I am a quadriplegic and cannot use my hands. I was hoping Amazon echo could control my new TV. Does anyone know of a way I can do that?
Welcome! I am myself quadriparetic, use a wheelchair with very limited hand function, and consequently I do use voice for almost everything. The echo has been really great for me. 
Later this year there is supposed to be a new SmartThings option available for high-end Samsung TVs, but it has not yet been released. @tyler might be able to say more on that.
Meanwhile, if you are willing to buy the $99 Logitech Harmony hub, you can get very good integration with echo for basic harmony activities. That includes turning the TV on and off, changing to different inputs like a Roku or a fire TV, and going to a specific channel like ESPN or the Disney Channel. There are various button remotes you can buy to go with it if there are other people in your household who would like a universal remote, but if you’re only going to use it for voice, then the Harmony hub piece is all that you need. Plus the Amazon echo.
https://www.amazon.com/Logitech-Harmony-Smartphone-Entertainment-Automation/dp/B00N3RFC4Q/
You Can also use voice to change volume, but it’s pretty clunky. I think most able-bodied people would prefer to use the button remote for that. But it is doable, and I do use it.
There are multiple ways to use harmony and echo together. There is an official SmartThings/Harmony integration, but I have not found it to be reliable enough for my purposes. So I just use the official echo/IFTTT integration, which I find works very well. That is the first option discussed in the following thread:
If you prefer to use the official smartthings/harmony integration, it is discussed here:
Again, by the end of this year there may be a much more direct integration which does not require the harmony, it’s just not available yet.
Also I should say that harmony and Amazon are working on an official harmony/echo integration that would not require IFTTT. It’s in beta right now, and no telling when it will be available to everyone. I’m hoping this will mean we’ll get much easier volume control, but no way to tell for sure yet.
As it is now, just to give more details, I have to have two activities for volume up and two activities for volume down, because harmony will not let you repeat the same activity twice in a row. So say I want to watch ESPN and turn the volume up 3 notches. These are the echo commands I would have to give.
“Alexa, trigger ESPN.” ( works great, adjusts the inputs, turns on the TV, switches to the right channel, all from one voice command.)
“Alexa, trigger volume A.” (That’s my command to turn the volume up one notch.)
“Alexa, trigger volume B.” ( does exactly the same thing as Volume A, turn the volume up one notch, but because harmony won’t let me do the same activity twice in a row I have to switch between them.)
“Alexa, trigger volume A.” ( The third notch)
“Alexa, trigger ESPN.” ( I have to do this one more time in order to get everything synced up again.)
So you can see this is really annoying. And clunky. But it does work. And I keep hoping that there will eventually be a new integration that will do this more gracefully.
On the other hand, everything else works great. If I was watching ESPN and I want to watch HBO, I just say “Alexa, trigger HBO.” 
So I’ve been really happy with the options I have now compared to what I had before echo and harmony. It’s just the volume changes which are so awkward.
Depending on your level of technical ability, this is an option as well:
It’s a direct link between Alexa and Harmony hub, bypassing SmartThings completely.
The setup process is fairly complicated and the code will need some customization for your specific needs, but it allows the ability to issue direct button-press commands to the Harmony hub, like “volume up 3” or “go to channel 12” or pause, play, select, back, etc, which is much cleaner than setting up routines for every button press.