Abstract
BACKGROUND:
Optimal management of acute pulmonary embolism requires expertise offered by multiple subspecialties. As such, pulmonary embolism response teams (PERTs) have increased in prevalence, but the institutional consequences of a PERT are unclear.
METHODS:
We compared all patients that presented to our institution with an acute pulmonary embolism in the 3 years prior to and 3 years after the formation of our PERT. The primary outcome was in-hospital pulmonary embolism-related mortality before and after the formation of the PERT. Sub-analyses were performed among patients with elevated-risk pulmonary embolism.
RESULTS:
Between August 2012 and August 2018, 2042 patients were hospitalized at our institution with acute pulmonary embolism, 884 (41.3%) pre-PERT implementation and 1158 (56.7%) post-PERT implementation, of which 165 (14.2%) were evaluated by the PERT. There was no difference in pulmonary embolism-related mortality between the two time periods (2.6% pre-PERT implementation vs 2.9% post-PERT implementation, P = .89). There was increased risk stratification assessment by measurement of cardiac biomarkers and echocardiograms post-PERT implementation. Overall utilization of advanced therapy was similar between groups (5.4% pre-PERT implementation vs 5.4% post-PERT implementation, P = 1.0), with decreased use of systemic thrombolysis (3.8% pre-PERT implementation vs 2.1% post-PERT implementation, P = 0.02) and increased catheter-directed therapy (1.3% pre-PERT implementation vs 3.3% post-PERT implementation, P = 0.05) post-PERT implementation. Inferior vena cava filter use decreased after PERT implementation (10.7% pre-PERT implementation vs 6.9% post-PERT implementation, P = 0.002). Findings were similar when analyzing elevated-risk patients.
CONCLUSION:
Pulmonary embolism response teams may increase risk stratification assessment and alter application of advanced therapies, but a mortality benefit was not identified.
Keywords: Catheter-directed thrombolysis, Inferior vena cava filters, Pulmonary embolism, Response teams, Systemic thrombolysis
INTRODUCTION
Acute pulmonary embolism is increasing in incidence, with persistent poor outcomes among patients at elevated risk.1–3 Recently, there has been a growing armamentarium of treatment options for pulmonary embolism with an increasing body of evidence supporting various anticoagulation strategies, catheter-directed thrombolysis (CDT), numerous systemic thrombolysis regimens, and mechanical circulatory support.4–8 The associated increase in the complexity of pulmonary embolism management has necessitated the development of pulmonary embolism response teams (PERTs). Although the composition of PERTs vary by institution, they generally include health professionals from varying specialties with expertise in the care of acute pulmonary embolism and offer rapid evaluation and management for intermediate and high-risk patients.9 The impact of PERTs also include downstream institutional effects, such as increased pulmonary embolism education and management awareness.10,11,12 Data supporting multidisciplinary, rapid response teams for other disease processes such as acute aortic syndrome, stroke, and inpatient response teams have demonstrated benefits.13–15 However, the majority of reports to date have been single-armed, single-center case series with recent calls for additional data that focus on outcomes related to PERTs.16–18 Therefore, we evaluated the effects in assessment, management, and outcomes of all patients with acute pulmonary embolism hospitalized at our institution before and after the implementation of our PERT.
METHODS
The structure and logistics of our PERT, MASCOT (Massive And Submassive Clot Oncall Team), have been previously described in detail.16 Briefly, MASCOT is a multidisciplinary team that includes specialists from cardiology, vascular medicine, pulmonary, critical care, hematology, interventional radiology, and cardiac surgery. Our hospital offers a large gamut of pulmonary embolism treatments. Increased awareness was promoted by presentations given to various departments within the hospital and to affiliated hospitals regarding the team’s availability and management of acute pulmonary embolism.
In this study, we compared all patients admitted to our academic, tertiary care center, with an acute pulmonary embolism in the 3 years prior to (August 2012 through July 2015) and the 3 years following (August 2015 through July 2018) the implementation of the MASCOT. Patients with a formal consult by the MASCOT were entered into a prospective registry. Acute pulmonary embolism patients that did not have a formal MASCOT consult were identified by searching an internal billing claims database. The electronic medical records were then reviewed to confirm the diagnosis of acute pulmonary embolism and to identify patient demographics, comorbidities, clinical characteristics, pulmonary embolism severity, and outcomes. The study was approved by the Beth Israel Deaconess Medical Center Institutional Review Board.
