At an Internal Medicine Meeting 2017 session, “Approach to the Swollen Patient,” Viviana Navas, MD, offered attendees advice on accurately diagnosing heart failure.
“I get a lot of consults, and we love to call everything that has volume overload heart failure,” which is not always the case, said Dr. Navas, who is medical director of heart failure, cardiac transplantation, and mechanical circulatory support in the department of cardiology at the Cleveland Clinic in Weston, Fla.
She noted that other possible causes could include renal insufficiency, lymphedema, or cirrhosis. “We have to be clinicians and do a good physical exam,” she said. “Most of the time, I will say 80% of the time, just by good [history and physical] we should be able to diagnose a patient with true heart failure.”
Dyspnea and orthopnea are very common presenting symptoms, Dr. Navas said, but she also reminded physicians that “always, always, 100% of the time we have to ask about paroxysmal nocturnal dyspnea,” one of the first signs that a patient is accumulating fluid. “They tell you, ‘I cannot sleep. I keep waking up in the middle of the night.’ They don't know what it is, but usually it's because they just can't breathe.”
She also noted that patients with heart failure can present with gastrointestinal symptoms. “There is fluid that we don't really see,” she said. “[Patients may say,] ‘You know, I have a very poor appetite, I feel nauseous after I eat, early satiety.’ Those could all be symptoms of heart failure.”
On the physical exam, pay attention to the patient's general appearance, Dr. Navas said, since “most of these patients are usually distressed.” Vital signs usually include a low blood pressure, tachycardia, and pulsus alternans, a pulse that alternates strong and weak beats and usually happens in patients with severe left ventricular dysfunction. It's also important to look at the patient's neck for jugular venous distention (JVD), Dr. Navas said.
“Not everybody is going to have lower-extremity edema or ascites or something very visible on physical exam, but the JVD is usually there, and it's a very good form to diagnose volume overload in a patient without having to do any other type of invasive testing,” she said.
Dr. Navas noted that the S3 gallop is the most specific sign for heart failure, increasing likelihood by 11-fold. Patients with heart failure may have lung crackles, hepatomegaly, and ascites, and they may have edema of the extremities or extremities that are cold or warm to the touch, she noted.
Basic lab tests in patients who are volume overloaded will show often low sodium levels (below 135 mmol/L in 25% to 30%, Dr. Navas said), worsening renal function “from the volume accumulation and the poor perfusion that comes with heart failure,” elevated liver function tests, and anemia. Thyroid-stimulating hormone, urinalysis, and HbA1c should also be checked, she said.
Dr. Navas also discussed the role of B-type natriuretic peptide (BNP) and N-terminal pro B-type natriuretic peptide (NT-proBNP) in heart failure diagnosis. Current guidelines state that these values can help stratify risk in urgent care if clinical heart failure as a diagnosis is uncertain, she said. She pointed to the Breathing Not Properly Study, which found that a BNP cutoff of 100 pg/mL had a sensitivity of 90% and a specificity of 73% for diagnosis of heart failure in the ED, as well as an accuracy of 81.2% versus 74.0% for clinical judgment alone.
“It is useful, not just in the emergency room to try and differentiate, but I use it a lot to follow my patients,” she said. “When my patient is perfectly compensated and doing the best, and I think they have reached their dry weight, I check one [value], see what it is, and when they call me … and say ‘Doctor, I don't feel well,’ I check one and compare it. And it's usually pretty accurate in telling me when things are just not going well.”
Regarding imaging, the echocardiogram is the single most useful test in evaluating the etiology of heart failure, Dr. Navas said, but she also reminded attendees that it can be overused.
“We don't need an echocardiogram every time the patient gets admitted to the hospital,” she said. “If they had one echo within the last six months and nothing big has happened, like an acute MI or something like that, there is really no reason to repeat.”