Management of Massive Pulmonary Embolism

Platelet glycoprotein Ibalpha gene polymorphism and massive or submassive pulmonary embolism

OBJECTIVE

The -5T/C polymorphism in the Kozak sequence of glycoprotein Ibalpha, a component of the platelet glycoprotein Ib-IX-V receptor complex, is associated with an increase in this receptor density on the surface of the platelet. This study was designed to investigate the effect of platelet glycoprotein Ibalpha Kozak polymorphism on the clinical presentation of the patients with acute pulmonary embolism.

METHODS

Forty-two patients with pulmonary embolism were genotyped for Kozak polymorphism of the glycoprotein Ibalpha by polymerase chain reaction/restriction fragment length polymorphism.

RESULTS

Carriers of the -5T/C polymorphism of glycoprotein Ibalpha were significantly over-represented in the patient group with clinically massive or submassive pulmonary embolism (odds ratio 5.5, 95% confidence interval 1.4 to 22.2, P = 0.023). Also the association between this polymorphism and massive or submassive pulmonary embolism still existed even after being adjusted for conventional risk factors.

CONCLUSION

The -5T/C polymorphism in the Kozak sequence of glycoprotein Ibalpha may present as a risk factor for clinical manifestation of pulmonary embolism in which clot burden plays an important role.

Rheolytic thrombectomy in patient with massive pulmonary embolism: a case report and review of literature

OBJECTIVE

Despite advances in management with thrombolytic therapy or open embolectomy, the mortality rate remains high in patients with massive pulmonary embolism (MPE).

BACKGROUND

We present a case of 51-year-female patient who collapsed while jogging and was brought to the Emergency Department. Upon arrival, she was found to have marked hypotension and hypoxia. EKG showed marked ST T abnormalities suggestive of anterior and lateral ischemia. Blood was drawn for labs. Patient received aspirin, heparin, and was transferred to cardiac catheterization laboratory.

METHODS

Coronary angiogram revealed normal epicardial coronaries. A pigtail catheter was inserted through right femoral vein and pulmonary angiogram was performed. It revealed bilateral MPE. Tissue plasminogen activator was initiated as per standard protocol. A 7-French aspiration catheter (Export, Medtronic Vascular, Santa Rosa, CA) was used without any success. Rheolytic thrombectomy (RT) (AngioJet, Possis, Minneapolis, MN) was performed successfully with adjunctive local and systemic thrombolytic therapy. Immediate pulmonary angiogram showed increased perfusion through right pulmonary artery. Her hemodynamic status improved significantly. Patient was discharged home after 8 days of hospitalization. Patient remains on lifelong anticoagulation therapy and she continues to remain stable at 20 months follow up.

CONCLUSIONS

RT with adjunctive localized and systematic thrombolytic therapy was performed successfully in this patient with MPE and significant hemodynamic compromise. In our patient who was very unstable from cardio-respiratory perspective with maximized hemodynamic support, RT device use was life saving. RT has an advantage of not dispersing emboli particles to the distal pulmonary circulation.

Combined clot fragmentation and aspiration in patients with acute pulmonary embolism

BACKGROUND

Massive angiographic pulmonary embolism (PE) with right ventricular dysfunction (RVD) is associated with a high early mortality rate. The therapeutic alternatives for this condition include thrombolysis, surgical embolectomy, or percutaneous mechanical thrombectomy (PMT). We describe our experience using PMT in patients with massive PE and RVD with unsuccessful thrombolysis, increased bleeding risk, or major contraindications for thrombolytic therapy.

METHODS

Clinical, hemodynamic, and angiographic parameters prior to and following PMT were evaluated. Our primary objective was to describe the incidence of in-hospital cardiovascular death, and of major and minor complications. Mid-term outcomes included analysis of occurrence of cardiovascular death, recurrent pulmonary embolism, change of New York Heart Association functional class, and hospital readmission.