The primary outcome was in-hospital pulmonary embolism-related mortality. Patients with hypotension, shock, or who received mechanical ventilatory or circulatory support due to an acute pulmonary embolism were considered to be at high risk. Those that did not meet the criteria for high risk but did have evidence of right ventricular strain on computed tomography or echocardiography, or had elevated cardiac biomarkers were considered to be at intermediate risk, and the remainder of patients were considered to be at low risk. Given that the majority of patients evaluated by MASCOT were patients at elevated risk, a secondary analysis of patients was performed limited to patients with an intermediate- or high-risk pulmonary embolism that required intensive care unit (ICU) level of care at some point during their hospitalization. The cause of death for each patient was independently adjudicated by 3 investigators (KS, TM, AB). Those patients with mortality classified as definitely related or likely related to pulmonary embolism were considered to have had a pulmonary embolism-related death. Secondary outcomes included assessment of risk stratification measures, utilization of advanced therapies for acute pulmonary embolism inferior vena cava (IVC) filter use, major bleeding, length of stay, and 90-day readmissions. Major bleeding was considered fatal bleeding, intracranial bleed, symptomatic bleed in a critical area or organ, bleeding requiring transfusion of 2 or more units of packed red blood cells, or a procedure to evaluate or intervene on a bleed.19
Statistical Analysis
All metric and normally distributed variables are reported as mean ± standard deviation; non-normally distributed variables are presented as median (interquartile range). Categorical variables are presented as frequency and percentage. Between-group differences in baseline characteristics and outcomes were assessed using Fisher’s exact or Chi2 tests for categorical variables and Student-t or Wilcoxon rank sum tests for continuous variables.
The primary exposure was time of admission depending on presence of the MASCOT (prior to August 2015 vs after). We used separate multivariable regression models to describe exposure-outcome relationships. Logistic regression was used for all outcomes. Logistic regression was not performed if events per variable included were less than 5.20,21 Variables were selected a priori based on prior literature and clinical relevance.22–25 The analyses were repeated including only elevated-risk patients.
RESULTS
Total Cohort Demographics and Clinical Characteristics
During the study period, 2042 patients were hospitalized with acute pulmonary embolism, 884 (41.3%) pre-PERT implementation and 1158 (56.7%) post-PERT implementation, of which 165 (14.2%) were evaluated by the MASCOT. Baseline characteristics of patients pre- and post-PERT implementation are presented in Table 1.
Table 1.
Patient Demographics and Baseline Characteristics (N = 2042)
| (n, if >10 data points unavailable) | Pre-PERT Implementation n = 884 | Post-PERT Implementation n = 1158 | P Value |
|---|---|---|---|
| Age | 62.3 ± 16.5 | 63.6 ± 16.3 | .08 |
| Female sex | 458 (52.3) | 623 (53.9) | .47 |
| Smoking status (2003) | .98 | ||
| Never smoker | 449 (52.0) | 596 (52.3) | |
| Former smoker | 306 (35.4) | 398 (34.9) | |
| Current smoker | 109 (12.6) | 145 (12.7) | |
| Comorbidities | |||
| Median Charlson Comorbidity Index | 4 (1–6) | 4 (2–6) | .27 |
| Hypertension | 457 (51.7) | 599 (51.7) | 1.00 |
| Hyperlipidemia | 343 (38.8) | 419 (36.2) | .23 |
| Diabetes without complications | 118 (13.3) | 176 (15.2) | .25 |
| Diabetes with complications | 41 (4.6) | 52 (4.5) | .92 |
| Mild chronic kidney disease | 28 (3.2) | 44 (3.8) | .47 |
| Severe chronic kidney disease | 33 (3.7) | 46 (4.0) | .82 |
| End-stage renal disease on HD | 9 (1.0) | 15 (1.3) | .68 |
| Congestive heart failure | 70 (7.9) | 106 (9.2) | .34 |
| Myocardial infarction | 78 (8.8) | 85 (7.3) | .25 |
| Peripheral artery disease | 16 (1.8) | 58 (5.0) | <.001 |
| Cerebrovascular accident | 51 (5.8) | 95 (8.2) | .04 |
| Pulmonary hypertension | 8 (0.9) | 21 (1.8) | .09 |
| Chronic obstructive pulmonary disease | 85 (9.6) | 106 (9.2) | .76 |
| Mild liver disease | 32 (3.6) | 19 (1.6) | .006 |
| Moderate to severe liver disease | 17 (1.9) | 32 (2.8) | .25 |
| Malignancy, any | 277 (31.3) | 338 (29.2) | .31 |
| Rheumatologic disease | 46 (5.2) | 51 (4.4) | .40 |
| Thrombophilia, any | 34 (3.8) | 39 (3.4) | .63 |
| Surgery within 90 days | 45 (5.1) | 65 (5.6) | .62 |
| Trauma within 90 days | 11 (1.2) | 23 (2.0) | .22 |
| Hospitalization within 90 days | 40 (4.5) | 111 (9.6) | <.001 |
| Pregnant | 8 (1.7) | 8 (1.3) | .61 |
| Prior venous thromboembolism | |||
| Within 30 days | 134 (15.2) | 170 (14.7) | .80 |
| Within 90 days | 94 (10.6) | 130 (11.2) | .72 |
| Home medications | |||
| OCP or hormone replacement | 40 (4.5) | 53 (4.6) | 1.00 |
| Antiplatelets | 267 (30.2) | 347 (30.0) | .92 |
| Anticoagulation | 90 (10.2) | 139 (12.0) | .20 |
| Beta blockers | 242 (27.4) | 330 (28.5) | .59 |
| Anti-hypertensives | 394 (44.6) | 528 (45.6) | .65 |
| Transfer from outside hospital (2005) | 282 (32.5) | 398 (35.0) | .23 |
HD = hemodialysis; OCP = oral contraceptive pill; PERT = pulmonary embolism response team.
