According to the medical experts, one of the possible consequences of the novel coronavirus infection is the formation of blood clots. That makes this a good time to discuss pulmonary embolism, one of the more frequent causes of death resulting from misdiagnosis.

Pulmonary Embolism, Illustration - Stock Image - C027/7044 ...

It is reliably reported, and consistent with what I have seen in over 40 years of trying medical malpractice cases, that misdiagnosis is one of the leading causes of medical malpractice. Two of the most common misdiagnoses involve myocardial infarctions (heart attacks) and pulmonary embolism. These are certainly the two most common I have seen in my work.

Pulmonary embolism and myocardial infarction have some things in common that make them cases I can bring on behalf of a patient, or more likely, the patient’s surviving family members. In the first place, when their presence is missed by the treating health care provider, they can be, and often are, fatal. Secondly, while they have what are called “classic presentations” that most doctors or other health care providers would promptly recognize, they can also have atypical presentations that are harder to identify. The cases I see are usually atypical presentations.

A pulmonary embolism is a blood clot or a group of blood clots that find their way to the lungs and block blood flow through the lungs. If the clot is large enough, it can kill the patient in a matter of minutes. If it is small enough, it will have no effect and may never be noticed by the patient. However, even if clots are small, if there are enough of them, they can block off enough of the blood flow through the lungs to kill the patient.

We have two forms of circulation in our bodies. One is the venous circulation in which the oxygen poor blood is returned to the heart and then the lungs, where it exchanges its carbon dioxide for oxygen. The freshly oxygenated blood is then returned to the heart where it enters the arterial circulation. The arterial circulation then sends the oxygen rich blood to all the parts of the body.

Pulmonary emboli are creatures of the venous circulation. A clot develops in a vein, most often in the deep circulation of the leg. This is usually called a Deep Venous Thrombosis or DVT. The clot or a piece of the clot breaks free and is carried along with the venous blood to the right side of the heart. The right ventricle of the heart then pumps the venous blood and the clot into the pulmonary artery, which carries them to the lungs. Once in the lungs, the venous blood is pushed into progressively smaller vessels. The carbon dioxide/oxygen exchange takes place in alveoli, which are almost microscopically small. If a clot is present, the clot will get stuck when it can no longer fit through a vessel in the lung. When the clot gets stuck, it acts as a dam and prevents blood from getting to where it needs to go to be reoxygenated. If the clot is small, it will block off only a small portion of the lung. However, the larger the clot, the sooner it will get stuck and the greater amount of lung circulation it will block. Many small clots in the lung can have the same blocking effect as one very large clot. Many small clots can block off so much lung that the lungs cannot supply enough oxygen to sustain life.

A clot in the deep veins of the leg may produce pain, tenderness and swelling in the leg. If the clot produces these symptoms, it makes the problem much easier to diagnose. A non-invasive ultrasound of the leg will usually show the presence of the clot and the patient will receive some sort of blood thinner to prevent further clot formation and to allow the body to dissolve the clot. The clot may not produce any symptoms in the leg, however. Then the problem becomes harder to diagnose.

Once the clots reach the lung, and assuming they are not so large that they kill the patient right away, they can cause the following symptoms:

Shortness of breath that may occur suddenly.

Sudden, sharp chest pain that may become worse with deep breathing or coughing.

Rapid heart rate.

Rapid breathing.



Coughing up blood or pink, foamy mucus.


These are the classic signs and symptoms of pulmonary embolism. If these signs and symptoms are all present and if they appear suddenly and are pronounced, they make the diagnosis much easier. In the cases I often see, however, the symptoms are more gradual, only some of them are present and the whole thing looks like the flu or a chest cold. When the symptoms appear gradually and look like the flu or a chest cold, it is much easier for a doctor or other health care provider to mistake the pulmonary embolism for some more benign condition, such as the flu or a cold and send the patient home.

If you have difficulty breathing, shortness of breath, fatigue, fast heart rate, get to an emergency department and don’t delay. It may be the coronavirus, it may be pulmonary embolism, or it may be nothing. Don’t take a chance. Get examined and tested. There are tests which can rule in or rule out a pulmonary embolism. Let the medical professionals decide what, if anything, is wrong with you.