RESULTS

From July 2004 to May 2007, 69 patients were referred to the cardiac catheterization laboratory with a diagnosis of acute PE, 18 of whom met the criteria for massive PE and are the subject of this study. All patients underwent thrombus fragmentation using a pigtail catheter that was complemented in 13 patients with thrombus aspiration. A percutaneous thrombectomy device (Aspirex; Straub Medical; Wangs, Switzerland) was used in 11 patients. Hemodynamic, angiographic, and blood oxygenation parameters improved after the procedure. A significant increase was observed for systolic systemic BP (74.3+/-7.5 mm Hg vs 89.4+/-11.3 mm Hg, p=0.001) [mean+/-SD], as was a decrease in mean pulmonary artery pressure (37.1+/-8.5 mm Hg vs 32.3+/-10.5 mm Hg , p=0.0001). The in-hospital major complications rate was 11.1%; one patient died from refractory shock, and one patient had intracerebral hemorrhage with minor neurologic sequelae. No cardiovascular deaths or recurrent pulmonary thromboembolism were documented during clinical follow-up (12.3+/-9.4 months).

CONCLUSIONS

In patients with massive PE, RVD and major contraindications to thrombolytic therapy, increased bleeding risk, failed thrombolysis, or unavailable surgical thrombectomy, PMT appears to be a useful therapeutic alternative.

Catheter Embolectomy for Acute Pulmonary Embolism

Massive pulmonary embolism (PE) is a life-threatening condition with a high early mortality rate due to acute right ventricular failure and cardiogenic shock. As soon as the diagnosis is suspected, an IV bolus of unfractionated heparin should be administered. In addition to anticoagulation, rapid initiation of systemic thrombolysis is potentially life-saving and therefore is standard therapy. Many patients with massive PE cannot receive thrombolysis because of an increased bleeding risk, such as prior surgery, trauma, or cancer. In these patients, catheter or surgical embolectomy are helpful for rapidly reversing right ventricular failure. Catheter thrombectomy appears to be particularly useful if surgical embolectomy is not available or the patient has contraindications to surgery. Although no controlled clinical trials are available, data from cohort studies indicate that the clinical outcomes after surgical and catheter embolectomy may be comparable.

Pulmonary Embolism in the Critically Ill

Pulmonary embolism in the critically ill requires considerations beyond anticoagulant therapy. Measurements of chamber size by echocardiography and CT and of circulating biomarkers identify higher-risk patients with moderate accuracy and may aid determination of patient acuity. Preserving right ventricular function requires judicious use of volume administration, vasopressor, and perhaps vasodilator therapies. Obstructing thrombus can be treated with fibrinolytic drugs, percutaneous instrumentation, or surgically, but these treatments may not be equally effective or safe. Anticoagulant therapy in critically ill patients is likely best administered IV. Bleeding complications should be assiduously sought but do not necessitate anticoagulant discontinuation in every case. The antidotes protamine, desmopressin acetate, factor VIII inhibitory bypass activity, and recombinant factor VIIa may each have a place in controlling anticoagulant-related bleeding. The grave prognosis of heparin-induced thrombocytopenia warrants close surveillance, with rapid switching to lepirudin, argatroban, or fondaparinux necessary if it is suspected. Retrievable vena cava filters can be lifesaving, and at least one type may be safely removed after residence of nearly 1 year.

Extracorporeal Life Support for Massive Pulmonary Embolism

BACKGROUND

Massive pulmonary embolism is frequently lethal because of acute irreversible pulmonary and cardiac failure. Extracorporeal life support (ECLS) has been used for cardiopulmonary failure in our institution since 1988, and we reviewed our experience with its use in the management of massive pulmonary emboli.

METHODS

We reviewed our complete experience with ECLS for massive pulmonary emboli from January 1992 through December 2005. The records of 21 patients were examined and data extracted.

