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Descending Artery (descending + artery)
Kinds of Descending Artery Selected AbstractsNoninvasive Assessment of Coronary Flow Reserve in the Left Anterior Descending Artery by Transthoracic Echocardiography before and after StentingECHOCARDIOGRAPHY, Issue 8 2007Elie 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] A Safe Technique of Exposing of a "Hidden" Left Anterior Descending Artery by Apostolakis et al.JOURNAL OF CARDIAC SURGERY, Issue 6 2007Oz M. Shapira M.D.Article first published online: 25 NOV 200 No abstract is available for this article. [source] Cutting Balloon Angioplasty for Ostial Lesions of the Left Anterior Descending ArteryJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2000TERUO INOUE M.D. We evaluated the effectiveness of Cutting Balloon angioplasty for ostial lesions of the left anterior descending artery compared with conventional balloon angioplasty. Cutting Balloon angioplasty (n = 7) produced larger acute gain (1.70 ± 0.37 vs 0.48 ± 0.25 mm, P < 0.001) and smaller late loss index (0.54 ± 0.55 vs 1.32 ± 0.81, P < 0.05) than conventional balloon angioplasty (n = 7). As a result, late restenosis was seen in only two patients undergoing Cutting Balloon angioplasty, but in all seven patients undergoing conventional balloon angioplasty. Ostial lesions of the left anterior descending artery may be one of the suitable targets of Cutting Balloon angioplasty. (J Interven Cardiol 2000;13:7,14) [source] Single Coronary Artery: Right Coronary Artery Originated From Middle of Left Anterior Descending Artery in a Patient With Severe Mitral RegurgitationCLINICAL CARDIOLOGY, Issue 4 2010Murat Meric MD The single coronary artery is a benign and very rare coronary artery abnormality. Anomalous origin of the right coronary artery originating from the left anterior descending artery has been reported previously in just a few cases. In this article, we presented a patient with an anomalous origin of the right coronary artery from the midportion of the left anterior descending artery. The anomalous coronary artery was discovered incidentally during a coronary angiography performed prior to mitral valve surgery. Copyright © 2010 Wiley Periodicals, Inc. [source] Anomalous Left Anterior Descending Coronary Artery from the Pulmonary Artery, Unroofed Coronary Sinus, Patent Foramen Ovale, and a Persistent Left-sided SVC in a Single Patient: A Harmonious Quartet of DefectsCONGENITAL HEART DISEASE, Issue 2 2009Andrew J. Klein MD ABSTRACT Unroofing of the coronary sinus without complex structural heart defects is a rare congenital defect often seen in conjunction with a persistent left-sided superior vena cava. Anomalous origin of the left anterior descending artery from the pulmonary artery with normal origin of the left circumflex coronary artery is an even rarer congenital cardiac defect. We report a case of a 54-year-old woman presenting with mild dyspnea on exertion who was found on invasive and noninvasive evaluations to have a unique combination of defects,unroofed coronary sinus, persistent left-sided superior vena cava, patent foramen ovale, and anomalous origin of the left anterior descending artery from the pulmonary artery without evidence of previous coronary ischemia. [source] Noninvasive Assessment of Coronary Flow Reserve in the Left Anterior Descending Artery by Transthoracic Echocardiography before and after StentingECHOCARDIOGRAPHY, Issue 8 2007Elie 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] Noninvasive Assessment of Significant Right Coronary Artery Stenosis Based on Coronary Flow Velocity Reserve in the Right Coronary Artery by Transthoracic Doppler EchocardiographyECHOCARDIOGRAPHY, Issue 6 2003M.D., Yoshiki Ueno Background: Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography (TTDE) has been reported to be useful for the noninvasive assessment of coronary stenosis in the left anterior descending artery. However, the measurement of CFVR in the right coronary artery by TTDE has not yet been validated in a clinical study. Objective: The aim of this study was to evaluate whether CFVR by TTDE can detect significant stenosis in the right coronary artery. Methods: We studied 50 patients who underwent coronary angiography. Coronary flow velocity in the posterior descending branch of the right coronary artery (PD) was measured by TTDE both at baseline and during hyperemia induced by the intravenous infusion of adenosine triphosphate. CFVR was calculated as the hyperemia/baseline (average diastolic peak velocity). Results: Adequate spectral Doppler recordings in the PD were obtained in 36 patients including 26 patients who were given an echocardiographic contrast agent to improve Doppler spectral signals. The study population was divided into 2 groups with (Group A;n = 11) and without (Group B;n = 25) significant stenosis in the right coronary artery. CFVR