Congestive heart failure: Clinical sciences

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Introduction0:00–0:31

Congestive heart failure, CHF, or the newer term, advanced heart failure, is a condition that occurs when the heart cannot pump or fill properly, leading to fluid accumulation in the lungs and other body tissues.
It is a leading cause of morbidity and mortality worldwide. Based on the side of the heart that is affected, CHF can be classified as right-sided or left-sided heart failure.Alright, the first thing to do when assessing a patient with signs and symptoms suggestive of CHF is to perform an ABCDE assessment to determine if they are stable or unstable.

History & Physical: Unstable0:31–4:10

If the patient is unstable, stabilize their airway, breathing, and circulation, which might require intubation. Additionally, obtain IV access, administer supplemental oxygen, and put your patient on continuous vital sign monitoring.OK, now that you’re done with acute management, obtain a focused history and physical exam, and order imaging, like Chest X-ray.
History typically reveals fatigue, shortness of breath, dyspnea on exertion, orthopnea, and paroxysmal nocturnal dyspnea.
On the flip side, a physical exam commonly reveals conversational dyspnea, rales, S3 heart sound, bilateral lower extremity edema, and jugular venous distention.
Finally, a chest X-ray might show an enlarged cardiac silhouette and evidence of pulmonary congestion, such as a “batwing” or “butterfly” appearance from alveolar edema and Kerley B lines from interstitial edema.Now, these findings should make you think of acute decompensated heart failure with pulmonary edema, so order B-type natriuretic peptide, or BNP for short; ECG; and a transthoracic echocardiogram, or TTE.
BNP greater than 400; ECG findings associated with arrhythmias or ischemia, as well as TTE findings of ventricular dysfunction and valve abnormalities support the diagnosis of acute decompensated heart failure with pulmonary edema.Alright, let’s switch gears to treatment.
First, treat the underlying cause whenever possible. For example, cardioversion for atrial fibrillation.
Next, treat symptoms of pulmonary congestion with loop diuretics, like furosemide, and IV vasodilators, such as hydralazine and nitrates, or you may even need positive inotropes, like dobutamine.
Here’s a high yield fact! Beta blockers should never be taken during acute decompensated heart failure, due to worsening congestion from their acute negative inotropic effects.
However, they can be given once the patient becomes euvolemic.Once you initiate the treatment, assess the patient’s response.
If there’s an adequate response, continue the current treatment until you can transition them to outpatient management. But, don’t forget the importance of lifestyle modifications, such as limiting sodium and fluid intake, as well as optimizing their chronic heart failure therapy.
However, if the response is inadequate and the patient is worsening, then you need to switch to advanced therapy. This might include procedures like ultrafiltration for diuresis; and circulatory support, like extracorporeal membrane oxygenation or ECMO as well as mechanical circulatory support or MCS such as a left ventricular assist device.
If the patient still fails to improve, consider a cardiac transplant.Now that unstable patients are taken care of, let’s go back to the ABCDE assessment and talk about stable ones.

Stable: Left heart failure4:10–10:27

When it comes to stable individuals, your first step is to obtain a focused history and physical, which will help determine if the CHF is left- or right-sided.
In left heart failure or LHF, the patient commonly reports symptoms related to lung congestion, such as orthopnea, paroxysmal nocturnal dyspnea, shortness of breath, and dyspnea on exertion.
There might be a past history of hypertension, cardiovascular disease, or valvular disease. Physical exam typically reveals elevated blood pressure, tachypnea, as well as conversational dyspnea, rales, and an S3 sound.
At this point, you should suspect left-sided heart failure, so your next step is to obtain labs, like BNP and CMP, ECG, as well as imaging, such as chest X-ray.
Most often, labs might show an elevated BNP, normal AST and ALT, and normal BUN and creatinine, which indicates normal renal function, but keep in mind that some patients may develop abnormal liver and kidney function tests.
Next, the ECG might demonstrate findings consistent with LHF such as left axis deviation, left atrial enlargement, and left ventricular hypertrophy; but also it might reveal precipitating factors, like ischemia.
Lastly, the chest X-ray typically shows an enlarged cardiac silhouette and pulmonary vascular congestion. If you see these findings, you should suspect left-sided heart failure.Alright, now that we’ve diagnosed LHF, let’s determine the type of dysfunction.
You can do this by using a TTE to calculate the left ventricle’s ejection fraction or EF for short. Now, if the EF is normal, meaning it’s equal to or greater than 50%, but there’s usually evidence of impaired relaxation, you can make the diagnosis of Heart Failure with preserved Ejection Fraction, or HFpEF for short, also known as diastolic or non-systolic heart failure.
Treatment includes minimizing risk factors and comorbidities, like optimizing blood pressure or treating arrhythmias; and medications to help control symptoms.
Some important medications include diuretics like furosemide; as well as beta-blockers, such as carvedilol, to optimize blood pressure.
Patients may also get either an ACE inhibitor or ACEi like lisinopril, an angiotensin receptor blocker or ARB like valsartan, or a combination angiotensin receptor/neprilysin inhibitor, or ARNI, which combines sacubitril and valsartan, and is actually preferred.
Mineralocorticoid receptor antagonists, or MRAs, like spironolactone, may also decrease hospitalization in patients with normal renal function and potassium levels.
These medications are known as Renin angiotensin aldosterone system inhibitors, also called RAAS inhibitors. They help control blood pressure and reduce their hospitalization frequency.
Finally, sodium-glucose cotransporter-2 inhibitors, or SGLT2i, such as dapagliflozin, help decrease mortality in HFpEF. Once again, individuals with CHF require close follow-up to assess their response to therapy.
If the patient’s response is adequate, continue the current treatment. However, if the response to therapy is inadequate, you should consider advanced therapy, such as ultrafiltration, circulatory support, or cardiac transplant.
Okay, let’s go back to TTE. Reduced EF of less than or equal to 40% and evidence of impaired contractility, are highly suggestive of Heart Failure with reduced Ejection Fraction or HFrEF for short, also known as systolic heart failure.
As in HFpEF, your first management step for HFrEF is minimizing risk factors and comorbidities. Additionally, five classes of medications should be started, including diuretics like furosemide to control symptoms; beta blockers like carvedilol, to regulate BP and reduce mortality; as well as SGLT2i like dapagliflozin; plus an ACEi like lisinopril or an ARB like valsartan, or an ARNI like sacubitril/valsartan, which is preferred; and an MRA like spironolactone, which reduce mortality.
Lastly, some patients may get digoxin, which doesn’t reduce mortality, but helps control symptoms and decrease hospitalization.Here’s a high-yield fact!
You should avoid certain medications in patients with CHF, such as thiazolidinediones, which might increase fluid retention; and calcium channel blockers, whose negative inotropic effects worsen heart failure, especially the systolic type.
Once again, individuals with CHF require close follow-up to assess their response to therapy. If the response is adequate, continue the current treatment.
However, if the response is inadequate, you should consider an implantable cardioverter-defibrillator if their EF is 35% or less.
As a last resort, if nothing else works, consider more advanced therapy, such as ultrafiltration, circulatory support, or cardiac transplantNow that we are done with left-sided heart failure, let’s discuss right heart failure or RHF.

