The ECG provides important information about the electrical activity of the heart. Abnormalities can interfere with the ability of the heart to pump blood effectively, which is needed for tissue oxygenation. Normally, the SA node has the greatest degree of automaticity and therefore paces the heart. The AV node serves as the backup pacemaker in case the SA node fails. Many different arrhythmias can occur in the heart and interfere with cardiac function. One of the most important abnormalities to watch for is the elevation of the ST segment; this indicates myocardial ischemia and may be life threatening. Chronic lung disease also has the ability to alter the electrical activity of the heart, with right axis deviation being most common among patients with right heart failure because of chronic hypoxemia.
The ECG provides important information about the electrical activity of the heart. Abnormalities can interfere with the ability of the heart to pump blood effectively, which is needed for tissue oxygenation. Normally, the SA node has the greatest degree of…