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LAD
Terms modified by LAD Selected AbstractsLosartan decreases vasopressin-mediated cAMP accumulation in the thick ascending limb of the loop of Henle in rats with congestive heart failureACTA PHYSIOLOGICA, Issue 4 2007M. Torp Abstract Introduction:, Vasopressin (AVP) stimulates sodium reabsorption and Na,K,2Cl-cotransporter (NKCC2) protein level in the thick ascending limb (TAL) of Henle's loop in rats. Rats with congestive heart failure (CHF) have increased protein level of NKCC2, which can be normalized by angiotensin II receptor type-1 (AT1) blockade with losartan. Aim:, In this study, we investigated whether CHF rats displayed changes in AVP stimulated cAMP formation in the TAL and examined the role of AT1 receptor blockade on this system. Method:, CHF was induced by ligation of the left anterior descending coronary artery (LAD). SHAM-operated rats were used as controls. Half of the rats were treated with losartan (10 mg kg day,1 i.p.). Results:, CHF rats were characterized by increased left ventricular end diastolic pressure. Measurement of cAMP in isolated outer medullary TAL showed that both basal and AVP (10,6 m) stimulated cAMP levels were significantly increased in CHF rats (25.52 ± 4.49 pmol cAMP ,g,1 protein, P < 0.05) compared to Sham rats (8.13 ± 1.14 pmol cAMP ,g,1 protein), P < 0.05). Losartan significantly reduced the basal level of cAMP in CHF rats (CHF: 12.56 ± 1.93 fmol ,g,1 protein vs. Los-CHF: 7.49 ± 1.08, P < 0.05), but not in Sham rats (SHAM: 4.66 ± 0.59 vs. Los-SHAM: 4.75 ± 0.71). AVP-mediated cAMP accumulation was absent in both groups treated with losartan (Los-SHAM: 4.75 ± 0.71 and Los-CHF: 7.49 ± 1.08). Conclusion:, The results indicate that the increased NKCC2 protein level in the mTAL from CHF rats is associated with increased cAMP accumulation in this segment. Furthermore, the finding that AT1 receptor blockade prevents AVP-mediated cAMP accumulation in both SHAM and CHF rats suggests an interaction between angiotensin II and AVP in regulation of mTAL Na reabsorption. [source] Overexpression of CD7 in classical Hodgkin lymphoma-infiltrating T lymphocytes,CYTOMETRY, Issue 3 2009Adam C. Seegmiller Abstract Background: Diagnosis of Hodgkin lymphoma (HL) is sometimes complicated by the scarcity of neoplastic cells in a reactive inflammatory background. Immunophenotyping by flow cytometry (FC) has not played a significant role in HL diagnosis because of its consistent failure to identify these neoplastic cells. However, HL-infiltrating T cells have been shown to play a role in HL pathogenesis. This study characterizes the FC immunophenotype of these T lymphocytes to determine whether they can be used to assist in the diagnosis of HL. Methods: Cell suspensions from 76 lymph nodes involved by HL and 156 lymph nodes with reactive lymphadenopathy (LAD) were analyzed by flow cytometry to assess the expression of T-cell antigens. Results: The CD4:CD8 ratio and CD7 expression in both CD4(+) and CD8(+) T cells are increased in HL compared with reactive lymph nodes and there are significant differences between these features in different subtypes of HL. However, only the expression of CD7 in CD4(+) T cells distinguishes between HL and reactive LAD. This is especially true for classical HL in younger patients. Using a CD7 mean fluorescence intensity (MFI) cutoff value generated by this data, 37/47 FNA specimens were correctly diagnosed. Conclusions: There are significant differences in the immunophenotypes of HL-infiltrating T cells. Of these, the CD7 expression in CD4(+) T cells discriminates between HL and reactive LAD, suggesting that this could be a useful and practical adjunctive tool in the diagnosis of HL. It may also further our understanding of the pathophysiology of this disease. © 2008 Clinical Cytometry Society [source] Resting Echocardiography for the Early Detection of Acute Coronary Syndromes in Chest Pain Unit PatientsECHOCARDIOGRAPHY, Issue 6 2010Vito Maurizio Parato M.D. Aim: The purpose of this study is to assess the ability of resting echocardiography to detect an acute coronary syndrome (ACS) before the occurrence of ischemic electrocardiogram (ECG) changes or troponin-T elevations. Methods: Four hundred and three patients who presented to the emergency room (ER) with chest pain, normal ECGs, and normal troponin-T levels were admitted to the cardiologist-run Chest Pain Unit (CPU) for further monitoring. They underwent serial resting echocardiography for monitoring of left ventricle wall motion (LVWM), ECG