An electric shock occurs when current passes through the body, potentially damaging organs. When an electric shock causes death, it is termed electrocution. These incidents can seriously impact the heart, disrupting its natural electrical activity and causing injury.
Direct Cardiac Effects of Electrocution
Electric current can profoundly affect heart function, leading to immediate, life-threatening consequences. One dangerous effect is ventricular fibrillation (VFib), where the heart’s lower chambers quiver ineffectively instead of pumping blood. This disorganized electrical activity prevents blood circulation, making it the most common cause of death from electrocution, especially with alternating current (AC) exposure.
A high-current shock can cause asystole, a complete cessation of the heart’s electrical activity and pumping action, resulting in cardiac arrest. Beyond rhythm disturbances, electricity can directly damage heart muscle cells, leading to myocardial injury or necrosis. This cellular damage can cause inflammation or weakening of the heart muscle.
Arrhythmias, or irregular heart rhythms, can also occur, including fast heart rates (tachycardia), slow heart rates (bradycardia), or premature beats. Changes might be visible on an electrocardiogram (ECG), which records the heart’s electrical signals. ECG changes can range from non-specific alterations in ST segments and T-waves to more serious conduction abnormalities.
Factors Determining Severity of Cardiac Injury
Cardiac injury severity is influenced by several factors beyond voltage. The amount of current (amperage) is the primary determinant of injury severity, with higher currents causing more damage. While voltage drives the current, amperage directly impacts tissues.
The current’s pathway significantly affects risk to the heart. Current passing through the chest, such as hand to hand or hand to foot, is especially dangerous as it is more likely to traverse the heart. A longer duration of contact increases injury likelihood and severity.
The type of current also plays a role. Alternating current (AC) is generally more dangerous for the heart than direct current (DC). AC can induce sustained muscle contraction, making it difficult to release the source, and more readily causes ventricular fibrillation. DC often causes a single, forceful muscle contraction that may throw the person away.
The body’s resistance, mainly skin, also affects current flow. Dry skin has higher resistance, potentially leading to superficial burns, while wet or broken skin reduces resistance, allowing more current to penetrate deeper tissues and cause internal damage.
Immediate Steps and Medical Evaluation
Following an electrical shock, first disconnect the power source. For any significant shock or if symptoms are present, immediately call emergency services. Even minor shocks can have delayed cardiac effects, making prompt medical evaluation necessary.
Medical professionals will stabilize the individual and assess vital signs. An electrocardiogram (ECG) is often performed to check for abnormal heart rhythms or other cardiac changes. Blood tests, including cardiac enzymes, may detect heart muscle damage, similar to a heart attack diagnosis.
Depending on the shock’s nature and initial findings, hospital observation may be necessary. This allows monitoring for delayed cardiac issues, as some complications might not appear immediately. For low-voltage injuries without symptoms or ECG abnormalities, 4-6 hours of observation may suffice, while high-voltage exposures or symptomatic cases often require at least 24 hours.
Long-Term Heart Health Considerations
Even after an electrical injury, long-term heart health considerations exist. Some individuals may experience delayed arrhythmias, where irregular heart rhythms develop days or weeks after the incident. While less common, these issues can be serious.
Severe direct heart muscle damage from electrocution can lead to scarring or weakening. This scarring could affect the heart’s ability to pump blood effectively, possibly contributing to cardiomyopathy, a heart muscle disease. Though rare, long-term complications underscore the importance of thorough initial evaluation.
Follow-up appointments with a cardiologist are often advised after a significant shock to monitor heart health. This assessment helps detect subtle or evolving cardiac abnormalities not apparent initially. Regular check-ups ensure any lasting effects are identified and managed.