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LAD Stenosis (lad + stenosis)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Transthoracic Doppler Echocardiographic Coronary Flow Imaging in Identification of Left Anterior Descending Coronary Artery Stenosis in Patients with Left Bundle Branch Block

ECHOCARDIOGRAPHY, Issue 10 2008
Ozer Soylu M.D.
Background: Conventional noninvasive methods have well-known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic value of transthoracic CFR measurements for detection of significant left anterior descending (LAD) stenosis in patients with LBBB and compare it to that of myocardial perfusion scintigraphy (MPS). Methods: Simultaneous transthoracic CFR measurements and MPS were analyzed in 44 consecutive patients with suspected CAD and permanent LBBB. Typical diastolic predominant phasic CFV Doppler spectra of distal LAD were obtained at rest and during a two-step (0.56,0.84 mg/kg) dipyridamole infusion protocol. CFR was defined as the ratio of peak hyperemic velocities to the baseline values. A reversible perfusion defect at LAD territory was accepted as a positive scintigraphy finding for significant LAD stenosis. A coronary angiography was performed within 5 days of the CFR studies. Results: The hyperemic diastolic peak velocity (44 ± 9 cm/sec vs 62 ± 2 cm/sec; P=0.01) and diastolic CFR (1.38 ± 0.17 vs 1.93 ± 0.3; P=0.001) were significantly lower in patients with LAD stenosis compared to those without LAD stenosis. The diastolic CFR values of <1.6 yielded a sensitivity of 100% and a specificity of 94% in the identification of significant LAD stenosis. In comparison, MPS detected LAD stenosis with a sensitivity of 100% and a specificity of 29%. Conclusions: CFR measurement by transthoracic Doppler echocardiography is an accurate method that may improve noninvasive identification of LAD stenosis in patients with LBBB. [source]

Noninvasive Assessment of Coronary Flow Reserve in the Left Anterior Descending Artery by Transthoracic Echocardiography before and after Stenting

ECHOCARDIOGRAPHY, Issue 8 2007
Elie Chammas M.D., F.E.S.C.
Background: Noninvasive assessment of coronary flow reserve in the left anterior descending artery (LAD) by transthoracic Doppler echocardiography (TTDE) has been already validated as a new method for determining the degree of stenosis over the proximal flow. Objectives: The aim of the study is to determine, by TTDE, the feasibility and the value of the coronary flow reserve (CFR) (defined as the maximal increase in coronary blood flow above its basal pressure for a given perfusion pressure when coronary circulation is maximally dilated) in the mid-to-distal LAD before and after percutaneous angioplasty and to demonstrate the early recovery of microvascular tone immediately after stenting. Methods: The study population consisted of 36 patients with significant isolated LAD stenosis (70,90%) identified by coronary angiography. CFR was recorded in the mid-to-distal LAD at rest and during hyperemia obtained after adenosine intravenous infusion before and after stenting. Results: Adequate visualization of the LAD was obtained in 25 out of 36 patients (70%). At rest the mean CFR was 1.5132 ± 0.33 (1.1,2.58). However, after stenting the mean CFR was significantly higher: 2.18 ± 0.55 (1.3,3.8), with P <0.01. Conclusions: CFR can be easily determined by TTE in approximately 70% of patients. Noninvasive Doppler echocardiography shows impaired CFR in patients with LAD disease. After stenting CFR is restored, demonstrating early recovery of microvascular tone. These results are comparable to those published in the same conditions. Larger series with a long-term follow-up may allow identifying patients at high risk for restenosis after stenting. [source]

Catheter-based ventricle-coronary vein bypass

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005
Motoya Hayase MD
Abstract The goal of this study was to investigate the feasibility of a catheter-based ventricle-to-coronary vein bypass (VPASS) in order to achieve retrograde myocardial perfusion by a conduit (VSTENT) from the left ventricle (LV) to the anterior interventricular vein (AIV). Percutaneous coronary venous arterialization has been proposed as a potential treatment strategy for otherwise untreatable coronary artery disease. In an acute setting, the VSTENT implant was deployed percutaneously using the VPASS procedure in five swine. Coronary venous flow and pressure patterns were measured before and after VSTENT implant deployment with and without AIV and left anterior descending artery (LAD) occlusion. In a separate chronic pilot study, the VPASS procedure was completed on two animals that had a mid-LAD occlusion or LAD stenosis. At day 30 post-VPASS procedure, left ventriculography and magnetic resonance imaging (MRI) were performed to assess the patency and myocardial viability of the VSTENT implants. Pre-VSTENT implantation, the mid-AIV systolic wedge pressure was significantly lower than LV systolic pressure during AIV blockage (46 ± 19 vs. 90 ± 16 mm Hg; P < 0.01). The VSTENT implant deployment was performed without complication and achieved equalization of the AIV and LV systolic pressures and creation of retrograde flow in the distal AIV (maximal flow velocity: 37 ± 7 cm/sec). At day 30 post-VPASS procedure, left ventriculography showed VSTENT implant patency. MRI perfusion images demonstrated myocardial viability even with an LAD occlusion. Coronary retrograde perfusion using the VPASS procedure is feasible and may represent a potential technique for end-stage myocardial ischemia. Catheter Cardiovasc Interv 2005. © 2005 Wiley-Liss, Inc. [source]

Elective sirolimus-eluting stent implantation for multivessel disease involving significant LAD stenosis: One-year clinical outcomes of 99 consecutive patients,the Rotterdam experience

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2004
Chourmouzios A. Arampatzis MD
Abstract The aim of this study was to evaluate the effectiveness of sirolimus-eluting stent (SES) implantation for patients with multivessel disease, which included left anterior descending artery (LAD) treatment. Since April 2002, SES has been utilized as the device of choice for all interventions in our institution as part of the Rapamycin-Eluting Stent Evaluated at Rotterdam Hospital (RESEARCH) registry. In the first 6 months of enrolment, 99 consecutive patients (17.6% of the total population) were treated for multivessel disease involving the LAD. The impact of SES implantation on major adverse cardiac events (MACE) was evaluated. All the patients received SES in the LAD. Additional stent implantation in the right coronary artery, the left circumflex, or in all three major vessels was attempted successfully in 32 (32%), 51 (52%), and 16 (16%) of the treated patients respectively. During a mean follow-up of 360 ± 59 days (range, 297,472 days), we had one death, one non-Q-wave myocardial infarction, and eight patients required subsequent intervention. The event-free survival of MACE at 1 year was 85.6%. SES implantation for multivessel disease in a consecutive series of patients is associated with low incidence of adverse events. The reported results are related predominantly to the reduction in repeat revascularization. Catheter Cardiovasc Interv 2004;63:57,60. © 2004 Wiley-Liss, Inc. [source]