in Group A was significantly smaller than that in Group B (1.6±0.3versus2.5±0.4; P < 0.0001). The sensitivity of a CFVR of <2.0 for predicting the presence of significant stenosis in the right coronary artery was 91%, and the specificity was 88%. Conclusions: The measurement of CFVR in the PD by TTDE is useful for the noninvasive assessment of significant stenosis in the right coronary artery. (ECHOCARDIOGRAPHY, Volume 20, August 2003) [source] Levosimendan cardioprotection in acutely ,-1 adrenergic receptor blocked open chest pigsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2010C. METZSCH Background: Levosimendan and volatile anesthetics have myocardial pre-conditioning effects. ,-1 adrenergic receptor antagonists may inhibit the protective effect of volatile anesthetics. No information exists as to whether this also applies to the pre-conditioning effect of levosimendan. We therefore investigated whether levosimendan added to metoprolol would demonstrate a cardioprotective effect. Methods: Three groups of anesthetized open chest pigs underwent 30 min of myocardial ischemia and 90 min of reperfusion by temporary occlusion of the largest side branch from the circumflex artery or the left anterior descending artery. One group (CTRL) served as a control, in another group (BETA), a metoprolol-loading dose was intravenously injected 30 min before ischemia, and in a third group (BETA+L), a levosimendan infusion was added to metoprolol. Myocardial tissue concentrations of glucose, glycerol, and lactate/pyruvate ratio as the primary end-points were investigated with microdialysis in ischemic and non-ischemic tissues. Results: At the end of the ischemic period, statistically significant differences were only found between CTRL and BETA+L in the ischemic myocardium, with a lower lactate/pyruvate ratio, lower glycerol, and higher glucose concentrations in BETA+L as compared with CTRL. There were no differences in non-ischemic myocardium. From 10 to 90 min of reperfusion, no more differences were found between groups. Conclusion: The cardioprotective effect of levosimendan on ischemic metabolism with a reduction in the myocardial lactate/pyruvate ratio, less glycerol accumulation, and better preserved glucose concentration does not seem to be prevented by ,-1 adrenergic receptor antagonism with metoprolol. [source] Early and Late Outcomes of Multiple Coronary EndarterectomyJOURNAL OF CARDIAC SURGERY, Issue 6 2008Minoru Tabata M.D. However, outcomes of multiple coronary endarterectomy (MCE) have not been well investigated. We sought to examine early and late results of this technique. Methods: Between January 1992 and June 2006, 58 consecutive patients underwent coronary endarterectomy in more than one coronary artery territories, representing 6.5% of total coronary endarterectomy during the same period. Early and late outcomes were retrospectively analyzed. Results: The mean age was 64 years. Forty-one patients (70.7%) had coronary endarterectomy in the left anterior descending artery and right coronary artery territories; five (8.6%) in the left anterior descending artery and circumflex artery territories; eight (13.8%) in the circumflex artery and right coronary artery territories; and four (6.9%) in the left anterior descending artery, circumflex artery, and right coronary artery territories. Operative mortality was 12.1% (7/58). The incidence of perioperative myocardial infarction was 25.9% (15/58). The median length of hospital stay was seven days. Actuarial five- and 10-year survivals were 64% and 36%, respectively. Conclusions: MCE may be a reasonable option for revascularization of multiple diffuse coronary artery disease. However, early and late outcomes are relatively poor and the indication should be carefully considered. [source] The Right Gastroepiploic Artery in Coronary Artery Bypass GraftingJOURNAL OF CARDIAC SURGERY, Issue 4 2008Hideki Sasaki M.D. Although some reports presenting good results justify its use in clinical settings, there is still much concern about using the RGEA in bypass surgery. The RGEA demonstrates different behaviors from the internal thoracic artery (ITA) in bypass surgery due to its histological characteristics and anatomical difference, which might contribute to the long-term outcome. Now that left ITA (LITA) to left anterior descending artery (LAD) is the gold standard, other grafts are expected to cover the rest of the coronary arteries. It should be elucidated how we can use other grafts and what we can expect from them. RGEA, as an arterial graft, can be used as an in situ graft or a free graft. The RGEA is mainly used to graft to the right coronary artery (RCA) because of its anatomical position, and its patency is not inferior to that of the saphenous vein (SVG). The RGEA can cover the lateral walls when its length is long enough or by making a composite graft with other grafts. However, when used