Major pulmonary embolism: review of a pathophysiologic approach to the golden hour of hemodynamically significant pulmonary embolism

Diagnostic Accuracy of Point-of-Care Ultrasound Performed by Pulmonary Critical Care Physicians for Right Ventricle Assessment in Patients With Acute Pulmonary Embolism

OBJECTIVES

Risk stratification for acute pulmonary embolism using imaging presence of right ventricular dysfunction is essential for triage; however, comprehensive transthoracic echocardiography has limited availability. We assessed the accuracy and timeliness of Pulmonary Critical Care Medicine Fellow's performance of goal-directed echocardiograms and intensivists' interpretations for evaluating right ventricular dysfunction in acute pulmonary embolism.

DESIGN

Prospective observational study and retrospective chart review.

SETTING

Four hundred fifty bed urban teaching hospital.

PATIENTS

Adult in/outpatients diagnosed with acute pulmonary embolism.

INTERVENTIONS

Pulmonary critical care fellows performed and documented their goal-directed echocardiogram as normal or abnormal for right ventricular size and function in patients with acute pulmonary embolism. Gold standard transthoracic echocardiography was performed on schedule unless the goal-directed echocardiogram showed critical findings. Attending intensivists blinded to the clinical scenario reviewed these exams at a later date.

MEASUREMENTS AND MAIN RESULTS

Two hundred eighty-seven consecutive patients were evaluated for acute PE. Pulmonary Critical Care Medicine Fellows performed 154 goal-directed echocardiograms, 110 with complete cardiology-reviewed transthoracic echocardiography within 48 hours for comparison. Pulmonary Critical Care Medicine Fellow's area under the curve for size and function was 0.83 (95% CI, 0.75-0.90) and 0.83 (95% CI, 0.75-0.90), respectively. Intensivists' 1/2 area under the curve for size and function was (1) 0.87 (95% CI, 0.82-0.94), (1) 0.87 (95% CI, 0.80-0.93) and (2) 0.88 (95% CI, 0.82-0.95), (2) 0.88 (95% CI, 0.82-0.95). Median time difference between goal-directed echocardiogram and transthoracic echocardiography was 21 hours 18 minutes.

CONCLUSIONS

This is the first study to evaluate pulmonary critical care fellows' and intensivists' use of goal-directed echocardiography in diagnosing right ventricular dysfunction in acute pulmonary embolism. Pulmonary Critical Care Medicine Fellows and intensivists made a timely and accurate assessment. Screening for right ventricular dysfunction using goal-directed echocardiography can and should be performed by pulmonary critical care physicians in patients with acute pulmonary embolism.

Multiple cardiac arrests induced by pulmonary embolism in a traumatically injured patient: A case report and review of the literature

RATIONALE

Pulmonary embolism-induced cardiac arrest should not be given up arbitrarily, knowing that the etiology of pulmonary embolism is reversible in most cases.

PATIENT CONCERNS

We present a case of continuous resuscitation lasting approximately 4 hours, during which 21 episodes of cardiac arrest occurred in a 46-year-old man who sustained high-level paraplegia after a road traffic accident.

DIAGNOSES

Multiple cardiac arrests induced by pulmonary embolism.

INTERVENTIONS

The patient received cardiopulmonary resuscitation and thrombolytic therapy.

OUTCOMES

The patient was discharged in 2 weeks when his condition turned for the better.

LESSONS

Cardiopulmonary resuscitation of patients with pulmonary embolism-induced cardiac arrest should not be given up arbitrarily, knowing that the etiology of pulmonary embolism is reversible in most cases. Effective external cardiac compression can not only save the patient's life but also attenuate neurological sequelae. Thrombolytic therapy is the key to the final success of resuscitation.

Effectiveness of prognosticating pulmonary embolism using the ESC algorithm and the Bova score

The prognostic value of the European Society of Cardiology (ESC) 2014 algorithm and the Bova score has lacked adequate validation. According to the ESC 2014 guidelines and the Bova score, we retrospectively risk stratified normotensive patients with PE who were enrolled in the PROTECT study. This study used a complicated course (which consisted of death from any cause, haemodynamic collapse, or recurrent PE) as the primary endpoint, and follow-up occurred through 30 days after the PE diagnosis. Of 848 patients, 37 % had a sPESI of 0 and 5 (1.6 %; 95 % confidence interval [CI], 0.5-3.7 %) experienced a complicated course. Of 143 patients with a sPESI of 0 points and negative computed tomographic pulmonary angiography (CTPA) for right ventricle (RV) dysfunction, three (2.1 %; 95 % CI, 0.4-6.0 %) experienced a complicated course. Four hundred seventy-eight (56 %) patients with a sPESI ≥ 1 had echocardiographic evidence of RV dysfunction or elevated troponin level or none, and 48 (10 %, 95 % CI, 7.5-13.1 %) experienced a complicated course. Fifty-seven (6.7 %) patients with a sPESI ≥ 1 had echocardiographic RV dysfunction and elevated troponin level, and 10 (17.5 %; 95 % CI, 8.8-29.9 %) experienced a complicated course, compared to 21.6 % (8 of 37 patients, 21.6 %; 95 % CI, 9.8-38.2 %) in Bova risk class III. In conclusion, the ESC 2014 prognostic algorithm is effective in the risk stratification of normotensive patients with PE. Use of CTPA did not improve the ability for identification of low-risk PE. Bova risk scoring did not significantly improve identification of intermediate-high risk PE.

