Diagnosis of acute thoracic aortic dissection in the emergency department

Mortality and risk factors associated with misdiagnosis of acute aortic syndrome in Ontario, Canada: a population-based study

INTRODUCTION

Acute aortic syndrome (AAS) is a life-threatening aortic emergency. It describes three diagnoses: acute aortic dissection, acute intramural haematoma and penetrating atherosclerotic ulcer. Unfortunately, there are no accurate estimates of the miss rate for AAS, risk factors for missed diagnosis or its effect on outcomes.

METHODS

A population-based retrospective cohort study of anonymously linked data for residents of Ontario, Canada, was carried out. Incident cases of AAS were identified between 2003 and 2018 using a validated algorithm based on ICD codes and death. Before multivariate modelling, all categorical variables were analysed for an association with missed AAS diagnosis using χ2 tests. These preliminary analyses were unadjusted for clustering or any covariates. Finally, we performed multilevel logistic regression analysis using a generalised linear mixed model approach to model the probability of a missed case occurring.

RESULTS

There were 1299 cases of AAS (age mean (SD) 68.03±14.70, woman 500 (38.5%), rural areas (n=111, 8.55%)) over the study period. Missed cases accounted for 163 (12.5%) of the cohort. Mortality (non-missed AAS 59.7% vs missed AAS 54.6%) and surgical intervention (non-missed AAS 31% vs missed AAS 30.7%) were similar in missed and non-missed cases. However, lower acuity (Canadian triage acuity scale >2 (OR 2.45 95% CI 1.71 to 3.52) (the scale is from 1 to 5, with 1 indicating high acuity) had a higher odds of being a missed case and non-ambulatory presentation (OR 0.47 95% CI 0.33 to 0.67) and presenting to a teaching (OR 0.60 95% CI 0.40 to 0.90)) or cardiac centre (OR 0.41 95% CI 0.27 to 0.62) were associated with a lower odds of being a missed case.

CONCLUSIONS

The high rate of misdiagnosis has remained stable for over a decade. Non-teaching and non-cardiac hospitals had a higher incidence of missed cases. Mortality and rates of surgery were not associated with a missed diagnosis of AAS. Educational interventions should be prioritised in non-teaching hospitals and non-cardiac centres.

The sonographic protocol for the emergent evaluation of aortic dissections (SPEED protocol): A multicenter, prospective, observational study

OBJECTIVES

An aortic dissection (AoD) is a potentially life-threatening emergency with mortality rates exceeding 50%. While computed tomography angiography remains the diagnostic standard, patients may be too unstable to leave the emergency department. Investigators developed a point-of-care ultrasound (POCUS) protocol combining transthoracic echocardiography (TTE) and the abdominal aorta. The study objective was to determine the test characteristics of this protocol.

METHODS

This was an institutional review board-approved, multicenter, prospective, observational, cohort study of a convenience sample of adult patients. Patients suspected of having an AoD received a TTE and abdominal aorta POCUS. Three sonographic signs suggested AoD: a pericardial effusion, an intimal flap, or an aortic outflow track diameter measuring more than 35 mm. Investigators present continuous and categorical data as medians with interquartile ranges or proportions with 95% confidence intervals (CIs) and utilized standard 2 × 2 tables on MedCalc (Version 19.1.6) to calculate test characteristics with 95% CI.

RESULTS

Investigators performed 1314 POCUS examinations, diagnosing 21 Stanford type A and 23 Stanford type B AoD. Forty-one of the 44 cases had at least one of the aforementioned sonographic findings. The protocol has a sensitivity of 93.2% (95% CI 81.3-98.6), specificity of 90.9 (95% CI 89.2-92.5), positive and negative predictive values of 26.3% (95% CI 19.6-33.9) and 99.7% (95% CI 99.2-100), respectively, and an accuracy of 91% (95% CI 89.3-92.5).

CONCLUSIONS

The SPEED protocol has an overall sensitivity of 93.2% for AoD.

[Acute aortic syndrome]

Acute aortic syndrome embraces a group of heterogenous pathological entities involving the aortic wall with a common clinical profile. The current epidemiology, clinical presentation, diagnosis and treatment strategy are discussed in this review. Besides, the importance of multidisciplinary aortic teams, aortic centers and the implementation of an aortic code are emphasized.

Evaluation of the Canadian Clinical Practice Guidelines Risk Prediction Tool for Acute Aortic Syndrome: The RIPP Score

Introduction

Acute aortic syndrome (AAS) is a rare clinical syndrome with a high mortality rate. The Canadian clinical practice guideline for the diagnosis of AAS was developed in order to reduce the frequency of misdiagnoses. As part of the guideline, a clinical decision aid was developed to facilitate clinician decision-making (RIPP score). The aim of this study is to validate the diagnostic accuracy of this tool and assess its performance in comparison to other risk prediction tools that have been developed.

Methods

This was a historical case-control study. Consecutive cases and controls were recruited from three academic emergency departments from 2002-2020. Cases were identified through an admission, discharge, or death certificated diagnosis of acute aortic syndrome. Controls were identified through presenting complaint of chest, abdominal, flank, back pain, and/or perfusion deficit. We compared the clinical decision tools' C statistic and used the DeLong method to test for the significance of these differences and report sensitivity and specificity with 95% confidence intervals.

Results

We collected data on 379 cases of acute aortic syndrome and 1340 potential eligible controls; 379 patients were randomly selected from the final population. The RIPP score had a sensitivity of 99.7% (98.54-99.99). This higher sensitivity resulted in a lower specificity (53%) compared to the other clinical decision aids (63-86%). The DeLong comparison of the C statistics found that the RIPP score had a higher C statistic than the ADDRS (-0.0423 (95% confidence interval -0.07-0.02); P < 0.0009) and the AORTAs score (-0.05 (-0.07 to -0.02); P = 0.0002), no difference compared to the Lovy decision tool (0.02 (95% CI -0.01-0.05 P < 0.25)) and decreased compared to the Von Kodolitsch decision tool (0.04 (95% CI 0.01-0.07 P < 0.008)).

