Alternative diagnoses based on CT angiography of the chest in patients with suspected pulmonary thromboembolism.

OBJECTIVE: To determine the prevalence of alternative diagnoses based on chest CT angiography (CTA) in patients with suspected pulmonary thromboembolism (PTE) who tested negative for PTE, as well as whether those alternative diagnoses had been considered prior to the CTA. METHODS: This was a cross-sectional, retrospective study involving 191 adult patients undergoing CTA for suspected PTE between September of 2009 and May of 2012. Chest X-rays and CTAs were reviewed to determine whether the findings suggested an alternative diagnosis in the cases not diagnosed as PTE. Data on symptoms, risk factors, comorbidities, length of hospital stay, and mortality were collected. RESULTS: On the basis of the CTA findings, PTE was diagnosed in 47 cases (24.6%). Among the 144 patients not diagnosed with PTE via CTA, the findings were abnormal in 120 (83.3%). Such findings were consistent with an alternative diagnosis that explained the symptoms in 75 patients (39.3%). Among those 75 cases, there were only 39 (20.4%) in which the same alterations had not been previously detected on chest X-rays. The most common alternative diagnosis, made solely on the basis of the CTA findings, was pneumonia (identified in 20 cases). Symptoms, risk factors, comorbidities, and the in-hospital mortality rate did not differ significantly between the patients with and without PTE. However, the median hospital stay was significantly longer in the patients with PTE than in those without (18.0 and 9.5 days, respectively; p = 0.001). CONCLUSIONS: Our results indicate that chest CTA is useful in cases of suspected PTE, because it can confirm the diagnosis and reveal findings consistent with an alternative diagnosis in a significant number of patients.

Alternative diagnoses based on CT angiography of the chest in patients with suspected pulmonary thromboembolism / Diagnósticos alternativos corroborados por angiotomografia computadorizada de tórax em pacientes com suspeita de tromboembolia pulmonar

Objective : To determine the prevalence of alternative diagnoses based on chest CT angiography (CTA) in patients with suspected pulmonary thromboembolism (PTE) who tested negative for PTE, as well as whether those alternative diagnoses had been considered prior to the CTA. Methods : This was a cross-sectional, retrospective study involving 191 adult patients undergoing CTA for suspected PTE between September of 2009 and May of 2012. Chest X-rays and CTAs were reviewed to determine whether the findings suggested an alternative diagnosis in the cases not diagnosed as PTE. Data on symptoms, risk factors, comorbidities, length of hospital stay, and mortality were collected. Results : On the basis of the CTA findings, PTE was diagnosed in 47 cases (24.6%). Among the 144 patients not diagnosed with PTE via CTA, the findings were abnormal in 120 (83.3%). Such findings were consistent with an alternative diagnosis that explained the symptoms in 75 patients (39.3%). Among those 75 cases, there were only 39 (20.4%) in which the same alterations had not been previously detected on chest X-rays. The most common alternative diagnosis, made solely on the basis of the CTA findings, was pneumonia (identified in 20 cases). Symptoms, risk factors, comorbidities, and the in-hospital mortality rate did not differ significantly between the patients with and without PTE. However, the median hospital stay was significantly longer in the patients with PTE than in those without (18.0 and 9.5 days, respectively; p = 0.001). Conclusions : Our results indicate that chest CTA is useful in cases of suspected PTE, because it can confirm the diagnosis and reveal findings consistent with an alternative diagnosis in a significant number of patients.

Objetivo : Determinar a prevalência de diagnósticos alternativos corroborados por angiotomografia computadorizada (angio-TC) de tórax em pacientes com suspeita de tromboembolia pulmonar (TEP) e com resultados negativos para TEP, assim como investigar se esses diagnósticos alternativos já haviam sido identificados antes dos resultados da angio-TC. Métodos : Estudo transversal, retrospectivo, com 191 pacientes adultos que realizaram angio-TC por suspeita de TEP no período entre setembro de 2009 e maio de 2012. As radiografias de tórax e as angio-TCs foram revisadas para determinar se os achados poderiam fornecer um diagnóstico alternativo nos casos não diagnosticados como TEP. Dados sobre sintomas, fatores de risco, comorbidades, tempo de internação e mortalidade foram coletados. Resultados : A angio-TC foi positiva para tromboembolia pulmonar em 47 casos (24,6%). Entre os 144 pacientes sem tromboembolia pulmonar, achados anormais foram observados em 120 (83,3%). Tais achados foram compatíveis com um diagnóstico alternativo que explicava os sintomas do paciente em 75 casos (39,3%). Desses 75 casos, os achados não haviam sido detectados previamente na radiografia de tórax em apenas 39 (20,4%) dos casos. O diagnóstico alternativo mais frequente, identificado somente por angio-TC, foi pneumonia (em 20 casos). Sintomas, fatores de risco, comorbidades e taxa de óbito intra-hospitalar não diferiram significativamente entre os pacientes com ou sem TEP. Entretanto, a mediana de tempo de internação foi significativamente maior nos pacientes com TEP do que naqueles sem TEP (18,0 e 9,5 dias, respectivamente; p = 0,001). Conclusões : Nossos resultados demonstram que a angio-TC de tórax é útil em casos com suspeita de TEP, pois pode confirmar o diagnóstico e evidenciar achados sugestivos de um diagnóstico alternativo em um significativo número de pacientes.