Florian Teige

Coronary artery stenosis quantification using multislice computed tomography.

Rationale and Objectives:Reliable noninvasive detection of stenoses with multislice computed tomography (MSCT) is feasible. This studys aim was to analyze the agreement, correlation, and reliability of MSCT with conventional coronary angiography as the reference standard for quantification of coronary artery stenoses. Materials and Methods:A total of 118 significant (at least 50%) coronary artery stenoses with a reference vessel diameter of at least 1.5 mm in 62 patients were analyzed by MSCT using 16 detector rows (Aquilion, Toshiba, Otawara, Japan), multisegment reconstruction, and voxel sizes of 0.35 × 0.35 × 0.5 mm3. The degree of stenosis on MSCT and quantitative coronary angiography (QCA) was measured by correlating the difference between the reference vessel diameter (average of 2 measurements directly proximal and distal to the stenosis) and the stenotic vessel diameter to the reference vessel diameter. Results:Correlation between the percent diameter stenosis determined by MSCT (78.2 ± 13.6%) and QCA (76.0 ± 14.8%) was significant (P < 0.001) but only moderately so (R = 0.51). Bland-Altman analysis revealed no systematic under- or overestimation with MSCT but large limits of agreements (±27.6%). Also the limits of agreement for interobserver agreement (reliability) of MSCT data were considerably large (±24.8%). Among the 27 coronary artery stenoses with a reference diameter of at least 3.5 mm, there was improved correlation (R = 0.80) and the limits of agreement between MSCT and QCA were significantly smaller (±17.3%, P < 0.008). The agreement between MSCT and QCA was not significantly different for stenoses with no calcification or only calcium spots (±28.2%) as compared with those with moderate-or-severe calcifications (±27.3%; P = 0.8). MSCT allowed correct classification of coronary stenoses into low-grade (below 75%) and high-grade stenoses (at least 75%), in 62% (73 of 118). Conclusions:The accuracy and reliability of coronary artery stenosis quantification with MSCT using isotropic voxel sizes and multisegment reconstruction is still too low to recommend routine clinical application because of rather low agreement, correlation, and reliability. Despite these limitations, the current results demonstrate the potential of MSCT for reliable and accurate quantification of coronary artery stenoses in the near future provided that further improvements in spatial and temporal resolution will be achieved.

Combination of free-breathing and breathhold steady-state free precession magnetic resonance angiography for detection of coronary artery stenoses

To analyze the incremental diagnostic value of a combination of two approaches (free‐breathing and breathhold) vs. the sole free‐breathing approach to coronary magnetic resonance angiography (CMRA) for detection of significant stenoses.

Multisegment and halfscan reconstruction of 16-slice computed tomography for assessment of regional and global left ventricular myocardial function.

Rationale and Objectives:We sought to prospectively compare multisegment and halfscan reconstruction of 16-slice computed tomography (CT) for the assessment of regional and global left ventricular myocardial function with magnetic resonance imaging (MRI) as the reference standard. Materials and Methods:Forty-two patients underwent CT with 16 × 0.5-mm detector collimation. Electrocardiogram-gated reconstructions were generated with multisegment reconstruction (using up to 4 segments correlated with the raw data of up to 4 heartbeats) and standard halfscan reconstruction. Steady-state free-precession cine MRI was acquired within 24 hours. Results:More normal myocardial segments were identified correctly with multisegment (95%, 620/656) compared with halfscan reconstruction (88%, 582/656) of CT (P < 0.001). Also, the accuracy (92% [657/714] vs. 87% [620/714]) and rate of nondiagnostic segments (0% vs. 5% [33/714]) were significantly better when using multisegment reconstruction (P < 0.001). The image quality with multisegment reconstruction was significantly superior to that achieved with halfscan reconstruction (P < 0.001). In the assessment of global left ventricular function, multisegment and halfscan reconstruction of CT showed high correlations for all parameters with MRI, whereas Bland-Altman analysis revealed smaller limits of agreement for assessment of myocardial mass with multisegment reconstruction (P = 0.025), but no significant differences between both reconstruction techniques in the measurement of left ventricular volumes as compared with MRI. Conclusions:Multisegment reconstruction of 16-detector row CT improves image quality and assessment of regional wall motion compared with standard halfscan reconstruction.

Patient Acceptance of Noninvasive and Invasive Coronary Angiography

Background Noninvasive angiography using multislice computed tomography (MSCT) is superior to magnetic resonance imaging (MRI) for detection of coronary stenoses. We compared patient acceptance of these two noninvasive diagnostic tests and invasive conventional coronary angiography (Angio). Methods and Findings A total of 111 consecutive patients with suspected coronary artery disease underwent MSCT, MRI, and Angio. Subsequently, patient acceptance of the three tests was evaluated with questionnaires in all patients. The main acceptance variables were preparation and information prior to the test, degree of concern, comfort, degree of helplessness, pain (on visual analog scales), willingness to undergo the test again, and overall satisfaction. Preparation for each test was not rated significantly differently, whereas patients were significantly more concerned about Angio than the two noninvasive tests (p<0.001). No pain during MSCT, MRI, and Angio as assessed on visual analog scales (0 to 100) was reported by 99, 93, and 31 patients, respectively. Among the 82 patients who felt pain during at least one procedure, both CT (0.9±4.5) and MRI (5.2±16.6) were significantly less painful than Angio (24.6±23.4, both p<0.001). MSCT was considered significantly more comfortable (1.49±0.64) than MRI (1.75±0.81, p<0.001). In both the no-revascularization (55 patients) and the revascularization group (56 patients), the majority of the patients (73 and 71%) would prefer MSCT to MRI and Angio for future imaging of the coronary arteries. None of the patients indicated to be unwilling to undergo MSCT again. The major advantages patients attributed to MSCT were its fast, uncomplicated, noninvasive, and painless nature. Conclusions Noninvasive coronary angiography with MSCT is considered more comfortable than MRI and both MSCT and MRI are less painful than Angio. Patient preference for MSCT might tip the scales in favor of this test provided that the diagnostic accuracy of MSCT can be shown to be high enough for clinical application.