Jiménez et al. Validation of the ESC 2014 prognostication algorithm

Automated volumetric analysis of four cardiac chambers in pulmonary embolism

Identification of patients with acute pulmonary embolism (PE) who might be at risk of circulatory collapse by using a fast, automated system is highly desired. It was our objective to investigate whether automated cardiac volumetric analysis following computerised tomographic pulmonary angiography (CTPA) is useful to identify increased clot load and adverse prognosis in patients with acute PE. We retrospectively analysed a consecutive series of non-gated CTPA studies of 124 patients with acute PE and 43 controls. Right and left ventricular diameters (RV/LV) were measured on four-chamber view, while each cardiac chamber underwent automatic volumetric measurements. Findings were correlated to the pulmonary arterial obstruction index (PAOI). Outcome was expressed by admission to an intensive care unit (ICU) or mortality within 30 days. There was a significant positive correlation between the PAOI and the volumes of the right side cavities (r=0.25 for the atrium and r=0.49 for the ventricle), and between the right-to-left atrial and ventricular volume ratios (r=0.49 and r=0.57, respectively). Results for the combined outcome of mortality or ICU admission that fell in the upper tertile of the right atrial and right ventricular volumes yielded hazard ratios of 3.9 and 3.3, respectively, compared to those in the lower tertile. RV/LV diameter ratio did not correlate with outcome. In conclusion, adverse outcome and significant pulmonary clot load in patients with acute PE are associated with a volume shift towards right heart cavities, which correlates to prognosis better than the CT-measured RV/LV diameter ratio, suggesting the advantage of using fast fully automatic volumetric analysis to identify patients at risk.

Catheter-Directed Therapy for Pulmonary Embolism: Patient Selection and Technical Considerations

Acute pulmonary embolism (PE) is the third most common cause of death among hospitalized patients. Treatment escalation beyond anticoagulation therapy is necessary in patients with cardiogenic shock and may be of benefit in select normotensive patients with right heart strain. Percutaneous catheter-based techniques (catheter-directed mechanical thrombectomy, clot maceration, and/or pharmacologic thrombolysis) as an alternative or adjunct to systemic thrombolysis can rapidly debulk central clot in patients with shock. Catheter-directed thrombolysis, which uses a low-dose intraclot prolonged thrombolytic infusion, is a promising but insufficiently studied therapy for patients presenting with acute intermediate-risk PE.

Catheter-directed therapy as a treatment for submassive pulmonary embolism: A meta-analysis

AIMS

Catheter-directed therapy (CDT) is included in the guidelines for diagnosing and treating massive pulmonary embolism. However, few studies have evaluated the efficacy of CDT as a treatment for submassive pulmonary embolism (SPE). Therefore, we used evidence-based medicine to evaluate the effectiveness and safety of CDT in treating SPE.

METHODS

Search terms describing CDT in SPE and patients with intermediate pulmonary embolism were entered into the PubMed, Embase and Cochrane Library databases to identify relevant articles without language restrictions published between January 1990 and December 2016. A quality assessment and data extraction were performed by two investigators. The clinical efficacy of and major complications associated with treatment were analysed using a fixed effects model.

KEY FINDINGS

A total of 552 patients in 16 studies were included in this meta-analysis. The clinical success rate in CDT was approximately 100% (95% confidence interval (CI): 99%, 100%), the primary bleeding rate was 0.02% (95% CI: 0%, 0.05%), and mortality during hospitalization was approximately 0% (95% CI: 0%, 0.01%). The mean decrease in pulmonary artery systolic pressure after treatment was -14.9% (95% CI: -19.25%, -10.55%), and the mean post-treatment change in the ratio of the right to the left ventricle (RV/LV) was -0.35% (95% CI: -0.48%, -0.22%).

SIGNIFICANCE

CDT is effective and safe as a treatment for SPE and could be a first-line treatment for SPE under specific conditions.

Saddle vs Nonsaddle Pulmonary Embolism: Clinical Presentation, Hemodynamics, Management, and Outcomes

OBJECTIVE

To understand the clinical significance, hemodynamic presentation, management, and outcomes of patients presenting with saddle pulmonary embolism (PE).

METHODS

All patients with saddle PE diagnosed at Mayo Clinic in Rochester, Minnesota, from January 1, 1999, through December 31, 2014, were included in this study. These patients were age and simplified Pulmonary Embolism Severity Index (sPESI) matched (1:1) to a nonsaddle PE cohort. Both groups were then classified into massive, submassive, and low-risk PE based on established criteria and compared for clinical presentation, management, and outcomes.

RESULTS

A total of 187 consecutive patients with saddle PE were identified. The saddle PE group presented more frequently with massive PE (31% vs 20%) and submassive PE (49% vs 32%), whereas low-risk PE was more common in the nonsaddle PE group (48% vs 20%). Systemic thrombolysis was used more frequently in the saddle PE group on admission (10% vs 4%; P=.04) and later during hospitalization (3.2% vs 0%; P=.03). Late major adverse events were similar in both groups except for mechanical ventilation (6% in saddle PE vs 1% in nonsaddle PE; P=.02). Overall in-hospital mortality did not differ between the 2 groups (4.3% in saddle PE vs 5.4% in nonsaddle PE; P=.81).

CONCLUSION

Although patients with saddle PE presented with higher rates of hemodynamic compromise and need for thrombolysis and mechanical ventilation, we found no difference in short-term outcomes compared with an age- and severity-matched nonsaddle PE cohort. Overall, in-hospital mortality was low in both groups.

Consequences of Venous Thromboembolism, Including Chronic Thromboembolic Pulmonary Hypertension

Venous thromboembolism includes both deep vein thrombosis and pulmonary embolism. They pose a significant risk for morbidity and mortality. In an appropriate clinical setting, invasive interventions, including administration of thrombolytics, anticoagulation, and placement of vena cava filter, are warranted. Bleeding, postthrombotic syndrome, recurrence, and filter-associated complications are few of the complications of this disease. More recently, chronic thromboembolic pulmonary hypertension has gained clinical interest in patients with pulmonary embolism and has warranted close follow-up.

Pulmonary embolism severity assessment and prognostication

For patients who have acute symptomatic pulmonary embolism (PE), risk of short-term death and adverse outcomes should drive the initial treatment decisions. Practice guidelines recommend that patients who have a high-risk of PE-related death and adverse outcomes, determined by the presence of haemodynamic instability (i.e., shock or hypotension), should receive systemically administered thrombolytic therapy. Intermediate-high risk patients might benefit from close observation, and some should undergo escalation of therapy beyond standard anticoagulation, particularly if haemodynamic deterioration occurs. Low-risk for adverse outcomes should lead to early hospital discharge or full treatment at home. Validated prognostic tools (i.e., clinical prognostic scoring systems, imaging studies, and cardiac laboratory biomarkers) assist with risk classification of patients who have acute symptomatic PE.

