Identification of chronic thromboembolic pulmonary hypertension on CTPAs performed for diagnosing acute pulmonary embolism depending on level of expertise

Background: Expert reading often reveals radiological signs of chronic thromboembolic pulmonary hypertension (CTEPH) or chronic PE on computed tomography pulmonary angiography (CTPA) performed at the time of acute pulmonary embolism (PE) presentation preceding CTEPH. Little is known about the accuracy and reproducibility of CTPA reading by radiologists in training in this setting. Objectives: To evaluate 1) whether signs of CTEPH or chronic PE are routinely reported on CTPA for suspected PE; and 2) whether CTEPH-non-expert readers achieve comparable predictive accuracy to CTEPH-expert radiologists after dedicated instruction. Methods: Original reports of CTPAs demonstrating acute PE in 50 patients whom ultimately developed CTEPH, and those of 50 PE who did not, were screened for documented signs of CTEPH. All scans were re-assessed by three CTEPH-expert readers and two CTEPH-non-expert readers (blinded and independently) for predefined signs and overall presence of CTEPH. Results: Signs of chronic PE were mentioned in the original reports of 14/50 cases (28%), while CTEPH-expert radiologists had recognized 44/50 (88%). Using a standardized definition (>= 3 predefined radiological signs), moderate-to-good agreement was reached between CTEPH-non-expert readers and the experts' consensus (kstatistics 0.46; 0.61) at slightly lower sensitivities. The CTEPH-non-expert readers had moderate agreement on the presence of CTEPH (Kappa-statistic 0.38), but both correctly identified most cases (80% and 88%, respectively). Conclusions: Concomitant signs of CTEPH were poorly documented in daily practice, while most CTEPH patients were identified by CTEPH-non-expert readers after dedicated instruction. These findings underline the feasibility of achieving earlier CTEPH diagnosis by assessing CTPAs more attentively.Cardiovascular Aspects of Radiolog

To report or not to report… prognostically relevant incidental chest CT findings

Through the constantly increasing imaging quality and utilization of chest computed tomography (CT) are radiologists routinely confronted with incidental findings reflecting potential (preclinical) manifestations of cardiovascular disease (CVD), chronic obstructive pulmonary disease (COPD) and osteoporosis. However, the exact prognostic value of these incidental imaging findings and whether reporting of these findings will finally lead to patient benefit is not clear yet. This initiated the start of the PROgnostic Value of unrequested Information in Diagnostic Imaging (PROVIDI) study. PROVIDI is a retrospective multicenter cohort study comprising 23 443 subjects, aged ≥ 40 years who underwent routine clinical chest CT scanning between 2002 and 2005 for various diagnostic indications. We investigated whether certain incidental findings detected on diagnostic chest CTs contribute to the prediction of CVD and COPD. Incidental coronary artery calcifications, thoracic aorta calcifications, cardiac valve calcifications as well as cardiovascular diameter measurements were all significantly and independently related to future CVD events. Additionally, a simple CVD event risk score incorporating this information on cardiovascular features embedded in diagnostic chest CT, was developed and validated. This risk score was conceived from the perspective of the radiologists enabling accurate stratification of individuals into clinically relevant risk categories used in current CVD guidelines. Besides age and gender no other conventional risk factors were included in the risk score, since in general these patient characteristics are not available to the radiologist. Nevertheless, we would like to stress that extensive literature has clearly documented the uncertainty of risk scores based on conventional risk factors, because conventional risk factors are mere a surrogate for atherosclerosis. The CT based risk score as presented in this thesis is based on direct measures of atherosclerosis, providing a novel strategy and adequate estimation of CVD risk irrespective of the conventional risk factor status. Furthermore, morphologic correlates of COPD, such as emphysema and airway thickening, detected on CT scans obtained for other indications, demonstrated to be related to future hospitalization or death due to acute exacerbations of COPD. As for many people, however, information on these prognostically valuable metrics of CVD and COPD are 'freely' available since chest CT has developed into a very common imaging modality in the evaluation of (suspected) thoracic disease. With over 350.000 chest CTs performed annually in the Netherlands, diagnostic clinical CT scans offer a great opportunity to detect individuals at high-risk for CVD and COPD at an early stage, and hence better target these subjects for more tailored treatments based on incidental information embedded in routine diagnostic chest CTs in a clinical care population. This type of 'collateral information' obtained by chest CT can stimulate the start of prevention measures in subjects not recognized as high-risk by current risk algorithms. However, to state with confidence that utilization of incidental cardiovascular CT findings is cost-effective and effectuates improve in CVD outcome, a prospective randomized multicenter trial should be performed