Concerned about my senior dog — BNP 1806, coughing, collapsing, reduced appetite. What should my next steps be?

I am hoping to get some guidance and perspective from the vets here. I am feeling very worried and just want to make the best decisions for my dog.

My Catahoula is 10 years old and has always been an active and lively dog, full of personality. Over the past few weeks, he has been coughing more, eating less, and in the last few days, he has had a couple of episodes where he suddenly falls down the stairs or off the couch. Our vet ran blood work, and his BNP came back at 1806, which I understand is quite high.

I am trying hard not to jump to conclusions, but I also do not want to ignore what might be a serious situation. I love this dog and want to do everything I can to help him feel better, stay comfortable, and remain safe.

We plan to get an echocardiogram as soon as possible, but while we are arranging that, I want to ensure we are taking the right steps in the meantime.

For anyone willing to share advice, I have a few questions:

• Does a BNP this high usually mean heart failure, or can other conditions cause numbers like this
• Is this level so high that treatment options are limited, or is it still possible to help him improve his quality of life
• While we wait for the echo, what would you recommend as the most important next step, such as chest X-rays, medications, or something else
• Are there any signs that should make me seek emergency care immediately

He is still with me, but he is definitely not himself, and I do not want to wait too long if early action could help him. Any insight you can offer would be greatly appreciated. Thank you for taking the time to read this and for the work you do. I truly appreciate it.