The detection of pulmonary embolisms after a coronary artery bypass graft surgery by the use of 64-slice multidetector CT

Abstract

The purpose of this study was to examine the incidence of pulmonary embolism (PE) after a coronary artery bypass graft (CABG) using 64-slice multidetector CT (MDCT), and to determine the correlations between the occurrence of a PE and the clinical or surgical parameters. Three hundred and twenty-six consecutive patients, who underwent coronary CT angiography using 64-slice MDCT to assess the graft patency after CABG, were enrolled in this study. Additional axial CT images, which were reconstructed by adopting a large field of view and thinner image slices, were reviewed for the presence of PE. The relationship between the occurrence of a PE and the type of surgery (off-pump CABG versus conventional CABG), number of target vessels, use of a saphenous vein graft, and length of stay in the intensive care unit (ICU) were evaluated. PE was detected on the CT images of 33 patients (10.1%), which involved the lobar or more proximal arteries in seven patients and the segmental or subsegmental arteries in 26. PE occurred more frequently after off-pump CABG (16.5%, 14/85) than after conventional CABG (7.9%, 19/241) (P = 0.024). Patients with PE were older (67 years vs. 62.7 years) and had longer stays in the ICU (5.6 days vs. 3.8 days) than those without (P = 0.013 and P = 0.007, respectively). No significant difference was observed in the number of target vessels and use of a saphenous vein graft between patients with and without an embolism. In a multi-variable analysis, the age of the patient, surgical methods, and ICU stay were independent predictors for the occurrence of PE (P = 0.013, P = 0.017, and P = 0.005, respectively). MDCT helps detect PE in patients after CABG. It is encountered more frequently after off-pump CABG than after conventional CABG and in older patients with longer ICU stays.

The predictive role of computed tomography on respiratory complications following coronary artery bypass surgery

“…These problems may vary from a clinically insignificant mild hypoxemia to acute respiratory distress syndrome [1,4]. The main reason for the hypoxemia seen after surgery is ventilation / perfusion mismatch occurrence due to interruption of ventilation [1,[4][5][6][7]. The use of CPB may also double the risk of postoperative hypoxemia compared to patients without CPB [1,4,6,7].…”

“…The main reason for the hypoxemia seen after surgery is ventilation / perfusion mismatch occurrence due to interruption of ventilation [1,[4][5][6][7]. The use of CPB may also double the risk of postoperative hypoxemia compared to patients without CPB [1,4,6,7]. In a well-designed observational study by Rodrigues and his colleagues on patients with CABG, a 24% increase in collapsed lung tissue, a significant reduction in pulmonary gas volume, an increase in the amount of extravascular pulmonary fluid, and a significant decrease in normally ventilated parenchyma were seen [1].…”

Prevalence and Significance of Clinically Unsuspected Pulmonary Embolism: Detection Using Coronary Computed Tomography Angiography

“…Haller et al reported that the rate of unsuspected PE was 0.6% in coronary CTA, but did not include patients post–cardiac surgery . The results of previous studies on unsuspected PE after coronary artery bypass grafting (CABG suggest a prevalence of 1.9%–10.1% in their respective patient populations . Mueller et al reported that 5/259 (1.9%) patients undergoing coronary CTA after CABG had PE .…”

“…According to a recent meta‐analysis, the prevalence of unsuspected PE detected using contrast‐enhanced CT performed for other reasons is approximately 2.6% . Although clinically unsuspected PE can be detected in patients undergoing coronary CTA, particularly post–cardiac surgery, the prevalence and significance of these unsuspected PE remain unclear …”

Cardiovascular imaging 2011 in the International Journal of Cardiovascular Imaging

“…Sohn et al [87] concluded in their study that knowledge and awareness of MDCT findings relevant to the Ghent nosology give important clues for the diagnosis of Marfan syndrome that provides better patient care. Finally, Lee et al [88] concluded that MSCT helps detecting pulmonary embolism in patients after CABG, and that it is encountered more frequently after off-pump CABG than after conventional CABG and in older patients with longer ICU stay.…”