Syncope as an Emergency Department Presentation of Pulmonary Embolism

doi:10.1016/S0736-4679(97)00228-X

The Journal of Emergency Medicine

Volume 16, Issue 1, January–February 1998, Pages 27-31

https://doi.org/10.1016/S0736-4679(97)00228-X Get rights and content

Abstract

Pulmonary embolism presenting as an isolated syncopal spell can be a difficult clinical correlation to make. We present three cases of pulmonary embolism-induced syncope and review the pathophysiology and diagnostic considerations in this setting. Pulmonary embolism should be considered in the differential diagnosis of every syncopal event that presents to the emergency department, even in the face of cardiac dysrhythmias and normal pulse oximetry values.

Introduction

Recognized venous thromboembolism (pulmonary embolism and deep venous thrombosis) is responsible for more than 250,000 hospitalizations and approximately 50,000 deaths per year in the United States [1]. Because it is difficult to diagnose, the true incidence of pulmonary embolism is unknown, but is estimated to be around 650,000 cases annually [2]. Despite this high incidence, the diagnosis of pulmonary embolism continues to be elusive, primarily because of its notorious vagaries of symptoms and signs. Syncope, on the other hand, is a relatively easy clinical symptom to detect, but has an almost bewildering array of etiologies that led to a documented cause in only 58% of syncopal events in one large prospective series [3].

Syncope as the presenting symptom of pulmonary embolism can prove to be a difficult clinical correlation to make. We present three cases of pulmonary embolism-induced syncope and review the pathophysiology and diagnostic considerations in this setting.

Section snippets

Case 1

A 53-year-old man was jogging when he suddenly felt light-headed. He stopped, controlled his fall, and then had a brief loss of consciousness. Shortly thereafter, he signaled a passing car for help and paramedics responded to the scene. He felt well and denied any ongoing symptoms when he arrived in the emergency department. Further questioning revealed a several day history of nonproductive cough, for which he had been prescribed penicillin, and a history of tachycardia of unknown etiology 6

Case 2

A 38-year-old man was walking into his bathroom when he felt dizzy. His wife, who witnessed the event, reported that he sat down, shook his head, and was unresponsive for 20 s. She then called the paramedics. Upon their arrival, the patient was completely alert and oriented and denied any continuing symptoms. Medical history was significant only for hypertension, for which he took diltiazem, atenolol, and chlorthalidone. Vital signs were: blood pressure of 132/100 mmHg, pulse rate of 100

Case 3

A 34-year-old woman who was 8 weeks pregnant by in vitro fertilization was walking near the hospital when she noted sudden onset of light-headedness and blurred vision followed by a syncopal spell. She rested for a short time, then walked to the emergency department. In the emergency department, she complained of mild chest heaviness accompanied by the sensation of a pounding heart. She denied dyspnea, pleuritic chest pain, leg pain or swelling, vaginal bleeding or cramping, abdominal pain, or

Discussion

Pulmonary embolism is a frequent cause of death in the United States 1, 2. Despite this, the diagnosis of pulmonary embolism remains difficult to make. The classic triad of pleuritic chest pain, dyspnea, and hemoptysis is rare in large studies of pulmonary embolism 4, 5, and clinically apparent DVT was present in only 11% of confirmed cases of pulmonary embolism in PIOPED patients without underlying cardiopulmonary disease [5]. Karwinski and Svendsen found that 81% of pulmonary embolisms

Conclusions and Recommendations

This case series was written to review the entity of pulmonary embolism-induced syncope and to encourage clinicians to consider pulmonary embolism in every syncope patient. We have presented three cases to demonstrate the subtleties of these patients’ presentations. Often, patients with pulmonary embolism and syncope will present after the clot has dispersed and will be relatively asymptomatic.

