Right heart failure (cor pulmonale): Clinical sciences

Right heart failure occurs when the right side of the heart cannot function properly, resulting in elevated central venous pressure and impaired pulmonary circulation. Assessing for right heart failure involves reviewing your patient's history and physical, lab results, performing an echocardiogram, and evaluating right and left heart catheterization findings. This helps to categorize it as right heart failure due to valvular disease, myocardial disease, or pulmonary hypertension. Keep in mind that right-sided heart failure secondary to pulmonary hypertension is also called cor pulmonale.

Now, if your patient presents with a chief concern suggesting right heart failure, perform an ABCDE assessment to determine if they’re unstable or stable. If unstable, stabilize their airway, breathing, and circulation, which might require endotracheal intubation and mechanical ventilation.

Next, obtain IV access and put them on continuous vital sign monitoring. Provide supplemental oxygen to maintain saturation above 90% and put your patient on cardiac monitoring. Finally, in some cases you might consider placing an indwelling pulmonary artery catheter, also known as a Swan-Ganz catheter, in order to obtain right sided filling pressures.

Next, obtain a focused history and physical examination. Your patient may report shortness of breath and chest pain, while physical exam might reveal hypotension, tachycardia, diaphoresis, and cold extremities. You might also notice jugular venous distention with hepatojugular reflux and lower extremity edema. Cardiac exam typically reveals a right ventricular heave, loud P2, and right-sided S3. At this point, you should suspect cardiogenic or obstructive shock due to right heart failure!

Here’s a clinical pearl! Cardiogenic shock could be due to an acute right ventricular myocardial infarction, acute right-sided valvular dysfunction, severe myocarditis, or cardiomyopathy. On the other hand, obstructive shock could result from a massive pulmonary embolism or cardiac tamponade.

Okay, next order, there is a variety of labs and imaging to obtain. Including a BNP, a standard 12-lead ECG and right-sided ECG, chest x-ray, echocardiogram, and if necessary, a CT pulmonary angiogram. Labs will likely show an elevated BNP.

ECG findings could show various findings like ST-elevation or depression; right axis deviation, right atrial enlargement, right ventricular hypertrophy, and arrhythmias. If there’s acute right heart strain, an S1Q3T3 pattern might be seen.

Chest x-ray often reveals a globular cardiac silhouette and potential rightward displacement, and if there’s also left heart failure, you might see pulmonary edema. Possible echocardiogram findings include right ventricular strain with hypertrophy or dilation, tricuspid or pulmonary valve dysfunction, and tamponade. CT pulmonary angiogram might reveal a pulmonary embolism. These findings confirm the diagnosis of cardiogenic or obstructive shock due to right heart failure.

Here’s a clinical pearl! Before diving into treatment, let’s quickly review a little myocardial physiology. When the right side of the heart is unable to pump enough blood to the lungs, it results in a buildup of blood in the right ventricle, leading to its overstretching. This in turn reduces left ventricular filling and preload.

You’ll see this in the setting of right-sided myocardial infarction. However, keep in mind other instances with high afterload, meaning the pressure the right heart has to pump against, like in pulmonary hypertension, PE, valvular disease, or COPD.

Okay first optimize RV preload! This might require the administration of IV fluids. The amount of which is largely dependent on the underlying cause. In the setting of a right sided myocardial infarction, you need to maintain preload in order to prevent worsening ischemia. So in this case increasing preload with IV fluids will increase cardiac output.

However, in other cases, like a massive PE, increasing preload with too much IV fluids will actually worsen the RV afterload, displacing the interventricular septum into the left ventricle causing immediate drop in cardiac output and cardiovascular collapse.

Use loop diuretics like furosemide, if diuresis is needed, like in pulmonary hypertension or valvular disease where the afterload is high. You should also encourage sodium and fluid restriction, and in some cases you might even need to provide ultrafiltration.

In order to help decrease PA afterload, you may also need to administer a pulmonary vasodilator, such as inhaled nitrous oxide. Next, to increase contractility and systemic blood pressure, give inotropes, like dobutamine and milrinone, and vasopressors, like norepinephrin. Sometimes, you may even need interventions like mechanical circulatory support like extracorporeal membrane oxygenation or ECMO. Finally, you must treat the underlying cause, like thrombolysis for massive pulmonary embolism or pericardiocentesis for tamponade.

Okay, let’s go back to the ABCDE assessment and now consider stable patients. First, obtain a focused history and physical exam. Your patient may report dyspnea on exertion, as well as abdominal fullness and early satiety.

Physical exam typically reveals jugular venous distention, possibly with positive hepatojugular reflux. You might also notice signs of fluid overload like bilateral lower extremity edema and even ascites.

Cardiac exam will likely reveal a right ventricular heave, loud P2, and right-sided S3. Importantly, there will not be evidence of pulmonary edema, thus differentiating it from left heart failure. At this point, you should suspect right heart failure!