From the Guidelines
Patients with endocarditis can exhibit several EKG changes, including sinus tachycardia, heart block, new bundle branch blocks, nonspecific ST-segment and T-wave changes, atrial fibrillation, and localized ST-segment elevation in cases of myocardial abscess formation. These EKG changes are not specific to endocarditis and must be interpreted alongside clinical findings, blood cultures, and echocardiography results for proper diagnosis and management. The most common EKG finding is sinus tachycardia, which reflects the body's response to infection and inflammation 1. Heart block, particularly first-degree AV block, may develop when infection involves the conduction system, especially in cases of aortic valve endocarditis with extension into the interventricular septum 1. New bundle branch blocks can occur for similar reasons. Patients may also show nonspecific ST-segment and T-wave changes due to myocardial inflammation or ischemia from septic emboli. Atrial fibrillation or other arrhythmias may develop, particularly in patients with pre-existing cardiac disease or when endocarditis causes significant valvular dysfunction leading to chamber enlargement.
Some key points to consider in the diagnosis and management of endocarditis include:
- The use of echocardiography, including transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE), to evaluate valve function and morphology, and to detect complications such as abscesses or pseudoaneurysms 1.
- The importance of clinical findings, such as new heart murmurs, signs of heart failure, or embolic events, in diagnosing and managing endocarditis 1.
- The role of blood cultures in diagnosing endocarditis, and the need for prompt antibiotic therapy in patients with suspected or confirmed endocarditis 1.
- The potential for EKG changes to occur in endocarditis, and the need to interpret these changes in the context of clinical findings and other diagnostic tests 1.
Overall, the diagnosis and management of endocarditis require a comprehensive approach that takes into account clinical findings, laboratory results, and imaging studies, including EKG and echocardiography.
From the Research
EKG Changes in Endocarditis
EKG changes can occur in patients with endocarditis, and these changes can be associated with increased mortality and invasive infection 2. The following are some of the EKG changes that can occur in endocarditis:
- Cardiac conduction abnormalities, such as bundle branch block, atrioventricular blocks grade I to III, and ectopic functional tachycardia 3
- ECG changes signalizing spread of the infection beyond the endocardium, such as myocardial infarction after embolization of the vegetation into the coronary artery 3
- Pericarditis with diffuse ST-T elevations on the ECG tracing 3
- Heart block, which can be a sign of myocardial abscess formation and may require surgical intervention 4
- Atrioventricular block, which can be complete or incomplete and may require antibiotic therapy or surgical intervention 4, 5
Association with Mortality and Invasive Infection
ECG conduction changes are associated with increased mortality and invasive infection in patients with endocarditis 2. In one study, 11 of 36 (31%) patients with ECG conduction changes died during hospitalization, compared with 15 of 101 (15%) patients without changes (P = .039) 2. Additionally, 8 of 15 (53%) invasive infections exhibited ECG conduction changes, compared with 16 of 61 (26%) isolated valve infections (P = .046) 2.
Importance of EKG in Endocarditis
The EKG plays an important role in the initial and ongoing evaluation of patients with suspected endocarditis 6. It can provide information on the origin and complications of possible organic disease, and regular follow-up of ECG tracings can reveal changes signalizing spread of the infection beyond the endocardium 3.