Conclusion

The Canadian clinical practice guideline's AAS clinical decision aid is a highly sensitive tool that uses readily available clinical information. It has the potential to improve diagnosis of AAS in the emergency department.

Thoracic and abdominal aortic alterations in dogs affected with systemic hypertension

Aortic remodeling is the consequence of untreated systemic hypertension along with aortic dilatation as a marker for target organ damage in human literature. Therefore, the present study was planned to detect the changes in aorta at the level of aortic root via echocardiography, thoracic descending aorta via radiography and abdominal aorta via ultrasonography in healthy (n = 46), diseased normotensive (n = 20) and systemically hypertensive dogs (n = 60). The aortic root dimensions were measured at the level of aortic annulus, sinus of valsalva, sino-tubular junction and proximal ascending aorta via left ventricular outflow tract view of echocardiography. The thoracic descending aorta was subjectively assessed for any disparity in size and shape of aorta via lateral and dorso-ventral view of chest radiography. The abdominal aorta was assessed via left and right paralumbar window for calculating the aortic elasticity along with aortic and caudal venacaval dimensions to calculate the aortic-caval ratio. The aortic root measurements were dilated (p < 0.001) in systemically hypertensive dogs with a positive correlation (p < 0.001) with systolic blood pressure (BP). Thoracic descending aorta was also (p < 0.05) altered in the size and shape (undulation) of systemically hypertensive dogs. Abdominal aorta was markedly stiffened with reduced elasticity (p < 0.05) along with dilatation (p < 0.01) in hypertensive dogs. Also, there was a positive correlation (p < 0.001) of aortic diameters and aortic-caval ratio and negative correlation (p < 0.001) of aortic elasticity with systolic BP. Therefore, it was concluded that aorta could be considered as an important target organ damage of systemic hypertension in dogs.

Epidemiology, mortality and miss rate of acute aortic syndrome in Ontario, Canada: a population-based study

INTRODUCTION

Acute aortic syndrome (AAS) is a life-threatening emergency. It describes three distinct diagnoses: acute aortic dissection, acute intramural hematoma and penetrating atherosclerotic ulcer. There are currently no accurate estimates for incidence, mortality or misdiagnosis. Our objectives were to determine the incidence, mortality and miss rate of acute aortic syndrome in the emergency department (ED).

METHODS

A population-based retrospective cohort study of anonymously linked data for residents of Ontario, Canada, was carried out. Incident cases of acute aortic syndrome were identified between 2003 and 2018 using a validated algorithm based on ICD-10 codes and death. Incidence (number of cases/population of Ontario), mortality, and miss rate were calculated. Miss rate was defined as when a patient was seen in the ED within 14 days prior to an acute aortic syndrome diagnosis with a presenting complaint consistent with acute aortic syndrome.

RESULTS

There were 1299 cases of acute aortic syndrome over the study period [age mean (SD) 68.03 ± 14.70; female (n = 500, 38.5%); rural areas (n = 111, 8.6%)]. The overall annual incidence for acute aortic syndrome was 0.61 per 100,000. One year mortality decreased from 47.4 to 29.1%. ED mortality was 14.9%. In the 14 days prior to diagnosis 12.5% of patients were seen in the ED with a presentation consistent with acute aortic syndrome.

CONCLUSIONS

Annual incidence of acute aortic syndrome was found to be lower than other population-based studies. Also, the burden of mortality is seen in the ED. Education initiatives should focus on the identification of acute aortic syndrome in the ED to address mortality and miss rate.

Stenting in Brain Hemodynamic Injury of Carotid Origin Caused by Type A Aortic Dissection: Local Experience and Systematic Literature Review

In this study, we report our local experience of type A aortic dissections in patients with cerebral malperfusion treated with carotid stenting before or after aortic surgery, and present a systematic literature review on these patients treated either with carotid stenting (CS) before or after aortic surgery (AS) or with aortic and carotid surgery alone (ACS). We report on patients treated in our center with carotid stenting for brain hemodynamic injury of carotid origin caused by type A dissection since 2018, and a systematic review was conducted in PubMed for articles published from 1990 to 2021. Out of 5307 articles, 19 articles could be included with a total of 80 patients analyzed: 9 from our center, 29 patients from case reports, and 51 patients from two retrospective cohorts. In total, 8 patients were treated by stenting first, 72 by surgery first, and 7 by stenting after surgery. The mean age; initial NIHSS score; time from symptom onset to treatment; post-treatment clinical improvement; post-treatment clinical worsening; mortality rate; follow-up duration; and follow-up mRS were, respectively, for each group (local cohort, CS before AS, ACS, CS after AS): 71.2 ± 5.3 yo, 65.5 ± 11.0 yo; 65.3 ± 13.1 yo, 68.7 ± 5.8 yo; 4 ± 8.4, 11.3 ± 8.5, 14.3 ± 8.0, 0; 11.8 ± 14.3 h, 21 ± 39.3 h, 13.6 ± 17.8 h, 13 ± 17.2 h; 56%, 71%, 86%, 57%; 11%, 28%, 0%, 14%; 25%, 12.3%, 14%, 33%; 5.25 ± 2.9 months, 54 months, 6.8 ± 3.8 months, 14 ± 14.4 months; 1 ± 1; 0.25 ± 0.5, 1.3 ± 0.8, 0.68 ± 0.6. Preoperative carotid stenting for hemodynamic cerebral malperfusion by true lumen compression appears to be feasible, and could be effective and safe, although there is still a lack of evidence due to the absence of comparative statistical analysis. The literature, albeit growing, is still limited, and prospective comparative studies are needed.

Early and Late Mortality Predictors in Patients with Acute Aortic Dissection Type B

BACKGROUND/AIM

Despite technological advances in diagnosis and treatment, in-hospital mortality with acute aortic dissection type B is still about 11%. The purpose of this study was to assess the risk factors for early and long-term adverse outcomes in patients with acute aortic dissection type B treated medically or with conventional open surgery.

