Evolution of strategies in the non-pharmacologic management of atrial fibrillation: a review

Atrial fibrillation is the commonest amongst all sustained cardiac dysrhythmias. Besides in its idiopathic form seen in the elderly, it may co-exist with other cardiac disorders, especially rheumatic valvular heart disease. No pharmacotherapeutic combination has yet succeeded in comprehensively addressing the three detrimental sequelae of atrial fibrillation viz, the subjective discomfort of an irregular heartbeat, compromised cardiac haemodynamics caused by the loss of synchronous atrioventricular contraction, and the stasis of blood flow in the left atrium threatening thrombo-embolism. Percutaneous catheter interventions, too, have been equally unsuccessful. However, several innovative surgical solutions have been designed in the laboratory as well as in clinical setting. The most successful amongst these is the Maze III procedure. It is a complex operation which deploys a number of predesignated incisions in both atria along with cryolesions applied at certain vantage points. The objective is to interrupt micro re-entrant circuits in the atria while ensuring that the SA node is able to generate and propagate the sinus impulse through both atria. In spite of its immense success, the prolonged duration of myocardial ischaemia and cardiopulmonary by-pass, especially when accompanied by associated valve related procedures have come in the way of its popularity. Efforts are underway to replicate the Maze radiofrequency incisions using radiofrequency energy to produce equally efficient intramural ablation within a much shorter time. Catheters capable of creating contiguous multiple transmural linear lesions are being developed to facilitate rapid ablation of atria. Their induction is likely to significantly reduce the surgical duration, thus making the Maze procedure more popular. Thus it is evident that for the moment the onus and privilege of 'curing' atrial fibrillation will rest with the cardiac surgeons.