Once considered, the following findings in combination with a history of syncope should lead to

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Cited by (38)

The Prognostic Value of Syncope on Mortality in Patients With Pulmonary Embolism: A Systematic Review and Meta-analysis
2020, Annals of Emergency Medicine
Citation Excerpt :
It is unclear to what extent this may have played a role in the present study because neither intracranial bleeding nor head trauma was mentioned in the included studies. Nonetheless, the associations we found in our main analysis are physiologically plausible because mechanisms underlying syncope in pulmonary embolism are associated with short-term mortality, hemodynamic instability, and older age.8,52-54 In patients with acute pulmonary embolism, syncope is associated with a 4% (95% CI 1% to 8%) higher short-term mortality (OR 1.82; 95% CI 1.14 to 2.90) and a 12% (95% CI 7% to 18%) higher prevalence of hemodynamic instability (OR 4.36; 95% CI 2.27 to 8.37).
Syncope is a presenting symptom in 10% to 20% of patients with pulmonary embolism. We perform a meta-analysis to clarify the prognostic value of syncope on short-term mortality in pulmonary embolism patients and its association with hemodynamic instability.
PubMed, EMBASE, and the Cochrane Library were searched up until January 7, 2020. Studies reporting inhospital or 30-day mortality of adults with pulmonary embolism with and without syncope were included. Quality of included studies was evaluated with the Quality in Prognosis Studies tool. Meta-analysis was conducted to derive pooled odds ratios (ORs) and risk differences for the relation of syncope with mortality and hemodynamic instability. To study the influence of hemodynamic instability on the association between syncope and mortality, meta-regression was performed.
Search and selection resulted in 26 studies, of which 20 were pooled, involving 9,419 of 335,120 patients (3%) with syncope. Syncope was associated with higher mortality (OR 1.82; 95% confidence interval [CI] 1.14 to 2.90; I² 88%; risk difference 4% [95% CI 1% to 8%]) and higher prevalence of hemodynamic instability (OR 4.36; 95% CI 2.27 to 8.37; I² 93%; risk difference 12% [95% CI 7% to 18%]). OR for mortality in patients with pulmonary embolism with syncope versus without it was higher in the presence of a larger difference in hemodynamic instability between groups (coefficient 0.05; 95% CI 0.01 to 0.09).
The association between syncope and short-term mortality in patients with pulmonary embolism is explained by a difference in hemodynamic instability. This emphasizes the importance of risk stratification by hemodynamic status in pulmonary embolism patients with and without syncope.
Pearls and Myths in the Evaluation of Patients with Suspected Acute Pulmonary Embolism
2019, American Journal of Medicine
Citation Excerpt :
Conversely, <2% of patients presenting with syncope have a concomitant diagnosis of pulmonary embolism.24 Possible explanations for a syncopal event in the context of pulmonary embolism include acute right heart failure by a sudden increase in ventricular overload with consecutively reduced cardiac output (cardiac syncope), or, alternatively, a pressure-induced vagal stimulation with reflex bradycardia (vagal syncope).25,26 In either setting, a massive centrally located embolus that affects pulmonary hemodynamics must be assumed as a causative factor.
Significant improvement has been achieved in diagnostic accuracy, validation of probability scores, and standardized treatment algorithms for patients with suspected acute pulmonary embolism. These developments have provided the tools for a safe and cost-effective management for most of these patients. In our experience, however, the presence of medical myths and ongoing controversies seem to hinder the implementation of these tools in everyday clinical practice. This review provides a selection of such dilemmas and controversies and discusses the published evidence beyond them. By doing so, we try to overcome these dilemmas and suggest pragmatic approaches guided by the available evidence and current guidelines.
Superior vena cava syndrome complicated with acute pulmonary thromboembolism in a patient with lung cancer
2018, Journal of Cardiology Cases
Citation Excerpt :
Pulmonary embolism is a frequent cause of death in the USA but it remains difficult to be diagnosed. Pulmonary emboli differ considerably in sizes, locations, and the underlying disorders, including malignancy, trauma, and protein C or S deficiency, etc [1]. A triad of pleuritic chest pain, dyspnea, and hemoptysis may occur simultaneously.
