Load base64 encoded field

Hello, all I am new to crm, 

I'm reading a database from Microsoft CRM. That works fine. I need to read the notes field from the database (annotation based). Like in this screenshot:

Notes MS CRM

My code for loading the information I need:

LIB CONNECT TO 'CRM';
LOAD someuninterestingfield1,
    someuninterestingfield2,
    someuninterestingfield3,
    someuninterestingfield4,
    someuninterestingfield5,
    someuninterestingfield6,
    BASE64ENCODEDFIELDINEED;
SQL SELECT someuninterestingfield1,
    someuninterestingfield2,
    someuninterestingfield3,
    someuninterestingfield4,
    someuninterestingfield5,
    someuninterestingfield6,
    BASE64ENCODEDFIELDINEED
FROM "CRM_DATABASE".usr.AnnotationBase;

BASE64ENCODEDFIELDINEED has a base64 encoded xml-file I need for my analysis. I have no idea (I couldn't find anything about decoding data while or after loading in Qlik Sense) how to decode the content to finally receive my xml-data. I'm using Qlik Sense 3.0 and MS CRM 2015 (on premise).

Can someone help me?

Thanks in advance.