telemetry monitoring, and serial troponin-T measurements. Results: An ACS was detected in 49 patients (12.1%). These 49 patients were then subdivided into three different groups based on the initial mode of detection of their ACS. In group A, 16 of 49 (32.6%) patients had ACS shown by echocardiographic detection of LVWM abnormalities. In group B, 24 of 49 (48.9%) patients had an ACS detected by ischemic ECG changes. In group C, 9 of 49 (18.3%) patients had an ACS detected by troponin-T elevations. The shortest time interval between CPU-admission and ACS-detection occurred in group A (A vs. B, P < 0.003; A vs. C, P < 0.0001). In group A, cardiac angiogram showed that the culprit coronary lesion was more frequent in the circumflex artery (11 out of 16; 68.7%) (LCx vs. LAD, P < 0.02; LCx vs. RCA, P < 0.001) and of these 11 patients with circumflex lesions, the ECG was normal in eight (72.7%) patients. Conclusion: This study demonstrates the utility of LVWM monitoring by serial echocardiography as part of a diagnostic protocol that can be implemented in a CPU. Furthermore, echocardiography could become an essential tool used in the diagnosis of ACS secondary to circumflex lesions. (Echocardiography 2010;27:597-602) [source] Evaluation of Subendocardial and Subepicardial Left Ventricular Functions Using Tissue Doppler Imaging after Complete RevascularizationECHOCARDIOGRAPHY, Issue 2 2009Hüseyin Sürücü M.D. Objective: We aim to evaluate subepicardial and subendocardial left ventricular (LV) functions in patient single coronary artery lesion at early stage after percutaneous coronary intervention (PCI). Additionally, a comparison of LV functions between patients and control cases was aimed. Method: Patients with culprit left anterior descending (LAD) lesion (n = 25) and subjects with normal coronary angiography (n = 25) were evaluated. Patients underwent PCI and at least one coronary stent was placed. After PCI, the pulsed-wave tissue Doppler imaging (pw-TDI) parameters taken from subepicardial and subepicardial layers were compared among the patients. Results: Left atrium (P = 0.050), LV end-diastolic (P = 0.049), and end-systolic (P = 0.006) diameters were larger compared to the control group. LV inflow velocities were not different between the patient and the control group. But, the myocardial performance index was different (P = 0.049). The systolic and diastolic pw-TDI parameters were apparently different between the patient and the control group. While the systolic pw-TDI parameters did not change, the diastolic pw-TDI parameters taken from both subepicardial (circumferential contraction) and subendocardial layers (longitudinal contraction) improved after PCI. After PCI, it was shown that while Ea velocity (P = 0.012) taken from the subendocardial layer increased, IVRa velocity (P < 0.001) taken from the subepicardial layer decreased. Conclusion: In our study, it could be said that LV, left atrium, and aortic valve diameter increase in patients with coronary artery disease. The systolic and diastolic functions were impaired at subendocardial and subepicardial layers. These dysfunctions can be easily presented with pw-TDI. Although systolic dysfunction persists, diastolic dysfunction improves at early stage after PCI. [source] Transthoracic Doppler Echocardiographic Coronary Flow Imaging in Identification of Left Anterior Descending Coronary Artery Stenosis in Patients with Left Bundle Branch BlockECHOCARDIOGRAPHY, Issue 10 2008Ozer 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] Proximal Coronary Hemodynamic Changes Evaluated by Intracardiac Echocardiography during Myocardial Ischemia and Reperfusion in a Canine ModelECHOCARDIOGRAPHY, Issue 3 2008Beibei Han M.D. Background: The purpose of this study was to assess whether the dynamic changes in coronary flow velocity and coronary flow velocity reserve (CFVR) by intracardiac echocardiography (ICE) within proximal coronary arteries are related to myocardial perfusion status and infarct size in a myocardial ischemia-reperfusion injury model. Methods: In 14 dogs, left anterior descending coronary artery (LAD) was ligated for 2 hours followed by 2 hours reperfusion. Coronary flow velocity was obtained by ICE within coronary arteries at baseline, and at the end of both occlusion and reperfusion period. The CFVR was calculated as the ratio of hyperemic to resting peak diastolic velocity (PDV). Myocardial perfusion was evaluated by real time myocardial contrast echocardiography (MCE). The infarct area was detected by triphenyltetrazolium