			Home About us Contact

Stenotic Segment (stenotic + segment)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Role of a Streamer-like Coronary Thrombus in the Genesis of Unstable Angina

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2010
YASUMI UCHIDA M.D.
Introduction: It is generally believed that the coronary occlusion occurs at the site of plaque disruption in acute coronary syndromes. An exceptional mechanism of coronary occlusion, namely a streamer-like thrombus (SLT) originating in a nonstenotic lesion extended distally to obstruct a just distal nondisrupted stenotic segment, was found by angioscopy in patients with unstable angina (UA). This study was carried out to examine the incidence of this phenomenon and its relationship to the subtypes of UA. Methods: The culprit coronary artery was investigated by angioscopy in successive 48 patients (mean ± SE age, 61.0 ± 2.3 years; 10 females and 38 males) with UA. Results: SLT originating in a nonstenotic lesion extended distally, and obstructed the just distal most stenotic segment (DMSS) by its tail in 11 patients (eight with class III and three with class II according to Braunwald's classification). Recurrent anginal attacks were observed in all. The nonstenotic lesion in which the SLT originated was a disrupted yellow plaque in most cases. The SLT was frequently red and yellow in a mosaic pattern, indicating a mixture of fresh thrombus and plaque debris. The plaques that constructed the DMSS were not disrupted. Angiographically, the SLT was not detectable and the entry of the DMSS showed a "tapering" configuration. Conclusions: Obstruction of the DMSS by the tail of SLT originating in a nonstenotic lesion is another mechanism of UA. Therefore, treatment of both the nonstenotic lesion and DMSS is needed to prevent recurrent thrombus formation and consequent reattacks. (J Interven Cardiol 2010;23:216,222) [source]

Comparison of Transcranial Color-Coded Sonography and Magnetic Resonance Angiography in Acute Ischemic Stroke

JOURNAL OF NEUROIMAGING, Issue 4 2001
Li-Ming Lien MD
ABSTRACT Background and Purpose. This study was designed to assess the accuracy of transcranial color-coded sonography (TCCS) as compared to magnetic resonance angiography (MRA) for detecting intracranial arterial stenosis in patients with acute cerebral ischemia. Methods. The authors prospectively identified 120 consecutive patients admitted with acute ischemic stroke and performed both TCCS and MRA with a mean interval of 1 day. TCCS data (sampling depth, peak systolic and end diastolic angle-corrected velocity, mean angle-corrected velocity, and pulsatility index) for middle cerebral arteries (MCAs) were compared to MRA data and classified into 4 grades: normal (grade 1): normal caliber and signal; mild stenosis (grade 2): irregular lumen with reduced signal; severe stenosis (grade 3): absent signal in the stenotic segment (flow gap) and reconstituted distal signal; and possible occlusion (grade 4): absent signal. The cutoffs were chosen to maximize diagnostic accuracy. Results. Interobserver agreement for MRA grading resulted in a weighted-kappa value of 0.776. The rate of poor temporal window was 37% (89/240). Doppler signals were obtained in 135 vessels, and the angle-corrected velocities (peak systolic, end diastolic, mean) were significantly different (P= .001, P= .006, P < .001) among the MRA grades: grade 1 (100, 47, 68 cm/s), grade 2 (171, 72, 110 cm/s), grade 3 (226, 79, 134 cm/s), grade 4 (61, 26, 39 cm/s). Additionally, an angle-corrected MCA peak systolic velocity ,120 cm/s correlates with intracranial stenosis on MRA (grade 2 or worse) with high specificity (90.5%; 95% confidence interval = 78.5%,96.8%) and positive predictive value (93.9%) but relatively low sensitivity (66.7%; 95% confidence interval = 61.2%,69.5%) and negative predictive value (55.1%). Conclusion. Elevated MCA velocities on TCCS correlate with intracranial stenosis detected on MRA. An angle-corrected peak systolic velocity ,120 cm/s is highly specific for detecting intracranial stenosis as defined by significant MRA abnormality. [source]

Stent implantation as a stabilization technique in supracardiac total anomalous pulmonary venous connection

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2006
Adrienne Kilgore MD
Abstract A 6-week-old male presented in-extremis with obstructed supra-cardiac total anomalous pulmonary venous connection. Balloon dilation and stent implantation in the stenotic segment of the vertical vein relieved the obstruction until the patient was stable enough to undergo surgical repair. An unusual form of extrinsic vertical vein compression was found at surgery. © 2006 Wiley-Liss, Inc. [source]

Paediatric airway stenosis: laryngotracheal reconstruction or cricotracheal resection?

CLINICAL OTOLARYNGOLOGY, Issue 5 2000
B.E.J. Hartley
Modern surgical management of paediatric laryngotracheal stenosis includes a wide variety of surgical procedures. These can broadly be divided into two groups. First, laryngotracheal reconstruction (LTR) procedures in which the cricoid cartilage is split and the framework is expanded with various combinations of cartilage grafts and stents; and second, cricotracheal resection (CTR) where a segmental excision of the stenotic segment is done and an end-to-end anastomosis is performed. In this article we review the literature and our experience and discuss the relative indications for CTR and LTR in children. High decannulation rates have been reported for CTR; however, it remains a more extensive procedure than LTR involving extensive tracheal mobilization. If the tracheostomy site is included in the resection then a significant length of trachea is excised. Alternatively, LTR with cartilage grafting can precisely correct a specific stenosis with minimum morbidity and high decannulation rates for grade 2 and selected grade 3 stenosis. For the more severe stenosis treatment with LTR has been less successful. Retrospective data from this institution suggests that the children with grade 4 stenosis treated with LTR are more likely to require a subsequent open procedure to achieve decannulation than those treated with CTR. LTR is a less extensive procedure and is preferred for grade 2, selected grade 3 stenosis. CTR is the preferred option for grade 4 and severe grade 3 stenosis with a clear margin between the stenosis and the vocal cords. [source]