ECG

ECG in Coronary Artery Disease | On-demand

Coronary Artery Disease is the most common acquired disease of modern era. Depending on the severity of ischaemia, coronary artery disease it can present as- ECG is an important, easily available and reliable tool for diagnosing and planning treatment of a patient with CAD. However, clinical judgement other investigations are often required to confirm the diagnosis because ECG may not reflect the actual severity of ischaemia and underlying damage. ECG can be normal in 1-6% of patients with Acute Coronary Syndrome, so, it becomes important to repeat the ECG at regular intervals in such cases. Repeating the ECG may reveal … Read more

Failure to Capture in Pacemakers and ICD

Definition: Failure to capture means when the pacemaker initiates a stimulus, but it fails to depolarise the myocardium. It is depicted on ECG by the presence of spikes of pacemaker but there is no associated depolarisation of the concerned chamber. Causes of failure to capture are: This ECG shows: Cause: Intermittent Failure to Capture. If we carefully see lead V1, we can see progressive widening of QRS. But, at the same time we can see that P waves are preceded by QRS complex every time. What could be the reason? This is rate-dependent widening of QRS also known as use-dependent … Read more

ECG in Hypocalcemia

Hypocalcemia is defined as a calcium level below the normal range. The normal serum calcium level varies from 8.5 to 10.5 mg/dL and the normal level of ionized calcium is 4.2 to 4.8 mg/dL.

ECG in Hypercalcemia

Overview of Hypercalcemia Hypercalcemia refers to the presence of elevated calcium level above normal. The normal level of total serum calcium varies from 8.5 to 10.5 mg/dL or for ionized calcium 4.2 to 4.8 mg/dL. When extracellular calcium is increased, the duration of the action potential is shortened. Shortening of the action potential duration results in shortening of the QT interval. The ECG findings of hypercalcemia include (Figs. 1 and 2): Shortening of the QT interval. This is due to shortening of phase 2 of the action potential corresponding to the ST segment in the ECG. Elevation of the ST … Read more

ECG in Hypokalemia

Overview of Hypokalemia Hypokalemia is defined as the presence of serum potassium that is lower than normal. The normal value for serum potassium is 3.3 to 5.3 mmol/L. The most important ECG finding in hypokalemia is the presence of prominent U waves. As the hypokalemia becomes more profound, the amplitude of the T wave becomes lower as the size of the U wave becomes larger until both T and U waves bond together and become indistinguishable (Figs. 1 and 2). Normal U wave: The U wave follows the T wave and is the last component of ventricular repolarization. The normal … Read more