to graft to the LAD, its mid-term patency is not favorable. [source] Concomitant Coronary and Peripheral Arterial Disease: Single-Stage RevascularizationJOURNAL OF CARDIAC SURGERY, Issue 3 2008Onur S. Goksel M.D. Coexistence of two entities is usually managed with a staged approach; however, decision to treat which entity first may be difficult clinically. We present a 49-year-old man with acute infrarenal aortic occlusion and cardiac ischemia who was treated with single-stage ascending aorta-bifemoral bypass following saphenous vein grafting to left anterior descending artery. Concomitant coronary and peripheral vascular revascularization is a practical method with a high flow inflow source as ascending aorta. We believe that a single-stage approach may be performed in the unstable patient as presented in this report. [source] Midterm Results of Off-Pump Coronary Artery Bypass Surgery in 136 Patients: An Angiographic Control StudyJOURNAL OF CARDIAC SURGERY, Issue 1 2006Hakki Kazaz M.D. This study summarizes the midterm results of 136 off-pump bypass surgery patients. Methods: Between January 2000 and March 2002, out of 178 surgical myocardial revascularizations, 136 (76.4%) were off-pump bypass surgery. Complete revascularization was done and especially arterial grafts were used. All patients were followed clinically and with treadmill test for 2 years. Average control angiography was performed at the end of 2-year follow-up. Results: Of all the patients, 56.7% were male and the mean age of the patients was 63.6 ± 7.4 years. A total of 481 anastomoses were performed,136 (28.27%) to the left anterior descending artery (LAD), 135 (28.07%) to the circumflex coronary artery (Cx) branches, 102 (21.20%) to the right coronary artery (RCA), 108 (22.46%) to the D,. The mean graft number was 3.46. We used 96.6% of patients' left internal mammarian artery (LITA), 29.2% radial artery (RA), 4.4% right internal thoracic artery (RITA), and 100% saphenous vein. There were ischemic changes within 12 patients. All ischemic changes came back to normal within 4 and 18 hours, postoperatively. Mean extubation time was 5.36 ± 2.23 hours, mean stay in intensive care unit was 17.53 ± 3.15 hours, mean hospital stay was 5.03 ± 1.29 days. The LITA patency was 99.25%, RA patency was 97.84%, RITA patency was 100%, and saphenous vein patency was 91.79% with control angiography. Conclusion: Off-pump coronary artery bypass graft (CABG) is efficient procedure with lower index of mortality, morbidity, ICU stay, hospital stay, good wound healing, early socialization, and results in lower costs. [source] Acute Effect of Cerivastatin on Cardiac Regional Ischemia in a Rat Model Mimicking Off-Pump Coronary SurgeryJOURNAL OF CARDIAC SURGERY, Issue 6 2005Koki Nakamura M.D. The aims of this study were to investigate the optimal duration of coronary occlusion for making reversible ischemia and to examine whether cerivastatin increases myocardial tolerance against prolonged coronary occlusion. Methods: Study 1,Male Sprague-Dawley rats (350 to 450 g) underwent temporary occlusion of either left anterior descending artery (LAD; for 3, 5, 7.5, 10, 12.5, 15, or 20 min) or circumflex artery (CX; for 5, 10, or 15 min). Study 2,Rats were divided into two groups, control and cerivastatin groups, which had 0.1 mg/kg cerivastatin intravenously after anesthesia. LAD was occluded for 10, 15, or 20 minutes. In the both studies, hearts were stained to determine the area at risk (AR) and infarcted (IF) area 24 hours after reperfusion. Results: In LAD occlusion, IF/AR increased in a time dependent manner: 4.5 ± 3.2%, 9.7 ± 5.2%, 17.2 ± 3.0%, 16.8 ± 2.7%, 23.9 ± 9.5% (p < 0.01 vs. 3 min), 62.4 ± 2.9% (p < 0.0001), and 63.4 ± 2.9% (p < 0.0001) at 3, 5, 7.5, 10, 12.5, 15, and 20 min, respectively. Also in CX, IF/AR increased with time: 14.3 ± 2.3%, 25.9 ± 2.1%, and 40.9 ± 6.2% (p < 0.001 vs. 5 min) at 5, 10, and 15 min, respectively. Cerivastatin significantly reduced IF/AR at 15 minutes (43.7 ± 6.2%) and at 20 minutes (44.6 ± 5.3%) compared to control (62.4 ± 2.9% and 60.6 ± 2.5%, respectively, p < 0.05). Conclusion: Cerivastatin increased myocardial tolerance after prolonged coronary occlusion over 10 minutes, which was considered to be the upper limit for creating a regional reversible ischemia in rats. [source] Left Ventricular Aneurysmectomy: Endoventricular Circular Patch Plasty or SeptoexclusionJOURNAL OF CARDIAC SURGERY, Issue 2 2003Antonio Maria Calafiore M.D. Its indications and midterm results are evaluated and compared to those obtained with the Dor operation. Methods: From January 1998 to April 2001, 79 patients had an exclusion of scars following myocardial infarction in left anterior descending artery (LAD) territory. Fifty of them (63.3%) had the Dor operation (Group D) and 29 (36.7%) the Guilmet operation (Group G). Dor technique was used when the involvement of the septum and the free