The atrial kick contributes to ventricular filling by how many bpm?

• A. 5-10 bpm
• B. 20-30 bpm
• C. 40-50 bpm
• D. 60-70 bpm

Answer: (B)

The key idea is that the atrial kick adds a last push to ventricular filling during late diastole, increasing the ventricle’s preload. In a healthy adult, this atrial contribution amounts to about 20-30% of the filling, meaning roughly one-fifth to one-third of the end-diastolic volume comes from atrial contraction. That’s why the option reflecting the 20-30 range best matches how much the atrial kick typically adds. The bulk of filling is passive during early and middle diastole, and the higher numbers would imply an unusually large reliance on atrial contraction, while the smaller 5-10% would underestimate its role. Note that this is a proportion of filling rather than a direct beats-per-minute value; the concept to remember is that the atrial kick contributes about a fifth to a third of ventricular filling.