Subacute Endocarditis: Understanding Its Clinical Manifestations

Subacute endocarditis is a serious infection that affects the inner lining of the heart chambers and valves. Its clinical presentation can vary widely, but generally falls into three main categories: systemic symptoms, cardiac-related manifestations, and extracardiac complications.

Systemic Symptoms of Subacute Endocarditis

Fever is one of the hallmark signs of subacute endocarditis. Unlike acute infections, the fever pattern in this condition can be irregular, presenting as remittent fever, intermittent fever, or even low-grade fever. Patients may also experience fatigue, weight loss, night sweats, and general malaise, which are common in chronic infectious processes.

Cardiac Manifestations

During a physical examination, a physician may detect a new or changing heart murmur, which results from damage to the heart valves caused by the infection. These murmurs are often indicative of valvular dysfunction. In addition to auscultation findings, electrocardiographic (ECG) abnormalities may reveal arrhythmias, which can vary in type and severity. Echocardiography is a critical diagnostic tool in these cases, as it can visualize intracardiac vegetations—clumps of bacteria, fibrin, and inflammatory debris attached to the heart valves or endocardium.

Extracardiac Complications

One of the most dangerous aspects of subacute endocarditis is its potential to cause embolic events. Infected material from the heart can dislodge and travel through the bloodstream, leading to complications in distant organs. When these emboli reach the brain, they can cause encephalitis, cerebral hemorrhage, or ischemic stroke. Other systemic effects may include peripheral vascular damage, such as Janeway lesions or Osler's nodes, which are visible signs on the skin and extremities.

Conclusion

Recognizing the diverse clinical signs of subacute endocarditis is crucial for early diagnosis and treatment. Due to its potentially life-threatening complications, any combination of unexplained fever, heart murmur changes, and embolic events should prompt further investigation. Timely intervention with appropriate antimicrobial therapy and, in some cases, surgical management, can significantly improve patient outcomes.