One of the biggest problems people have with understanding certain diets is that they remember incorrectly what was said, and things are sometimes lost in the interpretation. You really need something in writing you can refer to frequently. I really can't imagine that one physician would have a low-sodium diet plan for CHF patients much different from another since they all get their information from the same sources. The one caveat to that statement would be if there were additional restrictions or requirements for another underlying condition.
Here is something worth reading: Diet for the Treatment of Heart Failure
This info is from the Clinical Dietitians, Nutrition Services, Southern New Hampshire Medical Center ... the Information is adapted from Manual of Clinical Dietetics
, American Dietetic Association, 6th Edition, © 2000