What is the physiological impact of tachycardia on an already compromised heart?

Tachycardia, which is defined as an abnormally fast heart rate, can have significant physiological consequences, especially on a heart that is already compromised. When the heart beats faster, it tends to increase the overall demand for oxygen. This occurs because the heart muscle requires more oxygen to sustain its heightened activity; a faster heart rate means that the myocardium (the heart muscle) is working more vigorously.

In instances where the heart is already struggling—due to conditions such as heart failure, ischemic heart disease, or any other form of cardiac dysfunction—this increased demand can exacerbate the problem. The compromised heart may not be able to meet the greater oxygen demands, leading to symptoms such as chest pain, fatigue, and worsening heart function.

Other options, such as the idea that tachycardia might result in increased blood flow to vital organs or improve cardiac output, do not hold true in the context of a heart that is already compromised. While faster heart rates might initially seem to suggest enhanced blood flow, it often leads to inadequate perfusion, as the heart may not be able to fill properly during the shortened diastolic phase when the heart rate is increased. Thus, the physiological reality of tachycardia in a