Patients were more likely to have been hospitalized in the 90-day period prior to the acute pulmonary embolism post-PERT implementation (4.5% vs 9.6%; P < .001). Peripheral artery disease and prior cerebrovascular accident were more prevalent post-PERT implementation. A greater proportion of pulmonary embolisms were classified as intermediate-risk post-PERT implementation (33.8% vs 49.8%, P < .001) with a similar number of high-risk pulmonary embolisms at pre- and post-PERT implementation (4.8% vs 3.8%). Lower extremity venous ultrasounds, cardiac biomarkers assessment, and transthoracic echocardiograms were more frequently performed post-PERT implementation (Table 2).
Table 2.
Patient Pulmonary Embolism Characteristics (N = 2042)
| (n, if >10 data points unavailable) | Pre-PERT Implementation n = 884 | Post-PERT Implementation n = 1158 | P Value |
|---|---|---|---|
| Most proximal location of PE on CT (1985) | .002 | ||
| RV | 7 (0.8) | 7 (0.6) | |
| Saddle thrombus | 82 (9.7) | 62 (5.5) | |
| Main pulmonary artery | 134 (15.8) | 226 (19.9) | |
| Distal to main pulmonary artery | 608 (71.7) | 824 (72.5) | |
| RV strain on CT (1888) | 164 (20.0) | 244 (22.8) | .14 |
| Lower extremity ultrasound (2017) | |||
| Performed | 499 (57.4) | 728 (63.5) | .006 |
| Positive for concomitant deep vein thrombosis | 279 (39.0) | 384 (48.9) | <.001 |
| Location of deep vein thrombosis | .05 | ||
| Proximal | 218 (82.0) | 270 (75.2) | |
| Distal | 48 (18.0) | 89 (24.8) | |
| HR (1906) | 92.7 ± 20.6 | 93.2 ± 20.3 | .55 |
| SBP(1901) | 125.0 ± 22.3 | 127.3 ± 23.7 | .04 |
| 02 supplementation (1958) | .68 | ||
| None | 503 (61.0) | 706 (62.3) | |
| Nasal cannula | 241 (29.2) | 329 (29.0) | |
| Non-rebreather | 24 (2.9) | 25 (2.2) | |
| NIPPV | 6 (0.7) | 13 (1.1) | |
| Intubation | 50 (6.1) | 61 (5.4) | |
| Troponin T evaluated | 589 (66.6) | 942 (81.4) | < .0001 |
| Troponin T value (1531) | 0.3 ± 4.2 | 0.1 ± 1.2 | .27 |
| proBNP evaluated | 359 (40.6) | 797 (68.8) | < .0001 |
| proBNP value (1156) | 2400.8 ± 5963.1 | 2596.2 ± 6979.0 | .65 |
| TTE performed | 427 (49.0) | 674 (58.7) | <.001 |
| RV enlargement | 189 (44.9) | 244 (37.9) | .02 |
| RV hypokinesis | 175 (41.5) | 222 (34.3) | .02 |
| PE severity | <.001 | ||
| Low risk | 538 (61.4) | 532 (46.4) | |
| Intermediate risk | 296 (33.8) | 571 (49.8) | |
| High risk | 42 (4.8) | 44 (3.8) | |
BNP = brain natriuretic peptide; CT = computed tomography; HR = heart rate; NIPPV = non-invasive positive pressure ventilation; O2 = oxygen; PE = pulmonary embolism; PERT = pulmonary embolism response team; RV = right ventricular; SBP = systolic blood pressure; TTE = transthoracic echocardiogram.
Additional patient characteristics and outcomes among those evaluated by the MASCOT are presented in Supplementary Tables 1–3 Table Supplementary 1 (available online). Table Supplementary 2.