METHODS

The present study included 104 consecutive patients with acute aortic dissection type B treated in our Center from January 1st, 1998 to January 1st, 2007. Patient demographic and clinical characteristics as well as in-hospital complications were reviewed. Univariate and multivariate testing was performed to identify the predictors of in-hospital (30-day) and late (within 9 years) mortality.

RESULTS

92 (88.5%) patients were treated medically, while 12 (11.5%) patients with complicated acute aortic dissection type B were treated by open surgical repair. In-hospital complications occurred in 35.7% patients, the most often being acute renal failure (28%), hypotension/shock (24%), mesenteric ischemia (12%), and limb ischemia (8%). The in-hospital mortality rate was 15.7% and the 9-year mortality rate was 51.9%. Independent predictors of early mortality in patients with acute aortic dissection type B were uncontrolled hypertension (HR-20.69) and a dissecting aorta diameter >4.75 cm (HR-6.30). Independent predictors of late mortality were relapsing pain (HR-7.93), uncontrolled hypertension (HR-7.25), and a pathologic difference in arterial blood pressure (>20 mmHg) (HR-5.33).

CONCLUSION

Knowledge of key risk factors may help with a better choice of treatment and mortality reduction in acute aortic dissection type B patients.

Atypical Presentation of Aortic Dissection in a Young Female and the Utility of Point-of-Care Ultrasound in Identifying Aortic Dissection in the Emergency Department

In the absence of prompt diagnosis and treatment, aortic dissection is an extremely dangerous and often fatal medical condition, of which acute coronary syndrome, stroke, limb ischemia, pulmonary embolism, and acute mesenteric ischemia are all possible manifestations. Neurological manifestations of aortic dissection are often missed at presentation. We report a case of a 23-year-old female without any prior characteristics of connective tissue disorder presenting to the emergency department with headache and right upper limb weakness and the utility of bedside point-of-care ultrasound (POCUS) for diagnosing aortic dissection.

An observational thoracic radiographic study of aortic remodeling in dogs with confirmed systemic hypertension

Sustained systemic hypertension (SH) has been shown to cause target organ damage to various tissues in dogs and cats, including the aorta. Aortic dilatation occurs most commonly secondary to SH in people and develops prior to an aortic aneurysm. Our hypothesis was that blinded reviewers could be trained to recognize variable alterations of aortic shape and size on thoracic radiographs of canine patients with SH. A retrospective, observational, cross-sectional study was performed with three blinded reviewers evaluating thoracic radiographic images of 21 dogs with normal blood pressure compared to 145 dogs with system hypertension. Lateral radiographs showed variable aortic undulation and disproportionate enlargement of a portion of the aorta between the ascending and proximal descending aorta compared to the descending aorta just cranial to the diaphragm. On orthogonal projections, the aortic arch to proximal descending aorta bowed laterally similar to changes reported in people with the formation of an aortic "knob." After completing a training module, reviewers of the thoracic images had a 74% agreement with Fleiss' Kappa of 0.50 indicating moderate agreement recognizing SH changes to the thoracic aorta. The more experienced blinded reviewers had accuracies of 85% and 80% for identifying systemic hypertension, slightly better than the less experienced reviewer at 76%. The ratio of thoracic cavity width to aortic knob width was significantly different between the groups (median ratio 3.4 SH vs 4.1 normal). Evidence of target organ damage (TOD) to the thoracic aorta may prompt earlier recognition and treatment for systemic hypertension.

Acute Aortic Syndrome Revisited: JACC State-of-the-Art Review

The purpose of this paper is to describe all available evidence on the distinctive features of a group of 4 life-threatening acute aortic pathologies gathered under the name of acute aortic syndrome (AAS). The epidemiology, diagnostic strategy, and management of these patients has been updated. The authors propose a new and simple diagnostic algorithm to support clinical decision making in cases of suspected AAS, thereby minimizing diagnostic delays, misdiagnoses, and unnecessary advanced imaging. AAS-related entities are reviewed, and a guideline to avoid imaging misinterpretation is provided. Centralization of patients with AAS in high-volume centers with high-volume surgeons is key to improving clinical outcomes. Thus, the role of multidisciplinary teams, an "aorta code" (streamlined emergent care pathway), and aortic centers in the management of these patients is boosted. A tailored patient treatment approach for each of these acute aortic entities is needed, and as such has been summarized. Finally, a set of prevention measures against AAS is discussed.

Novel Blood Biomarkers for a Diagnostic Workup of Acute Aortic Dissection

Acute aortic dissection (AAD) is a rare condition, but together with acute myocardial infarction (AMI) and pulmonary embolism (PE) it belongs to the most relevant and life-threatening causes of acute chest pain. Until now, there has been no specific blood test in the diagnostic workup of AAD. To identify clinically relevant biomarkers for AAD, we applied Proseek^® Multiplex assays to plasma samples from patients with AAD, AMI, PE, thoracic aortic aneurysm (TAA), and non-cardiovascular chest pain (nonCVD). Subsequently, we validated top hits using conventional immunoassays and examined their expression in the aortic tissue. Interleukin 10 (IL-10) alone showed the best performance with a sensitivity of 55% and a specificity of 98% for AAD diagnosis. The combination of D-dimers, high-sensitive troponin T (hs-TnT), interleukin 6 (IL-6), and plasminogen activator inhibitor 1 (PAI1) correctly classified 75% of AAD cases, delivering a sensitivity of 83% and specificity of 95% for its diagnosis. Moreover, this model provided the correct classification of 77% of all analyzed cases. Our data suggest that IL-10 shows potential to be a rule-in biomarker for AAD. Moreover, the addition of PAI1 and IL-6 to hs-TnT and D-dimers may improve the discrimination of suspected AAD, AMI, and PE in patients presenting with acute chest pain.

