic techniques, and individual techniques are associated with specific complications. All potential candidates for regional anaesthesia should be thoroughly evaluated and informed of potential complications. Central neural blockades still account for more than 70% of regional anaesthesia procedures. Permanent neurological injury is 0.02-0.07%. Pain on injection and paraesthesias while performing regional anaesthesia are danger signals of potential injury and must not be ignored. The incidence of systemic toxicity to local anaesthetics has significantly decreased in the past 30 years, from 0.2 to 0.01%. Peripheral nerve blocks are associated with the highest incidence of systemic toxicity (7.5 per 10,000) and the lowest incidence of serious neural injury (1.9 per 10,000).

Cocaine-associated chest pain: how common is myocardial infarction?

OBJECTIVE

Prior studies addressing the incidence of acute myocardial infarction (AMI) in patients with cocaine-associated chest pain have found divergent results. Previous prospective studies, which found approximately a 6% incidence of AMI, have been criticized for selection bias. This study sought to determine the rate of AMI in patients with cocaine-associated chest pain.

METHODS

All patients seen in an urban university-affiliated hospital between July 1996 and February 1998 were identified by ICD-9 medical records search for cocaine use and chest pain/ acute coronary syndromes. In this system, all faculty admit all patients with cocaine-associated chest pain for at least 23-hour observation periods. Data collected included demographics, medical and cocaine use history, presenting characteristics, hospital course, cardiovascular complications, and diagnostic tests using a 119-item closed-question data instrument with high interrater reliability. The main outcome measure was AMI according to World Health Organization (WHO) criteria.

RESULTS

There were 250 patients identified with a mean age of 33.5 +/- 8.5 years; 77% were male; 84% were African American. Of 196 patients tested, 185 had cocaine or cocaine metabolites in the urine (94%). The incidence of cardiac risk factors were: hypercholesterolemia, 8%; diabetes, 6%; family history, 34%; hypertension, 26%; tobacco use, 77%; prior MI, 6%; and prior chest pain, 40%. Seventy-seven percent admitted to cocaine use in the preceding 24 hours: crack, 85%; IV, 2%; nasal, 6%. Twenty-five patients (10%) had electrocardiographic evidence of ischemia. A total of 15 patients experienced an AMI (6%; 95% CI = 4.1% to 8.9%) using WHO criteria. Complications were infrequent: bradydysrrhythmias, 0.4%; congestive heart failure, 0.4%; supraventricular tachycardia, 1.2%; sustained ventricular tachycardia, 0.8%.

CONCLUSION

The incidence of AMI was 6% in patients with cocaine-associated chest pain. This result is identical to that found in prior prospective studies.

Characteristics and prognosis of myocardial infarction in patients with normal coronary arteries

STUDY OBJECTIVES

Myocardial infarction with angiographically normal coronary arteries (MINC) is a life-threatening event with many open questions for physicians and patients. There are little data concerning the prognosis for patients with MINC.

DESIGN

Retrospective follow-up study.

SETTING

Tertiary referral center.

PATIENTS

Patients with MINC were investigated and compared to age- and sex-matched control subjects with myocardial infarction due to coronary artery disease (CAD). The patients were examined clinically using stress exercise and hyperventilation tests. Migraine and Raynaud's symptoms were determined by means of a standardized questionnaire. Serum lipoproteins; the seroprevalence of cytomegalovirus, Helicobacter pylori, and Chlamydia pneumoniae infections; and the most frequent causes of thrombophilia were assessed.

MEASUREMENTS AND RESULTS

From > 4,300 angiographies that were performed between 1989 and 1996, 21 patients with MINC were identified. The mean +/- SD patient age at the time of myocardial infarction was 42 +/- 7.5 years. When compared to control subjects (n = 21), patients with MINC had fewer risk factors for CAD. In contrast, MINC patients had more frequent febrile reactions prior to myocardial infarction (six patients vs zero patients; p < 0.05), and the migraine score was significantly higher (7.1 +/- 6.3 vs 2.2 +/- 4.1; p < 0.01). The seroprevalence of antibodies against cytomegalovirus, C pneumoniae, and H pylori tended to be higher in patients with MINC and CAD as compared to matched healthy control subjects. Three patients with MINC vs none with CAD had coagulopathy. During follow-up (53 +/- 37 months), no major cardiac event occurred in the MINC group; no patients with MINC vs nine with CAD (p = 0.0001) underwent repeated angiography.

