What effect does hypercalcemia have on the QRS complex?

What effect does hypercalcemia have on the QRS complex?

• A. It becomes narrow
• B. It becomes wide
• C. It remains unchanged
• D. It becomes biphasic

Answer: (B)

Hypercalcemia, which is an elevated level of calcium in the blood, can have a significant impact on the electrical conduction system of the heart, particularly manifesting as changes in the QRS complex on an electrocardiogram (ECG). When calcium levels rise, they can alter the excitability and conduction velocity of cardiac myocytes. Specifically, hypercalcemia tends to increase the speed of conduction through the heart, which can result in a wider QRS complex. This widening occurs because the elevated calcium levels can affect the duration of cardiac depolarization and delay repolarization of the ventricles. As a result, the time taken for the ventricles to contract and return to their resting state is prolonged, leading to a visually widened QRS complex on the ECG. Understanding the relationship between hypercalcemia and the QRS complex is crucial for interpreting ECGs in clinical practice. It helps in recognizing potential underlying pathological states and offers insight into the electrolytic balance of the patient being examined.

Hypercalcemia, which is an elevated level of calcium in the blood, can have a significant impact on the electrical conduction system of the heart, particularly manifesting as changes in the QRS complex on an electrocardiogram (ECG). When calcium levels rise, they can alter the excitability and conduction velocity of cardiac myocytes. Specifically, hypercalcemia tends to increase the speed of conduction through the heart, which can result in a wider QRS complex.

This widening occurs because the elevated calcium levels can affect the duration of cardiac depolarization and delay repolarization of the ventricles. As a result, the time taken for the ventricles to contract and return to their resting state is prolonged, leading to a visually widened QRS complex on the ECG.

Understanding the relationship between hypercalcemia and the QRS complex is crucial for interpreting ECGs in clinical practice. It helps in recognizing potential underlying pathological states and offers insight into the electrolytic balance of the patient being examined.