A novel method to risk stratify patients undergoing exercise stress echocardiography using a set of combined criteria.

Background and Purposes A novel method using quantitative long-axis function and tissue Doppler in addition to wall motion analysis in exercise stress echocardiography was evaluated. We hypothesized that the novel criteria added additional accuracy in stress echocardiography. Methods Patients with chest pain and at low-to-intermediate risk for obstructive coronary artery disease (CAD) were retrospectively studied. They underwent stress echocardiography with attention to wall motion abnormalities, left ventricular long-axis function, and tissue Doppler measurement. Results The results showed that the combined novel criteria (i.e., classifying a case as positive if three out of the following four criteria were fulfilled: (1) abnormal segmental wall motion shortly after peak stress; (2) Ee wave after peak stress less than 10 cm/s and Ee/Aa ratio after peak stress less than 1; (3) Sm wave after peak stress less than 10.5 cm/s; (4) abnormal long-axis left ventricular function) offered a better accuracy for predicting obstructive CAD and future revascularization with a high sensitivity (100%) and high negative predictive value (100%) . Conclusion From a practical standpoint, the combined novel criteria may be useful in improving the diagnostic accuracy of stress echocardiography.

A novel method to quantify carotid artery stenosis by Doppler ultrasound: Using the continuity principle.

BACKGROUND AND PURPOSE: A novel method to quantify carotid artery stenosis by using the continuity principle was evaluated. It was hypothesized that the novel method improved the accuracy of carotid ultrasound in assessing carotid artery stenosis. METHODS: Forty-nine patients were retrospectively studied. They were at a high risk for stroke and myocardial infarction, with significant cardiovascular risk factors. They were studied by carotid ultrasound as well as by one of the accepted gold standard techniques (computed tomography, magnetic resonance imaging or angiography). The cross-sectional areas of the narrowed part of the carotid arteries were measured using the continuity principle, and the percentage stenosis was thus calculated. RESULTS: The analyses showed that the combination of the conventional and novel criteria (ie, classifying a case as significant only if its stenosis was 67% or greater and its peak systolic velocity was 130 cm/s or greater) conferred the highest accuracy in predicting significant carotid stenosis compared with the gold standard techniques. CONCLUSION: From a practical point of view, the combined criteria might be useful for improving the accuracy of carotid ultrasound in predicting significant carotid stenosis.

Diagnostic accuracy of 64 multidetector computed tomographic angiography in peripheral vascular disease.

BACKGROUND: Previous studies of multidetector CT (MDCT) of the lower extremities for the detection of peripheral vascular disease showed high diagnostic accuracy but were performed with older generation systems. OBJECTIVE: The purpose of this study was to evaluate the diagnostic accuracy of 64 MDCT for the detection of hemodynamically significant disease within the lower extremity peripheral vasculature as compared to digital subtraction angiography (DSA). METHODS: Twenty-eight consecutive patients with symptomatic lower extremity intermittent claudication and an abnormal ankle-brachial index (ABI; less than 0.9) were evaluated by both 64 MDCT and DSA. Axial images were acquired with a 64 multidetector general electric light speed VCT scanner. Images were analyzed using a GE Advantage workstation (AW 4.3) capable of advanced image processing and manipulation. The aorto-iliac and lower extremity arteries were divided into 15 segments per limb (30 segments per patient). Eight hundred forty segments were analyzed in a blinded fashion by physicians with level III CT certification. Segments were classified as grade I (<10% stenosis), grade II (10-49%), grade III (50-99%), and grade IV (occlusion). RESULTS: For all segments evaluated, the overall diagnostic accuracy for detecting grade III and IV lesions was 98% with a sensitivity of 99% and a specificity of 98%. For the aorto-iliac segments, the diagnostic accuracy was 98% with a sensitivity of 100% and a specificity of 99%. For the femoro-popliteal segments, the overall accuracy was 98% with a sensitivity of 100% and a specificity of 99%. For the infra-popliteal segments, the overall accuracy was 98% with a sensitivity of 97% and a specificity of 99%. One segment could not be visualized by MDCT compared to 49 segments that could not be visualized by DSA. CONCLUSIONS: This study demonstrates excellent diagnostic accuracy of 64 MDCT in the detection of hemodynamically significant disease of the lower extremities. More segments are visualized using 64 MDCT than DSA, allowing more complete visualization of the vascular tree. CT angiography should be considered in the diagnostic evaluation of symptomatic patients with peripheral vascular disease.

A novel method of coronary stent sizing using intravascular ultrasound: Safety and clinical outcomes.

OBJECTIVES: The use of intravascular ultrasound (IVUS) in guiding coronary stenting has increased in recent years. The feasibility, safety and clinical outcomes of a novel method of sizing coronary stents using IVUS have not been established. The main end points of the current study are the incidence of acute and short-term complications, and the need for target vessel revascularization at six months. METHODS: Eighty-six patients underwent coronary stenting using IVUS imaging during the procedure. The optimal size of the stents was determined by using a novel method (the 'aggressive IVUS method'), ie, measuring the media-to-media dimensions of the coronary vessels at the site of the lesions using IVUS. A six-month follow-up chart review was performed following the initial stenting. RESULTS: At six months, there were two noncardiac deaths in the group. There were no acute, subacute or late stent thromboses. Target vessel revascularization and major adverse cardiac event rates remained low - at 5.8% and 9.3%, respectively. The mean (± SD) IVUS-derived coronary stent size (3.89±0.98 mm) using the aggressive IVUS method was significantly different from the mean IVUS-derived coronary stent size (3.46±0.96 mm) using the 'traditional IVUS method'. CONCLUSION: Aggressive sizing of the coronary stents by IVUS guidance is feasible and safe, and is associated with a favourable clinical outcome.