Predictive value of insufficient contrast medium filling in pulmonary veins in patients with acute pulmonary embolism

This study is to investigate the predictive value of insufficient contrast medium filling (ICMF) in patients with acute pulmonary embolism (PE).A total of 108 PE patients were enrolled and divided into group A and group B according to the presence of ICMF. PE index and ventricul araxial lengths were measured. Heart cavity volumes were examined and right ventricle (RV) to left ventricle (LV) diameter ratio (RV/LV(d)) and volume ratio (RV/LV(V)) and right atrium (RA) to left atrium (LA) volume ratio (RA/LA(V)) were calculated and compared. Group A was further divided into A1 and A2 based upon the pulmonary vein filling degree and each index was compared.There were no significant differences between group A and B in general condition. PE index of group A was higher than that of group B. LA and LV in group A were smaller than that of group B, whereas RA in group A was larger than that of group B. RV/LV(d), RV/LV(V), and RA/LA(V) in group A were significantly larger than that of group B. Embolism index of group A2 was higher than that of groupA1, but without statistical significant difference. LA in group A2 was smaller than that of group A1, whereas RA, RV/LV(d), and RV/LV(V) were larger than that of group A1, all with significant differences.PE increased with serious ICMF in pulmonary veins could be used as an indicator for risk stratification in patients with acute PE.

"Systemic strategy at the patient's service": a congress report on supportive care in oncology

None.

Ultrasound Assisted Catheter-Directed Thrombolysis of Acute Pulmonary Embolism: A Review of Current Literature

Pulmonary embolism continues as a very common and also presumably life-threatening disorder. For affected individuals with intermediate- as well as high-risk pulmonary embolism, catheter-based revascularization procedures have developed a possible substitute for systemic thrombolysis or for surgical embolectomy. Ultrasound-assisted catheter-directed thrombolysis is an innovative catheter-based approach; which is the main purpose of the present review article. Ultrasound-assisted catheter-directed thrombolysis is much more efficacious in reversing right ventricular dysfunction as well as dilatation in comparison to anticoagulation alone in individuals at intermediate risk. However, a direct comparison of ultrasound-assisted thrombolysis with systemic thrombolysis or surgical thrombectomy is not available. Ultrasound-assisted thrombolysis with early intrapulmonary thrombolytic bolus could also be successful in high-risk patients, but unfortunately, data from randomized trials is limited. This review article recapitulates existing information on ultrasound-assisted thrombolysis for acute pulmonary embolism.

Advanced Cardiopulmonary Support for Pulmonary Embolism

Management of high-risk pulmonary embolism (PE) requires an understanding of the pathophysiology of PE, options for rapid clot reduction, critical care interventions, and advanced cardiopulmonary support. PE can lead to rapid respiratory and hemodynamic collapse via a complex sequence of events leading to acute right ventricular failure. Importantly, reduction in pulmonary vascular resistance must be accomplished either by systemic thrombolytics, catheter directed thrombolytics, endovascular clot extraction, or surgical embolectomy. There are important advances in these techniques all of which have a niche role in the cardiopulmonary stabilization of critically ill patient with PE. Critical care support surrounding the above interventions is necessary. Maintenance of systemic perfusion and cardiac output may require careful titration of vasopressors, inotropes, and preload. Extreme caution should be taken with approach to intubation and positive pressure ventilation. A hemodynamically neutral induction with preparations for circulatory collapse should be the goal. Once intubated, the effect of positive pressure on pulmonary vascular resistance and right ventricular hemodynamics is necessary. Veno-arterial extra corporeal membrane oxygenation plays an increasingly important role in the stabilization of the hemodynamically collapsed patient who either has a contraindication to systemic lytics, failed systemic lytics, or requires a bridge to surgical or catheter embolectomy. Veno-arterial extra corporeal membrane oxygenation has also been used alone to stabilize the circulation until hemodynamics normalize on anticoagulation and has also been used in tenuous patient as a safety net for endovascular procedures.

Thromboembolic complications after an ankle joint open fracture in a patient with a history of deep vein thrombosis in the lower limbs

A 55-year-old patient was admitted to the Department of Orthopedics due to an open fracture in the right ankle joint. On the seventh day of hospitalization the patient experienced a transient ischemic attack. During the next day, dyspnea, chest pain and a ‘rider’ type pulmonary embolism in the pulmonary trunk occluding both pulmonary arteries and its branches were diagnosed. The patient was transferred to the Department of Cardiac Surgery. He underwent pulmonary embolectomy for massive pulmonary, right and left atrial embolism, and left ventricular embolism. ASD II was closed during this procedure. Ultrasonography with Doppler was performed 6 days after the surgery and revealed deep vein thrombosis, so the patient was transferred to the Department of Vascular Surgery for temporary inferior vena cava filter placement at the time of orthopedic surgery. The next day after implantation of the filter, the lower limb was operated on, and 14 days after orthopedic surgery, the vena cava filter was removed.

The use of veno-venous extracorporeal membrane oxygenation following thrombolysis for massive pulmonary embolism

A 59-year-old man was diagnosed with a massive pulmonary embolism. Despite thrombolysis there were two episodes of cardiac arrest and following recovery of spontaneous circulation profound cardiorespiratory failure ensued. An extracorporeal membrane oxygenation retrieval team initiated veno-venous extracorporeal membrane oxygenation on site to facilitate transfer to the extracorporeal membrane oxygenation centre. An excellent outcome is reported in the short term. This represents one of the few published cases of veno-venous extracorporeal membrane oxygenation for a massive pulmonary embolism following thrombolysis.

