Prevalence of Pulmonary Embolism Among Emergency Department Patients With Syncope: A Multicenter Prospective Cohort Study

Thromboembolic Disease

Venous thromboembolism (VTE) encompasses deep vein thrombosis and pulmonary embolism, both of which can present on a spectrum from subtle symptoms to life- and limb-threatening emergencies. Some risk factors for VTE overlap cardiovascular risk factors and statin therapy can somewhat reduce the VTE risk. When presentations are not life-threatening, clinical prediction scores using the Well's criteria are best used to determine diagnostic testing. The mainstay of VTE treatment is anticoagulant therapy, although life- and limb-threatening presentations can also require thrombolytic therapy.

Case report: An elderly woman with recurrent syncope after pacemaker implantation

Syncope caused by atrioventricular block may occur as a result of a cardiac vasodepressor reflex. This article reports on a case of recurrent syncope in an 80-year-old woman with high-grade atrioventricular block, documented by electrocardiographic monitoring after pacemaker implantation. Pacemaker testing revealed stable impedance and sensing but a clear increase in the ventricular capture threshold at outputs. This case is unusual because the patient's primary diagnosis was non-cardiac. However, a combination of high D-dimer, hypoxemia, and computerized tomography scan of the pulmonary artery confirmed the diagnosis of pulmonary embolism (PE). With 1 month of anticoagulant therapy, the ventricular capture threshold gradually dropped to the normal range and syncope resolved. This is the first report of an electrophysiological phenomenon detected by pacemaker testing in a patient with syncope arising from PE.

Acute Pulmonary Embolism: A Review

IMPORTANCE

Pulmonary embolism (PE) is characterized by occlusion of blood flow in a pulmonary artery, typically due to a thrombus that travels from a vein in a lower limb. The incidence of PE is approximately 60 to 120 per 100 000 people per year. Approximately 60 000 to 100 000 patients die from PE each year in the US.

OBSERVATIONS

PE should be considered in patients presenting with acute chest pain, shortness of breath, or syncope. The diagnosis is determined by chest imaging. In patients with a systolic blood pressure of at least 90 mm Hg, the following 3 steps can be used to evaluate a patient with possible PE: assessment of the clinical probability of PE, D-dimer testing if indicated, and chest imaging if indicated. The clinical probability of PE can be assessed using a structured score or using clinical gestalt. In patients with a probability of PE that is less than 15%, the presence of 8 clinical characteristics (age <50 years, heart rate <100/min, an oxygen saturation level of > 94%, no recent surgery or trauma, no prior venous thromboembolism event, no hemoptysis, no unilateral leg swelling, and no estrogen use) identifies patients at very low risk of PE in whom no further testing is needed. In patients with low or intermediate clinical probability, a D-dimer level of less than 500 ng/mL is associated with a posttest probability of PE less than 1.85%. In these patients, PE can be excluded without chest imaging. A further refinement of D-dimer threshold is possible in patients aged 50 years and older, and in patients with a low likelihood of PE. Patients with a high probability of PE (ie, >40% probability) should undergo chest imaging, and D-dimer testing is not necessary. In patients with PE and a systolic blood pressure of 90 mm Hg or higher, compared with heparin combined with a vitamin K antagonist such as warfarin followed by warfarin alone, direct oral anticoagulants such as apixaban, edoxaban, rivaroxaban, or dabigatran, are noninferior for treating PE and have a 0.6% lower rate of bleeding. In patients with PE and systolic blood pressure lower than 90 mm Hg, systemic thrombolysis is recommended and is associated with an 1.6% absolute reduction of mortality (from 3.9% to 2.3%).

CONCLUSIONS AND RELEVANCE

In the US, PE affects approximately 370 000 patients per year and may cause approximately 60 000 to 100 000 deaths per year. First-line therapy consists of direct oral anticoagulants such as apixaban, edoxaban, rivaroxaban, or dabigatran, with thrombolysis reserved for patients with systolic blood pressure lower than 90 mm Hg.

Temporal trends in pulmonary embolism prevalence in Greece during 2013-2017

Background

Pulmonary embolism (PE) epidemiological data about the disease prevalence in the general population are unclear. The present study aims to investigate the prevalence of PE in Greece and the associated temporal trends for the years 2013–2017.

Methods

Data on medical prescriptions for PE in the years 2013–2017 were provided by the Greek National Health Service Organization (EOPYY). Data on age, gender, specialty of the prescribing physician and prescription unit were provided as well.

Results

The total number of medical prescriptions for PE for the study period was 101,426. Of the total prescriptions, 51% were issued by the Public Sector and 48% by the Private Sector. In 2013 the prevalence of PE was 5.43 cases per 100,000 citizens and increased constantly until 2017 with 23.79 cases per 100,000 population. Prevalence was higher in all years studied in the age group of 70–80 years. For the year 2017, we observed 69.35 cases per 100,000 population for subjects 70–80 years, followed by the ages 80–90 (60.58/100,000) and 60–70 years (56.47 /100,000). Females displayed higher PE prevalence than males and higher increasing trend.

