CT Pulmonary Angiography: Increasingly Diagnosing Less Severe Pulmonary Emboli

Abstract

BackgroundIt is unknown whether the observed increase in computed tomography pulmonary angiography (CTPA) utilization has resulted in increased detection of pulmonary emboli (PEs) with a less severe disease spectrum.MethodsTrends in utilization, diagnostic yield, and disease severity were evaluated for 4,048 consecutive initial CTPAs performed in adult patients in the emergency department of a large urban academic medical center between 1/1/2004 and 10/31/2009. Transthoracic echocardiography (TTE) findings and peak serum troponin levels were evaluated to assess for the presence of PE-associated right ventricular (RV) abnormalities (dysfunction or dilatation) and myocardial injury, respectively. Statistical analyses were performed using multivariate logistic regression.Results268 CTPAs (6.6%) were positive for acute PE, and 3,780 (93.4%) demonstrated either no PE or chronic PE. There was a significant increase in the likelihood of undergoing CTPA per year during the study period (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.04–1.07, P<0.01). There was no significant change in the likelihood of having a CTPA diagnostic of an acute PE per year (OR 1.03, 95% CI 0.95–1.11, P = 0.49). The likelihood of diagnosing a less severe PE on CTPA with no associated RV abnormalities or myocardial injury increased per year during the study period (OR 1.39, 95% CI 1.10–1.75, P = 0.01).ConclusionsCTPA utilization has risen with no corresponding change in diagnostic yield, resulting in an increase in PE detection. There is a concurrent rise in the likelihood of diagnosing a less clinically severe spectrum of PEs.

Software-Based Hybrid Perfusion SPECT/CT Provides Diagnostic Accuracy When Other Pulmonary Embolism Imaging Is Indeterminate

“…Our institutional nondiagnostic CTPA rate is 6.5 % (49/ 759), similar to what has been reported [11]. On the other hand, current techniques may render CTPA as too sensitive, resulting in overdiagnosis and overtreatment of PE, i.e., finding clinically unimportant PE and exposing patients to potential harm from unnecessary treatment [25][26][27]. False negative Q-SPECT/CT cases in our studies echoed this argument, as there was no functional consequences of PE, i.e., perfusion defect, in small nonocclusive subsegmental PE (Fig.…”

Variation in the utilization and positivity rates of CT pulmonary angiography among emergency physicians at a tertiary academic emergency department

“…Clinical guidelines have been developed in recent years to aid in deciding when to use CTPA [6]. However, despite the implementation of such guidelines, both utilization and diagnostic yield rates vary considerably across published data, suggesting likely overuse in some settings and underuse in others [7,8].…”

Pulmonary Hypertension: A Nomogram Based on CT Pulmonary Angiographic Data for Prediction in Patients without Pulmonary Embolism

“…However, PE is actually diagnosed in only 5%-15% of the scanned patients (1)(2)(3). Alternative diagnoses that may explain the patients' symptoms sometimes are identified, with pneumonia being the most frequent among them (4).…”