Implementation of an aortic dissection CT protocol with clinical decision support aimed at decreasing radiation exposure by reducing routine abdominopelvic imaging

Patients suspected of having an acute aortic syndrome in the ED typically undergo CT of the chest/abdomen/pelvis. However, the overwhelming majority of these exams are negative. With the help of clinical decision support, we implemented a new radiologist monitored 'aortic dissection screening protocol' that forgoes routine abdominopelvic imaging in order to reduce radiation dose without compromising diagnostic accuracy. The purpose of the present study is to assess the performance of this protocol. A retrospective analysis was performed to study the effect of the dissection screening protocol on the diagnostic yield, radiation and contrast dose on a total of 835 ED patients who underwent CT scans for suspected aortic dissection over a 48-week study period immediately before and after implementation of the protocol. 3.4% (28/835) of examinations were positive for an acute aortic syndrome over the 48-week study period with no difference in positivity before and after implementation of the 'aortic dissection screening' protocol, 3.0% vs. 3.7%, respectively (p = 0.57). There was a 14.6% reduction in median radiation dose and a 16% decrease in contrast volume utilization for the total ED population who underwent CT for aortic dissection using any protocol in the period after implementation of the 'aortic dissection screening' protocol. Aortic dissection CT in the ED is negative in the overwhelming majority of cases. A monitored 'aortic dissection screening' protocol that initially images the chest only significantly reduced contrast and radiation dose without reducing diagnostic accuracy for ED patients who underwent CT for aortic dissection.

Characterizing Agreement in the Level of Interarm Blood Pressure Readings of Adults in the Emergency Department (CALIBRATE Study)

Background: Increased interarm systolic blood pressure difference (IASBPD) is one of the major predictors of cardiovascular disease. An IASBPD of >10 mmHg is of clinical significance. However, studies have reported a high number of patients visiting the emergency department (ED) with high IASBPD and varying correlation of IASBPD to age, ethnic background, and comorbidities such as hypertension and diabetes. Objective: The CALIBRATE study aimed to measure the IABPDs in the multiethnic patient population presenting to the ED in Qatar and to assess the distribution of IASBPD in this population. Methods: In a sitting position, two consecutive blood pressure (BP) measurements were recorded from the right and left arms for each participant using a calibrated automated machine and appropriate cuff sizes. The data were recorded using predefined data fields, including patient demographics, past medical, and social and family history. The continuous variables were reported as mean or median based on the distribution of data. The data were analyzed using Stata MP 14.0. Results: A total of 1800 patients, with a mean age of 34 (10) years, were prospectively recruited from the ED. The median absolute systolic BP difference (ΔSBP) between the right and left arms was 6 (3-10) mmHg, and it was the same for the first (ΔSBP1) and the second readings (ΔSBP2). The absolute average of ΔSBP1 and ΔSBP2 was 7 (4-10) mmHg. The difference in systolic BP difference (SBP) of < 20 mmHg for interarm blood pressure was seen in the 95th percentile of the population. No meaningful association could be detected between the IABPD and the study variables such as age, demographics, regions of interest, and risk factors. Conclusion: In population presenting to the ED, the IASBPD of at least 20 mmHg reached at the 95th percentile, validating the known significant difference. The utility of SBP difference can be improved further by taking the average of two individual readings.

High-Risk Chief Complaints I: Chest Pain-The Big Three (an Update)

Nontraumatic chest pain is a frequent concern of emergency department patients, with causes that range from benign to immediately life threatening. Identifying those patients who require immediate/urgent intervention remains challenging and is a high-risk area for emergency medicine physicians where incorrect or delayed diagnosis may lead to significant morbidity and mortality. This article focuses on the 3 most prevalent diagnoses associated with adverse outcomes in patients presenting with nontraumatic chest pain, acute coronary syndrome, thoracic aortic dissection, and pulmonary embolism. Important aspects of clinical evaluation, diagnostic testing, treatment, and disposition and other less common causes of lethal chest pain are also discussed.

[Acute post-trauma dissection of the descending thoracic aorta]

BACKGROUND

Traumatic injury to the descending thoracic aorta other than the isthmus is rare, and little known. Acute post-trauma rupture may occur in a context of multiple or rarely unique localizations.

CASE REPORT

We report the case of a young man who was the victim of multiple injuries with an isolated rupture of the descending thoracic aorta. Early diagnosis and adapted endovascular treatment led to favorable outcome.

CONCLUSION

In 90% of cases, acute post-trauma rupture of the aorta in a single localization involve the isthmus. Rupture of the descending aorta is more exceptional but must not be missed. The pathophysiological mechanism and appropriate management are discussed in light of a review of the literature.

Detection of Type B Aortic Dissection in the Emergency Department with Point-of-Care Ultrasound

Aortic dissection (AD) is a rare, time-sensitive, and potentially fatal condition that can present with subtle signs requiring timely diagnosis and intervention. Although definitive diagnosis is most accurately made through computed tomography angiography, this can be a time-consuming study and the patient may be unstable, thus preventing the study’s completion. Chest radiography (CXR) signs of AD are classically taught yet have poor diagnostic reliability. Point-of-care ultrasound (POCUS) is increasingly used by emergency physicians for the rapid diagnosis of emergent conditions, with multiple case reports illustrating the sonographic signs of AD. We present a case of Stanford type B AD diagnosed by POCUS in the emergency department in a patient with vague symptoms, normal CXR, and without aorta dilation. A subsequent review of CXR versus sonographic signs of AD is described.

Aortic Dissection with Subsequent Hemorrhagic Tamponade Diagnosed with Point-of-care Ultrasound in a Patient Presenting with STEMI

A 58-year-old male with no past medical history presented to the emergency department with sudden onset left lower extremity weakness and central chest pain with radiation to his back. Electrocardiogram revealed an acute inferior and posterior ST-segment elevation myocardial infarction (STEMI). Point-of-care ultrasound (POCUS) demonstrated right ventricular akinesis consistent with infarction, and an intimal defect consistent with an aortic dissection. We determined that cardiothoracic surgery was indicated rather than left-heart catheterization and anticoagulation. Using POCUS we were able to immediately diagnose a dissection of the aortic arch and considerably alter treatment in a patient presenting with STEMI.

