How do premature ventricular contractions (PVCs) affect pulse?

From the Guidelines

Premature ventricular contractions (PVCs) cause irregularities in the pulse, typically felt as a skipped beat followed by a stronger than normal beat. During a PVC, the heart's ventricles contract earlier than they should, before being properly filled with blood. This early contraction is usually ineffective at pumping much blood, creating the sensation of a missed beat in the pulse. The pause following the PVC allows the heart to fill more completely with blood, resulting in a stronger subsequent contraction that feels more forceful when taking a pulse. PVCs may occur in patterns (such as bigeminy, where every other beat is a PVC) or as isolated events. While occasional PVCs are common and often benign in healthy individuals, frequent PVCs (generally more than 10-15% of total heartbeats) may indicate underlying heart disease, as suggested by the 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death 1.

The physiological impact of PVCs occurs because they disrupt the heart's normal electrical conduction system, originating from an ectopic focus in the ventricles rather than from the sinoatrial node, which normally controls heart rhythm. According to the guideline, frequent PVCs (usually >15% of the total number of beats) may produce a reversible form of LV dysfunction 1. Treatment with a beta blocker or non-dihydropyridine calcium channel blocker is useful to reduce recurrent arrhythmias and improve symptoms in patients with symptomatic PVCs in an otherwise normal heart 1. Additionally, catheter ablation is useful for patients who require arrhythmia suppression for symptoms or declining ventricular function suspected to be due to frequent PVCs 1.

Some key points to consider when evaluating the impact of PVCs on pulse include:

• The frequency and pattern of PVCs, as these can indicate underlying heart disease or other conditions
• The presence of symptoms such as palpitations, shortness of breath, or chest pain, which can be associated with PVCs
• The results of diagnostic tests such as electrocardiograms (ECGs) or Holter monitoring, which can help identify PVCs and other arrhythmias
• The patient's overall health status and medical history, as certain conditions can increase the risk of complications from PVCs.

Overall, PVCs can have a significant impact on pulse and overall heart health, and it is essential to evaluate and manage them appropriately to prevent complications and improve quality of life.

From the Research

Effect of PVCs on Pulse

• Premature ventricular contractions (PVCs) are heartbeats initiated in the ventricles instead of in the sinoatrial node, which can lead to changes in pulse 2.
• A high burden of PVCs can result in reduced left ventricular (LV) systolic dysfunction, characterized by a decrease in the left ventricular ejection fraction 2.
• PVCs can also lead to right ventricular (RV) systolic dysfunction, as seen in a case study where a patient had mild RV systolic dysfunction along with LV systolic dysfunction 2.

Mechanism of PVC-Induced Changes in Pulse

• The exact mechanism of how PVCs affect pulse is not fully understood, but it is thought that a high burden of PVCs can lead to cardiomyopathy, characterized by reduced LV systolic function 3.
• PVC-induced cardiomyopathy is a condition where the frequent occurrence of PVCs leads to a decline in cardiac function, resulting in symptoms such as palpitations, fatigue, and heart failure 4.

Diagnosis and Treatment of PVC-Induced Changes in Pulse

• Diagnosis of PVC-induced changes in pulse typically involves a 24-hour Holter monitor to assess the burden of PVCs, as well as echocardiography to evaluate LV and RV function [(2,4)].
• Treatment of PVC-induced changes in pulse may involve beta-blockers, antiarrhythmic drugs, or catheter ablation of PVCs, depending on the underlying heart disease and frequency of PVCs [(3,4,5)].

Special Considerations

• In some cases, PVCs may be triggered by underlying conditions such as obstructive sleep apnea (OSA), and treatment of the underlying condition may be necessary to alleviate PVCs 6.
• Traditional Chinese medicine (TCM) has been shown to be effective in treating PVCs caused by OSA in a case report, but more research is needed to establish its efficacy and underlying mechanisms 6.