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The purpose of this study was to assess the diagnostic performance of stress perfusion dual-energy CT (DECT) and its incremental value when used with coronary CT angiography (CTA) for identifying hemodynamically significant coronary artery disease.One hundred patients with suspected or known coronary artery disease without chronic myocardial infarction detected with coronary CTA underwent stress perfusion DECT, stress cardiovascular perfusion MRI, and invasive coronary angiography (ICA). Stress perfusion DECT and cardiovascular stress perfusion MR images were used for detecting perfusion defects. Coronary CTA and ICA were evaluated in the detection of ≥50% coronary stenosis. The diagnostic performance of coronary CTA for detecting hemo-dynamically significant stenosis was assessed before and after stress perfusion DECT on a per-vessel basis with ICA and cardiovascular stress perfusion MRI as the reference standard.The performance of stress perfusion DECT compared with cardiovascular stress perfusion MRI on a per-vessel basis in the detection of perfusion defects was sensitivity, 89%; specificity, 74%; positive predictive value, 73%; negative predictive value, 90%. Per segment, these values were sensitivity, 76%; specificity, 80%; positive predictive value, 63%; and negative predictive value, 88%. Compared with ICA and cardiovascular stress perfusion MRI per vessel territory the sensitivity, specificity, positive predictive value, and negative predictive value of coronary CTA were 95%, 61%, 61%, and 95%. The values for stress perfusion DECT were 92%, 72%, 68%, and 94%. The values for coronary CTA and stress perfusion DECT were 88%, 79%, 73%, and 91%. The ROC AUC increased from 0.78 to 0.84 (p=0.02) with the use of coronary CTA and stress perfusion DECT compared with coronary CTA alone.Stress perfusion DECT plays a complementary role in enhancing the accuracy of coronary CTA for identifying hemodynamically significant coronary stenosis.

There is growing evidence supporting the use of coronary CT angiography (CTA) to triage patients in the emergency department (ED) with acute chest pain and low risk of acute coronary syndrome (ACS). We hypothesized that coronary CTA can guide early management and safely discharge patients by introducing a dedicated patient management protocol.We conducted a prospective cohort study in three EDs of a large health care system (1300 beds). Five hundred twenty-nine patients (mean age, 52.1 years; 56% women) with chest pain, negative cardiac enzyme results, normal or nondiagnostic ECG findings, and a thrombolysis in myocardial infarction (TIMI) risk score of 2 or less were admitted and underwent CTA. A new dedicated chest pain triage protocol (levels 1-5) was implemented. On the basis of CTA findings, patients were stratified into one of the following four groups: 0, low (negative CTA findings); 1, mild (1-49% stenosis); 2, moderate (50-69% stenosis); or 3, severe (≥ 70% stenosis) risk of ACS. Outcome measures included major adverse cardiac events (MACEs) during the first 30 days after CTA, downstream testing results, and length of stay (LOS). LOS was compared before and after implementation of our chest pain triage protocol.Three hundred seventeen patients (59.9%) with negative CTA findings and 151 (28.5%) with mild stenosis were discharged from the ED with a very low downstream testing rate and a very low MACE rate (negative predictive value = 99.8%). Twenty-five patients (4.7%) had moderate stenosis (n = 17 undergoing further testing). Thirty-six patients (6.8%) had stenosis of 70% or greater by CTA (n = 34 positive by invasive angiography or SPECT-myocardial perfusion imaging). The sensitivity of CTA was 94%. The rate of MACEs in patients with stenosis of 70% or greater (8.3%) was significantly higher (p0.001) than in patients with negative CTA findings (0%) or those with mild stenosis (0.2%). A 51% decrease in LOS-from 28.8 to 14.0 hours--was noted after implementation of the dedicated chest pain protocol (p0.001).Chest pain patients with negative or mild nonobstructive CTA findings can be safely discharged from the ED without further testing. Implementation of a dedicated chest pain triage protocol is critical for the success of a coronary CTA program.

