The developing pulmonary veins and left atrium: implications for ablation strategy for atrial fibrillation†

Atrial fibrillation (AF) is the most common clinically relevant cardiac arrhythmia. AF poses patients at increased risk of thromboembolism, in particular ischemic stroke. The CHADS2 and CHA2DS2-VASc scores are useful in the assessment of thromboembolic risk in nonvalvular AF and are utilized in decision-making about treatment with oral anticoagulation (OAC). However, OAC is underutilized due to poor patient compliance and contraindications, especially major bleedings. The Virchow triad synthesizes the pathogenesis of thrombogenesis in AF: endocardial dysfunction, abnormal blood stasis, and altered hemostasis. This is especially prominent in the left atrial appendage (LAA), where the low flow reaches its minimum. The LAA is the remnant of the embryonic left atrium, with a complex and variable morphology predisposing to stasis, especially during AF. In patients with nonvalvular AF, 90% of thrombi are located in the LAA. So, left atrial appendage occlusion could be an interesting and effective procedure in thromboembolism prevention in AF. After exclusion of LAA as an embolic source, the remaining risk of thromboembolism does not longer justify the use of oral anticoagulants. Various surgical and catheter-based methods have been developed to exclude the LAA. This paper reviews the physiological and pathophysiological role of the LAA and catheter-based methods of LAA exclusion.

show abstract

“…LAA is a remnant of the embryonic left atrium [ 1 ], while the rest of the left atrial cavity derives from an outgrowth of the pulmonary veins.…”

Section: Introductionmentioning

confidence: 99%

Left Atrial Appendage: Physiology, Pathology, and Role as a Therapeutic Target

Regazzoli

Ancona

Trevisi

et al. 2015

BioMed Research International

View full text Add to dashboard Cite

show abstract

“…During the development of the human embryo, an initially solitary pulmonary vein is incorporated with its tributaries by an expanding left atrial wall: this progressive growth leads to four separate pulmonary veins with distinct ostia arising from the left atrium. 7 The superior segment right lower lobe vein (V6) draining separately from the basilar segments right lower lobe vein into the left atrium, in a patient with a normal right upper lobe venous drainage, is a rare anatomical variant and requires a careful isolation of hilar structures to prevent the risk of intraoperative vessel injury. Variations in the number and course of pulmonary veins are more common on the right side and a great number of anomalies involve the venous drainage pattern of the right middle lobe.…”

Section: Discussionmentioning

confidence: 99%

Multiple variations in pulmonary veins during a thoracoscopic right lower lobectomy: A case report

et al. 2020

View full text Add to dashboard Cite

A knowledge of pulmonary vein anatomy variants allows an appropriate preoperative radiological assessment and safe surgical management of vascular anomalies in patients undergoing major lung resections. In our case, multiple pulmonary vein variations were identified pre‐ and intraoperatively in a patient undergoing thoracoscopic right lower lobectomy and included superior and common basal veins from the right lower lobe draining separately into the left atrium, middle lobe veins joining the superior segment right lower lobe vein and additional superior segment right lower lobe vein draining directly into the left atrium. The recognition of these anatomical abnormalities in pulmonary veins may help thoracic surgeons avoid surgical complications in patients undergoing anatomical lung resections.

show abstract

“…It has not been determined whether the increase in LAA volume is a cause or a consequence of AF. The LAA is a remnant of the embryonic left atrium, while the remaining left atrium is derived from an outgrowth of the pulmonary veins [21]. It appears to play an important role in the regulation of heart rate and fluid balance [22] through a distensible reservoir function and its capacity for atrial natriuretic peptide (ANP) secretion, as well as stretch sensitive receptors [23], accompanied by an intrinsic contractile capability.…”

Section: Discussionmentioning

confidence: 99%

Left Atrial Appendage Volume and Plasma Docosahexaenoic Acid Levels Are Associated With Atrial Fibrillation Recurrence After Catheter Ablation

Shiozawa¹,

Shimada²,

Sekita³

et al. 2017

Cardiol Res

View full text Add to dashboard Cite

BackgroundRisk factors for atrial fibrillation (AF) recurrence in patients who have undergone AF catheter ablation have not been fully clarified. The objective of this study was to assess whether the left atrium (LA) and LA appendage (LAA) volumes, and cardio-metabolic markers such as polyunsaturated fatty acids (PUFAs) levels were associated with AF recurrence.MethodsSeventy-seven consecutive patients with AF (mean age, 59 ± 8 years; male, 81%; paroxysmal AF, 64%) undergoing catheter ablation were enrolled. Using contrast-enhanced cardiac multi-detector computed tomography (MDCT) scan, the LA and LAA volume and orifice area were assessed. Radiofrequency ablation was performed by an irrigation catheter, initially targeting the pulmonary veins with a wide area circumferential ablation.ResultsPatients with AF recurrence (36%) exhibited both larger LAA volumes and an LAA orifice area than those without AF recurrence, whereas the LA diameter and LA volumes were not significantly different. Notably, AF recurrence occurred in all patients with a large LAA (≥ 25 mL), and the LAA volume was significantly and negatively associated with docosahexaenoic acid (DHA) levels (β = -0.33, P = 0.003). A multiple regression analysis revealed that the log N-terminal proB-type natriuretic peptide and plasma DHA levels were independent factors for the LAA volume when adjusted for age, AF detected age, left ventricular (LV) ejection fraction, end-systolic LV diameter.ConclusionsThese results suggest that the association between LAA volume and low plasma DHA levels may be an important factor for post-ablation AF recurrence.

show abstract

The developing pulmonary veins and left atrium: implications for ablation strategy for atrial fibrillation†

Cited by 32 publications

References 54 publications

Left Atrial Appendage: Physiology, Pathology, and Role as a Therapeutic Target

Left Atrial Appendage: Physiology, Pathology, and Role as a Therapeutic Target

Multiple variations in pulmonary veins during a thoracoscopic right lower lobectomy: A case report

Left Atrial Appendage Volume and Plasma Docosahexaenoic Acid Levels Are Associated With Atrial Fibrillation Recurrence After Catheter Ablation

Contact Info

Product

Resources

About