CONCLUSION

High migraine score and prior febrile infection together with a lower cardiovascular risk profile are compatible with an inflammatory and a vasomotor component in the pathophysiology of the acute coronary event in MINC patients. The prognosis for these patients is excellent.

Triggering of myocardial infarction by cocaine

BACKGROUND

Cocaine has been implicated as a trigger of acute myocardial infarction in patients with and those without underlying coronary atherosclerosis. However, the magnitude of the increase in risk of acute myocardial infarction immediately after cocaine use remains unknown.

METHODS AND RESULTS

In the Determinants of Myocardial Infarction Onset Study, we interviewed 3946 patients (1282 women) with acute myocardial infarction an average of 4 days after infarction onset. Data were collected on the use of cocaine and other potential triggers of myocardial infarction. We compared the reported use of cocaine in the hour preceding the onset of myocardial infarction symptoms with its expected frequency by using self-matched control data based on the case-crossover study design. Of the 3946 patients interviewed, 38 (1%) reported cocaine use in the prior year and 9 reported use within the 60 minutes preceding the onset of infarction symptoms. Compared with nonusers, cocaine users were more likely to be male (87% vs 67%, P=0.01), current cigarette smokers (84% vs 32%, P<0.001), younger (44+/-8 vs 61+/-13 years, P<0.001), and minority group members (63% vs 11%, P<0.001). The risk of myocardial infarction onset was elevated 23.7 times over baseline (95% CI 8.5 to 66.3) in the 60 minutes after cocaine use. The elevated risk rapidly decreased thereafter.

CONCLUSIONS

Cocaine use is associated with a large abrupt and transient increase in the risk of acute myocardial infarction in patients who are otherwise at relatively low risk. This finding suggests that studying the pathophysiological changes produced by cocaine may provide insights into the mechanisms by which myocardial infarction is triggered by other stressors.

The evaluation of cocaine-induced chest pain with acute myocardial perfusion imaging

OBJECTIVE

To use myocardial perfusion imaging to determine the etiology of cocaine-induced chest pain in patients without ECG evidence of acute cardiac ischemia.

METHODS

The authors conducted a prospective study of consecutive consenting patients aged 18-70 years with cocaine-induced chest pain who reported cocaine use within three days and presented with a chief complaint of chest pain occurring within three hours and lasting longer than 15 minutes with a normal or nondiagnostic ECG. Patients were excluded if they had a clear-cut noncardiac cause of chest pain, ECG evidence of acute cardiac ischemia, history of myocardial infarction, pregnancy, or lactation, required immediate hospitalization, or were unable to consent. Patients were injected with Tc-99m tetrofosmin and imaged. Perfusion scans were independently read by two nuclear radiologists. Clinicians blinded to scan results determined patient disposition. Patients with abnormal scans were asked to return for follow-up resting scans.

RESULTS

Fourteen patients were enrolled. Twelve of the 14 patients had chest pain at the time of Tc-99m tetrofosmin injection. Ten of the 14 [(71%) 95% CI = 48% to 95%] scans were normal or within normal limits. Four of the 14 [(29%) 95% CI = 5% to 52%] were abnormal. Of the four patients with abnormal scans, two had follow-up scans that demonstrated an irreversible perfusion abnormality, and two who did not return for follow-up reported no subsequent hospitalizations for acute cardiac ischemia.

CONCLUSION

Perfusion imaging did not demonstrate reversible ischemia in most patients (12/14, 86%) with cocaine-induced chest pain without ECG evidence of ischemia. These results suggest that cocaine-induced chest pain in most patients without ECG evidence of ischemia is not due to acute ischemia.