wall was roughly similar. Guilmet technique was indicated when the septum was involved at a greater extent than the free wall. Ejection fraction (EF) was lower and end-diastolic volumes were higher in Group G. Incidence of functional mitral regurgitation was similar in both groups. Results: Thirty-day mortality was 7.6% (8.0% in Group D versus 6.9% in Group G,p = ns). After a mean of21.0 ± 8.5months, five patients (6.9%) died, two in Group D and three in Group G. Causes of death were cardiac related in four and not cardiac related in one. Mean follow-up of the 68 survivors was24.3 ± 12.0months (range: 4-38 months). Fifty patients (73.5% of the survivors) improved (28 in Group D and 22 in Group G,p = 0.026), whereas in 18, New York Heart Association (NYHA) class remained unchanged or worsened. Both groups showed an increase of EF and a volumetric reduction, whereas stroke volume remained unchanged. Fewer patients had mitral regurgitation than in the preoperative period (41.3% versus 65.8%, p = 0.013) and at a lesser extent (1.7 ± 0.7versus0.7 ± 0.6, p < 0.001). Conclusions: Our results show that both Dor and Guilmet techniques are effective in the surgical treatment of left ventricular dyskinetic or akinetic areas related to LAD territory. Each technique has its own indications and has to be addressed to patients with different extension of septal scars.(J Card Surg 2003;18:93-100) [source] Sildenafil-mediated neovascularization and protection against myocardial ischaemia reperfusion injury in rats: role of VEGF/angiopoietin-1JOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 6b 2008Srikanth Koneru Abstract Sildenafil citrate (SC), a drug for erectile dysfunction, is now emerging as a cardiopulmonary drug. Our study aimed to determine a novel role of sildenafil on cardioprotection through stimulating angiogenesis during ischaemia (I) reperfusion (R) at both capillary and arteriolar levels and to examine the role of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) in this mechanistic effect. Rats were divided into: control sham (CS), sildenafil sham (SS), control + IR (CIR) and sildenafil + IR (SIR). Rats were given 0.7 mg/kg, (i.v) of SC or saline 30 min. before occlusion of left anterior descending artery followed by reperfusion (R). Sildenafil treatment increased capillary and arteriolar density followed by increased blood flow (2-fold) compared to control. Treatment with sildenafil demonstrated increased VEGF and Ang-1 mRNA after early reperfusion. PCR data were validated by Western blot analysis. Significant reduction in infarct size, cardiomyocyte and endothelial apoptosis were observed in SC-treated rats. Increased phosphorylation of Akt, eNOS and expression of anti-apoptotic protein Bcl-2, and thioredoxin, hemeoxygenase-1 were observed in SC-treated rats. Echocardiography demonstrated increased fractional shortening and ejection fraction following 45 days of reperfusion in the treatment group. Stress testing with dobutamine infusion and echocardiogram revealed increased contractile reserve in the treatment group. Our study demonstrated for the first time a strong additional therapeutic potential of sildenafil by up-regulating VEGF and Ang-1 system, probably by stimulating a cascade of events leading to neovascularization and conferring myocardial protection in in vivo I/R rat model. [source] Transvenous Intramyocardial Cellular Delivery Increases Retention in Comparison to Intracoronary Delivery in a Porcine Model of Acute Myocardial InfarctionJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2008JON C. GEORGE M.D. Background: Clinical trials using intracoronary (IC) delivery of cells have addressed efficacy but the optimal delivery technique is unknown. Our study aimed to determine whether transvenous intramyocardial (TVIM) approach was advantageous for cellular retention in AMI. Methods: Domestic pigs (n = 4) underwent catheterization with coronary angiography and ventriculography prior to infarction and pre- and post-cells. Pigs underwent 90-minute balloon occlusion of the left anterior descending artery (LAD). After one week they were prepared for IC (n = 2) or TVIM (n = 2) delivery of bone marrow mononuclear cells (MNC) labeled with GFP. IC infusion used an over-the-wire catheter to engage the LAD and balloon inflation to prevent retrograde flow. Venography via the coronary sinus was used for TVIM delivery. The anterior interventricular vein was engaged with a guidewire allowing use of the TransAccessÔ catheter that is outfitted with an ultrasound tip for visualization. Animals were sacrificed one hour after delivery and tissue was analyzed. Results: Procedures were performed without complication and monitoring was uneventful. 