[Posttraumatic thromboembolic complications: Incidence, risk factors, pathophysiology and prevention]

Venous thromboembolism (VTE) remains a major challenge in critically ill patients. Subjects admitted in intensive care unit (ICU), in particular trauma patients, are at high-risk for both deep vein thrombosis (DVT) and pulmonary embolism (PE). The rate of symptomatic PE in injured patients has been reported previously ranging from 1 to 6%. The high incidence of posttraumatic venous thromboembolic events is well known. In fact, major trauma is a hypercoagulable state. Several factors placing the individual patient at a higher risk for the development of DVT and PE have been suggested: high ISS score, meningeal hemorrhage and spinal cord injuries have frequently been reported as a significant risk factor for VTEs after trauma. Posttraumatic pulmonary embolism traditionally occurs after a period of at least 5 days from trauma. The prevention can reduce the incidence and mortality associated with the pulmonary embolism if it is effective. There is no consensus is now available about the prevention of venous thromboembolism in trauma patients.

Comparison of PESI, echocardiogram, CTPA, and NT-proBNP as risk stratification tools in patients with acute pulmonary embolism

OBJECTIVE

The aim of this study is to prospectively assess the diagnostic accuracy of pulmonary embolism severity index, echocardiogram, computed tomography pulmonary angiogram (CTPA), and N-terminal pro b-type natriuretic peptide (NT-proBNP) for predicting adverse events in acute pulmonary embolism patients.

METHODS

Thirty consecutive acute pulmonary embolism patients were included in this study. Combined adverse events consisted of in-hospital death or use of escalation of care including cardiopulmonary resuscitation, mechanical ventilation, vasopressor therapy, or secondary thrombolysis during hospital stay.

RESULTS

The outcomes were met in 30% of patients. Qanadli index (a measure of clot burden on CTPA) and NT-proBNP were significantly higher in patients with adverse events than those without (p=0.005 and p=0.009, respectively). PESI had moderate positive correlation with right ventricular dysfunction (RVD) (r=0.449, p=0.013) but there was no significant difference in PESI between patients with and without adverse events (p=0.7). Receiver operating characteristic analysis indicated that Qanadli index was the best predictor of adverse events with area under the curve (AUC) of 0.807 (95% CI: 0.651-0.963) with a negative predictive value (NPV) of 100% and positive predictive value (PPV) of 47.4% at cut-off value of 19. Right ventricle to left ventricle ratio on CTPA was found to predict RVD with AUC of 0.94 (95% CI: 0.842-1.000), NPV (77.8%), and PPV (95.2%) at cut-off value at 1.15.

CONCLUSION

Qanadli index is more accurate predictor of adverse events than pulmonary embolism severity index, NT-proBNP, and RVD on echocardiogram and CTPA.

The association of blood urea nitrogen levels with mortality in acute pulmonary embolism

BACKGROUND

The aim of this study was to investigate the association of BUN levels with in-hospital and long-term adverse clinical outcomes in acute pulmonary embolism (APE) patients treated with tissue-plasminogen activator (t-PA).

METHODS

This retrospective study included 252 consecutive confirmed APE patients treated with t-PA. An admission BUN of 34.5 mg/dL was identified through an ROC analysis as an optimal cutoff value to predict the in-hospital mortality with 85% sensitivity and 91% specificity (AUC: 0.91; 95% CI: 0.84-0.96; P<.001).

RESULTS

Our study showed that an increase in BUN levels was independently associated with a high risk of in-hospital all-cause mortality, low admission systolic blood pressure, use of inotropic drugs, and cardiogenic shock. In-hospital mortality rates were 51.1% in higher BUN group, and 1.9% in lower BUN group (P<.001).

CONCLUSION

In this study, elevated admission BUN level was found to be a predictor of all-cause in-hospital mortality. BUN testing is commonly part of the basic metabolic panel; and it can be used to detect high-risk patients with APE, and it bears little risk, is inexpensive, and easy to perform.

Circulatory collapse, right ventricular dilatation, and alveolar dead space: A triad for the rapid diagnosis of massive pulmonary embolism

A triad of circulatory collapse, right ventricular dilatation, and large alveolar dead space is proposed for the rapid diagnosis and treatment of massive pulmonary embolism. A 17year-old female on oral contraceptives collapsed at home becoming incoherent with shallow breathing. Paramedics initiated mechanical chest compression and transported the patient to our emergency department, arriving minimally responsive with undetectable blood pressure but having positive corneal reflexes and bradycardia with wide QRS. The trachea was intubated and goal-directed echocardiography revealed marked right ventricular dilatation with septal flattening. The arterial PCO₂ was 40mmHg with an end-tidal PCO₂ of 8mmHg, revealing a large alveolar dead space. Persistent hypotension, bradycardia, and fading alertness despite epinephrine and norepinephrine infusions prompted resumption of chest compression. Intravenous alteplase (10mg bolus over 10min followed by 90mg over 110min) begun 125min after collapse improved hemodynamic function within 10min allowing discontinuation of chest compression. Five and a half hours after starting alteplase, the patient was hemodynamically stable and had normal end-tidal PCO₂. A CT-angiogram showed the pulmonary arteries free of emboli but a thrombus in the right common iliac vein. The patient recovered fully and was discharged home on warfarin 8days later. Based on this and other reports, we propose a triad of circulatory collapse, right ventricular dilatation, and large alveolar dead space for the rapid diagnosis and treatment of massive pulmonary embolism, with systemic fibrinolysis as the first-line intervention.