Thrombosis involving the subclavian vein and superior vena cava is relatively common, especially in cancer patients. Edema of the arms and head is a well-known clinical consequence of this thrombosis. The intrinsic risk of pulmonary embolism has not been reported previously. Herein, we describe the case of a 63-year-old male patient with extensive stage small cell lung cancer who developed superior vena cava syndrome. Pulmonary thromboembolism was complicated after receiving systemic chemotherapy and localized radiotherapy.
<Learning objective: Superior vena cava (SVC) syndrome may pose a significant risk factor of pulmonary thromboembolism. Although SVC syndrome and pulmonary thromboembolism may have similar comorbidities, pulmonary thromboembolism might occur after treatment of SVC syndrome. Possible mechanisms may be related to tumor debris and hypercoagulable central vein thrombosis. Physicians must be vigilant with patients whom have dyspnea after treatment of SVC syndrome. Computed tomography angiography may help make an early diagnosis if clinical suspicion is made.>
Pulmonary Embolism Inpatients Treated With Rivaroxaban Had Shorter Hospital Stays and Lower Costs Compared With Warfarin
2016, Clinical Therapeutics
Citation Excerpt :
Pulmonary embolism (PE) is a common and sometimes fatal form of venous thromboembolism (VTE). An estimated 650,000 individuals are affected in the United States each year, with approximately 20% to 25% mortality within the first day of diagnosis and >10% at mortal risk during the first month after diagnosis, imposing a substantial economic burden on the US health care system, with estimated annual costs exceeding $1.5 billion.1–3 Clinical practice treatment guidelines recommend short-term treatment with parenteral anticoagulants, such as low-molecular-weight heparin, fondaparinux, or unfractionated heparin, either alone or with an oral vitamin K antagonist (VKA).4
Using real-world data, this study compares inpatient length of stay (LOS) and costs for patients with a primary diagnosis of pulmonary embolism (PE) initiating treatment with oral anticoagulation with rivaroxaban versus warfarin.
Hospitalizations from MarketScan’s Hospital Drug Database were selected from November 1, 2012, through December 31, 2013, for adults with a primary diagnosis of PE initiating treatment with rivaroxaban or warfarin. Warfarin patients were matched 1:1 to rivaroxaban patients using exact and propensity score matching. Hospital LOS, treatment patterns, and hospitalization costs were evaluated.
Matched cohorts included 751 rivaroxaban-treated patients and 751 warfarin-treated patients. Adjusted mean LOS was 3.77 days for rivaroxaban patients (95% CI, 3.66–3.87 days) and 5.48 days for warfarin patients (95% CI, 5.33–5.63 days; P < .001). Mean (SD) LOS was shorter for patients taking rivaroxaban whether admission was for provoked PE (rivaroxaban: 5.2 [5.1] days; warfarin: 7.0 [6.5] days; P < .001) or unprovoked PE (rivaroxaban: 3.4 [2.3] days; warfarin: 5.1 [2.7] days; P < .001). Mean (SD) days from first dose to discharge were 2.5 (1.7) (rivaroxaban) and 4.0 (2.9) (warfarin) when initiated with parenteral anticoagulants (P < .001) and 2.7 (1.7) (rivaroxaban) and 4.0 (2.2) (warfarin) without parenteral anticoagulants (P < .001). The rivaroxaban cohort incurred significantly lower unadjusted mean (SD) hospitalization costs (rivaroxaban: $8473 [$9105]; warfarin: $10,291 [$9185]; P < .001), confirmed by covariate adjustment with generalized linear modeling estimating predicted mean hospitalization costs of $8266 for rivaroxaban patients (95% CI, $7851–$8681) and $10,511 for warfarin patients (95% CI, $10,031–$10,992; P < .001).
patients with PE treated with rivaroxaban incurred significantly lower hospitalization costs by $2245 per admission compared with patients treated with warfarin, which was attributable to cost offsets from 1.71 fewer days of stay in the hospital.
A New Approach to the Diagnosis of Acute Dizziness in Adult Patients
2016, Emergency Medicine Clinics of North America
Citation Excerpt :
Among 15 dangerous causes analyzed, the most commonly recorded were fluid and electrolyte disturbances (5.6%), cerebrovascular diseases (4.0%), cardiac arrhythmias (3.2%), acute coronary syndromes (1.7%), anemia (1.6%), and hypoglycemia (1.4%).2 Some dangerous causes of dizziness, such as adrenal insufficiency,8 aortic dissection,9 carbon monoxide intoxication,10 pulmonary embolus,11 and thiamine deficiency,12 are treatable causes that are important but rare.2 How does this study compare to others?
Prevalence of pulmonary embolism in syncope patients
2018, Canadian Journal of Emergency Medicine

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Clinical CommunicationSyncope as an Emergency Department Presentation of Pulmonary Embolism

Abstract

Introduction

Section snippets

Case 1

Case 2

Case 3

Discussion

Conclusions and Recommendations

Prog Cardiovasc Dis

Am J Med

Chest

Chest

Arch Phys Med Rehabil

Arch Phys Med Rehabil

J Emerg Med

Am J Med

Am Heart J

Chest

Am J Med

Clinical Communication
Syncope as an Emergency Department Presentation of Pulmonary Embolism