Left atrial fibrosis by late gadolinium enhancement cardiovascular magnetic resonance predicts recurrence of atrial fibrillation after pulmonary vein isolation: do you see what I see?

A trial fibrillation (AF) is the most common sustained arrhythmia with 3 to 6 million currently afflicted and the prevalence expected to double by 2050. 1 AF carries an increased risk of cardiovascular morbidity and mortality driven largely by increased risk of stroke and congestive heart failure. 1 Management of AF represents a significant and growing healthcare burden, with an estimated cost of $6.65 billion in 2005 and likely doubling by 2020. Treatment of AF historically consists of anticoagulation to reduce the incidence of clinical stroke followed by either rate control or rhythm control. Both choices have been shown to produce similar outcomes (Atrial Fibrillation Follow-up Investigation of Rhythm Management [AFFIRM]), 3 and thus rhythm control has been recommended for those who are symptomatic. Until recently, rhythm control had been most commonly achieved with the use of repeated cardioversions and antiarrhythmic therapy—many of which have undesirable side effects and potential toxicities. 4 Surgical treatment using the Maze procedure (and its many modifications) makes physiological sense (interfering with the macroreentrant circuit in the atria) but is quite invasive. The advent of catheter-based therapies for rhythm management of AF has revolutionized the electrophysiological field and provides a less invasive approach similar to the surgical Maze procedure goals. Pulmonary vein isolation (PVI), the most commonly used catheter-based technique, aims to electrically isolate the pulmonary veins, a major source of ectopy that may trigger AF, 5 using catheter-based mapping and abla-tion tools. 6 Despite the excitement and ensuing enormous industry growth in this field, PVI has been met with mixed long-term success with concerns of both short-term safety and long-term efficacy. As a result, treatment guidelines remain controversial. 6,7 Several studies have demonstrated clinical features that predict long-term PVI success, including par-oxysmal over persistent or permanent AF. 8 Despite our best efforts, clinical variables fail to adequately define those who will have a successful procedure defined as long-term, sustained sinus rhythm. Therefore, alternative/supplemental risk schema is desired. Noninvasive imaging has played a role in preprocedural planning and post-PVI monitoring. Pre-PVI cardiovascular magnetic resonance (CMR) and cardiac computed tomogra-phy are often used to determine the location and anatomy of the pulmonary veins, whereas postprocedure CMR and computed tomography are used to monitor for complications such as pulmonary vein stenosis. Cardiac ultrasound (transesopha-geal and intracardiac) is often used for preprocedure exclusion of left atrial (LA) appendage thrombi, intraprocedural catheter guidance of transseptal puncture and ablation, and …