The role of computed tomography in the diagnosis of acute and chronic pulmonary embolism

Pulmonary embolism (PE) is a potentially life threatening condition requiring adequate diagnosis and treatment. Computed tomography pulmonary angiography (CTPA) is excellent for including and excluding PE, therefore CT is the first-choice diagnostic imaging technique in patients suspected of having acute PE. Due to its wide availability and low invasiveness, CTPA tends to be overused. Correct implementation of clinical decision rules in diagnostic workup for PE improves adequate use of CT. Also, CT adds prognostic value by evaluating right ventricular (RV) function. CT-assessed RV dysfunction and to lesser extent central emboli location predicts PE-related mortality in normotensive and hypotensive patients, while PE embolic obstruction index has limited prognostic value. Simple RV/left ventricular (LV) diameter ratio measures >1.0 already predict risk for adverse outcome, whereas ratios <1.0 can safely exclude adverse outcome. Consequently, assessing the RV/LV diameter ratio may help identify patients who are potential candidates for treatment at home instead of treatment in the hospital. A minority of patients develop chronic thromboembolic pulmonary hypertension (CTEPH) following acute PE, which is a life-threatening condition that can be diagnosed by CT. In proximal CTEPH, involving the more central pulmonary arteries, thrombectomy usually results in good outcome in terms of both functional status and long-term survival rate. CT is becoming the imaging method of choice for diagnosing CTEPH as it can identify patients who may benefit from thrombectomy. New CT developments such as distensibility measurements and dual-energy or subtraction techniques may further refine diagnosis and prognosis for improved patient care.

Perioperative anesthetic management for renal cell carcinoma with vena caval thrombus extending into the right atrium: case series

Renal cell carcinoma has a tendency for vascular invasion and may extend into the inferior vena cava and even into the right-sided cardiac chambers. It has been reported that nephrectomy with thrombectomy can provide immediate palliation of symptoms with 5-year survival rates of up to 72% in the absence of nodal or distant metastasis. The location of the tumor dictates the anesthetic and surgical approach, as extension into the heart often necessitates cardiac surgical involvement. Renal cell carcinoma with vena cava tumor thrombus extending into the right cardiac chamber usually requires cardiopulmonary bypass and occasionally deep hypothermic circulatory arrest for surgical resection, and anesthetic approach should be tailored to each individual case. Thorough preoperative evaluation and the commitment of a multidisciplinary surgery team are indispensable.

Relation Among Clot Burden, Right-Sided Heart Strain, and Adverse Events After Acute Pulmonary Embolism

Computed tomography pulmonary angiogram (CTPA) provides a volumetric assessment of clot burden in acute pulmonary embolism (PE). However, it is unclear if clot burden is associated with right-sided heart strain (RHS) or adverse clinical events (ACE). We prospectively enrolled Emergency Department patients with PE (in CTPA) from 2008 to 2011. We assigned 1 to 9 points as clot burden score, based on whether emboli were saddle, central, lobar, segmental, and subsegmental. We evaluated a novel score (the "CT-PASS") based on the sum (in millimeters) of the largest filling defects in the right and left pulmonary vasculature. Our primary outcome was RHS, defined by imaging (echocardiography or CTPA) or cardiac biomarkers. Our secondary outcomes included 5-day ACE. We included 271 patients (50% women), with a mean age of 59 ± 17 years. Based on CTPA, 131 patients (48%) had central PE (clot burden score ≥5 points). The median CT-PASS was 9.1 mm (interquartile range 4.9 to 16.4). In univariate analysis, higher clot burden (highest quartile CT-PASS) was associated with RHS (p = 0.003). In multivariate analysis, after adjusting for RHS, age, and gender, central PE (odds ratio [OR] 2.92, 95% confidence interval [CI] 1.10 to 7.81) and CT-PASS >20 mm (OR 3.54, 95% CI 1.39 to 8.97) were significantly associated with ACE. However, this association of central PE with ACE was not statistically significant after excluding patients with shock index >1 (OR 2.56, 95% CI 0.62 to 10.64). In conclusion, highest quartile CT-PASS was associated with RHS and central PE and ACE, but this association was not statistically significant in hemodynamically stable PE [corrected].

Gene Expression Profiling of Pulmonary Artery in a Rabbit Model of Pulmonary Thromboembolism

Acute pulmonary thromboembolism (PTE) refers to the obstruction of thrombus in pulmonary artery or its branches. Recent studies have suggested that PTE-induced endothelium injury is the major physiological consequence of PTE. And it is reasonal to use PTE-induced endothelium injury to stratify disease severity. According to the massive morphologic and histologic findings, rabbit models could be applied to closely mimic the human PE. Genomewide gene expression profiling has not been attempted in PTE. In this study, we determined the accuracy of rabbit autologous thrombus PTE model for human PTE disease, then we applied gene expression array to identify gene expression changes in pulmonary arteries under PTE to identify potential molecular biomarkers and signaling pathways for PTE. We detected 1343 genes were upregulated and 923 genes were downregulated in PTE rabbits. The expression of several genes (IL-8, TNF-α, and CXCL5) with functional importance were further confirmed in transcript and protein levels. The most significantly differentially regulated genes were related to inflammation, immune disease, pulmonary disease, and cardiovascular diseases. Totally 87 genes were up-regulated in the inflammatory genes. We conclude that gene expression profiling in rabbit PTE model could extend the understanding of PTE pathogenesis at the molecular level. Our study provides the fundamental framework for future clinical research on human PTE, including identification of potential biomarkers for prognosis or therapeutic targets for PTE.

Relationship between serum betatrophin levels and the first-phase of glucose-stimulated insulin secretion

AIMS

To examine circulating betatrophin concentrations in subjects with different glucose tolerance status and to investigate the relationship between serum betatrophin levels and first-phase of glucose-stimulated insulin secretion.

METHODS

Serum betatrophin concentrations were measured in 110 age- and sex-matched subjects: 47 newly diagnosed type 2 diabetes mellitus (T2DM), 29 impaired glucose tolerance (IGT) and 34 normal glucose tolerance (NGT). Oral glucose tolerance test and intravenous glucose tolerance test were performed to assess glucose tolerance and first-phase of glucose-stimulated insulin secretion.

RESULTS

Serum betatrophin levels were significantly higher in the T2DM and IGT group than in the NGT group (2.10±1.16ng/mL vs 0.77±0.44ng/mL, 1.73±1.28ng/mL vs 0.77±0.44ng/mL; P<0.01). The AIR and AUC among the three groups showed a progressive decrease from the NGT to IGT group with the lowest value in the T2DM group (P<0.01). Betatrophin were found to be positively correlated with BMI, waist circumference (WC), homeostatic model assessment of insulin resistance (HOMA-IR) and triglyceride (TG), and inversely associated with HDL-c (all P<0.01), but not significantly correlated with 0-10min insulin the area under the curve (AUC) and acute insulin response (AIR) (P>0.05). Stepwise multiple regression analysis showed that HOMA-IR and TG were independently related to betatrophin (P<0.05).