1 × 108 MNC were isolated from each bone marrow (BM) preparation and 1 × 107 MNC delivered. Ventriculography at one week revealed wall motion abnormalities consistent with an anterior AMI. TVIM and IC delivery revealed mean 452 cells per section and 235 cells per section on average, respectively, in the infarct zone (P = 0.01). Conclusion: We have demonstrated that TVIM approach for cell delivery is feasible and safe. Moreover, this approach may provide an advantage over IC infusion in retention of the cellular product; however, larger studies will be necessary. [source] Clinical and Angiographic Outcome after Cutting Balloon AngioplastyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2003JOHANN AUER M.D. The cutting balloon is a new device for coronary angioplasty, that, by the combination of incision and dilatation of the plaque, is believed to be promising for treatment of in-stent restenosis. The purpose of the study was to evaluate the safety and efficacy of CBA. We reviewed the immediate and 6-month follow-up angiographic and clinical outcome of 147 patients (109 men and 38 women) with a mean age of67.3 ± 10undergoing this procedure at eight interventional centers in Austria. The target lesions treated with CBA were in-stent restenosis in 61% of patients, stenosis after balloon angioplasty in 8% of patients, and native lesions in 33% of patients. Sixty-five percent of the patients included had multivessel disease. Lesion type was A in 18% of patients, B1 in 31% of patients, B2 in 39% of patients, and C in 12% of patients. The degree of stenosis was87%± 9%,the length of the target lesion treated with CBA was8.8 ± 5.1 mm. Target vessel was left circumflex artery in 22 cases, right coronary artery in 36 cases, and left anterior descending artery in 89 cases. The overall procedural success rate was 90.5%. "Stand-alone" CBA was performed in 63% of patients, the procedure was combined with coronary stenting in 16% of patients, and with balloon angioplasty in 21% of patients. Coronary complications occurred in eight cases (5.4%) with coronary dissection in seven (total dissection rate of 4.7%) and urgent bypass surgery in one case (0.7%). No further complications such as death, occlusion, or perforation of coronary arteries, embolization, or thrombosis were observed. Six-month clinical follow-up revealed q-wave myocardial infarction in 2.7% of patients, aortocoronary bypass surgery in 8.5% of patients, and repeated percutaneous coronary intervention in 17% of patients (11.5% with stenting). Six-month angiographic follow-up of patients with recurrent angina showed target lesion restenosis (>50% diameter stenosis) in 14% of patients, late lumen loss with ,50% diameter stenosis in 6% of patients and progression of "other than target" lesions with >50% diameter stenosis in 14% of patients. This series demonstrates the safety and feasibility of cutting balloon angioplasty in patients with complex coronary artery disease and in-stent restenosis. (J Interven Cardiol 2003;16:15,21) [source] Cutting Balloon Angioplasty for Ostial Lesions of the Left Anterior Descending ArteryJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2000TERUO INOUE M.D. We evaluated the effectiveness of Cutting Balloon angioplasty for ostial lesions of the left anterior descending artery compared with conventional balloon angioplasty. Cutting Balloon angioplasty (n = 7) produced larger acute gain (1.70 ± 0.37 vs 0.48 ± 0.25 mm, P < 0.001) and smaller late loss index (0.54 ± 0.55 vs 1.32 ± 0.81, P < 0.05) than conventional balloon angioplasty (n = 7). As a result, late restenosis was seen in only two patients undergoing Cutting Balloon angioplasty, but in all seven patients undergoing conventional balloon angioplasty. Ostial lesions of the left anterior descending artery may be one of the suitable targets of Cutting Balloon angioplasty. (J Interven Cardiol 2000;13:7,14) [source] Correction for heart rate variability during 3D whole heart MR coronary angiographyJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2008Stijntje D. Roes MD Abstract Purpose To evaluate the effect of a real-time adaptive trigger delay on image quality to correct for heart rate variability in 3D whole-heart coronary MR angiography (MRA). Materials and Methods Twelve healthy adults underwent 3D whole-heart coronary MRA with and without the use of an adaptive trigger delay. The moment of minimal coronary artery motion was visually determined on a high temporal resolution MRI. Throughout the scan performed without adaptive trigger delay, trigger delay was kept constant, whereas during the scan performed with adaptive trigger delay, trigger delay was continuously updated after each RR-interval using physiological modeling. Signal-to-noise, contrast-to-noise, vessel length, vessel sharpness, and subjective image quality were compared in a blinded manner. Results Vessel sharpness improved significantly for the middle segment of the right coronary artery (RCA) with the use of the adaptive trigger delay (52.3 ± 7.1% versus 48.9 ± 7.9%, P = 0.026). Subjective image quality was significantly better