RESULTS

During the study period, 21 patients received ECLS for massive pulmonary emboli. All patients were on vasoactive drugs, acidemic, and hypoxic at the time of institution of ECLS. Eight were in active cardiac arrest. Five were trauma patients, eight had recently undergone an operation, and six had a hypercoagulable disorder. Nineteen of the 21 patients were cannulated for venoarterial bypass and two were placed on venovenous bypass. The average duration of support for survivors was 5.4 days, ranging from 5 hours to 12.5 days. Emboli resolved with anticoagulation in 10 of 13 survivors and 4 of 13 survivors underwent surgical pulmonary embolectomy. Catastrophic neurologic events were the most common cause of mortality in our series; four patients died from intracranial hemorrhage. The overall survival rate was 62% (13/21).

CONCLUSIONS

We conclude that emergent ECLS provides an opportunity to improve the prognosis of an otherwise near-fatal condition, and should be considered in the algorithm for management of a massive pulmonary embolism in an unstable patient.

Catheter-tip embolectomy in the management of acute massive pulmonary embolism

Three catheter interventional techniques are currently available for removing or fragmenting pulmonary emboli: aspiration thrombectomy, fragmentation, and rheolytic thrombectomy. The investigators systematically reviewed all available published research related to the use of catheter-tip devices in patients with pulmonary emboli. Pooled data showed that clinical success with the Greenfield catheter occurred in 72 of 89 patients (81%) when used alone and in 19 of 19 patients (100%) when used in combination with thrombolytic agents. Fragmentation with standard catheters used alone (without thrombolytic agents) was reported in only 3 patients. Clinical success with standard angiographic catheters occurred in 15 of 21 patients (71%) when used in combination with systemic thrombolytic agents and in 115 of 121 patients (95%) when used with local infusions of thrombolytic agents. Data for the Amplatz catheter, the rheolytic Angiojet catheter, and the Hydrolyser catheter when used alone were sparse or absent. Clinical success when used in combination with thrombolytic agents occurred in 6 of 6 patients (100%) with the Amplatz catheter, in 20 of 23 patients (87%) with the Angiojet catheter, and in 19 of 20 patients (95%) with the Hydrolyser catheter. Minor bleeding at the insertion site among all patients, with and without thrombolytic agents, occurred in 29 of 348 patients (8%), and major bleeding at the insertion site occurred in 8 of 348 patients (2%). One patient experienced perforation of the right ventricle with the Greenfield catheter. None reported perforation of a pulmonary artery. In conclusion, all the devices analyzed in this study appear to be useful in the management of acute massive pulmonary emboli.

Saddle pulmonary embolism diagnosed by CT angiography: frequency, clinical features and outcome

OBJECTIVE

To assess the frequency, clinical presentation and outcome associated with saddle pulmonary embolism (PE) diagnosed by computed tomographic angiography (CTA).

PATIENTS

Retrospective review of 546 consecutive patients diagnosed to have acute PE by CTA from 1 September 2002 to 31 December 2003.

RESULTS

Fourteen of 546 patients (2.6%) had saddle PE; 10 were men (71%). None of these patients had pre-existing cardiopulmonary disease. Most common presenting symptoms included dyspnea (72%) and syncope (43%). Hypotension was documented in 2 patients (14%). The most common risk factor for PE was obesity (64%). CTA revealed saddle PE and additional filling defects in the main pulmonary arteries in all patients. Echocardiography was performed within 48 h of the PE diagnosis in 10 patients and revealed right ventricular dysfunction in 8 (80%). All patients were initially managed in the hospital, median length of stay of 4 days (range, 1-45 days). Standard anticoagulant therapy with heparin and warfarin was administered to all patients. Five patients (36%) received additional therapy; thrombolytic therapy was administered to 1 patient (7%) and 4 patients (29%) received an inferior vena cava filter. None of the patients died during their hospitalization. Four patients (29%) died following their hospitalization after intervals of 1, 5, 6, and 12 months, respectively. Causes of death were known in 3 patients, all of whom died from progressive malignancy.