CONCLUSION

Serum betatrophin concentrations were higher in T2DM and IGT, and were closely related to glucolipid disorder, insulin resistance, but not related to the first-phase of glucose-stimulated insulin secretion.

Diagnosis, prognosis and therapeutic management of acute pulmonary embolism

Pulmonary embolism (PE) is a leading cause of mortality worldwide. Recognizing PE and administering anticoagulants can significantly improve patient outcomes by reducing mortality rates and preventing recurrent events. For more than 50 years, standard therapy has involved parenteral anticoagulation followed by long-term therapy with the vitamin K antagonist warfarin. However, management of warfarin therapy is challenging due to its narrow therapeutic range and interactions with genetic and environmental factors. Direct oral anticoagulants (DOACs) have been developed to simplify anticoagulation and avoid the concerns associated with warfarin. DOACs are administered at a fixed dosage without routine monitoring and have few drug interactions. In recent years, DOACs have received FDA approval for the treatment of acute deep venous thrombosis (DVT) and PE based on the results of well-conducted clinical trials. This review discusses approaches to the diagnosis and treatment of PE and the use of DOACs as an alternative to warfarin treatment for the management of the disease. While many of the indications for DOACs and concepts discussed apply to both DVT and PE, our focus will be acute PE.

Thrombolytic Therapy for Massive Pulmonary Embolism in a Patient With a Known Intracranial Tumor

The objective was to describe and review the use of thrombolytic therapy in a patient with an intracranial tumor and massive pulmonary embolism. This is the first reported case of a patient with a known glioblastoma multiforme and massive pulmonary embolism who was successfully treated with alteplase. Pulmonary embolism was demonstrated by a ventilation-perfusion scan and transthoracic echocardiogram with repeat studies demonstrating resolution of the thromboembolism and reperfusion of pulmonary vasculature. A review of the literature revealed that the incidence of intracranial hemorrhage with thrombolysis is <3% and compares favorably with the much higher mortality rate of 25% to ≥50% in patients with hemodynamically unstable pulmonary emboli. The benefit of thrombolysis may outweigh the risks of intracranial hemorrhage in these patients, and careful consideration for its use in these patients is warranted.

Syncope as a presentation of acute pulmonary embolism

PURPOSE

Syncope is an atypical presentation for acute pulmonary embolism (APE). There are conflicting data concerning syncope and prognosis of APE.

PATIENTS AND METHODS

One hundred and seventy-nine consecutive patients aged 22-96 years (median, 68 years) with APE were retrospectively enrolled in the study.

RESULTS

Prevalence of syncope was 13% (n=23) at the time of presentation. Compared to patients without syncope, those with syncope had a higher rate of central embolism (83% vs 43%, respectively, P=0.002), right ventricular dysfunction (91% vs 68%, P=0.021), and troponin positivity (80% vs 39%, P=0.001) but not 30-day mortality (13% vs 10%, P=0.716). Multivariate analysis showed that central localization (odds ratio: 9.08) and cardiac troponin positivity (odds ratio: 4.67) were the independent correlates of the presence of syncope in the patients with APE. Frequency of cardiopulmonary disease was lower, and duration from symptom onset to hospital admission was shorter in patients with syncope (P=0.138 and 0.118, respectively), although not significant.

CONCLUSION

Syncope most likely represents an intermediate condition between massive APE and hypotension. In APE patients with syncope, the prognosis seems to depend on the underlying pathology, the patient's age, comorbidities and duration from symptom onset to hospital admission, and the use of thrombolytic therapy.

Post-Pleuropneumonectomy Herniation of Liver Mimicking Major Pulmonary Embolism

Following right-sided pneumonectomy and hemidiaphragm resection in a 58-year-old man with epithelioid mesothelioma, acute respiratory insufficiency and life-threatening circulatory collapse developed after a forced Valsalva maneuver. Major pulmonary embolism was diagnosed on clinical grounds, however computed tomography revealed herniation of the liver into the right hemithorax.

Surgical Embolectomy in Acute Massive Pulmonary Embolism

Acute pulmonary embolism is a serious condition and despite diagnostic and therapeutic advances, mortality is still high. Anticoagulation, thrombolytic therapy, catheter embolectomy, and open pulmonary embolectomy are therapeutic options. Surgical embolectomy was considered the management of last resort, but recent studies show the effectiveness of this therapeutic modality. We reviewed our 7-year experience of pulmonary embolectomy in patients with acute massive pulmonary embolism from 1997 to 2004. Eleven patients underwent open embolectomy, 7 (64%) were male, and the mean age was 45.6 years. Pulmonary embolism occurred after major surgery in 5 patients (46%), 2 were diagnosed with malignancy and spinal cord injury, and no risk factors were detected in 4. The diagnosis was made by spiral computed tomography alone in 4 patients, and by angiography in 7. Cardiac arrest occurred in 3 patients preoperatively; 2 of them survived. Open pulmonary embolectomy is the most effective treatment for acute massive pulmonary embolism. Cardiac arrest is the worst prognostic factor. Less aggressive clot evacuation in patients who are diagnosed late appears to be effective in minimizing postoperative hemoptysis.

