Can a patient's pulse be falsely low on palpation if they have Premature Ventricular Contractions (PVCs) in the setting of Heart Failure with Reduced Ejection Fraction (HFrEF)?

Pulse Palpation Accuracy in HFrEF Patients with PVCs

Yes, a patient's pulse can be falsely low on palpation if they have premature ventricular contractions (PVCs) in the setting of heart failure with reduced ejection fraction (HFrEF). 1

Mechanism of Pulse Deficit with PVCs

• PVCs can create a "pulse deficit" where the number of palpable peripheral pulses is lower than the actual heart rate detected on ECG 1
• This occurs because PVCs lead to hemodynamically insufficient heartbeats that may not generate enough stroke volume to create a palpable peripheral pulse 2
• The premature contraction occurs before the ventricle has had time to adequately fill, resulting in reduced stroke volume for that beat 2
• In HFrEF patients, this effect is often more pronounced due to already compromised cardiac output and reduced ejection fraction 3

Clinical Significance in HFrEF

• The pulse deficit phenomenon is particularly important in HFrEF patients where accurate heart rate assessment is crucial for management 1
• In patients with HFrEF, the combination of elevated resting heart rate and lower systolic blood pressure identifies patients at highest risk for cardiovascular events 1
• When PVCs are frequent (>10% of heartbeats), they may contribute to symptoms like fatigue and exertional dyspnea that overlap with HF symptoms 2
• Very frequent PVCs (>20% of heartbeats) can potentially worsen cardiomyopathy and heart failure through a PVC-induced cardiomyopathy mechanism 2, 3

Factors Affecting Pulse Deficit in HFrEF

• The severity of pulse deficit correlates with:
  • Frequency of PVCs (more PVCs = potentially greater pulse deficit) 4
  • Severity of heart failure (more advanced HF = greater hemodynamic impact of PVCs) 1
  • Coupling interval of PVCs (shorter intervals = less ventricular filling = less stroke volume) 3
  • Location of pulse being assessed (peripheral pulses more likely to show deficit than central) 2

Clinical Assessment Recommendations

• When assessing heart rate in HFrEF patients with suspected PVCs:
  • Compare pulse rate by palpation with auscultated heart rate or ECG to identify potential pulse deficit 1
  • Consider extended cardiac monitoring in patients with suspected significant pulse deficit to quantify PVC burden 5
  • Be aware that the relationship between PVC frequency and heart rate is often patient-specific and may follow different patterns (increasing with higher heart rates, decreasing, or complex relationships) 4
  • Recognize that PVCs may have different impacts on pulse depending on whether the patient is at rest or during exertion 4

Implications for Management

• In HFrEF patients with frequent PVCs and symptomatic pulse deficit:
  • Consider whether PVCs are the cause or consequence of heart failure 3
  • Evaluate if PVCs are contributing to worsening heart failure symptoms or preventing optimal medication titration 5
  • For patients with right bundle branch block and PVCs, cardiac resynchronization therapy may be considered if QRS duration is prolonged 5
  • Anti-arrhythmic therapy or catheter ablation may be appropriate for very frequent, symptomatic PVCs 2, 3

Pitfalls to Avoid

• Do not rely solely on pulse palpation for heart rate assessment in HFrEF patients with suspected arrhythmias 1
• Avoid assuming that all PVCs are benign, especially in the setting of HFrEF where they may have greater hemodynamic significance 2
• Be cautious about attributing all symptoms to HFrEF alone when frequent PVCs may be contributing to the clinical picture 3
• Remember that subclinical left ventricular dysfunction may be associated with increased ventricular arrhythmias, even before ejection fraction declines significantly 6