Make sure to keep up earth shield and 3x healing stream totems; makes a huge difference. My '=' key is bound to a slightly downranked Healing Wave on my resto shammy, and lightning bolt on my ele shammies. It's mostly what I use in heroics. If I'm dodging/parrying a lot, I'll hit my '-' key, which is lightning bolt on all of them. If I'm getting hit a lot, I'll use the '9' key, which is lesser healing wave on all of them.

It's all about keeping an eye on the situation and anticipating when the damage will come. The very beginning of a pull is usually hardest. I just continually hit the '=' key, even if it means wasting a heal or two, until things have stabilized. If things get rough, just spam 4xLHW until you catch up again. Don't be afraid to drink a health potion; they're cheap. Also, make good use of your HoJ. It's amazing how much of a difference it makes taking one enemy out of the equation for a few seconds. This is especially useful on the the bogstrok pulls in SP; stun one, and kill it before the stun wears off. It turns a 4-pull into a 3-pull or a 3-pull into a very manageable 2-pull.

This is my pally's armory: http://www.wowarmory.com/character-s...uramar&n=Aeara
12527 hp, 14981 armor, 474 def, 71 resilience, 13% dodge 13% parry 15% block

I first started doing heroics with MUCH worse gear than that (10.5K HP, 10K armor). Even with better gear, I regularly get taken down to 2-3K hp in the first two seconds on many heroic pulls. But that's rarely cause for worry, because I know I always have a nice fat healing wave 0.1 seconds away from landing.