Usefulness of Fibrinogen/Fibrin Degradation Products Value in Differential Diagnosis Between Acute Ischemic Stroke and Acute Aortic Dissection

A post-marketing surveillance study reported fatalities following tissue plasminogen activator administration in acute aortic dissection (AAD) with the symptoms of acute ischemic stroke (AIS) patients. Therefore, it is important to discriminate AAD from AIS. The present study aimed to investigate whether fibrinogen/fibrin degradation products (FDP) value can be useful in differential diagnosis between AAD and AIS. The study group comprised 20 AAD patients (10 men and 10 women; age 63.9 ± 13.6 years) and 159 AIS patients (91 men and 68 women; age 74.2 ± 10.6 years) who were transported to our hospital from 2007 to 2012. The AAD cases were further divided into patent-type AAD and thrombosed-type AAD. FDP values were significantly higher in the AAD group than in the AIS group (18.15 [5.2 - 249.9] μg/ml vs. 2.3 [1.5 - 4.45] μg/ml ; P < 0.001). In AAD groups, FDP values were significantly higher in the patent-type AAD group (n = 9) than in the thrombosed type AAD group (n = 11) (293.2 μg/ml [63.1 - 419.6 μg/ml ] vs. 5.6 μg/ml [3.8 - 7.9 μg/ml ]. FDP values were significantly higher in patients with AAD than in those with AIS, especially those with patent-type AAD compared with AIS patients. High FDP values may be a useful marker for differential diagnosis between patent-type AAD and AIS.

Point-of-care Ultrasound Diagnosis of an Atypical Acute Aortic Dissection

Aortic dissections have a vast array of clinical presentations that rarely follow traditional teachings. Dissections are rapidly fatal conditions requiring immediate diagnosis and treatment to reduce morbidity and mortality. We present a case of an acute aortic dissection presenting as abrupt onset, atraumatic leg pain with absent distal extremity pulses. The prompt use of point-of-care ultrasound detected an intimal flap within the abdominal aorta allowing immediate surgical consultation and intervention.

Thoracic Aortic Syndromes

Aortic dissection (AD) is a lethal, treatable disruption of the aortic vessel wall. It often presents without classic features, mimicking symptoms of other conditions, and diagnosis is often delayed. Established high-risk markers of AD should be sought and indicate advanced aortic imaging with CT, MRI, or TEE. Treatment is immediate surgical evaluation, aggressive symptom relief, and reduction of the force of blood against the aortic wall by control of heart rate, followed by blood pressure.

Prospective study of a non-restrictive decision rule for acute aortic syndrome

OBJECTIVES

To determine the impact of a non-restrictive clinical decision rule on CT utilization for Emergency Department patients suspected of having an acute aortic syndrome (AAS).

METHODS

We prospectively assessed the performance of a previously described, collaboratively designed, non-restrictive clinical decision rule for AAS. Emergency Department patients with suspected AAS were stratified into low and high-risk groups based on decision rule results, from July 2013-August 2014. Patients with acute trauma, prior AAS or aortic surgery were excluded. CT dose reduction protocols were concurrently implemented as a quality improvement measure. Bivariate analysis was performed to compare the prospective cohort with the historical derivation cohort for CT utilization rates, results of CT, AAS incidence and radiation exposure. The performance of the clinical decision rule was evaluated.

RESULTS

Compared with the historic cohort, the study cohort demonstrated a lower CT utilization rate [0.344% (427/124,093) versus 0.477% (1465/306,961), (p<0.001)], a trend toward higher CT diagnostic yield [4.4% (19/427) versus 2.7% (40/1465), (p=0.08)]. AAS incidence was similar [0.015% (19/124,093) versus 0.013% (40/306,961), (p=0.57)]. The mean effective radiation dose was markedly lower [12±5.5mSv versus 43±20mSv, (p<0.0001)]. The clinical decision rule correctly stratified only 56% (10/18) of patients with AAS as high-risk.

CONCLUSIONS

A non-restrictive, collaboratively designed, clinical decision rule for Emergency Department patients with suspected AAS performed poorly in risk-stratifying patients for AAS. However, its implementation was associated with a significant and safe decrease in CT utilization.

Chest radiography in acute aortic syndrome: pearls and pitfalls

Acute aortic syndrome is a group of life-threatening diseases of the thoracic aorta that usually present to the emergency department. It includes aortic dissection, aortic intramural hematoma, and penetrating aortic ulcer. Rare aortic pathologies of aorto-esophageal fistula and mycotic aneurysm may also be included in this list. All these conditions require urgent treatment with complex clinical care and management. Most patients who present with chest pain are evaluated with a chest radiograph in the emergency department. It is important that maximum diagnostic information is extracted from the chest radiograph as certain signs on the chest radiograph are extremely useful in pointing towards the diagnosis of acute aortic syndrome.

Outcomes before and after the Implementation of a Critical Pathway for Patients with Acute Aortic Disease

PURPOSE

Acute aortic diseases, such as aortic dissection and aortic aneurysm, can be life-threatening vascular conditions. In this study, we compared outcomes before and after the implementation of a critical pathway (CP) for patients with acute aortic disease at the emergency department (ED).

MATERIALS AND METHODS

This was a retrospective observational cohort study. The CP was composed of two phases: PRE-AORTA for early diagnosis and AORTA for prompt treatment. We compared patients who were diagnosed with acute aortic disease between pre-period (January 2010 to December 2011) and post-period (July 2012 to June 2014).

RESULTS

Ninety-four and 104 patients were diagnosed with acute aortic disease in the pre- and post-periods, respectively. After the implementation of the CP, 38.7% of acute aortic disease cases were diagnosed via PRE-AORTA. The door-to-CT time was reduced more in PRE-AORTA-activated patients [71.0 (61.0, 115.0) min vs. 113.0 (56.0, 170.5) min; p=0.026]. During the post-period, more patients received emergency intervention than during the pre-period (22.3% vs. 36.5%; p=0.029). Time until emergency intervention was reduced in patients, who visited the ED directly, from 378.0 (302.0, 489.0) min in the pre-period to 200.0 (170.0, 299.0) min in the post-period (p=0.001). The number of patients who died in the ED declined from 11 to 4 from the pre-period to the post-period. Hospital mortality decreased from 26.6% to 14.4% in the post-period (p=0.033).