Catheter-Directed Therapy in Acute Pulmonary Embolism with Right Ventricular Dysfunction: A Promising Modality to Provide Early Hemodynamic Recovery

BACKGROUND Catheter-directed therapy (CDT) for pulmonary embolism (PE) is considered as an alternative to systemic thrombolysis (ST) in patients with hemodynamically unstable acute PE who are considered at high bleeding risk for ST. We aimed to evaluate the efficacy and safety of CDT in the management of acute PE with right ventricular dysfunction (RVD). The primary outcomes were mortality, clinical success, and complications. Secondary outcomes were change in hemodynamic parameters in the first 24 hours following the procedure. MATERIAL AND METHODS Medical records of consecutive patients diagnosed as having acute massive or submassive PE with accompanying RVD treated by immediate CDT at our institution from January 2007 to January 2014 were reviewed. Patient characteristics, mortality, achievement of clinical success, and minor and major bleeding complications were analyzed in the overall study group, as well as massive vs. submassive PE subgroups. Change in hemodynamic parameters in the second, eighth, and 24th hours after the CDT procedure were also analyzed. RESULTS The study included 15 consecutive patients (M/F=10/5) with a mean age of 54.2 ± 16.6 years who underwent immediate CDT. Nine of the patients had submassive PE, and 6 had massive PE. In-hospital mortality rate was 13.3% (95% CI, 0.04-0.38). One major, but not life-threatening, bleeding episode was evident in the whole group. Hemodynamic parameters were stabilized and clinical success was achieved in 14/15 (93.3%; 95% CI, 70.2-98.8) of the patients in the first 24 hours. Notably, the hemodynamic recovery was significantly evident in the first 8 hours after the procedure. CONCLUSIONS CDT is a promising treatment option for patients with acute PE with RVD with no fatal bleeding complication. In experienced centers, CDT should be considered as a first-line treatment for patients with acute PE and RVD and contraindications for ST, with the advantage of providing early hemodynamic recovery.

Comparison of efficacy of different treatments for pulmonary embolism

An optimal therapy for pulmonary embolism (PE) was explored by comparing three different methods in order to alleviate the sufferings of PE patients and reduce the mortality. Eighty patients with PE diagnosed by computed tomography angiography (CTA) were treated with thrombolysis, anticoagulation only, or surgery/intervention. The clinical efficacy of different treatments were compared and analyzed. Twenty-four out of the 26 patients (92%) in anticoagulation only group showed improvement in CTA and clinical presentations, which was significantly higher than that in the thrombolysis group (87%, n=39, P<0.05). However, there was no significant difference in the rate of mortality between thrombolysis group and anticoagulation only group. In the surgery/interventional group (n=15), the success rate was 47%, and the mortality rate was 14%. Both of them were significantly different from those in thrombolysis and anticoagulation only groups (both P<0.05). Log-rank analysis of the data of 5-year follow-up revealed that the survival time in surgery/intervention group was significantly shorter than in the other two groups (P<0.05). It was suggested that it is of importance to choose the appropriate therapeutic regimen for PE patients. Mortality may be reduced and prognosis may be improved with anticoagulation only and thrombolysis therapy.

Potential role of systemic thrombolysis in acute submassive intermediate risk pulmonary embolism: review and future perspectives

Submassive (intermediate risk) pulmonary embolism (PE) continues to be a significantly morbid disease process that remains unrecognized, inadequately risk stratified and suboptimally treated. Appropriate early clinical and imaging-based risk stratification represents the cornerstone for adequate therapeutic decision making, particularly for the selection of candidates who may benefit the most from systemic thrombolysis. The relevance of estimating clinical prognostic scores, in combination with imaging data, for accurate assessment of right ventricular function and laboratory biomarkers, indicative of myocardial injury for identification of normotensive patients at intermediate risk for an adverse short-term outcome are emphasized in this review. Recent clinical trials have demonstrated improvement in hemodynamics and mortality with the use of systemic thrombolysis among intermediate risk patients; however, it came at the cost of a significantly increased risk of major bleeding. Catheter-based therapies have garnered considerable clinical interest in recent years; of particular note is the ultrasound accelerated catheter-directed thrombolysis which has emerged as a novel and attractive alternative therapeutic modality with an increasing number of single center studies and ongoing randomized trials. Our review focuses on the major trials and studies involved in submassive PE in the recent literature including the role of thrombolytic therapy. We include major trials with reasonable sample size and extensive review of the potential side effects, such as major bleeding.

Risk stratification of patients with acute symptomatic pulmonary embolism

Patients with acute symptomatic pulmonary embolism (PE) who present with arterial hypotension or shock have a high risk of death (high-risk PE), and treatment guidelines recommend strong consideration of thrombolysis in this setting. For normotensive patients diagnosed with PE, risk stratification should aim to differentiate the group of patients deemed as having a low risk for early complications (all-cause mortality, recurrent venous thromboembolism, and major bleeding) (low-risk PE) from the group of patients at higher risk for PE-related complications (intermediate-high risk PE), so low-risk patients could undergo consideration of early outpatient treatment of PE and intermediate-high risk patients would undergo close observation and consideration of thrombolysis. Clinicians should also use risk stratification and eligibility criteria to identify a third group of patients that should not undergo escalated or home therapy (intermediate-low risk PE). Such patients should initiate standard therapy of PE while in the hospital. Clinical models [e.g., Pulmonary Embolism Severity Index (PESI), simplified PESI (sPESI)] may accurately identify those at low risk of dying shortly after the diagnosis of PE. For identification of intermediate-high risk patients with acute PE, studies have validated predictive models that use a combination of clinical, laboratory and imaging variables.

Ventilation/Perfusion SPECT lung scintigraphy and computed tomography pulmonary angiography in patients with clinical suspicion of pulmonary embolism

The aim was to compare ventilation/perfusion SPECT lung scintigraphy (V/Q-SPECT) and computed tomography pulmonary angiography (CTPA) in patients with suspicion of pulmonary embolism (PE).

MATERIAL AND METHODS

This prospectively designed study included 53 patients with intermediate or high clinical probability of PE. A V/Q-SPECT and CTPA was performed on all patients. The V/Q-SPECT was interpreted according to the European Association of Nuclear Medicine and Molecular Imaging (EANMMI) guidelines. CTPA was reported as positive, negative, or indeterminate.