in the middle segments of the RCA and left anterior descending artery (LAD) when the scan was performed with adaptive trigger delay compared to constant trigger delay. Conclusion Our results demonstrate that the use of an adaptive trigger delay to correct for heart rate variability improves image quality mainly in the middle segments of the RCA and LAD. J. Magn. Reson. Imaging 2008;27:1046,1053. © 2008 Wiley-Liss, Inc. [source] Three-dimensional MRI assessment of regional wall stress after acute myocardial infarction predicts postdischarge cardiac eventsJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2008Fabrice Prunier MD Abstract Purpose To determine the prognostic significance of systolic wall stress (SWS) after reperfused acute myocardial infarction (AMI) using MRI. Materials and Methods A total of 105 patients underwent MRI 7.8 ± 4.2 days after AMI reperfusion. SWS was calculated by using a three-dimensional (3D) MRI approach to left ventricular (LV) wall thickness and to the radius of curvature. Between hospital discharge and the end of follow-up, an average of 4.1 ± 1.7 years after AMI, 19 patients experienced a major cardiac event, including cardiac death, nonfatal reinfarction or heart failure (18.3%). Results The results were mainly driven by heart failure outcome. In univariate analysis the following factors were predictive of postdischarge major adverse cardiac events: 1) at the time of AMI: higher heart rate, previous calcium antagonist treatment, in-hospital congestive heart failure, proximal left anterior descending artery (LAD) occlusion, a lower ejection fraction, higher maximal ST segment elevation before reperfusion, and ST segment reduction lower than 50% after reperfusion; 2) MRI parameters: higher LV end-systolic volume, lower ejection fraction, higher global SWS, higher SWS in the infarcted area (SWS MI) and higher SWS in the remote myocardium (SWS remote). In the final multivariate model, only SWS MI (odds ratio [OR]: 1.62; 95% confidence interval [CI]: 1.01,2.60; P = 0.046) and SWS remote (OR: 2.17; 95% CI: 1.02,4.65; P = 0.046) were independent predictors. Conclusion Regional SWS assessed by means of MRI a few days after AMI appears to be strong predictor of postdischarge cardiac events, identifying a subset of at risk patients who could qualify for more aggressive management. J. Magn. Reson. Imaging 2008. © 2008 Wiley-Liss, Inc. [source] The circulatory system in Mysidacea,Implications for the phylogenetic position of Lophogastrida and Mysida (Malacostraca, Crustacea)JOURNAL OF MORPHOLOGY, Issue 4 2007Christian S. Wirkner Abstract The morphology of the circulatory organs in Mysida and Lophogastrida (traditionally combined as Mysidacea) is revisited investigating species so far unstudied. In addition to classical morphological methods, a newly developed combination of corrosion casting with micro computer tomography (MicroCT) and computer aided 3D reconstructions is used. Lophogastrida and Mysida show a highly developed arterial system. The tubular heart extends through the greater part of the thorax and is connected with the ventral vessel via an unpaired descending artery. It is suggested that a distinct ostia pattern supports the monophyly of Mysidacea. The cardiac artery system is more complex in Lophogastrida than in Mysida, consisting of up to 10 pairs of arteries that supply the viscera. In both taxa, an anterior and posterior aorta leads off the heart. In the anterior part of the cephalothorax the anterior aorta forms dilations into which muscles are internalized; these structures are called myoarterial formations. One of these myoarterial formations can also be found in all the other peracarid taxa but not in other Malacostraca. J Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Phosphate metabolite concentrations and ATP hydrolysis potential in normal and ischaemic heartsTHE JOURNAL OF PHYSIOLOGY, Issue 17 2008Fan Wu To understand how cardiac ATP and CrP remain stable with changes in work rate , a phenomenon that has eluded mechanistic explanation for decades , data from 31phosphate-magnetic resonance spectroscopy (31P-MRS) are analysed to estimate cytoplasmic and mitochondrial phosphate metabolite concentrations in the normal state, during high cardiac workstates, during acute ischaemia and reactive hyperaemic recovery. Analysis is based on simulating distributed heterogeneous oxygen transport in the myocardium integrated with a detailed model of cardiac energy metabolism. The model predicts that baseline myocardial free inorganic phosphate (Pi) concentration in the canine myocyte cytoplasm , a variable not accessible to direct non-invasive measurement , is approximately 0.29 mm and increases to 2.3 mm near maximal cardiac oxygen consumption. During acute ischaemia (from ligation of the left anterior descending artery) Pi increases to approximately 3.1 mm and ATP consumption in the ischaemic