Elevated Cardiac Enzymes in Myocarditis Patients

Cardiac enzymes are substances found in heart muscle cells. When these cells become damaged, the enzymes are released into the bloodstream, leading to a noticeable increase in their levels. Elevated cardiac enzyme levels may indicate heart damage caused by conditions such as viral myocarditis or myocardial infarction. Therefore, it's crucial to monitor these levels for early detection of heart-related issues.

Types of Cardiac Enzymes

Cardiac enzymes include lactate dehydrogenase (LDH), aspartate aminotransferase (AST), creatine phosphokinase (CPK), and creatine phosphokinase isoenzyme (CK-MB), along with alanine aminotransferase (ALT). Among these, CK-MB has the highest specificity for heart tissue. It is commonly referred to as CK-MB in clinical settings and is primarily found in the heart muscle.

CK-MB and Myocardial Damage

During myocardial necrosis, CK-MB levels rise significantly. The normal reference range is 0–25 U/L. In patients with myocarditis, this value can be more than three times higher—typically above 75 U/L. Other cardiac enzymes may also show elevated levels, but CK-MB remains a key indicator due to its high specificity.

Role of Cardiac Troponin

However, when diagnosing myocarditis or myocardial necrosis, cardiac troponin is considered a more reliable marker. It has higher sensitivity and specificity, making it the preferred biomarker in clinical practice for detecting heart muscle damage.

Recognizing Symptoms of Myocarditis

Myocarditis often follows a recent viral infection. Most patients experience symptoms like colds, coughing, and sore throat approximately 2–3 weeks before the onset of myocarditis. If these initial symptoms are severe and left untreated, especially when combined with physical exhaustion and a weakened immune system, the infection may spread to the heart.

Common cardiac symptoms include rapid heartbeat, chest tightness, palpitations, and arrhythmias. In severe cases, myocarditis can even lead to sudden cardiac death. Early diagnosis and treatment are crucial to prevent complications and improve outcomes.

Diagnosis and Treatment

When a patient presents with elevated cardiac enzymes, further diagnostic tests and clinical evaluation are necessary to confirm the underlying cause. These may include imaging studies, electrocardiograms (ECGs), and blood tests for cardiac troponin.

Once diagnosed, treatment should be tailored to the individual's condition. A critical component of myocarditis management is complete rest, which helps reduce strain on the heart and supports recovery. Patients should also follow a light, nutritious diet and stay well-hydrated to aid in the healing process.