Left atrial ablation for management of atrial fibrillation: CABANA vs. real-world data. Apples and oranges?

A comprehensive evaluation of the left atrium using cardiovascular magnetic resonance

Atrial disease or myopathy is a growing concept in cardiovascular medicine, particularly in the context of atrial fibrillation, as well as amyloidosis and heart failure. Among cardiac imaging modalities, cardiovascular magnetic resonance (CMR) is particularly well suited for a comprehensive assessment of atrial myopathy, including tissue characterization and hemodynamics. The goal of this review article is to describe clinical applications and make recommendations on pulse sequences as well as imaging parameters to assess the left atrium and left atrial appendage. Furthermore, we aimed to create an overview of current and promising future emerging applications of left atrium-specific CMR pulse sequences focusing on both electrophysiologic (EP) and non-EP applications.

Catheter ablation superiority over the pharmacological treatments in atrial fibrillation: a dedicated review

Atrial fibrillation globally affects roughly 33.5 million people, making it the most common heart rhythm disorder. It is a crucial arrhythmia, as it is linked with a variety of negative outcomes such as strokes, heart failure and cardiovascular mortality. Atrial fibrillation can reduce quality of life because of the potential symptoms, for instance exercise intolerance, fatigue, and palpitation. There are different types of treatments aiming to prevent atrial fibrillation and improve quality of life. Currently, the primary treatment for atrial fibrillation is pharmacology therapy, however, these still show limited effectiveness, which has led to research on other alternative strategies. Catheter ablation is considered the second line treatment for atrial fibrillation when the standard treatment has failed. Moreover, catheter ablation continues to show significant results when compared to standard therapy. Hence, this review will argue that catheter ablation can show superiority over current pharmacological treatments in different aspects. It will discuss the most influential aspects of the treatment of atrial fibrillation, which are recurrence and burden of atrial fibrillation, quality of life, atrial fibrillation in the setting of heart failure and mortality and whether catheter ablation can be the first line treatment for patients with atrial fibrillation.

Acute enhancement of necrotic radio-frequency ablation lesions in left atrium and pulmonary vein ostia in swine model with non-contrast-enhanced T1 -weighted MRI

PURPOSE

To evaluate non-contrast-enhanced MRI of acute radio-frequency ablation (RFA) lesions in the left atrium (LA) and pulmonary vein (PV) ostia. The goal is to provide a method for discrimination between necrotic (permanent) lesions and reversible injury, which is associated with recurrence after treatment of atrial fibrillation.

METHODS

Fifteen normal swine underwent RFA around the right-superior PV ostia. Electrical pulmonary vein isolation (PVI) was verified by electro-anatomic mapping (EAM) and pacing. MRI was carried out using a 3D respiratory-gated T1 -weighted long inversion time (TWILITE) sequence without contrast agent. Key settings were: inversion time 700 ms, triggering over 2 cardiac cycles, pixel size 1.1 mm3 . Contrast-enhanced imaging and T2 -weighted imaging were carried out for comparison. Six animals were sacrificed on ablation day for TTC-stained gross pathology, 9 animals were sacrificed after 2-3 mo after repeat EAM and MRI. Image intensity ratio (IIR) was used to measure lesion enhancement, and gross pathology was used to validate image enhancement patterns and compare lesion widths.

RESULTS

RFA lesions exhibited unambiguous enhancement in acute TWILITE imaging (IIR = 2.34 ± 0.49 at 1.5T), and the enhancement patterns corresponded well with gross pathology. Lesion widths in MRI correlated well with gross pathology (R2 = 0.84), with slight underestimation by 0.9 ± 0.5 mm. Lesion enhancement subsided chronically.

CONCLUSION

TWILITE imaging allowed acute detection of permanent RFA lesions in swine LA and PV ostia, without the need for contrast agent. Lesion enhancement pattern showed good correspondence to gross pathology and was well visualized by volume rendering. This method may provide valuable intra- or post-procedural assessment of RFA treatment.