Syncope and PE

I agree with these comments with this caveat: We are over evaluating and over-diagnosing PE in patients with pleuritic CP and unexplained dyspnea as this is the most common presentation and is what most clinicians consider symptomatic for PE. Yet these presentations generally do not lead to bad outcomes even if the diagnosis is missed. PE causing syncope, however, is very dangerous and has a relatively higher mortality of missed. Furthermore, PE from a large clot causing syncope often causes NEITHER dyspnea nor pleurisy nor hypoxia (most of the clot is too proximal to cause distal necrosis, inflammation or affect oxygen exchange). You may also find cardiac changes such as A-fib or orthostasis and tachycardia and may misinterpret the cause of syncope to be of primary cardiac origin. To me this paper reminds all of us to always consider PE to be a cause of syncope - at least let this diagnosis enter your mind and be considered - since this is the patient who may die if you miss the diagnosis and these patients generally do not have the more classic symptoms of pleurisy or dyspnea. Yes - once considered it often is readily apparent in the fact they usually are tachycardic and have S1Q3T3 changes but these might not be appreciated if you do not consider PE in every syncope case.