Send SMS/IM based on HR threshold

Scoping out the feasibility of the idea, the work required as well as the hoops to jump through.

Typical scenario:
- Family member has a cardiology issue
- Apple watch's batt life is too little to have make it an acceptable adoption
- Alternatives (except Garmin) has somewhat unreliable platform/sensor
- Coder me tries to contribute with technology rather than be more caring and attentive.

The main goal is for other family members to get SMS/Telegram/Whatsapp notifications when the HR exceeds a threshold. 

As far as I can tell, the simplest would be

1. a watch app that reads the HR
2. watch app communicates HR via JSON REST Requests (via Mobile Proxy https://developer.garmin.com/connect-iq/core-topics/https/#jsonrestrequests) to a web service
3. Web service relies on an SMS Service to send SMS.

Alternatively,
1. a watch app that reads the HR
2. a watch app that communicates HR to a companion IQ app on the mobile phone
3. Companion IQ app somehow SMS others using the phone's SIM card/esim

Is solution 1 feasible? Cause there are a couple of uncertainties I have with the second solution.