chloride (TTC) staining and expressed as the percentage of the whole left ventricular (LV) area. Results: CFVR significantly decreased both in proximal LAD and left circumflex (LCx) artery at the end of occlusion, and did not recover at the end of reperfusion. However, no significant difference in flow parameters was observed between dogs with myocardial perfusion defect and those without. CFVR in LAD at the end of reperfusion did not correlate with the infarct size (r =,0.182, P = NS) either. Conclusions: Decreased CFVR detected by ICE occurs both in ischemic and in nonischemic proximal arteries during myocardial ischemia and early stage of reperfusion. This change in CFVR has poor correlation with the extent of microvascular impairment and cannot be used to predict infarct size. [source] Effect of Sildenafil Citrate (Viagra) on Coronary Flow in Normal SubjectsECHOCARDIOGRAPHY, Issue 1 2008Fuminobu Ishikura M.D. Background: The purpose of this study was to evaluate the effect of sildenafil citrate (Viagra) on coronary function in normal subjects. Methods: The study assessed mean blood pressure, left anterior descending coronary artery (LAD) flow, and echocardiographic variables before and 30 and 60 minutes after taking 50 mg of sildenafil citrate. The mean velocity of LAD flow was assessed with Doppler flow imaging. The study subjects were 6 healthy male volunteers (mean age 37 years). Results: The mean velocity of LAD flow increased 60 minutes after taking sildenafil citrate, but there were no other changes. Two volunteers felt mild flashing and one had mild headache during the study. Conclusion: Sildenafil citrate caused vasodilatation in a normal coronary artery without systemic pressure drops. These results suggest that the agent itself did not have negative effects on the heart in normal subjects. [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] Comparison of Coronary Flow Velocities Between Patients with Obstructive and Nonobstructive Type Hypertrophic Cardiomyopathy: Noninvasive Assessment by Transthoracic Doppler EchocardiographyECHOCARDIOGRAPHY, Issue 1 2005Seden Celik M.D. Background: We aimed to compare coronary flow velocity (CFV) measurements of patients with nonobstructive (NHCM) and obstructive hypertrophic cardiomyopathy (HOCM) by using transthoracic Doppler echocardiography (TTDE). Methods and Results: In 11 patients with NHCM and 26 with HOCM, CFV in the distal left anterior descending (LAD) coronary was measured by TTDE (3.5 MHz) under the guidance of color Doppler flow mapping in addition to standard 2D and Doppler echocardiography. The results were compared with 24 normal participants who had no evidence of cardiac disease. Peak diastolic velocity of LAD was also higher in NHCM and HOCM than controls (52 ± 14 cm/sec and 54 ± 20 cm/sec vs 41 ± 11 cm/sec, respectively, P < 0.01). The analysis of systolic velocities revealed abnormal flow patterns in 16 (61%) patients with HOCM (12 systolic-reversal flow and 4 no systolic flow) and 6 (54%) (5 reversal flow and 1 zero flow) patients with NHCM (,11 ± 30 cm/sec and ,13 ± 38 cm/sec, vs 24 ± 9 cm/sec, respectively, P < 0.001). Linear regression analysis demonstrated no correlation between intraventricular pressure gradient and coronary flow velocities in HOCM patients. However, there were significant positive and negative correlations between septal thickness and diastolic and systolic velocities, respectively (r = 0.50, P < 0.002, and r =,0.43, P < 0.005). Conclusion: We conclude that the coronary flow velocity abnormalities are independent from the type of hypertrophic cardiomyopathy. [source] Noninvasive Coronary Flow Velocity Reserve Measurement in the Posterior Descending Coronary Artery for Detecting Coronary Stenosis in the Right Coronary Artery Using Contrast-Enhanced Transthoracic Doppler EchocardiographyECHOCARDIOGRAPHY, Issue 3 2004Hiroyuki Watanabe M.D. Background: Coronary flow velocity reserve (CFVR) measurement by transthoracic Doppler echocardiography (TTDE) has been found to be useful for assessing left anterior descending coronary artery (LAD) stenosis. However, this method has been restricted only for the LAD. The purpose of this study was to detect severe right coronary artery (RCA) stenosis by CFVR measurement using contrast-enhanced TTDE. Methods: In 60 consecutive patients with angina pectoris (mean (SD) age: 60 (11), 18 women), coronary flow velocities in the RCA were recorded in the postero-descending coronary artery by contrast-enhanced TTDE at rest and during hyperemia induced by intravenous