Cocaine-Induced Cardiovascular Disease

KEY FEATURES

ESSENTIALS OF DIAGNOSIS

• Chest pain, myocarditis-like syndrome, and myocardial infarction

• Features of congestive heart failure secondary to cocaine dilated cardiomyopathy

• Hypertension

• Positive history or urine drug screen for cocaine

• ECG is often nonspecific (non–Q-wave infarction is more common than Q-wave infarction in cocaine users)

GENERAL CONSIDERATIONS

• Cocaine is the most common illicit drug with major actions on the cardiovascular system

• Cocaine increases vasoactive and cardiac-stimulating substances, causing peripheral and coronary artery constriction, tachycardia, and increased cardiac contractility

• Myocardial ischemia and life-threatening ventricular arrhythmias may ensue

• Irreversible structural damage to the heart eventually occurs

• May accelerate existing atherosclerotic coronary artery disease

CLINICAL PRESENTATION

SYMPTOMS AND SIGNS

• Chest pain

• Dyspnea

• Syncope

PHYSICAL EXAM FINDINGS

• Hypertension

• Tachycardia

• Increased respiratory rate

DIFFERENTIAL DIAGNOSIS

• Atherosclerotic coronary artery disease

• Spontaneous coronary artery spasm

• Spontaneous coronary artery dissection

DIAGNOSTIC EVALUATION

LABORATORY TESTS

• Cocaine blood or urine screen

• Elevated cardiac biomarkers, such as troponin, brain natriuretic peptide

ELECTROCARDIOGRAPHY

• Nonspecific ST-T–wave changes

• Ischemic ST-T–wave changes

• Q-wave myocardial infarction less common

IMAGING STUDIES

• Echocardiography: may show segmental wall motion abnormalities and reduced left ventricular function

• Nuclear perfusion studies: may show patchy defects

DIAGNOSTIC PROCEDURES

• Coronary angiography may be needed to exclude coronary artery disease

TREATMENT

CARDIOLOGY REFERRAL

• Suspected myocardial ischemia/infarction

• Serious ventricular arrhythmias

• Cardiomyopathy present

HOSPITALIZATION CRITERIA

• Acute coronary syndromes

• Syncope or collapse

• Significant arrhythmias

• Severe hypertension

MEDICATIONS

• Nitrates, alpha-adrenoreceptor blockers, and verapamil for acute ischemia

• Aspirin

• Thrombolytic therapy in acute ST-segment elevation myocardial infarction

• Beta blockers are controversial, due to the fear of unopposed alpha stimulation, but clinical observations suggest they are well tolerated and can be useful

• Type Ia and III antiarrhythmics are relatively contraindicated

• Lidocaine should be used cautiously because it lowers the seizure threshold

THERAPEUTIC PROCEDURES

• Emergent coronary angiography and primary angioplasty may be used as alternative means of establishing perfusion

• Although often indicated, few get drug-eluting stents due to the uncertainty regarding whether they can commit to months of dual antiplatelet therapy

• These patients are rarely candidates for cardiac transplantation

MONITORING

• ECG monitoring in hospital as appropriate

DIET AND ACTIVITY

• Low-sodium, low-fat diet

• Restricted activities initially, then cardiac rehabilitation

ONGOING MANAGEMENT

HOSPITAL DISCHARGE CRITERIA