tissue is reduced quickly to less than half its baseline value before the creatine phosphate (CrP) pool is 18% depleted. It is determined from these experiments that the maximal rate of oxygen consumption of the heart is an emergent property and is limited not simply by the maximal rate of ATP synthesis, but by the maximal rate at which ATP can be synthesized at a potential at which it can be utilized. The critical free energy of ATP hydrolysis for cardiac contraction that is consistent with these findings is approximately ,63.5 kJ mol,1. Based on theoretical findings, we hypothesize that inorganic phosphate is both the primary feedback signal for stimulating oxidative phosphorylation in vivo and also the most significant product of ATP hydrolysis in limiting the capacity of the heart to hydrolyse ATP in vivo. Due to the lack of precise quantification of Piin vivo, these hypotheses and associated model predictions remain to be carefully tested experimentally. [source] Diagnostic Significance of a Small Q Wave in Precordial Leads V2 or V3ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Tetsuya Katsuno M.D. Background: An abnormal Q wave is usually defined as an initial depression of the QRS complex having a duration of ,40 ms and amplitude exceeding 25% of the following R wave in any contiguous leads on the 12-lead electrocardiogram (ECG). However, much smaller Q waves are sometimes recorded on the ECG. This study investigated the diagnostic value of the small Q wave recorded in precordial leads V2 or V3 on the ECG. Methods: We investigated 807 consecutive patients who underwent coronary angiography. A small Q wave was defined as any negative deflection preceding the R wave in V2 or V3 with <40-ms duration and <0.5-mV amplitude, with or without a small (<0.1-mV) slurred, spiky fragmented initial QRS deflection before the Q wave (early fragmentation). ECG and coronary angiographic findings were analyzed. Results: The small Q wave was present in 87 patients. Multiple logistic regression analysis revealed that presence of a small Q wave was a strong independent predictor of any coronary artery stenosis or left anterior descending artery (LAD) stenosis (odds ratio = 2.706, 2.902; P < 0.001, < 0.001, respectively). Conclusion: A small Q wave (<40-ms duration and <0.5-mV amplitude) in V2 or V3 with or without early fragmentation significantly predicted the presence of CAD and, especially, significant stenosis in the LAD. Ann Noninvasive Electrocardiol 2010;15(2):116,123 [source] Inferolateral ST Elevation as a First Sign of Left Anterior Descending Artery OcclusionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010Po-Chao Hsu M.D. Combined anterior and inferior ST elevation due to occlusion of wrapped left anterior descending artery (LAD) is well reported in the literature. However, there is rare literature mentioned about inferolateral ST elevation in this patient group. Herein, we report a case of acute proximal wrapped LAD occlusion with initial electrocardiographic sign of inferolateral ST elevation. The most likely mechanism of this electrocardiographic finding might be related to old anteroseptal myocardial infarction, combination with other coronary abnormality, such as chronic total occlusion of left circumflex artery that caused larger injury current in inferolateral than anteroseptal myocardium, and made anteroseptal leads reveal isoelectric pattern. Ann Noninvasive Electrocardiol 2010;15(1):90,93 [source] Utility of Lead aVR for Identifying the Culprit Lesion in Acute Myocardial InfarctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2009B.Sc., Jørgen Tobias Kühl M.A. Background: Lead aVR is a neglected, however, potentially useful tool in electrocardiography. Our aim was to evaluate its value in clinical practice, by reviewing existing literature regarding its utility for identifying the culprit lesion in acute myocardial infarction (AMI). Methods: Based on a systematic search strategy, 16 studies were assessed with the intent to pool data; diagnostic test rates were calculated as key results. Results: Five studies investigated if ST-segment elevation (STE) in aVR is valuable for the diagnosis of left main stem stenosis (LMS) in non,ST-segment AMI (NSTEMI). The studies were too heterogeneous to pool, but the individual studies all showed that STE in aVR has a high negative predictive value (NPV) for LMS. Six studies evaluated if STE in aVR is valuable for distinguishing proximal from distal lesions in the left anterior descending artery (LAD) in anterior ST-segment elevation AMI (STEMI). Pooled data showed a sensitivity of 47%, a specificity of 96%, a positive predicative value (PPV) of 91% and a NPV of 69%. Five studies examined if ST-segment depression (STD) in lead aVR is valuable for discerning lesions in the circumflex artery from those in the right coronary artery in inferior STEMI. Pooled data showed a sensitivity of 