If my husband died with credit card debt that was only in his name, am I responsible for paying it? 

If the credit card debt was incurred during marriage, then the debt is presumed to be a community debt, and you would be liable for them.

First of all, if your husband left an estate, then the creditors will paid out if it.  If there is no estate or not enough assets to pay down his debt, then in most states, that's the end of it and the debt extinguishes as a matter of law.  However, in community property states, such debts are deemed to be incurred for the benefit of the community and are therefore considered to be community property debt.  Since LA is a community property state, you will most probably be responsible for repayment.

For specifics, you need to consult directly with an attorney in your area.