Total Cohort Management and Outcomes
There was no significant difference in initial anticoagulation strategy pre- and post-PERT implementation (Table 3). Overall utilization of advanced therapy was similar between groups (5.4% pre-PERT implementation vs 5.4% post-PERT implementation, P = 1.0), with decreased use of systemic thrombolysis (3.8% pre-PERT implementation vs 2.1% post-PERT implementation, P = .02) and increased utilization of catheter-directed therapy (1.3% pre-PERT implementation vs 3.3% post-PERT implementation, P = .05) post-PERT implementation (Figure 1). Inferior vena cava filter use decreased post-PERT implementation (10.7% pre-PERT implementation vs 6.9% post-PERT implementation, P = .002). There was no difference in pulmonary embolism-related mortality pre- and post-PERT implementation (2.6% pre-PERT implementation vs 2.9% post-PERT implementation, P = .89). There were also no differences in bleeding rate, median length of stay, mortality unrelated to pulmonary embolism, overall survival to discharge, or readmissions (Table 4). Direct oral anticoagulants were more frequently utilized post-PERT implementation at time of discharge (13.8% pre-PERT implementation vs 40.4% post-PERT implementation, P < .001).
Table 3.
Patient Management and Outcomes (n = 2042)
| (n, if >10 data points unavailable) | Pre-PERT Implementation n = 884 | Post-PERT Implementation n = 1158 | P Value |
|---|---|---|---|
| Initial anticoagulation | .007 | ||
| None | 48 (5.4) | 70 (6.0) | |
| IV heparin | 654 (74.0) | 861 (74.4) | |
| LMWH | 164 (18.6) | 182 (15.7) | |
| DOAC | 6 (0.7) | 30 (2.6) | |
| Other | 12 (1.4) | 15 (1.3) | |
| Advanced therapy | |||
| Systemic thrombolysis | 34 (3.8) | 24 (2.1) | .02 |
| CDT-US | 8 (0.9) | 33 (2.8) | .002 |
| CDT alone | 2 (0.2) | 2 (0.2) | 1.000 |
| Mechanical embolectomy | 2 (0.2) | 3 (0.3) | 1.000 |
| Surgical thrombectomy | 2 (0.2) | 1 (0.1) | .58 |
| ECMO | 4 (0.5) | 5 (0.4) | 1.00 |
| IVC filter placed | 95 (10.7) | 80 (6.9) | .002 |
| Major bleeding | 51 (5.8) | 81 (7.0) | .28 |
| Fatal bleed | 3 (0.3) | 2 (0.2) | .66 |
| Intracranial hemorrhage | 13 (1.5) | 14 (1.2) | .70 |
| Bleed requiring ≥ 2 units pRBCs | 33 (3.7) | 53 (4.6) | .38 |
| Bleed requiring intervention | 14 (1.6) | 32 (2.8) | .10 |
| Length of stay (median, IQR) | 4 (2–9) | 5 (2–11) | .39 |
| Survival to discharge, overall | 824 (93.2) | 1086 (93.8) | .65 |
| Low-risk pulmonary embolism | 516 (95.9) | 516 (97.0) | .41 |
| Intermediate-risk pulmonary embolism | 274 (92.6) | 535 (93.7) | .57 |
| High-risk pulmonary embolism | 28 (66.7) | 25 (56.8) | .38 |
| Cause of death | .86 | ||
| Pulmonary embolism main cause of death | 12 (20.0) | 14 (19.4) | |
| Death likely due to pulmonary embolism | 13 (21.7) | 17 (23.6) | |
| Death unlikely due to pulmonary embolism | 30 (50.0) | 32 (44.4) | |
| Death unrelated to pulmonary embolism | 5 (8.3) | 9 (12.5) | |
| Readmission (n = 1954) | .26 | ||
| No | 589 (78.7) | 810 (75.4) | |
| Within 30 days | 119 (15.9) | 199 (18.5) | |
| Within 90 days | 40 (5.3) | 65 (6.1) | |
| Recurrent deep vein thrombosis | 9 (1.1) | 13 (1.2) | 1.00 |
| Recurrent pulmonary embolism | 9 (1.1) | 19 (1.7) | .26 |
| Long-term therapy | <.001 | ||
| Warfarin | 418 (51.0) | 288 (26.7) | |
| LMWH | 237 (28.9) | 283 (26.3) | |
| DOAC | 113 (13.8) | 435 (40.4) | |
| Other | 13 (1.6) | 5 (0.5) | |
| None | 39 (4.8) | 67 (6.2) |
CDT = catheter-directed thrombolysis; CDT-US = ultrasound-assisted catheter-directed thrombolysis; DOAC = direct oral anticoagulant; ECMO = extracorporeal membrane oxygenation; IV = intravenous; IVC = inferior vena cava; IQR = interquartile range; LMWH = low molecular weight heparin; pRBC = packed red blood cells.
Figure 1.
Outcomes in all patients admitted with an acute pulmonary embolism before and after PERT implementation. IVC = inferior vena cava; PERT = pulmonary embolism response team.
