Internal audit

According to the ISO 13485:2016, requirement 8.2.4 Internal audit states that the organization must conduct internal audits at planned intervals. The purpose of an internal audit is to determine whether your quality management system conforms to both all documented arrangments, requirements of the ISO 13485:2016, and all other applicable regulatory requirements. So, yes, you need to perform another internal audit to assess the compliance with MDR. 

For more information on how the internal audit should be performed, please see following articles: 

• Five main steps in the ISO 13485:2016 internal audit - https://advisera.com/13485academy/knowledgebase/five-main-steps-in-the-iso-134852016-internal-audit/
• How to create a checklist for an ISO 13485 internal audit for your QMS - https://advisera.com/13485academy/knowledgebase/how-to-create-a-checklist-for-an-iso-13485-internal-audit-for-your-qms/
• Checklist of ISO 13485 implementation and certification steps - https://advisera.com/13485academy/knowledgebase/checklist-of-iso-13485-implementation-and-certification-steps/

You can even see which documents our ISO 13485:2016 Internal audit documentation toolkit have:

• ISO 13485:2016 Internal Audit Toolkit https://advisera.com/13485academy/iso-13485-internal-audit-toolkit/