CONCLUSION

After the implementation of a CP for patients with acute aortic disease, more patients received emergency intervention within a shorter time, resulting in improved hospital mortality.

A case of ascending aortic dissection mimicking acute myocardial infarction and complicated with pericardial tamponade

Acute aortic dissection (AD) is the most common life-threatening disorder affecting the aorta with an incidence that ranges between 5 to 30 cases per million people per year. The symptoms of aortic dissection may be variable and can mimic other more common conditions such as myocardial ischemia. We report a case of a 60-year-old male who presented with inferior wall ST-elevation myocardial infarction (MI). Emergent coronary angiography revealed an ascending aortic dissection with normal coronary arteries. In addition, his aortic dissection was complicated with pericardial tamponade. The patient was managed with an immediate surgical repair, after that he had an uncomplicated postoperative course and was discharged in a stable condition. This case report illustrates the importance of having a high index of suspicion for AD in cases of chest pain. If AD is suspected in a patient with acute coronary syndrome (ACS), confirming the diagnosis with the appropriate imaging studies should be done as quickly as possible, as misdiagnosis with ACS may lead to the inappropriate administration of thrombolytic or anticoagulant agents resulting in catastrophic outcomes.

Aortic Dissection and Sudden Unexpected Deaths: A Retrospective Study of 31 Forensic Autopsy Cases

Acute aortic dissection (AAD) is the most common cause of sudden unexpected death related to aortic diseases. A retrospective study of 31 sudden unexpected deaths caused by AAD was conducted at Xi'an Jiaotong University Forensic Center from 2001 to 2012. We summarized the forensic characteristics of AAD and assessed the clinically diagnostic accuracy of AAD. The characteristics of sudden unexpected death due to AAD were male predominant (male: female=6.7:1), relatively young with the mean age of 44, and predominance of type A dissection (77.4%). Cardiac tamponade was the most frequent cause of sudden death (87.1%). Of the 31 cases, 26 (83.9%) patients were not recognized clinically and were misdiagnosed with acute myocardial infarction, coronary artery disease, cholecystitis, acute gastroenteritis, renal/urinary lithiasis, or acute pancreatitis. In summary, AAD can be difficult to recognize, diagnosis is therefore sometimes delayed or missed. The medicolegal death investigation can help physicians have a better understanding of AAD.

What Lies behind the Ischemic Stroke: Aortic Dissection?

Introduction. Some cases with aortic dissection (AD) could present with various complaints other than pain, especially neurological and cardiovascular manifestations. AD involving the carotid arteries could be associated with many clinical presentations, ranging from stroke to nonspecific headache. Case Report. A 71-year-old woman was admitted to emergency department with vertigo which started within the previous one hour and progressed with deterioration of consciousness following speech disorder. On arrival, she was disoriented and uncooperative. Diffusion magnetic resonance imaging (MRI) of brain was consistent with acute ischemia in the cerebral hemisphere. Fibrinolytic treatment has been planned since symptoms started within two hours. Echocardiography has shown the dilatation of ascending aorta with a suspicion of flap. Computed tomography (CT) angiography has been applied and intimal flap has been detected which was consistent with aortic dissection, intramural hematoma of which was reaching from aortic arch to bilateral common carotid artery. Thereafter, treatment strategy has completely changed and surgical invention has been done. Conclusion. In patients who are admitted to the emergency department with the loss of consciousness and stroke, inadequacy of anamnesis and carotid artery involvement of aortic dissection should be kept in mind.

Diagnostic performance of emergency transthoracic focus cardiac ultrasound in suspected acute type A aortic dissection

Type A aortic dissection (AD) is a deadly disease. Rapid identification of patients requiring immediate advanced aortic imaging or transfer to specialized centers is needed to improve outcomes. We evaluated the diagnostic performance of transthoracic focus cardiac ultrasound (FOCUS) performed by emergency physicians, alone and in combination with the aortic dissection detection (ADD) risk score in suspected type A AD. This was a prospective study performed on patients with suspected type A AD. FOCUS evaluated the presence of intimal flap/intramural hematoma (direct signs of AD), ascending aorta dilatation, aortic valve insufficiency or pericardial effusion/tamponade (indirect signs of AD). The ADD risk score of each patient was calculated according to guidelines. The final diagnosis was established after review of complete clinical data. 50 (18%) patients of 281 had a final diagnosis of type A AD. Detection of any FOCUS sign (direct or indirect) of AD had a sensitivity of 88% (95% CI 76-95%) for the diagnosis of type A AD. Presence of ADD risk score > 0 or detection of any FOCUS sign increased diagnostic sensitivity to 96% (95% CI 86-99%). Detection of direct FOCUS signs had a specificity of 94% (95% CI 90-97%), while combination of ADD risk score > 1 with detection of direct FOCUS signs had a specificity of 98% (95% CI 96-99%). FOCUS demonstrated acceptable accuracy as a triage tool to rapidly identify patients with suspected type A AD needing advanced aortic imaging or transfer, but it cannot be used as a stand-alone test even if combined with ADD risk score classification.

Combined use of aortic dissection detection risk score and D-dimer in the diagnostic workup of suspected acute aortic dissection

BACKGROUND

Acute aortic dissection (AD) represents a diagnostic conundrum. Validated algorithms are particularly needed to identify patients where AD could be ruled out without aortic imaging. We evaluated the diagnostic accuracy of a strategy combining the aortic dissection detection (ADD) risk score with D-dimer, a sensitive biomarker of AD.

METHODS

Patients from two clinical centers with suspected AD were prospectively enrolled in a registry, from January 2008 to March 2013. The ADD risk score was calculated by retrospective blinded chart review. For D-dimer, a cutoff of 500 ng/ml was applied.