Table 4.
Comparison of pre- and post-PERT Implementation Outcomes, Multiple Imputation Analysis of All Patients (N = 2042)
| Adjusted Model* | |
|---|---|
| Any advanced therapy† | OR 1.09 (0.70–1.69), P = .716 |
| Any major bleeding | OR 1.23 (0.86–1.78), P = .261 |
| Survival to discharge | OR 1.16 (0.81–1.67), P = .418 |
| Pulmonary embolism-related mortality‡ | OR 0.83 (0.48–1.43), P = .494 |
| Readmission at 90 days§ | OR 1.22 (0.96–1.55), P = .102 |
| Recurrent venous thromboembolism (combined pulmonary embolism and deep vein thrombosis)§ | OR 1.49 (0.80–2.76), P = .206 |
OR = odds ratio; PERT = pulmonary embolism response team.
Adjusted for age, gender, hospitalization within 90 days, prior venous thromboembolism (combined deep vein thrombosis or pulmonary embolism) within 90 days, transfer from outside hospital, strain on transthoracic echocardiogram (right ventricular enlargement or hypokinesis; patients without transthoracic echocardiography assumed normal), Charlson Comorbidity Index, and any malignancy (hematologic, solid, or metastatic).
Includes systemic lytics, catheter-directed thrombolysis (combined), mechanical thrombectomy, and surgical thrombectomy.
Includes definite pulmonary embolism mortality and death likely due to pulmonary embolism.
Analysis of patients alive at discharge.
Elevated-Risk Patients
Of the 2042 patients admitted, 468 (22.9%) with intermediate or high-risk pulmonary embolism were cared for in the ICU and were included in the elevated-risk analysis. Prior to PERT implementation, there were 192 patients (21.7%), and after PERT implementation, there were 276 patients (23.8%). The MASCOT team evaluated 118 (42.8%) patients (Supplementary Table 4, available online). Pre-PERT implementation patients were more likely to have had recent surgery (4.2% vs 9.4%, P = .05) and a recent hospitalization (3.6% vs 16.3% P < .001). There was a similar distribution of pulmonary embolism severity (available online). Total advanced therapy utilized was similar between groups (23.4% pre-PERT implementation vs 22.4% post-PERT implementation, P = .82) with lower use of systemic thrombolysis (17.2% pre-PERT implementation vs 8.3% post-PERT implementation, P = .006) and higher catheter-directed therapy use (5.2% pre-PERT implementation vs 13.8% post-PERT implementation, P = .003) post-PERT implementation (Supplementary Table 6 [available online], Figure 2). Inferior vena cava filter placement decreased after PERT implementation (26.0% pre-PERT implementation vs 12.4% post-PERT implementation, P = < .001). There was no difference in major bleeding, length of stay, overall survival to discharge, pulmonary embolism-related mortality, or readmissions in unadjusted or adjusted analysis (Supplementary Table 7, available online).
Figure 2.
Outcomes in elevated-risk patients with an acute pulmonary embolism before and after PERT implementation. IVC = inferior vena cava; PERT = pulmonary embolism response team.
DISCUSSION
We report the largest investigation of patients with acute pulmonary embolism pre- and post-PERT implementation. Our study demonstrated increased use of risk stratification strategies post-PERT implementation. There was similar overall utilization of advanced therapies, with increased use of CDT and decreased systemic thrombolysis post-PERT implementation. Additionally, IVC filter placement decreased post-PERT implementation, particularly in the elevated-risk population. However, there was no difference in overall mortality, pulmonary embolism-related mortality, or major bleeding events in the total cohort or the elevated-risk group.
There have been several recent comparative studies published evaluating outcomes in certain pulmonary embolism populations within a center; however, our study is the first to evaluate all patients hospitalized with acute pulmonary embolism.26–30 Although PERTs generally focus on elevated-risk patients, our primary analysis included all patients at our hospital with acute pulmonary embolism to identify the effect of the PERT on the institutional care of pulmonary embolism patients as a whole. Our PERT provided cross-department education, using handouts and frequent presentations reviewing risk stratification and potential treatment options throughout the institution. Prior data suggest a PERT has an effect on pulmonary embolism knowledge within the institution that could lead to changes in care beyond the patients evaluated by the PERT alone.10,11 Although we did not demonstrate a reduction in overall or pulmonary embolism-related mortality or major bleeding, there was an increase in risk assessment, reduction in IVC filter use, and change in mode of thrombolytic administration.
