Paradoxical Embolism Clinical Presentation

Updated: Aug 11, 2020
  • Author: Igor A Laskowski, MD; Chief Editor: Vincent Lopez Rowe, MD  more...
  • Print


The clinical findings of paradoxical embolism (PDE) are nonspecific and are related to other disease entities such as pulmonary embolism (PE), neurologic deficits associated with transient ischemic attack (TIA) or embolic stroke, and systemic arterial embolism. The clinical triad of PDE consists of the following:

  • Deep vein thrombosis (DVT), with or without PE
  • Intracardiac communication with a right-to-left shunt
  • Arterial embolism

Patients with normal hemodynamics and a patent foramen ovale (PFO) show no detectable abnormality in their medical history or on physical examination, chest roentgenography, or electrocardiography (ECG); however, patients with right atrial pressure elevated above the left atrial pressure tend to have right-to-left shunts and a predisposition to PDE. A PFO is the most frequent conduit for right-to-left shunts.

Patient symptoms can be exacerbated with Valsalva-type maneuvers, such as defecation, urination, and cough. Despite provocative maneuvers (eg, Valsalva or cough), left atrial pressure may remain higher than right atrial pressure, thereby preventing right-to-left shunting.

PDE is increasingly recognized as a cause of embolic stroke. [9] It is often a diagnosis of exclusion. DVT as an initial source of PDE must be ruled out clinically. A causative relationship exists among DVT, PFO, and ischemic neurologic events. Neurologic deficits in patients with cardiovascular events or DVT, PE, or any unexplained arterial embolism (eg, in the retinal artery, mesenteric artery, splenic artery, or renal artery) should be regarded with a high level of clinical suspicion for PDE. [10]

Symptoms associated with DVT may include the following:

  • Unilateral leg pain
  • Leg swelling – Swelling of one lower extremity is the most important clinical manifestation of lower-extremity DVT; generally, the swelling is painless; on palpation, the calf muscle is tender, and the Homan sign is present in fewer than one half of DVT cases
  • Unilateral leg redness – Redness is not seen in most cases of DVT but is almost always seen in superficial thrombophlebitis
  • A positive history of previous DVT – This is indicative because one third of all DVTs are recurrent

Symptoms associated with PE include the following:

  • Dyspnea
  • Chest pain
  • Hemoptysis
  • Syncope

Symptoms associated with embolic stroke include the following:

  • Unilateral weakness
  • Speech abnormality
  • Visual abnormality
  • Swallowing abnormality
  • Seizures

Symptoms associated with arterial embolism depend on the affected artery, which can supply any of the extremities or any of the major organs. Symptoms include the following:

  • Acute severe extremity pain
  • Paresthesia
  • Numbness
  • Skin discoloration
  • Inability to use the extremity

In the classic case of embolic occlusion of a lower-extremity artery (eg, the femoral or popliteal artery), the clinical picture can be summarized as the five Ps—that is, pain, pallor, pulselessness, paresthesia, and paralysis.

The clinical symptoms associated with multiorgan arterial embolism depend on the location of the embolism (eg, retinal artery, mesenteric artery, or splenic artery).


Physical Examination

Physical manifestations of PDE are related to DVT, PE, and manifestations of peripheral or central arterial embolism.

DVT can present physically with the following:

  • Unilateral leg swelling, tenderness, warmth, and erythema
  • Palpable cord along the course of the affected veins (possible)
  • Appearance of prominent venous collaterals (may be noted)

PE may present physically with the following:

  • Tachypnea
  • Hypotension
  • Central cyanosis
  • Tachycardia
  • Low-grade fever
  • Jugular venous distention
  • Accentuated pulmonic component of the second heart sound
  • New-onset atrial fibrillation (sometimes a subtle sign of PE)

Physical manifestations of cerebral embolism include the following:

  • Focal neurologic deficits that correspond to the areas of the cerebral cortex supplied by the affected artery
  • Facial weakness and visual neglect
  • Broca or Wernicke aphasia

Physical manifestations of acute arterial occlusion depend on the site, duration, and severity of the obstruction. They may include the following:

  • Pain
  • Coldness
  • Paralysis or motor weakness
  • Peripheral cyanosis or pallor
  • Loss of sensation

Intracardiac clot can lead to a new murmur, depending on the size and the location.



Complications of PDE include the following:

  • Neurologic deficit as a manifestation of stroke
  • Hemiplegia
  • Amaurosis fugax with eventual blindness
  • Motor aphasia
  • Seizure disorder complicating a cerebral insult
  • Arrhythmia, such as ventricular tachycardia or fibrillation (in cases of impending PDE)
  • Acute myocardial infarction (AMI) [11]
  • Loss of limb function with amputation
  • Organ damage (eg, renal infarction [12] )
  • Death