An electrocardiogram (EKG), also known as an ECG, evaluates the heart’s electrical activity. A stroke, however, involves an interruption of blood flow to the brain. While these are distinct medical events, many wonder if an EKG can detect a stroke.
What an EKG Measures
An EKG is a quick, non-invasive test that records the electrical signals of your heart. Electrodes are placed on your chest and sometimes on your limbs, connecting to an EKG machine. This machine measures and displays these electrical impulses as wavy lines.
The EKG provides information about your heart’s rate (how fast it beats) and its rhythm (whether beats are steady or irregular). It captures the sequence of electrical activation as it spreads through the heart’s chambers, from the atria to the ventricles. This electrical activity helps the heart’s four chambers contract in a coordinated rhythm to effectively pump blood throughout the body.
How Strokes Are Diagnosed
Diagnosing a stroke focuses on assessing the brain and identifying the cause of the disruption in blood flow. A neurological examination is a primary step, where healthcare providers assess a person’s awareness, speech, vision, and motor function to pinpoint affected brain areas. This initial assessment guides further diagnostic steps.
Brain imaging techniques are used to visualize the brain and determine the type of stroke. A Computed Tomography (CT) scan is often the first imaging test, quickly identifying if there is bleeding in the brain, which indicates a hemorrhagic stroke. Magnetic Resonance Imaging (MRI) provides more detailed images and can detect ischemic strokes, caused by blood clots, within minutes of onset. Blood tests may also be performed to check for clotting factors or other conditions that could mimic stroke symptoms.
Heart Conditions and Stroke Risk
While an EKG does not directly detect a stroke, it can identify heart conditions that increase stroke risk. The most notable example is Atrial Fibrillation (AFib), a common type of irregular heartbeat. In AFib, the heart’s upper chambers (atria) quiver chaotically instead of contracting effectively, leading to blood pooling.
This stagnant blood can form clots. These clots can dislodge, travel through the bloodstream, and if they reach the brain, block an artery, causing an ischemic stroke. An EKG can detect AFib by showing an irregular heart rhythm, identifying higher-risk individuals. Beyond AFib, an EKG can also reveal other conditions like left ventricular hypertrophy (enlargement of the heart’s main pumping chamber) or evidence of a previous heart attack, also associated with elevated stroke risk. Thus, the EKG assesses underlying cardiac conditions contributing to stroke risk, playing a role in preventative strategies rather than immediate stroke detection.