The effect of a PERT on mortality has been evaluated in prior studies in select populations,28–30 but only one of which demonstrated a reduction in mortality.26 Chaudhury et al investigated 769 patients that were diagnosed by computed tomography at their center only, over a 3-year period, and demonstrated a decrease in mortality in the entire cohort (8.5% vs 4.7%, P = .03) and in those with intermediate or high-risk pulmonary embolism (10.0% vs 5.3% (P = .02).26 It is difficult to make a direct comparison to our study. Our study spans twice the time period, includes more than twice the number of patients, and includes outside transfers. Only 13% of patients in the study by Chaudhury et al had low-risk pulmonary embolism, compared with 42% in our study. Additionally, their sub-analysis of intermediate- and high-risk patient is likely biased for improved mortality post-PERT implementation, as there was a higher frequency of troponin evaluation, increasing the proportion of patients that were classified as intermediate-risk pulmonary embolism. It is also unclear how many of those patients required ICU admission and the rate of pulmonary embolism-related mortality. Other studies evaluating the effect of PERTs have not demonstrated a mortality benefit.28,30
There are, however, other potential important effects of a PERT beyond mortality. Risk stratification in acute pulmonary embolism is essential for appropriate patient selection for advanced therapy. We did note cardiac biomarker evaluation, echocardiograms, and lower extremity ultrasound performed were increased post-PERT implementation. Additionally, there was a higher proportion of patients diagnosed with intermediate-risk pulmonary embolism. Although patients may have been sicker post-PERT implementation, increased assessment of right ventricular strain also likely contributed to this change, given the 16% increase in patients with intermediate-risk pulmonary embolism post-PERT implementation.
It has been indicated that the PERT may be a vehicle for increasing interventions. Prior studies have demonstrated a more than doubling in the use of advanced therapy; however, there was no increase in overall advanced therapy utilization with our PERT.27,30 We did find a transition in mode of delivery of thrombolytic, with a more than tripling in use of CDT post-PERT implementation in the elevated-risk cohort. This transition in mode of delivery of thrombolysis may be partially attributable to the US Food and Drug Administration approval of the EKOS catheter (ultrasound-facilitated, catheter-directed, low-dose thrombolysis), which occurred in 2014. The increase in CDT may also reflect the ability of the team to help select patients that are more appropriate for such therapy (minimizing exposure to systemic thrombolysis), and to coordinate the procedure between the various specialties involved. Despite the decrease in systemic thrombolysis, there was no difference in major bleeding, which has been demonstrated in a recent observational study comparing systemic to catheter-directed thrombolysis.31 Inferior vena cava filter placement was more than halved post-PERT implementation in the elevated-risk group with no difference in the remainder of the cohort. There was a national trend toward decrease IVC filter utilization,32 and reduction has been demonstrated in prior evaluations of PERT teams as well.26
It is expected that effects of PERTs will differ based on institutions. It remains unclear if the potential effects of a PERT are secondary to the multidisciplinary team approach or the availability of a dedicated service experienced with managing pulmonary embolism (eg, a vascular medicine consultative service). One recent study demonstrated improved pulmonary embolism outcomes in centers with high pulmonary embolism volumes.33 Some institutions may have had well-established protocols and consult mechanisms prior to initiation of a PERT, and thus less significant effects would be expected. Quality improvements, efficiencies in utilization of inpatient and intensive care unit beds, transfer for advanced pulmonary embolism management, patient and provider satisfaction, and cognitive interchange between specialties may be additional potential benefits of a multidisciplinary approach to care.34 Such nuances are difficult to capture in traditional data collection.
LIMITATIONS
Our data are limited to a single center, including the resources of its electronic medical records. Evaluation of time to initiation of therapy was inadequate due to lack of medication administration records available online for the majority of the study period. It is possible some patients with acute pulmonary embolism were not included if appropriate billing did not occur; however, all patients that did have a billing code for pulmonary embolism were confirmed with review of medical record to have an acute event. As noted in the discussion, some of the pre- to post-PERT implementation changes may be partially explained by advancement in pulmonary embolism management, including growing availability of catheter-directed therapy, more widespread utilization of direct oral anticoagulants, and increasing awareness of the potential dangers of IVC filter use. The impact of such trends is difficult to fully quantify in our analysis.
CONCLUSIONS
Acute pulmonary embolism remains a common condition that portends a poor prognosis in elevated risk patients. Pulmonary embolism is well suited for a multidisciplinary, rapid response team approach to care, given the multiple specialties involved in the care of pulmonary embolism and the potential for early decompensation. Pulmonary embolism response teams may increase knowledge within an institution and offer improved application of advanced therapies; however, the overall mortality benefit remains unclear. Further studies that include multiple centers are warranted to assess the effects of PERTs on outcomes, particularly utilization of advanced therapies and mortality.
Supplementary Material
CLINICAL SIGNIFICANCE.
There was increased utilization of risk stratification tools with the development of a pulmonary embolism response team.
The presence of a pulmonary embolism response team decreased inferior vena cava filter use and systemic thrombolysis, and increased utilization of catheter-directed thrombolysis.