RESULTS

AD was diagnosed in 233 of 1035 (22.5%) patients. The ADD risk score was 0 in 322 (31.1%), 1 in 508 (49.1%) and >1 in 205 (19.8%) patients. The sensitivity and the failure rate of D-dimer were 100% and 0% in patients with ADD score 0, versus 97.5% (95% CI 91.4-99.6%) and 4.2% (95% CI 0.7-12.5%) in patients with ADD risk score >1. In patients with ADD risk score ≤ 1, the sensitivity and the failure rate of D-dimer were 98.7% (95% CI 95.3-99.8%) and 0.8% (95% CI 0.1-2.6%). The diagnostic efficiency of D-dimer in patients with ADD risk score 0 and ≤ 1 was 8.9% (95% CI 7.2-10.7%) and 23.6% (95% CI 21.1-26.2%) respectively.

CONCLUSIONS

In a large cohort of patients with suspected AD, the presence of ADD risk score 0 or ≤ 1 combined with a negative D-dimer accurately and efficiently ruled out AD.

A fatal outcome of thoracic aortic aneurysm in a male patient with bicuspid aortic valve

Thoracic aortic aneurysm is often an asymptomatic but potentially lethal disease if its most catastrophic complication – aortic dissection – occurs. Thoracic aortic dissection is associated with a high mortality rate despite ongoing improvement in its management. We report a fatal outcome of thoracic aortic aneurysm in a male patient with bicuspid aortic valve. The patient was qualified for elective surgery of the ascending aorta and aortic valve at the age of 39 but he did not agree to undergo the proposed procedure. Three years later, he experienced acute aortic dissection and died despite a prompt diagnosis and complex management.

Preliminary development of a clinical decision rule for acute aortic syndromes

OBJECTIVE

Patients with suspected acute aortic syndromes (AAS) often undergo computed tomography (CT) with negative results. We sought clinical and diagnostic criteria to identify low-risk patients, an initial step in developing a clinical decision rule.

METHODS

We retrospectively identified all adults presenting to our emergency department (ED) from January 1, 2006, to August 1, 2010, who underwent CT angiography for suspected AAS without prior trauma or AAS. A total of 1465 patients met inclusion criteria; a retrospective case-controlled review (ratio 1:4) was conducted. Cases were diagnosed with aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer, or ruptured aneurysm.

RESULTS

Of the patients who underwent CT, 2.7% (40/1465) had an AAS; 2 additional cases were diagnosed after admission (ED miss rate, 5% [2/42]). Patients with AAS were significantly older than controls (66 vs 59 years; P = .008). Risk factors included abnormal chest radiograph (sensitivity, 79% [26/33]; specificity, 82% [113/137]) and acute chest pain (sensitivity, 83% [29/35]; specificity, 71% [111/157]). None of the 19 patients with resolved pain upon ED presentation had AAS. These data support a 2-step rule: first screen for ongoing pain; if present, screen for acute chest pain or an abnormal chest radiograph. This approach achieves a 54% (84/155) reduction in CT usage with a sensitivity for AAS of 96% (95% confidence interval, 89%-100%), negative predictive value of 99.8% (99.4%-100%), and a false-negative rate of 1.7% (1/84).

CONCLUSIONS

Our results demonstrate a need to safely identify patients at low risk for AAS who can forgo CT. We developed a preliminary 2-step clinical decision rule, which requires validation.

Screening, evaluation, and early management of acute aortic dissection in the ED

Acute aortic dissection (AAD) is a rare and lethal disease with presenting signs and symptoms that can often be seen with other high risk conditions; diagnosis is therefore often delayed or missed. Pain is present in up to 90% of cases and is typically severe at onset. Many patients present with acute on chronic hypertension, but hypotension is an ominous sign, often reflecting hemorrhage or cardiac tamponade. The chest x-ray can be normal in 10-20% of patients with AAD, and though transthoracic echocardiography is useful if suggestive findings are seen, and should be used to identify pericardial effusion, TTE cannot be used to exclude AAD. Transesophageal echocardiography, however, reliably confirms or excludes the diagnosis, where such equipment and expertise is available. CT scan with IV contrast is the most common imaging modality used to diagnose and classify AAD, and MRI can be used in patients in whom the use of CT or IV contrast is undesirable. Recent specialty guidelines have helped define high-risk features and a diagnostic pathway that can be used the emergency department setting. Initial management of diagnosed or highly suspected acute aortic dissection focuses on pain control, heart rate and then blood pressure management, and immediate surgical consultation.

Acute aortic dissection in the ED: risk factors and predictors for missed diagnosis

OBJECTIVE

This study aims to explore the risk factors and predictors involved in the missed diagnosis of acute aortic dissection (AAD) among patients in the emergency medicine department (EMD).

METHODS

This is a single-center retrospective chart review conducted over a 10-year period (January 1998 to December 2008). Records with a diagnosis of "dissection of aorta" (International Classification of Diseases, Ninth Revision code 441.0) from the hospital discharge database and hospital death register were selected. Acute aortic dissection was defined as missed if diagnostic imaging to diagnose AAD or cardiothoracic surgeon consult was not elicited while in the EMD. We compared the history, clinical findings, and investigations between patients who had the diagnosis of AAD missed in the EMD and those who did not.

RESULTS

A total of 68 patients were included in the analysis during the study period, of which 38.2% had a missed diagnosis. There was 63.2% of type A AAD by Stanford classification. Neither age, sex, nor a history of hypertension were significant risk factors for missed diagnosis of AAD. The likelihood of missed diagnosis was significantly higher in the absence of a pulse deficit (odds ratio, 35.76; 95% confidence interval, 3.70-345.34) and absence of widened mediastinum on chest radiography (odds ratio, 33.16; 95% confidence interval, 5.74-191.49).

CONCLUSION

Well-known risk factors for AAD such as age, male sex, and hypertension were not risk factors for missed diagnosis for AAD presenting in the EMD. The absence of pulse deficit or widened mediastinum does not exclude the diagnosis of AAD.