37%, a specificity of 86%, a PPV of 42%, and an NPV of 83%. Conclusion: The absence of aVR STE appears to exclude LMS as the underlying cause in NSTEMI; in the context of anterior STEMI, its presence indicates a culprit lesion in the proximal segment of LAD. [source] Altered coronary vasomotor function in young patients with systemic lupus erythematosusARTHRITIS & RHEUMATISM, Issue 6 2007Kumiko Hirata Objective Accelerated atherosclerosis is an important cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Altered coronary microvascular function may act as a marker of changes that predispose to the development of significant coronary vascular disease. The purpose of this study was to compare coronary flow reserve (CFR) in a group of premenopausal women with SLE and a group of age-, sex-, and race-matched healthy control subjects. Methods Coronary flow velocity in 18 premenopausal women with SLE (mean ± SD age 29.4 ± 5.9 years) and 19 matched healthy controls (mean ± SD age 28.2 ± 4.3 years) was assessed by transthoracic Doppler echocardiography after an overnight fast. The CFR was calculated as the ratio of hyperemic to baseline coronary blood flow velocity in the left anterior descending coronary artery. Hyperemia was induced by intravenous administration of adenosine triphosphate. Results The mean ± SD duration of SLE was 8.2 ± 7.2 years (range 0.25,25 years), and the mean ± SD score on the Systemic Lupus Erythematosus Disease Activity Index was 11.0 ± 5.3 (range 4.0,21.0). Adequate recordings of flow velocity in the left anterior descending artery under both conditions were obtained using an ultrasound procedure in all study subjects. CFR was significantly lower in SLE patients as compared with control subjects (mean ± SD 3.4 ± 0.8 versus 4.5 ± 0.5; P < 0.0001). Conclusion These findings provide evidence that coronary vasomotor function is impaired in patients with SLE and support the notion that many of these young patients have subclinical coronary artery disease. [source] Is the left anterior descending artery really absent?,A decisive input from coronary CT angiography,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2010Yalcin Hacioglu MD Abstract This case report emphasizes the importance of coronary CT angiography (CTA) as a backup imaging modality in patients with suspected coronary anomalies and difficult canulation, during invasive coronary angiography by catheterization (Cath). In this patient, the numerous canulation attempts during Cath failed to identify a left anterior descending artery (LAD) leading to the diagnosis of absent LAD. CTA was done for further clarification, which easily visualized LAD originating from a separate ostium at the left sinus of Valsalva finalizing the diagnosis as absent left main artery with dual left coronary ostia. © 2010 Wiley-Liss, Inc. [source] Transcoronary transplantation of autologous mesenchymal stem cells and endothelial progenitors into infarcted human myocardiumCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005Demosthenes G. Katritsis MD PhD Abstract The aim of the study was to investigate whether a combination of mesenchymal stem cells (MSCs) capable of differentiating into cardiac myocytes and endothelial progenitors (EPCs) that mainly promote neoangiogenesis might be able to facilitate tissue repair in myocardial scars. Previous studies have shown that intracoronary transplantation of autologous bone marrow stem cells results in improvement of contractility in infracted areas of human myocardium. Eleven patients with an anteroseptal myocardial infarction (MI) underwent transcoronary transplantation of bone marrow-derived MSCs and EPCs to the infarcted area through the left anterior descending artery. Eleven age- and sex-matched patients served as controls. Wall motion score index was significantly lower at follow-up in the transplantation (P = 0.04) but not in the control group. On stress echocardiography, there was improvement of myocardial contractility in one or more previously nonviable myocardial segments in 5 out of 11 patients (all with recent infarctions) and in none of the controls (P = 0.01). Restoration of uptake of Tc99m sestamibi in one or more previously nonviable myocardial scars was seen in 6 out of 11 patients subjected to transplantation and in none of the controls (P = 0.02). Cell transplantation was an independent predictor of improvement of nonviable tissue. Intracoronary transplantation of MSCs and EPCs is feasible, safe, and may contribute to regional regeneration of myocardial tissue early or late following MI. © 2005 Wiley-Liss, Inc. [source] Catheter-based ventricle-coronary vein bypassCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005Motoya 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 experienceCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2004Chourmouzios 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] | |||||||||||||