infusion of adenosine triphosphate (140 mcg/ml/kg). CFVR was calculated as the ratio of hyperemic to basal peak and mean diastolic flow velocity. CFVR measurements by TTDE were compared with the results of coronary angiography performed within 1 week. Results: Coronary flow velocity was successfully recorded in 49 (82%) of the 60 patients with contrast agent. CFVR (mean (SD)) was 1.4 (0.4) in patients with, and 2.6 (0.6) in patients without significant stenosis in the RCA (%diameter stenosis > 75%, P < 0.001). Using the cutoff value 2.0 for CFVR in the RCA, its sensitivity and specificity in detecting significant stenosis in the RCA were 88% and 91%, respectively. Conclusion: CFVR measurement in the postero-descending coronary artery by contrast enhanced TTDE is a new, noninvasive method to detect significant stenosis in the RCA. (ECHOCARDIOGRAPHY, Volume 21, April 2004) [source] Is Left Ventricular Diastolic Thickening Documented During Dobutamine and Pacing Stress Echocardiography Related to Myocardial Ischemia?ECHOCARDIOGRAPHY, Issue 1 2002An Animal Model Study Transient increase in diastolic wall thickness (pseudohypertrophy) during pacing stress echocardiography has been reported in normal myocardium. To evaluate the occurrence of pseudohypertrophy and to investigate the contribution of myocardial ischemia on its production during pacing and dobutamine stress echocardiography, we produced a physiologically significant coronary stenosis in 14 open chest dogs. The stenosis in the circumflex artery was measured by quantitative coronary angiography (range: 50% to 89% reduction in luminal diameter), and no resting segmental wallmotion abnormalities were observed by epicardial echocardiography (short-axis, papillary level). In each study, dobutamine (5,40 ,g/kg/min) and pacing (up to 260 beats/min) were performed randomly. Positivity of stress echocardiography tests was quantitatively determined by a significant (P < 0.05) reduction or failure to increase in absolute and percent systolic wall thickening in the myocardial area supplied by the stenotic artery as compared to the left anterior descending (LAD) artery-related areas. Diastolic wall thickness and left ventricular diastolic area were compared before and after each stress test in the circumflex and LAD artery-related regions. Pseudohypertrophy was observed in 57% and 86% of dogs for pacing and dobutamine, respectively, in the circumflex region, and in 50% and 64% in the LAD region. Despite its increased incidence in the circumflex region, the augmented diastolic wall thickness did not correlate with coronary stenosis severity or stress test positivity, but correlated inversely with changes in left ventricular diastolic area. In addition, it correlated directly with changes in heart rate only for pacing. In conclusion, pseudohypertrophy was a frequent finding during pacing and dobutamine stress echocardiography tests but was not related to myocardial ischemia in this animal model. [source] Effects of percutaneous transluminal coronary angioplasty on coronary adenosine concentrations in humansEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2 2000Paganelli Background Even minimal amounts of adenosine is released during myocardial ischemia. Its role in coronary blood flow has been extensively studied, but little is known about its behaviour during percutaneous transluminal angioplasty (PTCA) in man. Material and methods Using in situ samples the aim of this study was to evaluate adenosine plasma concentration before and after PTCA. Ten patients (8 men and 2 women, mean age 65 ± 9 years) with a single stenosis of the left anterior descending coronary artery (LAD) of at least 70% and 10 healthy volunteers (4 men and 6 women, mean age 55 ± 9 years) were included in the study. Results and discussion We found that there is a close relationship between the degree of the stenosis and the adenosine concentrations in the great cardiac vein and in the LAD, and that after PTCA there is a drop in adenosine concentration downstream from the stenosis. This study confirms the crucial role of adenosine in coronary blood flow control. [source] Rats bred for high alcohol drinking are more sensitive to delayed and probabilistic outcomesGENES, BRAIN AND BEHAVIOR, Issue 7 2008C. J. Wilhelm Alcoholics and heavy drinkers score higher on measures of impulsivity than nonalcoholics and light drinkers. This may be because of factors that predate drug exposure (e.g. genetics). This study examined the role of genetics by comparing impulsivity measures in ethanol-naive