The purpose of this study is to evaluate the diagnostic performance of CT, compared with that of echocardiography and surgery, for differentiating between bicuspid and tricuspid aortic valves.Forty-seven patients with bicuspid valve and 47 patients with tricuspid aortic valve underwent retrospectively ECG-gated dual-source CT and echocardiography. Thirty-four (72%) of the 47 patients with bicuspid aortic valve underwent valve surgery. Two independent blinded observers assessed the CT image quality of the aortic valve during diastole and systole on a 4-point scale, determined which phase allowed the differentiation of valve type, distinguished between tricuspid and bicuspid aortic valves, and assessed for the presence of a raphe. Diagnostic performance of CT was determined using echocardiography and surgery as the reference standard.According to echocardiography and surgery, seven (15%) of the 47 bicuspid aortic valves had no raphe, and 40 (85%) had a raphe. CT image quality was diagnostic (i.e., scores of 1-3) in all 94 patients in both diastole and systole. Among patients with bicuspid aortic valve and no raphe, differentiation between tricuspid and bicuspid aortic valves could be performed in diastole in 100% (7/7) of cases. Among patients with bicuspid aortic valve and raphe, differentiation was possible only in systole in 5% (2/40) of cases and when combining diastole and systole in 95% (38/40) of cases. In three bicuspid aortic valves with raphe, the valve was misclassified by CT as tricuspid aortic valve. Overall sensitivity and specificity of CT for the diagnosis of bicuspid aortic valve were 94% and 100%.CT is highly accurate for differentiation between bicuspid and tricuspid aortic valves. For bicuspid aortic valves without raphe, diastolic reconstructions are sufficient, whereas in those with a raphe, additional reconstructions in systole are required.

Real-time sonoelastography is a new ultrasound-based technique able to assess tissue elasticity that has already shown feasibility in tumor diagnosis. The aim of this study was to assess the performance of real-time sonoelastography in depicting the Achilles tendons of healthy volunteers and to compare sonoelastography findings with conventional ultrasound findings.Eighty asymptomatic Achilles tendons of 40 healthy volunteers (19 men, 21 women; mean age, 38 years; range, 20-76 years) were examined on real-time sonoelastography and ultrasound. The Achilles tendons were divided into the following thirds for image evaluation: proximal (musculotendinous junction), middle (2-6 cm above insertion at the calcaneus), and distal (insertion at the calcaneus). Longitudinal and axial images of each tendon third were obtained using ultrasound and real-time sonoelastography. Real-time sonoelastography images were evaluated by reviewers using an experimentally proven color grading system.The Achilles tendons showed mainly a hard structured pattern (86.7%) (208/240 tendon thirds) on sonoelastography; however, mild softening was found in 12.1% (29/240) of the tendons. Distinct softening corresponding to alterations found also on ultrasound and, therefore, suggesting subclinical changes was detected in 1.3% (3/240). The overall correlation (kappa) between real-time sonoelastography and ultrasound findings was 1.00.In healthy volunteers, the Achilles tendon appeared hard on real-time sonoelastography with excellent correlation to ultrasound. Further investigation including pathologic tendons should be performed to prove the value of real-time sonoelastography in the assessment of Achilles tendinopathy.

The purpose of this study was to compare the diagnostic accuracy of 64-slice CT with that of invasive angiography in the detection of greater than 50% graft stenosis within 2 weeks of coronary artery bypass grafting and to investigate the clinical value of 64-slice CT.Forty-one patients (70 grafts, 46 arterial and 24 venous) underwent 64-slice CT a mean of 2.6 years after minimally invasive or conventional coronary artery bypass surgery.All 70 grafts were assessable, and none of the grafts was excluded from analysis. For the detection of 50-90% graft stenosis, the sensitivity of CT was 75%, the specificity was 95%, the positive predictive value was 67%, and the negative predictive value was 97% (true disease prevalence, 8/70 grafts; 11%). Greater than 50% graft stenosis and occlusion pooled together (prevalence, 14/70; 20%) were detected with a sensitivity of 85%, specificity of 95%, positive predictive value of 80%, and negative predictive value of 96%. Vein graft disease was found in eight (42%) of 19 patent vein grafts (graft age, 15.6 +/- 2.3 years). The disease was nonobstructive in three (16%) of the 19 grafts. The course of the left internal mammary artery was median retrosternal (1 cm deep) in 33.3% of conventionally sutured grafts.Sixty-four-slice CT angiography can be used for accurate exclusion of greater than 50% graft stenosis, but detection of distal anastomotic stenosis is limited, and the degree of stenosis can be overestimated. The advantages of CT, however, are that it is noninvasive, vein graft disease can be diagnosed at an early stage, and complementary evaluation of extracardiac anatomic features provides useful information before coronary artery bypass grafting is redone.

OBJECTIVE. The objective of our study was to assess the feasibility of using 16-MDCT angiography for the preoperative assessment of the radial and ulnar arteries and the palmar arches in patients scheduled for radial artery harvesting for coronary artery bypass graft (CABG) surgery.CONCLUSION. Sixteen-MDCT angiography shows promise for the noninvasive preoperative assessment of the radial artery as a CABG donor site.