Sodium and Fluid Balance in ATTR-CM: What You Need To Know

Living with transthyretin amyloid cardiomyopathy (ATTR-CM) can make you think about your body in new ways. For example, your sodium and fluid balance could now be a daily concern.

And understandably so. ATTR-CM can cause your body to retain water and sodium, making heart failure symptoms worse.

Cardiologist Wai Hong Wilson Tang, MD, explains the intricacies of managing sodium fluid balance with ATTR-CM — and what you can do in your daily life to help keep your levels in check.

Why sodium and fluid matter in ATTR-CM

The balance of sodium and fluid in your body gets complicated when you have ATTR-CM because your body misinterprets what’s happening to your heart.

“ATTR-CM is what we call an infiltrative or restrictive cardiomyopathy,” Dr. Tang says. Imagine your heart muscle as a slingshot that gets less elastic over time. As your heart becomes stiffer, it can’t fill and pump blood as efficiently.

“Your kidneys notice that change, but they may think it’s a volume problem — that there’s not enough fluid circulating in your bloodstream because you’re dehydrated,” he continues. “They retain extra salt and water in response.”

When fluid builds up, it can make your heart failure symptoms worse than usual. In severe cases, you can develop fluid overload (hypervolemia). That amount of excess fluid can cause dangerous complications, like:

• Low blood pressure
• Fluid in your lungs
• Kidney problems

“When someone truly gets flooded with fluid, that’s often what prompts hospitalization,” Dr. Tang says.

While it’s less common, it’s also possible to have too little fluid and sodium (hypovolemia) with ATTR-CM. If that happens, it’s usually because of medication issues or because heat or illness has left you dehydrated.

“We don’t want you overloaded with fluid,” he adds. “But we don’t want you too dry either, because that can stress your kidneys.”

Signs your balance may be off

One of the keys to living well with ATTR-CM is learning to recognize the signs of a sodium and fluid imbalance before it gets bad.

“Many people can learn to recognize when their body feels ‘dry’ versus ‘wet,’” Dr. Tang says.

Signs of fluid buildup

Here are some of the key symptoms that your sodium and fluid levels are too high:

• Swelling (edema) in your belly, legs, ankles and feet
• Sudden weight gain
• A bloated or puffy feeling
• Increased shortness of breath
• Greater fatigue

“If your weight increases by a few pounds over two or three days — and it’s accompanied by symptom changes or visible swelling — that may be a sign of fluid retention,” Dr. Tang says.

Signs fluid levels are low

If you have ATTR-CM and your sodium and fluid levels get too low, you’ll probably notice symptoms like:

• A fast heart rate
• Low blood pressure
• Dizziness or fainting
• Sweating

Everyday habits to keep you on track

It isn’t always obvious that your sodium-fluid balance is off. Sometimes, the symptoms are subtle or build over time. That’s why many people with ATTR-CM monitor their health and daily behaviors carefully.

But the “how” can be a bit tricky.

“There’s no one-size-fits-all approach,” Dr. Tang reports. “Every person’s regimen is somewhat individualized.”

He walks us through the basics of managing sodium-fluid balance with ATTR-CM.

Track your sodium intake

Sodium helps control how much water your body holds onto. The goal is to keep the two in balance. So, when your sodium levels rise, your body may retain more fluid in response.

In ATTR-CM, the amount of sodium that’s safe to have in your diet varies from person to person. Your cardiologist will suggest a limit that makes sense for you, but Dr. Tang says 3 grams of salt a day is a common recommendation. (The average American eats nearly triple that.)

To keep sodium levels low, limit the number of highly processed foods you eat. That means reducing your intake of packaged foods and restaurant meals in favor of fresh, whole foods. If you’re trying to cut down, keeping a food diary can help.

Sodium restriction is a good idea, but it’s just part of a much larger picture. ATTR-CM is more complicated than that.

“It’s not just about the salt itself. It’s also about how your body is responding to and retaining fluid,” Dr. Tang clarifies. “What’s safe for you might not be safe for someone else.”

Follow fluid recommendations

Your provider will work with you to determine what fluid management looks like for you.

Some people need to actively restrict the amount of liquid they drink to avoid swelling. Other people just need to be mindful of it, to avoid going overboard.

Many people with ATTR-CM take diuretic medications to help keep their fluid levels from getting too high. Diuretics — also known as water pills — remove fluid by making you pee more than usual.

But fluid levels can change fast, so finding the right drug and dosage for you can be like trying to hit a moving target.

“The response to these drugs is very dynamic,” Dr. Tang explains. “It depends on the situation you’re in, other medications you’re taking, your illness and even how well your gut is absorbing the medicine.”

That’s why it’s crucial to alert your provider if you notice that you’re retaining more fluid than usual — and that you only adjust your medication in consultation with your doctor.

Check weight and swelling daily

As Dr. Tang puts it, “Fluid is weight.” So, weighing yourself daily is a great way to track fluid retention if you’re living with ATTR-CM. For the most accurate information, try to weigh yourself after you pee first thing in the morning.

To monitor your swelling:

• Check your feet, legs, ankles and abdomen every day.
• Notice how your clothing fits at the beginning of the day vs. the end of it.
• Gently press areas of visible swelling to see if your fingers leave a dent in the skin (pitting edema).

Whenever possible, track your weight and other indicators of excess fluid in the same symptom diary where you’re recording your salt intake.

When to call your doctor

Call your cardiologist’s office if:

• There’s a sudden or significant change in your symptoms.
• You’ve developed new symptoms.
• Your symptoms don’t seem to be responding to treatment.

“If your symptoms start or change very suddenly, rather than progressively, a more prompt in-person evaluation is needed,” Dr. Tang advises.

ATTR-CM is a serious heart condition. And sometimes it requires emergency care. Call 911 or local emergency services for signs of hyper- or hypovolemia, like:

• Difficulty breathing
• Extreme weakness
• Fainting (or feeling like you might faint)
• Sudden confusion
• Not being able to pee, or barely being able to pee

Dr. Tang warns that you may have to stay at the hospital to correct a severe fluid imbalance. But he’s quick to add that, while that can be a scary experience, it’s part and parcel of living with a chronic condition like ATTR-CM.

While they stabilize your condition, your provider will also work with your care team to figure out why your symptoms flared — and what to do about it.

“It’s not always just extra fluid causing sudden symptom changes,” he emphasizes. “Sometimes, there may be another issue going on, like a heart rhythm problem. It’s important to identify the cause and address it properly, with the right combination of medicines.”

Final thoughts

An ATTR-CM diagnosis can be overwhelming. And thinking about the ins and outs of managing sodium and fluid levels can be downright intimidating. The good news? You won’t do any of this work alone.

Researchers are learning more about ATTR-CM every day. And that means they’re getting better at crafting personalized fluid management plans. They’re also able to respond faster when circumstances change.

By working closely with your medical team, following their care plan and alerting them to any changes as they happen, you can feel more confident navigating daily life with ATTR-CM.