The arduinoPulse.ino file will need to be uploaded to your Arduino through the Arduino IDE, then the node project runs separately.
In app.js, you will have to change the hard-coded value of the port your Arduino is connected to. You can get the name of this port from the Arduino IDE setup.
In your terminal, from the project root folder, run npm install
When that successfully completes, run node app.js
Navigating to http://localhost:8081/ in your browser will show your visualization.