The clinical significance of premature atrial contractions: How frequent should they become predictive of new‐onset atrial fibrillation

Abstract

Background Although previous studies reported frequent premature atrial contractions(fPACs) increased the risk of adverse cardiovascular outcomes, especially atrial fibrillation(AF), there is a substantial inconsistency between reports concerning the definition of fPAC. In this study, we aimed to investigate the relationship between fPAC and cardiovascular outcomes, especially AF. We further searched for a cutoff value of fPAC for prediction of AF. Methods We retrospectively analyzed the ambulatory 24‐hr Holter monitoring records and 392 patients included. Frequent PAC was defined as more than 720 PAC/24 hr as used for frequent ventricular premature beats. Patients’ baseline characteristics, echocardiographic variables and medical history were recorded. Results There were 189 patients with fPAC and 203 patients without fPAC. Patients with fPAC had more comorbidities in terms of hypertension, diabetes mellitus, coronary artery disease and congestive heart failure. CHA2DS2‐VaSc was higher in patients with fPAC. Mean follow‐up duration was 31 months, and the number of patients with new‐onset AF during follow‐up was significantly higher in fPAC group (22% vs. 5%, p < .001). fPAC was significantly and independently associated with new‐onset AF and predicted AF with a cutoff value of 3,459 PAC/24 hr, and the risk of AF was 11‐fold higher than those with <3,000 PAC/24 hr. In addition, an increased CHA2DS2‐VaSc score was also associated with new‐onset atrial fibrillation. Conclusion In our study, we have demonstrated that fPAC is significantly associated with new‐onset AF, and this association is the strongest among those patients who have more than 3,000 PAC in 24 hr.

A case of successful catheter ablation of blocked atrial bigeminy and bradycardia with the recovery of normal sinus rhythm and myocardial reverse remodeling

“…It is surprising to observe the electrical reverse remodeling of the reduction of the low‐voltage area after ablation, but the result would be interpreted cautiously requiring further investigations because the number of the points obtained around the low‐voltage area was relatively low in the mapping images. Furthermore, frequent PACs have been reported to predominantly increase the risk of cardiovascular disease, especially atrial fibrillation, 9 , 10 and ablation of PAC could have prevented the future development of atrial fibrillation. However, it is necessary to keep in mind that an alternative strategy and approach must be considered in cases with bradycardia and blocked atrial bigeminy originating from sensitive regions, such as the sinus node and around the atrioventricular node, which are unlikely to be treated by ablation, or those with the failure of the ablation procedure.…”

Could premature ventricular contractions lead to atrial remodeling?

“…To decide if VPC is epicardial we used the maximum deflection index, defined as the ratio between the time to maximum deflection and the QRS duration. We considered a value above .55 as predictive of an epicardial origin 12–14 …”

Development and Validation of an Algorithm for the Digitization of ECG Paper Images

“… Breath artifact : a typical artifact caused by patient breathing [ 20 ]. Premature Atrial Contractions (PACs) : a common cardiac dysrhythmia characterized by premature heartbeats in the atria [ 21 ]. Premature Ventricular Contractions (PVCs) : single ventricular impulses caused by abnormal automatism of the ventricular cells or by the presence of re-entry circuits in the ventricle [ 22 ].…”

“…Premature Atrial Contractions (PACs) : a common cardiac dysrhythmia characterized by premature heartbeats in the atria [ 21 ].…”