R DiagrammeR package Mermaid text using actual calculation results

I would like to utilize the DiagrammeR package for a simple flow chart in my Rmarkdown. However, I couldn't figure out a way to use actual output from a data table into the text. Suppose I have a simple query of a database with total records, patients count and date in year info for three different cohorts. I wanted to create a diagram using Mermaid. The codes look at this.

Total = paste0('Records:',b1$records,' Patients:',b1$patients,' Year:',b1$year)
# (Records:1000 Patients:822 Year:5)
Sub1 = paste0('Records:',b2$records,' Patients:',b2$patients,' Year:',b2$year)
Sub2 = paste0('Records:',b3$records,' Patients:',b3$patients,' Year:',b3$year)

mermaid("
graph TB
  A[Total] --> B{Sub1} --> C{Sub2}
  ")

Instead of Printing out diagram with: Records:1000 Patients:822 Year:5 in the A, it shows verbatim word "Total".

Any suggestion on how to do it correctly?

Thanks!

You are one step away from what you'd like to achieve. Please try this simple example below to see the logic:

library(DiagrammeR)

Stracture:

DiagrammeR(
  "
  graph TB
  
  A[Question] -->B[Answer]
  "
)

1. Define answer node:

B <- paste0("There are ", nrow(iris), " records")

2. Combine it with other components, using ; to separate statements:

results <- paste0("graph TB; A[How many rows does iris have?]-->", "B[", B, "]")

3. Call 'results' in DiagrammeR:

DiagrammeR(diagram = results)

The final plot should refresh when your calculation updates.

The plot that calls your calculation