There was no difference in pulmonary embolism-related or overall mortality with the presence of a pulmonary embolism response team.
Footnotes
Conflict of Interest: DSP is a consultant for Abbott Vascular, Abiomed, Boston Scientific, Medtronic, NuPulseCV, and Teleflex. KAB has served as a consultant for Bristol Myers Squibb. EAS has received research grants to BIDMC: AstraZeneca, BD Bard, Boston Scientific, Cook Medical, CSI, Medtronic, Philips, and the University of California, San Francisco; is a consultant for BD Bard, CSI, Janssen, Medtronic, and Philips; and is on the speaking bureau for BD Bard, Cook Medical, and Medtronic. The remaining authors have no relevant disclosures.
SUPPLEMENTARY DATA
Supplementary data to this article can be found online at https://doi.org/10.1016/j.amjmed.2020.03.058.
References
- 1.Keller K, Hobohm L, Ebner M, et al. Trends in thrombolytic treatment and outcomes of acute pulmonary embolism in Germany. Eur Heart J. 2020;41:522–9. [DOI] [PubMed] [Google Scholar]
- 2.Bikdeli B, Wang Y, Jimenez D, et al. Pulmonary embolism hospitalization, readmission, and mortality rates in US older adults, 1999–2015. JAMA. 2019;322:574–6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Secemsky E, Chang Y, Jain CC, et al. Contemporary management and outcomes of patients with massive and submassive pulmonary embolism. Am J Med. 2018;131:1506–14. [DOI] [PubMed] [Google Scholar]
- 4.Raskob GE, van Es N, Verhamme P, et al. Edoxaban for the treatment of cancer-associated venous thromboembolism. N Eng J Med. 2018;378:615–24. [DOI] [PubMed] [Google Scholar]
- 5.Piazza G, Hohlfelder B, Jaff MR, et al. A prospective, single-arm, multicenter trial of ultrasound-facilitated, catheter-directed, low-dose fibrinolysis for acute massive and submassive pulmonary embolism: the SEATTLE II study. JACC Cardiovasc Interv. 2015;8:1382–92. [DOI] [PubMed] [Google Scholar]
- 6.Tu T, Toma C, Tapson VF, et al. A prospective, single-arm, multicenter trial of catheter-directed mechanical thrombectomy for intermediate-risk acute pulmonary embolism: the FLARE study. JACC Cardiovasc Interv. 2019;12:859–69. [DOI] [PubMed] [Google Scholar]
- 7.Kiser TH, Burnham EL, Clark B, et al. Half-dose versus full-dose alteplase for treatment of pulmonary embolism. Crit Care Med. 2018;46:1617–25. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Meneveau N, Guillon B, Planquette B, et al. Outcomes after extracorporeal membrane oxygenation for the treatment of high-risk pulmonary embolism: a multicentre series of 52 cases. Eur Heart J. 2018;39:4196–204. [DOI] [PubMed] [Google Scholar]
- 9.Barnes GD, Kabrhel C, Courtney DM, et al. Diversity in the pulmonary embolism response team model: an organizational survey of the national PERT consortium members. Chest. 2016;150:1414–7. [DOI] [PubMed] [Google Scholar]
- 10.Elbadawi A, Wright C, Patel D, et al. The impact of a multi-specialty team for high risk pulmonary embolism on resident and fellow education. Vasc Med. 2018;23:372–6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Brailovsky Y, Kunchakarra S, Lakhter V, et al. Pulmonary embolism response team implementation improve awareness and education among the house staff and faculty. J Thromb Thrombolysis. 2019;49:54–8. [DOI] [PubMed] [Google Scholar]
- 12.Rosovsky R, Zhao K, Sista A, Rivera-Lebron B, Kabrhel C. Pulmonary embolism response teams: purpose, evidence for efficacy, and future research directions. Res Pract Thromb Haemost. 2019;3:315–30. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Andersen ND, Ganapathi AM, Hanna JM, Williams JB, Gaca JG, Hughes GC. Outcomes of acute type A dissection repair before and after implementation of a multidisciplinary thoracic aortic surgery program. J Am Coll Cardiol. 2014;63:1796–803. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Nazir FS, Petre I, Dewey HM. Introduction of an acute stroke team: an effective approach to hasten assessment and management of stroke in the emergency department. J Clin Neurosci. 2009;16:21–5. [DOI] [PubMed] [Google Scholar]
- 15.Solomon RS, Corwin GS, Barclay DC, Quddusi SF, Dannenberg MD. Effectiveness of rapid response teams on rates of in-hospital cardiopulmonary arrest and mortality: a systematic review and meta-analysis. J Hosp Med. 2016;11:438–45. [DOI] [PubMed] [Google Scholar]