A successfully thrombolysed acute inferior myocardial infarction due to type A aortic dissection with lethal consequences: the importance of early cardiac echocardiography

Thrombolysis, a standard therapy for ST elevation myocardial infarction (STEMI) in non-PCI-capable hospitals, may be catastrophic for patients with aortic dissection leading to further expansion, rupture and uncontrolled bleeding. Stanford type A aortic dissection, rarely may mimic myocardial infarction. We report a case of a patient with an inferior STEMI thrombolysed with tenecteplase and followed by clinical and electrocardiographic evidence of successful reperfusion, which was found later to be a lethal acute aortic dissection. Prognostic implications of early diagnosis applying transthoracic echocardiography (TTE) are described.

[Acute traumatic thoracic aortic rupture in double localisation]

PURPOSE

Traumatic thoracic aortic rupture are commonly localised in one site essentially in the aortic isthmus but multiple localisation are not uncommon. The authors reported the case of a young man who had a double localisation of RTA after a violent car accident.

CASE REPORT

A 23-year-old man had a violent car crush involving sudden deceleration. He had multiple injuries essentially: a traumatic thoracic injury with acute posttraumatic aortic rupture in double localization, in the isthmus and in the descending thoracic aorta. He underwent thoracic endovascular aortic repair (TEVAR) with the use of stent graft three weeks after his car accident. The endovascular treatment was successful and no case of perigraft leakage has been detected during a meaning follow-up of five months.

CONCLUSION

The systematic analysis of the whole thoracic aortic vessel is crucial to not misdiagnose eventual multiple aortic rupture.

Sensitivity of the aortic dissection detection risk score, a novel guideline-based tool for identification of acute aortic dissection at initial presentation: results from the international registry of acute aortic dissection

BACKGROUND

In 2010, the American Heart Association and American College of Cardiology released guidelines for the diagnosis and management of patients with thoracic aortic disease, which identified high-risk clinical features to assist in the early detection of acute aortic dissection. The sensitivity of these risk markers has not been validated.

METHODS AND RESULTS

We examined patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2009. The number of patients with confirmed acute aortic dissection who presented with 1 or more of 12 proposed clinical risk markers was determined. An aortic dissection detection (ADD) risk score of 0 to 3 was calculated on the basis of the number of risk categories (high-risk predisposing conditions, high-risk pain features, high-risk examination features) in which patients met criteria. The ADD risk score was tested for sensitivity. Of 2538 patients with acute aortic dissection, 2430 (95.7%) were identified by 1 or more of 12 proposed clinical risk markers. With the use of the ADD risk score, 108 patients (4.3%) were identified as low risk (ADD score 0), 927 patients (36.5%) were intermediate risk (ADD score 1), and 1503 patients (59.2%) were high risk (ADD score 2 or 3). Among 108 patients with no clinical risk markers present (ADD score 0), 72 had chest x-rays recorded, of which 35 (48.6%) demonstrated a widened mediastinum.

CONCLUSIONS

The clinical risk markers proposed in the 2010 thoracic aortic disease guidelines and their application as part of the ADD risk score comprise a highly sensitive clinical tool for the detection of acute aortic dissection.

Spanish Acute Aortic Syndrome Study (RESA). Better diagnosis is not reflected in reduced mortality

INTRODUCTION AND OBJECTIVES

Because acute aortic syndrome (AAS) is associated with high mortality, early diagnosis and treatment are vital. The aim of the Spanish Acute Aortic Syndrome Study (RESA) was to investigate the effectiveness of current treatment of AAS in a broad range of tertiary care hospitals in Spain.

METHODS

Between January 2005 and December 2007, 24 tertiary care hospitals reported data on 519 patients with AAS (78% male, mean age 61 +/- 13 years, range 20-92 years): 357 had type-A AAS and 162 had type B.

RESULTS

The time delay between symptom onset and diagnosis was <24 hours in 67% of cases and >72 hours in 11%. Some 80% of patients with type-A AAS were treated surgically. The interval between diagnosis and surgery was <24 hours in 90% of cases. In patients with type-B AAS, 34% received invasive treatment: 11% had surgery and 23% underwent endovascular procedures. Mortality during hospitalization in patients with type-A disease was 33% in those treated surgically and 71% in those treated medically. Mortality in patients with type-B disease was 17% with medical treatment, 27% with endovascular treatment and 50% with surgical treatment.

CONCLUSIONS

Despite significant advances in the diagnosis of AAS, in-hospital mortality remains high. The findings of this study are representative of a broad range of unselected patients undergoing treatment for the disease and support the need for continuing improvements in therapeutic approaches to AAS.

High-risk chief complaints I: chest pain--the big three

Chest pain is one of the most frequently seen chief complaints in patients presenting to emergency departments, and is considered to be a "high-risk" chief complaint. The differential diagnosis for chest pain is broad, and potential causes range from the benign to the immediately life-threatening. Although many (if not most) emergency department patients with chest pain do not have an immediately life-threatening condition, correct diagnoses can be difficult to make, incorrect diagnoses may lead to catastrophic therapies, and failure to make a timely diagnosis may contribute to significant morbidity and mortality. Several atraumatic "high-risk" causes of chest pain are discussed in this article, including myocardial infarction and ischemia, thoracic aortic dissection, and pulmonary embolism. Also included are brief discussions of tension pneumothorax, esophageal perforation, and cardiac tamponade.

Fever of unknown origin as a primary presentation of chronic aortic dissection

Fever of unknown origin is rare as a primary presentation of aortic dissection. We describe a 69-year-old female presenting with a sustained fever. A diagnosis of chronic type A aortic dissection was established by computed tomography. Replacements of the ascending aorta and part of the aortic arch were performed. Ten days after the operation, the patient had recurrent pyrexia. A large effusion in the left pleural cavity was found. After puncture aspiration and antibiotic treatment, she recovered. She was doing well at the 5(1/2)-year follow-up.