rats selectively bred based on their high [high alcohol drinking (HAD)] or low [low alcohol drinking (LAD)] consumption of ethanol. Replicates 1 and 2 of the HAD and LAD rats, developed by the University of Indiana Alcohol Research Center, completed two different discounting tasks. Delay discounting examines sensitivity to rewards that are delayed in time and is commonly used to assess ,choice' impulsivity. Probability discounting examines sensitivity to the uncertain delivery of rewards and has been used to assess risk taking and risk assessment. High alcohol drinking rats discounted delayed and probabilistic rewards more steeply than LAD rats. Discount rates associated with probabilistic and delayed rewards were weakly correlated, while bias was strongly correlated with discount rate in both delay and probability discounting. The results suggest that selective breeding for high alcohol consumption selects for animals that are more sensitive to delayed and probabilistic outcomes. Sensitivity to delayed or probabilistic outcomes may be predictive of future drinking in genetically predisposed individuals. [source] Exogenous Glycinebetaine and Salicylic Acid Application Improves Water Relations, Allometry and Quality of Hybrid Sunflower under Water Deficit ConditionsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2009M. Hussain Abstract Limited water availability hampers the sustainability of crop production. Exogenous application of glycinebetaine (GB) and salicylic acid (SA) has been found very effective in reducing the adverse effects of water scarcity. This study was conducted to examine the possible role of exogenous GB and SA application in improving the growth and water relations of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation, viz. control (normal irrigations), water stress at budding stage (irrigation missing at budding stage) and water stress at flowering stage (FS) (irrigation missing at FS). GB and SA were applied exogenously at 100 and 0.724 mm respectively, each at the budding and FS. Control plants did not receive application of GB and SA. Water stress reduced the leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), leaf relative water contents, water potential, osmotic potential, turgor pressure, achene yield and water use efficiency. Nevertheless, exogenous GB and SA application appreciably improved these attributes under water stress. However, exogenous GB application at the FS was more effective than other treatments. Net assimilation rate was not affected by water stress as well as application of GB and SA. The protein contents were considerably increased by water stress at different growth stages, but were reduced by exogenous GB and SA application. The effects of water stress and foliar application of GB were more pronounced when applied at FS than at the budding stage. Moreover, exogenous GB application was only advantageous under stress conditions. [source] Left Internal Mammary Artery (LIMA) Flow Reserve in Ischemic Hypertrophied HeartsJOURNAL OF CARDIAC SURGERY, Issue 1 2009Tomas A. Salerno M.D. We, herein, present clinical evidence suggesting that in ischemic hypertrophied hearts, single arterial inflow from the LIMA to multiple grafts based on the LIMA may not be sufficient and may not meet myocardial demands, at least during the early perioperative period. This observation was made in two patients in whom a vein graft, previously based on the LIMA, was also connected to the aorta. By providing additional inflow from the aorta, flows to the LAD significantly increased. [source] Real-time Visualization and Quantification of Retrograde Cardioplegia Delivery using Near Infrared Fluorescent ImagingJOURNAL OF CARDIAC SURGERY, Issue 6 2008Aravind T. Rangaraj M.D. Presently, there exist no established methods to quantitatively assess cardioplegia distribution intraoperatively and determine when retrograde cardioplegia is required. In this study, we evaluate the feasibility of near infrared (NIR) imaging for real-time visualization of cardioplegia distribution in a porcine model. Methods: A portable, intraoperative, real-time NIR imaging system was utilized. NIR fluorescent cardioplegia solution was developed by incorporating indocyanine green (ICG) into crystalloid cardioplegia solution. Real-time NIR imaging was performed while the fluorescent cardioplegia solution was infused via the retrograde route in five ex vivo normal porcine hearts and in five ex vivo porcine hearts status post left anterior descending (LAD) coronary artery ligation. Horizontal