Conclusion

PE prevalence has an increasing trend throughout the years 2013–2017 while prevalence in females is higher than males and displays a higher increasing trend. Our results may be used to appropriately organize nationwide health care campaigns aiming at the diagnosis, treatment and prevention of PE.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10621-2.

Syncope in pulmonary embolism: a retrospective cohort study

OBJECTIVE

To determine the prevalence of syncope or collapse in pulmonary embolism (PE).

METHODS

A retrospective cohort study was conducted. We examined the frequency with which syncope or collapse (presyncope) occurred alone or with other symptoms and signs in an unselected series of 224 patients presenting to a district general hospital with PE between September 2012 and March 2016. Confirmation of PE was by CT pulmonary angiogram in each case.

RESULTS

Our cohort of 224 patients comprised 97 men and 127 women, average age 66 years with age range of 21-94 years. Syncope or collapse was one of several symptoms and signs that led to a diagnosis of PE in 22 patients (9.8%) but was never the sole presenting feature. In descending order, these other clinical features were hypoxaemia (17 patients), dyspnoea (12), chest pain (9), tachycardia (7) and tachypnoea (7). ECG abnormalities reported to occur more commonly in PE were found in 13/17 patients for whom ECGs were available. Patients with PE presenting with syncope or collapse were judged to have a large clot load in 15/22 (68%) cases.

CONCLUSION

Syncope was a frequent presenting symptom in our study of 224 consecutive patients with PE but was never the sole clinical feature. It would be difficult to justify routine testing for PE in patients presenting only with syncope or collapse.

Patient-Level, Institutional, and Temporal Variations in Use of Imaging Modalities to Confirm Pulmonary Embolism

Background:

The choice of the imaging modality for diagnosis of pulmonary embolism (PE) could be influenced by provider, patient or hospital characteristics, or over time. However, little is known about the choice of the diagnostic modalities in practice. The aim of this study was to evaluate the variations in the use of imaging modalities for patients with acute PE.

Methods:

Using the data from Registro Informatizado Enfermedad TromboEmbolica (RIETE), a prospective international registry of patients with venous thromboembolism (March 2001–January 2019), we explored the imaging modalities used in patients with acute PE. The imaging modalities included computed tomography pulmonary angiography, ventilation/perfusion scanning, pulmonary angiography, a combination of these tests, or PE signs and symptoms plus imaging-confirmed proximal deep vein thrombosis but no chest imaging.

Results:

Among 38 025 patients with confirmed PE (53.1% female, age: 67.3±17 years), computed tomography pulmonary angiography was the dominant modality of diagnosis in all RIETE enrollees (78.2% [99% CI, 77.6–78.7]); including pregnant patients (58.9% [99% CI, 47.7%–69.4%]) and patients with severe renal insufficiency (62.5% [99% CI, 59.9–65.0]). A greater proportion of patients underwent ventilation/perfusion scanning in larger hospitals compared with smaller hospitals (13.1% versus 7.3%, P <0.001). The use of computed tomography pulmonary angiography varied between 13.3% and 98.3% across the countries, and its use increased over time (46.5% in 2002 to 91.7% in 2018, P <0.001).

Conclusions:

In a large multinational PE registry, variations were observed in the use of imaging modalities according to patient or institutional factors and over time. However, computed tomography pulmonary angiography was the dominant modality of diagnosis, even in pregnancy and severe renal insufficiency. The safety, costs, and downstream effects of these tests on PE-related and non-PE-related outcomes warrant further investigation.

Prevalence of pulmonary embolism in emergency department patients with isolated syncope: a prospective cohort study

BACKGROUNDS

Paramount to guide the diagnostic strategy, the prevalence of pulmonary embolism in patients with syncope and no other symptoms is uncertain. We aimed to assess the pulmonary embolism prevalence in patients that present to the emergency department (ED) with syncope and no chest pain nor dyspnea.

METHODS

Multicenter prospective cohort study in seven EDs in France. Adult patients who presented to the ED with syncope (transient loss of consciousness) were included. Patients with chest pain or dyspnea were excluded. Included patients underwent formal work-up for pulmonary embolism, including D-dimer testing and further imaging if positive. Cases of pulmonary embolism were adjudicated by two independent expert radiologists with the review of imaging studies. Secondary objectives included the pulmonary embolism prevalence in the subgroup of patients with cancer, in patients with negative Pulmonary Embolism Rule Out criteria (PERC) score, and according to the clinical probability assessed either by Wells or revised Geneva score.

RESULTS

We analyzed 411 patients, in whom 128 (31%) underwent a computed tomographic pulmonary angiogram and 9 (2%) a ventilation-perfusion scan. A pulmonary embolism was confirmed in nine patients (prevalence of 2.2%, 95% confidence interval, 1.1-4.3%), including one subsegmental pulmonary embolism. This prevalence was of 18% (3-52%) in patients with cancer and 0.7% (0.1-4%) in PERC negative patients.

CONCLUSION

In our sample of patients with isolated syncope, the prevalence of pulmonary embolism was 2.2%. This value is not sufficiently low to negate the requirement for a formal work up in the ED, even in the absence of chest pain or dyspnea. However, the large confidence interval precludes any strong conclusion.