Risk Stratification in Acute Pulmonary Embolism
Risk Stratification in Acute Pulmonary Embolism
Objectives: Guidelines have recommended that risk stratification be performed in patients diagnosed with an acute pulmonary embolism (PE). No study has described the use of risk stratification in routine clinical practice. The purpose of this study was to measure the frequency and impact of risk stratification on treatment decisions and outcomes in patients admitted with acute PE.
Methods: A retrospective cohort study was conducted of all of the patients admitted with acute PE at two Geisinger community-based teaching hospitals between 2006 and 2011. Baseline demographics, vital signs, and relevant clinical variables were recorded. The Pulmonary Embolism Severity Index was calculated for each patient. Risk stratification was defined as the measurement of either a biomarker or an echocardiogram within 24 hours of admission. The outcomes measured were short-term adverse events (in-hospital mortality or need for intensive care) and 30-day mortality.
Results: The mean age for the study cohort (n = 889) was 61 ± 17 years and 52% were men. Overall, 59% of study subjects were risk stratified. The frequency of risk stratification did not change over time. Risk stratification was associated with assignment to a higher acuity of care and increased use of thrombolysis and inferior vena cava filter placement. When controlling for severity of illness, risk stratification was a significant predictor of worsened short-term adverse outcome (odds ratio 3.43, 95% confidence interval 1.75–6.74, P < 0.001) but was not associated with improved 30-day mortality (odds ratio 1.14, 95% confidence interval 0.66–1.95, P = 0.64).
Conclusions: Risk stratification is frequently performed in patients admitted with acute PE and has had a stable prevalence during a 5-year period. The use of risk stratification in acute PE is associated with assignment to higher levels of care and with more advanced treatments. Despite more intense treatment, risk stratification does not improve either short-term outcomes or 30-day mortality.
Pulmonary embolism (PE) is a commonly encountered condition, occurring in approximately 23 to 69/100,000 people per year in the United States. Overall mortality in individuals with acute PE is 5% to 15%, although outcomes vary substantially, depending upon underlying comorbidities and severity of presentation. Patients with PE complicated by cardiogenic shock have a mortality rate that approaches 30% to 60%. Although patients with acute PE who present with shock clearly have a significant risk of mortality and require intensive care, this subgroup accounts for a minority of patients with acute PE at presentation.
Hemodynamically stable patients with acute PE and evidence of right heart strain are more common than patients with PE and shock. These patients account for 30% to 55% of all of those with PE; moreover, these patients have an elevated risk of subsequent hemodynamic collapse or death compared with those with no evidence of right heart strain. In an effort to identify these at-risk patients, guidelines from both American and European societies have recommended that prognostic risk stratification, via clinical risk scores, echocardiography, or biomarkers play an integral part in the evaluation and management of patients diagnosed with an acute PE. The rationale for risk stratification is to identify a particular patient's risk of subsequent hemodynamic deterioration and death. In theory, this information could be used to both define the level of care a patient requires and identify those who may benefit from therapies beyond anticoagulation, such as systemic or catheter-directed thrombolysis or inferior vena cava (IVC) filters. Multiple reports describe the ability of clinical risk scoring systems, biomarkers, and echocardiography to positively and negatively predict the risk of adverse outcomes in individuals with acute PE. While acute PE risk stratification methods have been used to identify high- and low-risk patient populations for inclusion in clinical trials, to our knowledge no study has described the prevalence or impact of risk stratification in routine clinical practice. The purpose of the present study was to determine the frequency of risk stratification over time in patients in a large integrated healthcare system diagnosed as having acute PE and to assess whether risk stratification influenced treatment decisions and outcomes.
Abstract and Introduction
Abstract
Objectives: Guidelines have recommended that risk stratification be performed in patients diagnosed with an acute pulmonary embolism (PE). No study has described the use of risk stratification in routine clinical practice. The purpose of this study was to measure the frequency and impact of risk stratification on treatment decisions and outcomes in patients admitted with acute PE.
Methods: A retrospective cohort study was conducted of all of the patients admitted with acute PE at two Geisinger community-based teaching hospitals between 2006 and 2011. Baseline demographics, vital signs, and relevant clinical variables were recorded. The Pulmonary Embolism Severity Index was calculated for each patient. Risk stratification was defined as the measurement of either a biomarker or an echocardiogram within 24 hours of admission. The outcomes measured were short-term adverse events (in-hospital mortality or need for intensive care) and 30-day mortality.
Results: The mean age for the study cohort (n = 889) was 61 ± 17 years and 52% were men. Overall, 59% of study subjects were risk stratified. The frequency of risk stratification did not change over time. Risk stratification was associated with assignment to a higher acuity of care and increased use of thrombolysis and inferior vena cava filter placement. When controlling for severity of illness, risk stratification was a significant predictor of worsened short-term adverse outcome (odds ratio 3.43, 95% confidence interval 1.75–6.74, P < 0.001) but was not associated with improved 30-day mortality (odds ratio 1.14, 95% confidence interval 0.66–1.95, P = 0.64).
Conclusions: Risk stratification is frequently performed in patients admitted with acute PE and has had a stable prevalence during a 5-year period. The use of risk stratification in acute PE is associated with assignment to higher levels of care and with more advanced treatments. Despite more intense treatment, risk stratification does not improve either short-term outcomes or 30-day mortality.
Introduction
Pulmonary embolism (PE) is a commonly encountered condition, occurring in approximately 23 to 69/100,000 people per year in the United States. Overall mortality in individuals with acute PE is 5% to 15%, although outcomes vary substantially, depending upon underlying comorbidities and severity of presentation. Patients with PE complicated by cardiogenic shock have a mortality rate that approaches 30% to 60%. Although patients with acute PE who present with shock clearly have a significant risk of mortality and require intensive care, this subgroup accounts for a minority of patients with acute PE at presentation.
Hemodynamically stable patients with acute PE and evidence of right heart strain are more common than patients with PE and shock. These patients account for 30% to 55% of all of those with PE; moreover, these patients have an elevated risk of subsequent hemodynamic collapse or death compared with those with no evidence of right heart strain. In an effort to identify these at-risk patients, guidelines from both American and European societies have recommended that prognostic risk stratification, via clinical risk scores, echocardiography, or biomarkers play an integral part in the evaluation and management of patients diagnosed with an acute PE. The rationale for risk stratification is to identify a particular patient's risk of subsequent hemodynamic deterioration and death. In theory, this information could be used to both define the level of care a patient requires and identify those who may benefit from therapies beyond anticoagulation, such as systemic or catheter-directed thrombolysis or inferior vena cava (IVC) filters. Multiple reports describe the ability of clinical risk scoring systems, biomarkers, and echocardiography to positively and negatively predict the risk of adverse outcomes in individuals with acute PE. While acute PE risk stratification methods have been used to identify high- and low-risk patient populations for inclusion in clinical trials, to our knowledge no study has described the prevalence or impact of risk stratification in routine clinical practice. The purpose of the present study was to determine the frequency of risk stratification over time in patients in a large integrated healthcare system diagnosed as having acute PE and to assess whether risk stratification influenced treatment decisions and outcomes.
