How to loop over a field’s value one after another and do aggregation operations on it?

I recently started working with MongoDB and its aggregation pipeline. I need some help with looping over the field called Id and doing aggregation operation on it one after another directly inside pipeline.

Currently I am doing something like this (in Node.js):

let patients = await client.db('MyDB').collection('Patients_MA').find().toArray();

for (int i=0; i<patients.length; i++)
{
    doc = patientColl.aggregate([
      {
        $match: {Id: patients[i].Id}
      }, 
      {
        $project: {
          _id: 0, 
          num: {
            $add: [
              {$multiply: [0.7, 2]},
              {$multiply: [0.2, 2]},
              {$multiply: [0.15, 0]}
            ]
          }
        }
      }
    ]);

    await patientsColl.updateOne(
        { "Id": id },
        { "$set": {'heuristic': num} }
    );
}

For the sake of easy understanding I have condensed the pipeline to just the main thing I want it to do which is to update the heuristic value but in my original pipeline, each Id will have a different heuristic value. Also, I have approximately 8000 patients Ids and in my original pipeline, I am working with 3 different collection.

So my question is, is there a way to loop over each Id‘s, run the the pipeline above, and update the heuristic value directly inside the aggregation pipeline? Or a way to do this more efficiently without having to make O(8000) calls?