Pulsus paradoxus is a common cardiac and pulmonary condition that is marked by a dramatic decrease in blood pressure. Pulsus paradoxus symptoms are commonly seen with heart and lung diseases, such as pulmonary embolism or cardiac tamponade. But other conditions can also cause pulsus paradoxus.
Affected patients typically exhibit Beck’s triad, a pattern of abnormally distant heart sounds, along with other signs of tamponade. Pulsus paradoxus can also be accompanied by pericardial effusion, which is an accumulation of fluid in the pericardium. The presence of pulsus paradoxus can help physicians diagnose cardiac tamponade.
In the case of a cardiac tamponade, the heart is squeezed by a buildup of fluid. If left untreated, this condition can lead to a life-threatening complication. Symptoms include a drop in blood pressure, a heartbeat that is too fast or weak, and shortness of breath. This is caused by a lack of oxygen in the blood. Other conditions that can cause pulsus paradoxus are chronic obstructive pulmonary disease (COPD) and severe asthma.
Often, pulsus paradoxus is the result of a pericardial disease, such as constrictive pericarditis, which can lead to scarring and a thickening of the pericardium. When this happens, the pericardium becomes very thick, which can press down on the heart. As a result, a change in systolic and diastolic pressures occurs. Generally, the changes are exaggerated.
In the absence of pericardial disease, pulsus paradoxus is typically not detectable, because the blood pressure is normal. However, the severity of a pulsus paradoxus can be evaluated by measuring the systolic and diastolic differences between the two phases of inspiration and expiration. This measurement should be taken using a manual stethoscope. Usually, this can be done as part of a routine physical exam.
If a patient presents with pulsus paradoxus, they should be assessed by an interprofessional team, including a doctor, nurses, and cardiologist. The team should be able to identify the underlying pathology, so that treatment can be targeted at the underlying issue. Treatment may include surgery, medications, and/or CVP.
Depending on the etiology of pulsus paradoxus, the patient may be monitored by a catheter in the artery. It is important to note that automatic blood pressure cuffs cannot accurately measure pulsus paradoxus.
If a patient has pulsus paradoxus, their doctor will probably perform an echocardiogram. A physician will also check for underlying cardiac or lung diseases. They can perform chest radiography to look for hemodynamic compromise. Another possible indication of a pulsus paradoxus etiology is the presence of a pleural effusion. Pleural effusion is a buildup of fluid in the pleura, the thin layer that lines the lungs and chest wall. Normally, the pleura is only thick enough to support a few liters of fluid.
Usually, pulsus paradoxus is not a cause for concern, but if it occurs, it can be a sign of a serious condition. Patients who have pulsus paradoxus are at risk for a pulmonary embolism, which is a potentially life-threatening condition that occurs when a blood clot in a lung artery breaks free, travels to the aorta, and occludes the flow of blood.