cross-sections of the hearts were obtained at proximal, middle, and distal LAD levels. Videodensitometry was performed to quantify distribution of fluorophore content. Results: The progressive distribution of cardioplegia was clearly visualized with NIR imaging. Complete visualization of retrograde distribution occurred within 4 minutes of infusion. Videodensitometry revealed retrograde cardioplegia, primarily distributed to the left ventricle (LV) and anterior septum. In hearts with LAD ligation, antegrade cardioplegia did not distribute to the anterior LV. This deficiency was compensated for with retrograde cardioplegia supplementation. Conclusions: Incorporation of ICG into cardioplegia allows real-time visualization of cardioplegia delivery via NIR imaging. This technology may prove useful in guiding intraoperative decisions pertaining to when retrograde cardioplegia is mandated. [source] Limitations of Right Internal Thoracic Artery to Left Anterior Descending Artery Bypass: A Comparative Quantitative Study of Postoperative Angiography of the Bilateral Internal Thoracic Artery Bypass GraftsJOURNAL OF CARDIAC SURGERY, Issue 4 2008Mizuho Imamaki M.D. Methods: The 111 subjects underwent graft angiography after bypass grafting of the left or right internal thoracic artery (ITA) to the LAD. The vascular caliber was measured at the origin of the ITA, at an ITA site adjacent to the anastomotic site, and at an LAD site immediately below the anastomotic site, regarding the outer diameter of the catheter as a reference. Results: The caliber of the ITA immediately above the anastomotic site of the LAD was significantly lower in the RITA group. In the left internal thoracic artery (LITA) group, no patient showed a caliber of less than 1.25 mm, but five patients (7.8%) did in the RITA group. The preoperative cardio-thoracic ratio was significantly higher than that in patients in whom the caliber of the ITA immediately above the anastomotic site was 1.25 mm or more, and the height was significantly lower. Conclusions: In many patients, the RITA is appropriate as a graft material to the LAD. However, in patients with a high cardio-thoracic ratio and those with a low height, the RITA may not reach the LAD in a favorable state, and the LITA should be anastomosed to the LAD in some patients. [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] A New Technique for the Old Arterial Graft: Internal Thoracic ArteryJOURNAL OF CARDIAC SURGERY, Issue 2 2008Ufuk Tutun M.D. It stays patent well in the long-term period, and this evidence is directly related to the superior later outcome in terms of longevity. Coronary artery bypass grafting with multiarterial grafts can be performed safely, and better long-term result can be expected with the use of arterial conduits, especially ITA. We describe a simple and practical technique for the left ITA grafting by dividing the ITA graft and using its proximal and distal parts in situ for the distal left anterior descending (LAD) artery and the obtuse marginal artery grafting. [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] Internal Thoracic Arterial Grafts Evaluation by Multislice CT Scan:JOURNAL OF CARDIAC SURGERY, Issue 6 2004A Preliminary Study The aim of this study is to evaluate the multidetector multislice CT Scan (MCTS) as a means of postoperative evaluation of ITA coronary artery bypass grafts. Methods: Twenty-eight patients having been operated on for coronary artery bypass with ITA during a 6-months period, benefited, 7 days after surgery, from a patency and anastomotic site control of ITA with a MCTS associated with cardiac gating (Light Speed, General Electric, USA). Results: Internal thoracic artery bypasses are visualized perfectly on all their courses, with possibility of 3D reconstructions, showing the relationship between cardiac cavities and the arterial bypasses. The anastomotic site on the LAD was, in selected cases, perfectly visualized. Sequential bypasses with left ITA are well visualized as well as T or Y right-to-left ITA grafts. However, surgical clips create some image artefacts. Conclusions: The postoperative control of ITAs are possible by MCTS with a satisfactory resolution. This makes it possible to check the patency of ITAs, their course on the heart surface, and the location and quality of anastomosis with a noninvasive reproductive method. [source] Does Off-Pump Revascularization Reduce Coronary Endothelial Dysfunction?JOURNAL OF CARDIAC SURGERY, Issue 5 2004Harold L. Lazar M.D. This experimental study sought to determine