Stable: Right heart failure10:27–14:14

These individuals might report shortness of breath, dyspnea on exertion, and a possible history of pulmonary disease, valvular heart disease, or LHF.
Physical exam typically reveals cyanosis, tachypnea, holosystolic murmur, and an S3 heart sound. Additionally, the exam can show signs of systemic congestion, such as JVD, ascites, hepatosplenomegaly, and bilateral lower extremity edema.
If you see this, you should suspect RHF.Now, here’s a high-yield fact! The most common cause of RHF is LHF.
When both sides of the heart are affected, it’s called biventricular failure, which is associated with signs and symptoms of both types.
Alright, once you suspect RHF, proceed with labs, including BNP and CMP; ECG; and chest X-ray. Once again, the BNP will likely be elevated.
However, unlike LHF, the CMP will commonly reveal elevated AST and ALT, and increased BUN and creatinine. Additionally, the ECG typically reveals right axis deviation, right atrial enlargement, and right ventricular hypertrophy, as well as possible ischemia or arrhythmia.
Finally, important chest X-ray findings include a globular cardiac silhouette with rightward displacement and increased interstitial markings.
All of this supports your diagnosis of RHF. Once you have diagnosed RHF, proceed with TTE to identify whether there is an underlying structural disease; or if the pulmonary artery systolic pressure is elevated.
If TTE reveals a structural abnormality, such as tricuspid regurgitation, it suggests that the RHF is secondary to valvular disease.
Treatment typically requires O2 supplementation; loop diuretics, like furosemide; and treatment of the underlying cause, which often requires consultations with your surgery team.
Here’s a high yield fact! Occasionally, a patient with acute decompensated biventricular heart failure may develop acute kidney injury, or AKI, which might lead you to think that you can't give them diuretics.
However, in this case, their creatinine will actually get better by decreasing the systemic congestion with diuretics, so go ahead and diurese them anyway.On the other hand, if TTE reveals an elevated pulmonary artery systolic pressure, or PASP, of 25 mmHg or higher, it’s consistent with RHF secondary to pulmonary artery hypertension or PAH.
PAH has multiple causes, such as LHF and cor pulmonale from chronic lung disease. Treatment typically requires O2 supplementation, loop diuretics, like torsemide, and treatment of the underlying cause.
As before, close follow-up is required. If there’s an adequate response, continue the current treatment.
However, if there’s an inadequate response, proceed with an implantable cardioverter-defibrillator if indicated, and as a last resort, advanced therapy like ultrafiltration, circulatory support, or cardiac transplant.Alright, as a quick recap… To diagnose heart failure, you’ll need to obtain labs like BNP and CMP, ECG, and an X-ray.

Review14:14–15:27

Unstable patients usually have pulmonary edema next to HF, so be sure to treat them with diuretics, inotropes, and vasodilators.
Patients who don’t respond to treatment require ultrafiltration, circulatory support, and a possible cardiac transplant.
When it comes to stable patients with left-sided HF, they should be assessed with TTE. HFpEF is treated with diuretics and SGLT2 inhibitors and possible beta blockers, RAAS inhibitors, and MRAs.
On the flip side, HFrEF should be treated with the same medications and additionally vasodilators and digoxin. When it comes to right-sided HF, you should also use TTE to assess the patient.
Patients with right-sided HF require supplemental oxygen and diuretics. You should also treat the underlying cause, which means that you might need to consult the surgical team if the patient has any underlying structural abnormalities.
Congestive heart failure: Video, Anatomy, Function | Osmosis