From the Guidelines
Yes, there is a link between frequent Premature Atrial Contractions (PACs) and atrial fibrillation, as patients with frequent supraventricular premature beats (SVPBs), which include PACs, have a higher probability of developing atrial fibrillation 1. The relationship between PACs and atrial fibrillation is complex, but it is thought to be due to shared underlying mechanisms, such as atrial remodeling, increased atrial pressure, or autonomic nervous system imbalances.
- Key factors that contribute to this link include:
- Atrial remodeling, which can lead to electrical instability in the atria
- Increased atrial pressure, which can trigger episodes of atrial fibrillation
- Autonomic nervous system imbalances, which can disrupt the normal electrical activity of the heart For patients with frequent PACs, especially those with risk factors for atrial fibrillation, such as hypertension, close monitoring and preventive measures may be warranted, including lifestyle modifications like optimizing BP control, especially in patients with left ventricular hypertrophy (LVH) 1.
- Management strategies may include:
- Lifestyle changes, such as addressing precipitants relevant to some patients (e.g., alcohol, caffeine)
- Optimizing BP control, especially in patients with LVH
- Prolonged ECG monitoring to detect atrial fibrillation in patients with frequent SVPBs and LVH 1 It's essential to note that while there is a link, not all individuals with frequent PACs will develop atrial fibrillation, and the relationship is influenced by various factors, including genetics, age, and overall cardiovascular health. Regular cardiac check-ups and discussions with a healthcare provider are crucial for individuals experiencing frequent PACs to assess their individual risk and determine appropriate management strategies.
From the Research
Association between Premature Atrial Contractions (PACs) and Atrial Fibrillation
- Frequent PACs are associated with an increased risk of atrial fibrillation (AF), stroke, and death 2.
- The relationship between PACs and AF is supported by studies showing that frequent PACs can trigger AF 2, 3.
- PACs previously considered benign are now recognized as a potential precursor to AF, especially when frequent 3.
Electrophysiological Features and Catheter Ablation
- A study on symptomatic frequent PACs found that catheter ablation was effective in eliminating PACs in most patients 2.
- The electrophysiological features of PACs, including coupling intervals, were compared between patients with and without AF induced by PACs 2.
- Ectopic foci of PACs were commonly found in the pulmonary veins, crista terminalis, and para-Hisian area 2.
Lifestyle and Risk Factor Modification
- Modifying lifestyle risk factors, such as physical activity and body mass index (BMI), may help reduce the frequency of PACs and subsequently the risk of AF 4, 5.
- A study found that each 1-point increase in the Life's Simple 7 (LS7) score was associated with lower odds of frequent PACs 4.
- Physical activity and BMI were identified as individual LS7 factors associated with higher odds of PACs frequency 4.
Left Atrial Contractile Function and Remodeling
- Frequent PACs have been shown to impair left atrial contractile function and promote adverse left atrial remodeling 6.
- Patients with frequent PACs had reduced left atrial peak contractile strain and larger left atrial volume index compared to controls 6.
- Frequent PACs were an independent predictor of reduced left atrial peak contractile strain and strain rate 6.
Predictors of Atrial Ectopy and AF Risk
- Predictors of baseline PAC frequency include increasing age, height, and history of myocardial infarction 5.
- Modifiable predictors, such as beta-blocker use and moderate-intensity exercise, were associated with fewer PACs 5.
- Higher PAC frequency explained a significant proportion of the relationship between increasing age and AF risk, as well as taller height and AF risk 5.