whether OPCAB reduces endothelial dysfunction, compared to standard cardiopulmonary bypass (CPB) with and without the anticomplement agent soluble complement receptor-1 (sCR1). Methods: In 10 pigs, OPCAB was simulated by snaring the left anterior descending (LAD) artery for 15 minutes followed by 3 hours of reperfusion. On-pump revascularization was simulated in 20 pigs by 15 minutes of LAD occlusion on CPB with cold blood cardioplegic arrest followed by 3 hours of reperfusion. Ten of these animals received sCR1 (10 mg/kg) prior to CPB. Inflammatory response was monitored by percent (%) lung water increase, wall motion scores (WMS) with transthoracic echocardiography where 4 = normal to ,1 = dyskinesia, and endothelial function in the distal LAD with bradykinin-induced coronary artery relaxation using organ chamber methodology. Results: OPCAB had no effect on lung edema (% increase = 1.7 ± 1.4 OPCAB vs. 3.4 ± 0.5 CPB vs. 2.3 ± 0.9 CPB + sCR1) and failed to prevent wall motion changes (WMS = 2.65 ± 0.08 OPCAB vs. 2.70 ± 0.04 CPB vs. 3.10 ± 0.07* CPB + sCR1, *p < 0.01) and coronary endothelial dysfunction (% relaxation = 41 ± 9 OPCAB vs. 40 ± 9 CPB vs. 78 ± 8** CPB + sCR1, **p < 0.001), which was best preserved with sCR1. Conclusions: This study suggests that agents which directly inhibit complement activation such as sCR1 are more important in preventing endothelial dysfunction during coronary revascularization than merely avoiding CPB. [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] Emergency Off-Pump Coronary Artery Bypass (OPCAB) for Left Main Coronary Occlusion Using Rapid Aorto-Coronary PerfusionJOURNAL OF CARDIAC SURGERY, Issue 6 2002Paul Kerr D.O. LAD grafted with sapenous vein and immediate aorto-coronary perfusion. Circumflex grafted and patient taken to ICU. Patient discharged on POD #6 after echo shows normal ventricular with no wall motion abnormality. [source] A Xiphoid Approach for Minimally Invasive Coronary Artery Bypass SurgeryJOURNAL OF CARDIAC SURGERY, Issue 4 2000Federico Benetti M.D. However, opening the pleura has been a limitation of using these approaches. Aim: We used the xiphoid approach as an alternative to opening the pleura and to minimize pain after minimally invasive coronary artery bypass surgery. Methods: We review our surgical experience in 55 patients who underwent minimally invasive direct coronary artery bypass (MIDCAB) surgery through a xiphoid approach between October 1997 and August 1999. Thoracoscopy (n = 31) or direct vision (n = 24) were used for internal mammary artery (IMA) harvesting. Mean patient age was 67 ± 10 years and 65% were men. The mean Parsonnet score was 23 ± 10. Performed anastomoses included left IMA (LIMA) to the left anterior descending (LAD) artery (n = 53), LIMA-to-LAD and saphenous vein graft from the LIMA to the right coronary artery (n = 1), and LIMA-to-LAD and right IMA (RIMA) to right coronary artery (n = 1). Results: Postoperative complications included atrial fibrillation (12%), acute noninfectious pericarditis (12%), and acute renal failure (5%). Mean postoperative length of stay was 4 ± 2 days. Angiography was performed in 16 patients and demonstrated excellent patency of the anastomoses. There was no operative mortality. Actuarial survival was 98% in a mean follow-up period of 11 ± 5 months. Conclusions: Minimally invasive coronary artery bypass can be performed safely through a xiphoid approach with low morbidity, mortality, and a relatively short hospital stay. [source] Correlation of Left Atrial Diameter by Echocardiography and Left Atrial Volume by Computed TomographyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2009IRENE HOF M.D. Introduction: For patients undergoing catheter ablation of atrial fibrillation (AF), left atrial size is a predictor of recurrence of AF during follow-up. For this reason, major clinical trials have used a left atrial diameter (LAD) of more than 5.0 or 5.5 cm, assessed by echocardiography, as an exclusion criterion for patients deemed candidates for ablation of AF. However, whether LAD accurately reflects true left atrial size has not been systematically investigated. Therefore, the purpose of this study was to test the hypothesis that LAD, measured by echocardiography, accurately correlates to left atrial volume measured by computed tomography (CT). Methods and Results: We included 50 patients (mean age 56 ± 12 years, five female) with symptomatic AF (40% paroxysmal, 60% persistent), referred for catheter ablation. In each patient, transthoracic echocardiography was