Pulmonary veins anatomical determinants of cooling kinetics during second-generation cryoballoon ablation

Pulmonary vein size is associated with reconnection following cryoballoon ablation of atrial fibrillation

BACKGROUND

The second-generation cryoballoon (CB) has proven to be a highly effective ablative strategy in patients with symptomatic atrial fibrillation (AF). This study sought to investigate the anatomical characteristics of pulmonary veins (PVs) and the relationship between their size, ovality, and late reconnections in a large cohort of patients undergoing repeat ablation for recurrence of atrial arrhythmias.

METHODS AND RESULTS

A total of 152 consecutive patients (98 males, 64.5%; mean age 64.9 ± 9.6 years) underwent a repeat ablation for recurrent atrial tachyarrhythmias after a median time of 6.5 months [IQR 11] from the index CB ablation. All repeat ablations were performed using a 3-dimensional electro-anatomical mapping system. Among all 593 PVs, 134 (22.6%) showed a late PV reconnection in 95 patients (0.88 per patient), at the time of repeat ablation procedure. There was a significant difference in ovality between left- and right-sided PVs (p < 0.001). Greater diameters of left superior PV, left inferior PV, and right inferior PV ostia (both maximum and minimum) and higher index ovality were significantly associated with late PV reconnection.

CONCLUSIONS

The rate of late PV reconnection after CB ablation was low (0.88 PVs/patient). Left-sided PVs were more oval than septal PVs. Larger PV dimensions and higher ovality index were significantly associated with reconnections in all PVs except for RSPV.

Variations in human pulmonary vein ostia morphology: A systematic review with meta-analysis

This study aimed to establish the most accurate and up-to-date anatomical knowledge of pulmonary veins (PV), ostia variations, diameters and ostial area, to provide physicians, especially heart and thoracic surgeons with exact knowledge concerning this area. The main online medical databases, such as PubMed, Embase, Scopus, Web of Science, and Google Scholar, were searched to gather all studies in which the variations, maximal diameter, and ostial area of the PVs were investigated. During the study, the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed. Additionally, the critical appraisal tool for anatomical meta-analysis (CATAM) was used to provide the highest quality findings. The most common ostia variation is the classical one, which contains the left superior pulmonary vein (LSPV), left inferior pulmonary vein (LIPV), right superior pulmonary vein (RSPV) and right inferior pulmonary vein (RIPV). The mean diameter and ostial area of each pulmonary vein were established in the general population and in multiple variations considering the method of collecting the data and geographical location. Significant variability in PV ostia is observed. Left-sided PVs have smaller ostia than the corresponding right-sided PVs, and the inferior PVs ostia are smaller than the superior. The LCPV ostium size is the largest among all veins analyzed, while the RMPV ostium is the smallest. The results of this meta-analysis are hoped to help clinicians in planning and performing procedures that involve the pulmonary and cardiac areas, especially catheter ablation for atrial fibrillation.