Several researchers, cardiologists, radiologists and surgeons studied the anatomy of LA and PV because of a variety of endovascular and surgical techniques used for invasive therapy of patients with AF [2,3,4,5,6,7].
This study once again proves the existence of significant differences in anatomy of LA and PV in AF patients in comparison with healthy individuals [2, 3]. This study presents a significantly larger group of pts. (224 pts) with AF than our previous publication  (82 pts) and other previously published papers – Bittner et al.  (166 pts. with AF.), Kubala et al.  118 pts. with AF. Also the number of PV anomalies is greater than in other studies. [7,8,9,10]. In reference to Chen (710 pts. with AF, 710 pts. CG) et al.  our study is consistent with the dimensions of PVs - larger PVs in AF group, in contrast to our findings in Chen’s study the occurrence of PV variants did not differ between the groups. On the other hand one of the most extensive studies describing PV anatomy by Tekbas et al. shows the prevalence of PV abnormalities only in 26 (3,3%) out of 783 patients without atrial fibrillation .
The VOI ratio defining the shape of the pulmonary vein ostium is useful information for the operator - some research suggest it may define the method of ablatoin (cry ablation vs radio-frequency), predict the outcome and the complications (such as PV occlusion) .
Prior studies have proven that MSCT and cardiac magnetic resonance (CMR) are appropriate, non-invasive, widely available tools for describing LA anatomy and PV attachments in the patients qualified for the ablation procedure [2,3,4,5,6,7,8,9,10,16]. Moreover, CMR images allow for non-invasive therapy stratification using the atrial wall tissue characterization map for fibrosis assessment. It seems to be a good predictor for procedural outcome [2,3,4,5,6,7,8,9,10]. Although it has to be noticed that nowadays the left atrial model reconstruction with imaging by the electroanatomical mapping system is more often performed before the ablation procedure and CT/CMR imaging is not necessary to achieve good results and/or minimize complications [17, 18]. Thus it doesn’t change the significance of our findings.
Similarly to previous observations [2, 3, 8, 19,20,21] the data collected confirm larger diameters of LA, superior and inferior PVs in patients with AF. We want this study to underline the complexity of anatomical changes that may trigger AF.
It has been suggested that those anomalies may affect the results of pulmonary vein ablation [7, 8, 22,23,24]. Kubala et al. describes a superior clinical outcome in patients with typical 4 PV pattern in comparison with the patients with the left CO . Sohns et al. analyzed 138 pts. and proved the impact of PV anatomy on AF recurrence after PVI . Mulder’s et al. study was not conclusive - he presented only statistical trends of the relation between PV anatomy and PVI efficacy .
In contrast, a few studies state the opposite , eg. a recent paper by Heeger et al. analizes the outcome of PVI using cryoballoon in 74 pts. with left common ostia PV; he found the efficacy of PVI equal in the study and the control group, although in some cases the presence of left CO of PV required a different PVI technique .
The lack of decisive opinion on PV anatomy calls for carrying out more studies with larger groups. The full recognition of AF pathophysiology, LA and PV anatomy and remodelling are essential for optimalization of AF treatment strategies.
It should be noted that rare pathological findings were observed in pts. with AF initially qualified for PVI. The precise left atrium visualization helped us to properly qualify the patient for ablation and avoid procedural complications.
Anatomical anomalies of LA and PV may potentially increase the periprocedural complications and affect PVI efficacy . We consider identifying anatomy anomalies as an important factor that may change the operator’s approach and modify the therapeutic strategy.
The main limitation of this paper is the number of patients in the control group.