Your goal is to extract structured information from the user's input that matches the form described below. When extracting information please make sure it matches the type information exactly. Do not add any attributes that do not appear in the schema shown below.

```TypeScript

 { // Information on the clinical trial characteristics from the abstract
 conditions: string // The condition or disease being treated in the clinical trial
 drug_or_intervention: string // The drug or intervention used in the clinical trial
}
```


Please output the extracted information in JSON format. Do not output anything except for the extracted information. Do not add any clarifying information. Do not add any fields that are not in the schema. If the text contains attributes that do not appear in the schema, please ignore them. All output must be in JSON format and follow the schema specified above. Wrap the JSON in <json> tags.



Input:n-3 polyunsaturated fatty acids in the prevention of atrial fibrillation recurrences after electrical cardioversion: a prospective, randomized study.  n-3 polyunsaturated fatty acids (n-3 PUFAs) exert antiarrhythmic effects and reduce sudden cardiac death. However, their role in the prevention of atrial fibrillation remains controversial. We aimed to determine the effect of n-3 PUFAs in addition to amiodarone and a renin-angiotensin-aldosterone system inhibitor on the maintenance of sinus rhythm after direct current cardioversion in patients with persistent atrial fibrillation. We conducted a randomized, double-blind, placebo-controlled, parallel-arm trial in patients with persistent atrial fibrillation, with at least 1 relapse after cardioversion, and treated with amiodarone and a renin-angiotensin-aldosterone system inhibitor. Participants were assigned to placebo or n-3 PUFAs 2 g/d and then underwent direct current cardioversion 4 weeks later. The primary end point was the probability of maintenance of sinus rhythm at 1 year after cardioversion. Of 254 screened patients, 199 were found to be eligible and randomized. At the 1-year follow up, the probability of maintenance of sinus rhythm was significantly higher in the n-3 PUFAs-treated patients compared with the placebo group (hazard ratio, 0.62 [95% confidence interval, 0.52 to 0.72] and 0.36 [95% confidence interval, 0.26 to 0.46], respectively; P=0.0001). In patients with persistent atrial fibrillation on amiodarone and a renin-angiotensin-aldosterone system inhibitor, the addition of n-3 PUFAs 2 g/d improves the probability of the maintenance of sinus rhythm after direct current cardioversion. Our data suggest that n-3 PUFAs may exert beneficial effects in the prevention of atrial fibrillation recurrence. Further studies are needed to confirm and expand our findings. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT01198275. Output:
{'conditions': 'Atrial Fibrillation', 'interventions': 'Drug: n-3 PUFAs|Drug: Placebo|Drug: RASS inhibitors and/or RAS blockers|Drug: Amiodarone'}