Chronic low-grade inflammation as demonstrated by increased monocyte count and elevation of serum high-sensitive C-reactive protein levels is associated with CAS. However, other than smoking, classic atherosclerotic risk factors were poorly associated with CAS in a study of Japanese patients. CAS is reported to occur in 1%-5% of coronary angiography cases. Ethnic differences in the frequency of CAS are noted, with CAS being more frequent in Japanese patients (a 3-fold greater incidence of spasm) than Caucasian patients. Traditionally, female patients are felt to be much more likely to develop coronary spasm, although recent observations suggest a male preponderance.
Patients with CAS typically describe classic angina symptoms, such as chest pain with radiation to the arm, shoulder, neck, and jaw. Transient ST-segment elevation during episodes of chest pain that resolves completely within minutes is a pathognomonic finding in patients with variant angina. Some episodes of CAS are brief and may be asymptomatic. Severe vasospastic angina may result in potentially fatal ventricular arrhythmias with hemodynamic deterioration and syncope. Other causes of cardiac arrest, such as myocardial infarction, long-QT syndrome, and hypertrophic obstructive cardiomyopathy, must be excluded by assessment of cardiac biomarkers, electrocardiography, and echocardiography. Cocaine and certain other drug use, which can also cause coronary vasospasm, must be ruled out.
Patients with CAS presenting with symptoms or signs of acute myocardial ischemia require admission. A 12-lead ECG and continuous telemetry monitoring are critical in the initial evaluation of patients presenting with chest pain concerning for acute coronary syndromes. Serial measurements of cardiac enzymes and troponin levels should be performed to assess for evidence of ischemia. Other laboratory tests should include a complete blood count, serum chemistry, and lipid profile. Urine toxicology to assess for recent cocaine use can be helpful, but it does not absolutely rule out cocaine-induced vasospasm because spasm can continue to occur even weeks after usage, at which time the urine screening may be negative.
Transthoracic echocardiography can rule out structural heart disease as well as other causes of symptoms, including pericarditis, valvular disease, or abnormalities of the aorta. Stress testing with myocardial perfusion imaging or coronary angiography is essential to assess coexisting or contributory atherosclerotic coronary disease. Because transient ST-segment elevation during episodes of chest pain that resolves completely within minutes is a characteristic finding in patients with variant angina, a 12-lead ECG is essential to diagnose CAS. Holter monitoring may facilitate the diagnosis of silent CAS as well as the detection of life-threatening arrhythmias (ventricular fibrillation, ventricular tachycardia, and complete atrioventricular block).
Coronary angiography with provocative testing (using acetylcholine, ergonovine, or methylergonovine) is the criterion standard for diagnosis. Angiography may reveal minimal or no angiographic evidence of coronary artery disease. Variant angina is the most likely diagnosis in relatively young patients without angiographic evidence of coronary artery disease.
Medscape © 2022 WebMD, LLC
Cite this: Cardio Case Challenge: Syncope in a 53-Year-Old Woman With Dyspnea and Morning Chest Pain - Medscape - Apr 18, 2022.