- 16.Carroll BJ, Pemberton H, Bauer KA, et al. Initiation of a multidisciplinary, rapid response team to massive and submassive pulmonary embolism. Am J Cardiol. 2017;120:1393–8. [DOI] [PubMed] [Google Scholar]
- 17.Kabrhel C, Rosovsky R, Channick R, et al. A multidisciplinary pulmonary embolism response team: initial 30-month experience with a novel approach to delivery of care to patients with submassive and massive pulmonary embolism. Chest. 2016;150: 384–93. [DOI] [PubMed] [Google Scholar]
- 18.Giri JS, Piazza G. A midterm report card for pulmonary embolism response teams. Vasc Med. 2018;23:72–4. [DOI] [PubMed] [Google Scholar]
- 19.Schulman S, Kearon C. Definition of major bleeding in clinical investigations of antihemostatic medicinal products in non-surgical patients. J Thromb Haemost. 2005;3:692–4. [DOI] [PubMed] [Google Scholar]
- 20.Vittinghoff E, McCulloch CE. Relaxing the rule of ten events per variable in logistic and Cox regression. Am J Epidemiol. 2007;165:710–8. [DOI] [PubMed] [Google Scholar]
- 21.White IR, Royston P, Wood AM. Multiple imputation using chained equations: issues and guidance for practice. Stat Med. 2011;30:377–99. [DOI] [PubMed] [Google Scholar]
- 22.Goldhaber SZ, Visani L, De Rosa M. Acute pulmonary embolism: clinical outcomes in the International Cooperative Pulmonary Embolism Registry (ICOPER). Lancet. 1999;353:1386–9. [DOI] [PubMed] [Google Scholar]
- 23.Monreal M, Falgá C, Vilaseca B, et al. Clinical outcomes in cancer patients with concurrent venous thromboembolism: findings from the RIETE registry. Haematol Rep. 2005;1:64–5. [Google Scholar]
- 24.Jiménez D, Aujesky D, Moores L, et al. Simplification of the pulmonary embolism severity index for prognostication in patients with acute symptomatic pulmonary embolism. Arch Intern Med. 2010;170:1383–9. [DOI] [PubMed] [Google Scholar]
- 25.Spirk D, Husmann M, Hayoz D, et al. Predictors of in-hospital mortality in elderly patients with acute venous thrombo-embolism: the SWIss Venous ThromboEmbolism Registry (SWIVTER). Eur Heart J. 2012;33:921–6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Chaudhury P, Gadre SK, Schneider E, et al. Impact of multidisciplinary pulmonary embolism response team availability on management and outcomes. Am J Cardiol. 2019;124:1465–9. [DOI] [PubMed] [Google Scholar]
- 27.Wright C, Elbadawi A, Chen YL, et al. The impact of a pulmonary embolism response team on the efficiency of patient care in the emergency department. J Thromb Thrombolysis. 2019;48:331–5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28.Xenos ES, Davis GA, He Q, Green A, Smyth SS. The implementation of a pulmonary embolism response team in the management of intermediate- or high-risk pulmonary embolism. J Vasc Surg Venous Lymphat Disord. 2019;7:493–500. [DOI] [PubMed] [Google Scholar]
- 29.Jen W-Y, Kristanto W, Teo L, et al. Assessing the impact of a pulmonary embolism response team and treatment protocol on patients presenting with acute pulmonary embolism. Heart Lung Circ. 2020;29(3):345–53. [DOI] [PubMed] [Google Scholar]
- 30.Rosovsky R, Chang Y, Rosenfield K, et al. Changes in treatment and outcomes after creation of a pulmonary embolism response team (PERT), a 10-year analysis. J Thromb Thrombolysis. 2019;47:31–40. [DOI] [PubMed] [Google Scholar]
- 31.Beyer SE, Shanafelt C, Pinto DS, et al. Utilization and outcomes of thrombolytic therapy for acute pulmonary embolism: a nationwide cohort study. Chest. 2020;157(3):645–53. [DOI] [PubMed] [Google Scholar]
- 32.Kishore D, Horny M, Rosenkrantz AB, et al. State-level variation in inferior vena cava filter utilization across Medicare and commercially insured populations [e-pub ahead of print]. AJR Am J Roentgenol. 2019:1–8. 10.2214/AJR.18.20673. Accessed January 2, 2020. [DOI] [PubMed] [Google Scholar]
- 33.Jimenez D, Bikdeli B, Quezada A, et al. Hospital volume and outcomes for acute pulmonary embolism: multinational population based cohort study. BMJ. 2019;366:l4416. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34.Coylewright M, Mack MJ, Holmes DR Jr, O’Gara PT. A call for an evidence-based approach to the heart team for patients with severe aortic stenosis. J Am Coll Cardiol. 2015;65:1472–80. [DOI] [PubMed] [Google Scholar]
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