CONCLUSION

Saddle PE in patients without pre-existing cardiopulmonary disease is associated with a relatively low in-hospital mortality rate and may not necessitate aggressive medical management.

Massive pulmonary embolus with hemodynamic compromise: therapeutic options

Recent advances in pharmacotherapeutics and interventional techniques have resulted in resurgence in interest regarding the optimal means of management of hemodynamically significant pulmonary embolic disease. However, these various techniques have many associated disadvantages, and it is of paramount importance that the responsible physician has a detailed understanding of each of these so that the appropriate intervention be requested and performed. By way of background discussion and relevant cases in point, we consider each of these management options in turn, with particular reference to the advantages, disadvantages, and application of each.

Massive Pulmonary Embolism

Background— Acute massive pulmonary embolism (PE) carries an exceptionally high mortality rate. We explored how often adjunctive therapies, particularly thrombolysis and inferior vena caval (IVC) filter placement, were performed and how these therapies affected the clinical outcome of patients with massive PE.

Methods and Results— Among 2392 patients with acute PE and known systolic arterial blood pressure at presentation, from the International Cooperative Pulmonary Embolism Registry (ICOPER), 108 (4.5%) had massive PE, defined as a systolic arterial pressure <90 mm Hg, and 2284 (95.5%) had non–massive PE with a systolic arterial pressure ≥90 mm Hg. PE was first diagnosed at autopsy in 16 patients (15%) with massive PE and in 29 patients (1%) with non–massive PE ( P <0.001). The 90-day mortality rates were 52.4% (95% CI, 43.3% to 62.1%) and 14.7% (95% CI, 13.3% to 16.2%), respectively. In-hospital bleeding complications occurred in 17.6% versus 9.7% and recurrent PE within 90 days in 12.6% and 7.6%, respectively ( P <0.001). In patients with massive PE, thrombolysis, surgical embolectomy, or catheter embolectomy were withheld in 73 (68%). Thrombolysis was performed in 33 patients, surgical embolectomy in 3, and catheter embolectomy in 1. Thrombolytic therapy did not reduce 90-day mortality (thrombolysis, 46.3%; 95% CI, 31.0% to 64.8%; no thrombolysis, 55.1%; 95% CI, 44.3% to 66.7%; hazard ratio, 0.79; 95% CI, 0.44 to 1.43). Recurrent PE rates at 90 days were similar in patients with and without thrombolytic therapy (12% for both; P =0.99). None of the 11 patients who received an IVC filter developed recurrent PE within 90 days, and 10 (90.9%) survived at least 90 days. IVC filters were associated with a reduction in 90-day mortality (hazard ratio, 0.12; 95% CI, 0.02 to 0.85).

Conclusions— In ICOPER, two thirds of the patients with massive PE did not receive thrombolysis or embolectomy. Counterintuitively, thrombolysis did not reduce mortality or recurrent PE at 90 days. The observed reduction in mortality from IVC filters requires further investigation.

Predictors of major hemorrhage following fibrinolysis for acute pulmonary embolism

One hundred four patients at Brigham and Women's Hospital who received alteplase for acute pulmonary embolism were evaluated. Major bleeding occurred in 20 patients (19.2%). The principal site of bleeding was unknown in 9 (45.0%), gastrointestinal in 6 (30.0%), retroperitoneal in 3 (15.0%), intracranial in 1 (5.0%), and splenic in 1 (5.0%). Independent predictors of major hemorrhage were the administration of catecholamines for systemic arterial hypotension (odds ratio [OR] 115, 95% confidence interval [CI] 9.4 to 1,410.9, p < 0.001), cancer (OR 16.0, 95% CI 3.2 to 80, p = 0.004), diabetes mellitus (OR 9.6, 95% CI 1.7 to 54, p = 0.010), and elevated international normalized ratio before fibrinolysis (OR 5.8, 95% CI 1.5 to 22, p = 0.012).