RESULTS

CTPA was positive in 22 cases, negative in 28, and indeterminate in 3. V/Q-SPECT was positive in 27 cases, negative in 24, and non-diagnostic in 2. In the 22 with positive CTPA, V/Q-SPECT was positive in 18, negative in 3, and non-diagnostic in 1. In the 28 with negative CTPA, V/Q-SPECT was positive in 8, negative in 19, and non-diagnostic in 1. In the 3 with indeterminate CTPA, V/Q-SPECT was positive in 1 and negative in 2. In the 2 non-diagnostic cases V/Q-SPECT, CTPA was positive in 1 and negative in one. In the 10 high clinical probabilities, CTPA and V/Q-SPECT were positive in 7, negative in 2, and in 1, CTPA was positive and V/Q-SPECT negative. In the 38 intermediate probability group, CTPA and V/Q-SPECT were positive in 11, negative in 17, with CTPA negative and V/Q-SPECT positive in 8, and in 2 CTPA was positive and V/Q-SPECT negative. The results show that V/Q-SPECT detected PE in 5 patients more than CTPA.

CONCLUSION

Our results show a 77% concordance of both techniques. Overall V/Q-SPECT detected PE in 18% more patients than CTPA in the intermediate group. Both techniques have a complementary role when a diagnosis cannot be made with one of them.

Diagnostic implications of computed tomography pulmonary angiography in patients with pulmonary embolism

INTRODUCTION:

Pulmonary embolism (PE) is a serious cardiovascular and pulmonary complication worldwide. We aimed to assess the implications of different computed tomography pulmonary angiography (CTPA) parameters in patients with acute PE.

METHODS:

A retrospective observational study to include patients presented with clinical suspicious of PE who underwent CTPA was conducted. Patients' demographics, clinical presentation, risk factors, laboratory investigations, management, and outcome were analyzed. Computed tomography findings included clot burden (Qanadli score [QS]) and right ventricular dysfunction (RVD) parameters.

RESULTS:

A total of 45 patients with radiologically confirmed diagnosis of PE were included in the study; of these patients, 8 (17.8%) died during the hospital course. Patients who died were 13 years older than those who survived, and the mortality rate was significantly higher in patients with cancer. The two groups were comparable for cardiovascular parameters. The mean clot burden (QS) was 19.5 ± 11.3 points and 53% of patients had QS >18 points. Obesity (52.4% vs. 12.5%; P = 0.01), hypertension (54.4% vs. 23.8%; P = 0.03), and median D-dimer levels (7.8 vs. 3.4; P = 0.03) were significantly higher in patients with QS >18. Among right ventricular (RV) dysfunction parameters, only higher RV/left ventricular (LV) ratio (P = 0.001) and bowing of interventricular septum (P = 0.001) were associated with higher QS. A significant positive correlation was found between RV short axis (r = 0.499, P = 0.001), RV/LV ratio (r = 0.592, P = 0.001), and pulmonary artery (PA) diameter (r = 0.301, P = 0.04) with the PA clot burden. Receiver operating characteristic curve for clot burden showed a cutoff value of 17.5 points to accurately predict RV dysfunction.

CONCLUSIONS:

Clot burden >18 is associated with RV dysfunction in patients with acute PE. Echocardiography and RVD parameters showed no correlation with in-hospital deaths. CTPA has clinicoradiological implications for risk stratification in PE patients. As the sample size is small, our findings warrant further larger prospective studies.

MiR-28-3p as a potential plasma marker in diagnosis of pulmonary embolism

OBJECTIVES

Circulating miRNAs have been reported to have potential in detecting various diseases. However, few studies explored differentially expressed miRNAs in plasma of patients with pulmonary embolism (PE). Our study is to identify plasma miRNAs which can serve as potential biomarkers of PE.

MATERIALS AND METHODS

Exiqon miRCURY Ready-to-Use PCR Human panel I+II V1.M was conducted to identify differently expressed miRNAs in pooled plasma samples of PE patients compared with normal controls. Expressions of identified miRNAs were assessed in 37 PE patients as well as matched normal individuals followed by validation on six Beagle dogs by quantitative reverse transcription polymerase chain reaction (qRT-PCR).

RESULTS

Twelve miRNAs were identified from the screening phase. Moreover, miR-134, previously reported related with PE, and hypoxia-induced miR-210 were also submitted to the validation phase. Only miR-28-3p was found significantly elevated in the plasma of PE patients. Compared with the level of plasma miR-28-3p of the dogs before PE, the elevated miR-28-3p did not alter significantly at 1, 2, 4 and 6h after PE. The area under the receiver operating characteristic (ROC) curve of plasma miR-28-3p was 0.792 (95% confidence interval: 0.689-0.896). KEGG pathway analysis showed that miR-28-3p might involve in PE related pathways such as inositol phosphate metabolism and phosphatidylinositol signaling system.

CONCLUSION

Our study indicated that elevated plasma miR-28-3p could be used as a non-invasive and stable biomarker in the detection of PE. Further researches on the miRNA are warranted.

Delayed anticoagulation is associated with poor outcomes in high-risk acute pulmonary embolism

PURPOSE

Early diagnosis and timely treatment are essential to improve the outcomes of pulmonary embolism (PE), but no study has investigated the impact of anticoagulation timing on clinical outcomes in high-risk acute PE patients. We analyzed the relationship between early anticoagulation initiation and in-hospital mortality in high-risk acute PE patients at the intensive care unit (ICU) of a teaching hospital.

MATERIALS AND METHODS

Seventy-three PE patients admitted to the ICU were included in this retrospective study. Demographic, clinical, radiological, and therapeutic data were collected on ICU admission, and the timings of diagnosis and anticoagulation initiation were analyzed.

RESULTS

The number of survivors was 67. The median time from hospital arrival to the start of anticoagulation therapy was significantly lower in survivors (3.6 [2.6-5.0] hours) than nonsurvivors (5.7 [4.5-14.9] hours; P = .03). However, the median time required to achieve a therapeutic anticoagulation level was comparable between survivors and nonsurvivors (12.0 [9.5-19.5] vs 16.4 [10.7-27.4] hours; P = .488). Ventilatory support and vasopressor use were found to be associated with higher in-hospital mortality.

CONCLUSIONS

Delayed anticoagulation is an important prognostic factor of poor outcomes in high-risk acute PE patients.