Israel Medical Association Journal

Background: Cardiac computed tomography angiography is a relatively new imaging modality to detect coronary atherosclerosis.

Objectives: To explore the diagnostic value of CTA[1] in assessing coronary artery disease among asymptomatic patients.

Methods: In this retrospective single-centered analysis, 622 consecutive patients underwent CTA of coronary arteries between November 2004 and May 2006 at the Mor Institute for Cardiovascular Imaging in Bnei Brak, Israel. All patients were asymptomatic but had at least one risk factor for atherosclerotic CAD[2]. The initial 244 patients were examined with the 16-slice Brilliance CT scanner (Philips, Cleveland, OH, USA), and in the remaining 378 patients the 64-slice scanner (GE Healthcare, The Netherlands) with dedicated cardiac reconstruction software and electrocardiography triggering was used. Scanning was performed in the cranio-caudal direction. Images reconstructed in different phases of the cardiac cycle using a retrospective ECG-gated reconstruction algorithm were transferred to a dedicated workstation for review by experienced CT radiologists and cardiologists.

Results: Of 622 patients, 52 (8.4%) had severe obstructive atherosclerosis (suspected ≥ 75% stenosis) according to CTA interpretation. Invasive coronary angiography was performed in 48 patients while 4 patients had no further procedure. A non-significant CAD (e.g., diameter stenosis < 70%) was identified in 6 of 48 patients (12%) by selective coronary angiography. Forty-two patients showed severe CAD with at least one lesion of ≥ 70% stenosis. Percutaneous coronary intervention was performed in 35 patients and coronary artery bypass grafting surgery in the other 4 patients. Angioplasty procedures were successful in all 35 patients and stents were utilized in all cases without complications. No further complications occurred among the study cohort undergoing either PCI[3] or surgery. The 6 month survival rate in these patients was 100%.

Conclusions: Non-invasive coronary CTA appears to be a reliable technique, with reasonably high accuracy, to detect obstructive atherosclerosis in asymptomatic high risk patients for atherosclerotic CAD.

Background: Diseases causing increased pulmonary pressure will subsequently cause a dilation of the pulmonary arteries and right heart chambers.

Objectives: To assess the capability of computed tomography angiography and high resolution CT to diagnose and estimate the severity of pulmonary arterial hypertension as compared with standard means of right heart catheterization, echocardiography and pulmonary function tests.

Methods: The study included 38 patients with PHT[1] who underwent CT angiography and HRCT[2] as part of their routine evaluation. Diagnose included: primary PHT (n=20), Eisenmenger syndrome (n=6), scleroderma (n=3), thromboembolic disease (n=3), and others (n=6). Mean pulmonary artery pressure was 58 mmHg (range 39–92 mmHg) by catheterization and peak systolic pressure 79 mmHg (range 40–135) by echocardiography. Findings for the diameters of the main pulmonary artery and its main branches, the ascending aorta, the right atria and ventricle as well as the position of the interventricular septum were compared with 22 chest CT scans as compared to patients with no known clinical history of pulmonary hypertension, performed for other reasons (trauma, oncology follow-up) during the study period. Correlations were also calculated with recent right heart catheterization, echocardiography and pulmonary function tests of the study group.

Results: Mean main pulmonary artery diameter in the study group was 3.55 ± 0.66 cm, pulmonary artery/ascending aorta ratio 1.2 ± 0.29, right pulmonary artery 2.63 ± 0.49 cm, left pulmonary artery 2.57 ± 0.5 cm. All diameters were significantly different from the control group (P < 0.0001). Main and right pulmonary artery diameters correlated to the pressure measurement by echocardiography (P = 0.001). Bronchial collaterals were found in 11 patients (30%). The position of the interventricular septum correlated well with the echocardiography study.

Conclusions: The size of the main pulmonary artery on CT angiography has a good predictive value regarding the severity of PHT.

Background: Femoral artery vascular complications are the most common adverse events following cardiac catheterization. Smaller diameter introducer sheaths and catheters are likely to lower the puncture site complication rate but may hinder visualization.

Objectives: To evaluate the safety and angiographic quality of 4 French catheters.

Methods: The study was designed to simulate real-life operator-based experience. Diagnostic angiography was performed with either 4F or 6F diagnostic catheters; the size of the catheter used in each patient was predetermined by the day of the month. Patients undergoing 4F and 6F diagnostic angiography were ambulated after 4 and 6 hours, respectively. The following technical parameters were recorded by the operator: ease of introducer sheath insertion, ease of coronary intubation, ease of injection, coronary opacification, collateral flow demonstration, and overall assessment. Adverse events were recorded in all patients and included minor bleeding, major bleeding (necessitating blood transfusion), minor hematoma, major hematoma, pseudo-aneurysm formation and arteriovenous fistula.

Results: The study group included 177 patients, of whom 91 were in the 4F arm and 86 in the 6F arm. Demographic and procedural data were similar in both groups. Seventy-seven percent of 6F and 50% of 4F procedures were evaluated as excellent (P < 0.05). This difference was attributed to easier intubation of the coronary ostium and contrast material injection, increased opacification of the coronary arteries, and demonstration of collateral flow with 6F catheters. Complications occurred in 22% of patients treated with 6F catheters and 10% of those treated with 4F catheters (P = 0.11). Of the 50 patients who switched from 4F to 6F 12% had complications. In patients undergoing diagnostic angiography, the complication rate was 10% vs. 27% (most of them minor) in the 4F and 6F groups, respectively (P < 0.05).
Conclusions: Patients catheterized with 4F have fewer complications compared with 6F diagnostic catheters even when ambulated earlier. Although 4F had a reduced quality compared to 6F angiographies, they were evaluated as satisfactory or excellent in quality 85% of the time. 4F catheters have a potential for reduced hospitalization stay and are a good option for primary catheterization in patients not anticipated to undergo coronary intervention

Multidetector-row computed tomography has been validated as a useful non-invasive diagnostic method in patients with various cardiac diseases.

Objectives: To evaluate the accuracy of 16-slice multi-detector CT angiography in the diagnosis of coronary artery disease, and assess coronary bypass grafts and coronary anomalies.

Methods: We conducted a retrospective study of 223 patients who were examined at our medical center over a period of 2 years with a 16-slice CT angiography scanner and retrospective electrocardiographic gating.

Results: There were no significant complications, and good visualization of the coronary arteries was achieved in all but eight patients. A high correlation with the results of the invasive angiography was noted (sensitivity 85%, specificity 93%, negative predictive value 98%). Altogether, 131 bypass conduits were examined with excellent graft visualization. Several coronary anomalies were detected, as were significant extra-cardiac findings.

Conclusions: Multi-slice CT angiography is a reliable non-invasive diagnostic procedure for demonstration of the coronary arteries and bypass grafts. In the future it will probably replace part of the diagnostic invasive coronary angiography and, as a result, a large proportion of coronary angiography procedures will be therapeutic.

Gadolinium-based agents are widely used in magnetic resonance imaging as contrast agents. These agents are radio-opaque enough for diagnostic imaging of the vascular tree by using digitally subtracted images as well as for imaging of the biliary system and the urinary tract. The recommended doses for gadolinium do not impair renal function or cause adverse reactions in patients with iodine sensitivity; thus patients with such conditions can safely undergo diagnostic angiography, either by MRI angiography or by catheterization using gadolinium as contrast agent, for diagnostic and therapeutic purposes.