performed. Additionally, all patients underwent CT using a 64-slice CT scanner. Left atrial volume was calculated by manually tracing left atrial area on each CT cross-sectional image. Patients had a mean LAD measured by echocardiography of 4.5 ± 0.7 cm, ranging from 2.9 to 5.7 cm. Left atrial volume measured by CT ranged from 67 mL to 270 mL with a mean value of 146 ± 49 mL. A poor correlation was noted between LAD and left atrial volume, r = 0.49 (P < 0.001). Conclusion: LAD measured by echocardiography correlates poorly with left atrial volume measured by CT in patients with AF. As a result, selecting patients with AF for treatment with catheter ablation should not be based on an echocardiographic-derived LAD alone. [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] Inflammatory Cytokine Imbalance after Coronary Angioplasty: Links with Coronary AtherosclerosisJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2007NATALE DANIELE BRUNETTI M.D., Ph.D. Aim:To investigate release of some inflammatory cytokines (Cys) after coronary angioplasty and its links with coronary atherosclerosis. Methods:Twenty-seven consecutive subjects with acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI) were enrolled in the study: serial blood samples were taken in order to evaluate plasma concentrations of Interleukin (IL)-2, IL-10, IL-18, TNF,, and IFN, just before PCI at 12 and 24 hours. Patients were then divided, considering balance between each inflammatory Cy and IL-10, an antiinflammatory Cy, into four groups, ranging from a prevalent antiinflammatory response (stable inflammatory Cy,increasing IL-10 values) to a marked inflammatory imbalance (increasing inflammatory Cy,stable IL-10 values). Results:All Cys showed significant increases in plasma concentrations if compared with baseline values. Release curves were not significantly different when comparing subjects with ST-elevation myocardial infarction (STEMI) versus unstable angina,non-STEMI (UA-NSTEMI), diabetics versus controls. Subjects with marked inflammatory response showed a higher incidence of stenosis on left anterior descending (LAD) coronary artery (IL-2 ,2 and IFN, P < 0.05); Cy release was higher in patients with multivessel coronary disease (IL-2 and IFN,, ANOVA P < 0.01). Correlations were also referable between Cys and myocardial enzyme release. Subjects treated with sirolimus-eluting stents (SES) showed significantly lower Cy periprocedure ratio if compared with those treated with bare metal stents. Conclusions:A significant Cy release is detectable after PCI: inflammatory response seems to correlate with both PCI due to plaque instabilization and coronary atherosclerosis. A blunted inflammatory response is detectable in subjects treated with SES. [source] 3D coronary motion tracking in swine models with MR tracking cathetersJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2009Ehud J. Schmidt PhD Abstract Purpose To develop MR-tracked catheters to delineate the three-dimensional motion of coronary arteries at high spatial and temporal resolution. Materials and Methods Catheters with three tracking microcoils were placed into nine swine. During breath-holds, electrocardiographic (ECG)-synchronized 3D motion was measured at varying vessel depths. 3D motion was measured in American Heart Association left anterior descending (LAD) segments 6,7, left circumflex (LCX) segments 11,15, and right coronary artery (RCA) segments 2,3, at 60,115 beats/min heart rates. Similar-length cardiac cycles were averaged. Intercoil cross-correlation identified early systolic phase (ES) and determined segment motion delay. Results Translational and rotational motion, as a function of cardiac phase, is shown, with directionality and amplitude varying along the vessel length. Rotation (peak-to-peak solid-angle RCA ,0.10, LAD ,0.06, LCX ,0.18 radian) occurs primarily during fast translational motion and increases distally. LCX displacement increases with heart rate by 18%. Phantom simulations of motion effects on high-resolution images, using RCA results, show artifacts due to translation and rotation. Conclusion Magnetic resonance imaging (MRI) tracking catheters quantify motion at 20 fps and 1 mm3 resolution at multiple vessel depths, exceeding that available with other techniques. Imaging artifacts due to rotation are demonstrated. Motion-tracking catheters may provide physiological information during interventions and improve imaging spatial resolution. J. Magn. Reson. Imaging 2009;29:86,98. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||