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Coronary Artery Stenosis (coronary + artery_stenosis)
Selected AbstractsTransthoracic 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] 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] The Relation Between Mitral Annular Calcification and Mortality in Patients Undergoing Diagnostic Coronary AngiographyECHOCARDIOGRAPHY, Issue 9 2006Howard J. Willens M.D. To determine whether the observed association between mitral annular calcification (MAC) and mortality is independent of the severity of coronary artery disease (CAD), we analyzed data from 134 male veterans (age 63 ± 10 years) followed for 5 years who had undergone diagnostic coronary angiography and transthoracic echocardiography within 6 months of each other. Echocardiograms were retrospectively reviewed for the presence of MAC. The relation of MAC to all-cause mortality was analyzed using logistic regression, and odds ratios (OR) were calculated. MAC was present in 49 (37%) subjects. Over the 5-year follow-up period, 38 (28%) patients expired. Five-year survival was 80% for subjects without MAC and 56% for subjects with MAC (P = 0.003). MAC (OR = 3.16, 95% confidence interval [CI]= 1.43,6.96, P = 0.003), ejection fraction (OR = 0.76, 95% CI = 0.59,0.97, P = 0.02), and left main CAD (OR = 2.70, 95% CI = 1.11,6.57, P = 0.02) were significantly associated with mortality in univariate analysis. After adjusting for left ventricular ejection fraction, number of obstructed coronary arteries and the presence of left main coronary artery stenosis, MAC significantly predicted death (OR = 2.48, 95% CI = 1.09,5.68, P = 0.03). Similarly, after adjusting for predictors of MAC, including ejection fraction, age, diabetes, peripheral vascular disease, and heart failure, MAC remained a significant predictor of death (OR = 2.38, 95% CI = 1.02,5.58, P = 0.04). MAC also predicted death independent of smoking status, hypertension, serum creatinine, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and C-reactive protein levels (OR = 3.98, 95% CI = 1.68,9.40, P = 0.001). MAC detected by two-dimensional echocardiography independently predicts mortality and may provide an easy-to-perform and inexpensive way to improve risk stratification. [source] Regional Response of Myocardial Acceleration During Isovolumic Contraction During Dobutamine Stress Echocardiography: A Color Tissue Doppler Study and Comparison with Angiocardiographic FindingsECHOCARDIOGRAPHY, Issue 10 2005Linda B. Pauliks M.D. Background: Color tissue Doppler imaging permits noninvasive quantitation of regional wall motion. In experimental studies, a new marker, the slope of the isovolumic contraction wave, isovolumic acceleration (IVA) was more insensitive to ventricular loading conditions than myocardial velocities. This study compared the regional response IVA to dobutamine stress echocardiography to angiographic findings. Methods: The Myocardial Doppler in Stress Echocardiography (MYDISE) study prospectively recruited 149 consecutive patients with chest pain for dobutamine stress tissue Doppler echocardiography prior to coronary angiography. This color tissue Doppler database was analyzed for IVA in 1192 basal and mid segments at rest and again at peak stress. Angiographic findings were compared to IVA and peak systolic velocities (PSV) in corresponding cardiac segments. The diagnostic accuracy of IVA to predict coronary artery stenosis was determined using cut-off values for three representative segments and with the MYDISE diagnostic model including eight segments. Results: Regional IVA increased in a dose-dependent manner during dobutamine infusion. The response was blunted in the supply territory of stenosed coronary artery branches. IVA performed slightly better than PSV as single marker for coronary artery stenosis. A diagnostic model incorporating IVA and PSV was 85,95% accurate (area under receiver operating characterstic curves). Conclusions: Regional changes of isovolumic acceleration during dobutamine stress echocardiography reflect regional wall motion and can be used to predict coronary artery stenosis with similar accuracy as a model based on systolic myocardial velocities. As a single marker, IVA performed better than myocardial velocities. (ECHOCARDIOGRAPHY, Volume 22, November 2005) [source] Vasodilator Stress Induces Infrequent Wall Thickening Abnormalities Compared to Perfusion Defects in Mild-to-Moderate Coronary Artery Disease: Implications for the Choice of Imaging Modality with Vasodilator StressECHOCARDIOGRAPHY, Issue 4 2004M.R.C.P., Ph.D., Prem Soman M.D. Background: Experimental evidence suggests that although vasodilator stress agents consistently induce regional flow disparity between stenosed and normal coronary vascular beds, the occurrence of functional myocardial ischemia is infrequent, especially in mild-to-moderate coronary artery stenosis. Thus, it is hypothesized that dipyridamole infusion, even at high doses, will result in a disproportionately higher frequency of perfusion defects compared to regional wall thickening abnormalities. Methods: We performed simultaneous high-dose (0.84 mg/kg) dipyridamole stress echocardiography (Echo) and Tc-99m sestamibi SPECT (MIBI, methoxyisobutyl isonitrile) in 46 patients with coronary artery diameter stenosis >50% and ,90% in one or two epicardial coronary arteries, and no previous myocardial infarction. Results: Of a total of 828 segments, MIBI showed 97 reversible defects while Echo showed only 23 reversible wall thickening abnormalities. Of the 97 segments with reversible MIBI defects, only 13 (13%) showed simultaneous reversible wall thickening abnormalities during dipyridamole infusion. There were 24 patients with MIBI defects, of whom 10 (41%) showed a corresponding wall thickening abnormality. The sensitivity of MIBI and Echo for the detection of coronary artery disease was 52% and 21%, respectively (P = 0.001). Conclusion: This suggests that vasodilator stress is not optimally suited for use with techniques that use regional wall thickening abnormality as a marker of ischemia for the diagnosis of coronary artery disease. (ECHOCARDIOGRAPHY, Volume 21, May 2004) [source] Osteopontin as a novel prognostic marker in stable ischaemic heart disease: a 3-year follow-up studyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2010Panagiota Georgiadou Eur J Clin Invest 2010; 40 (4): 288,293 Abstract Objectives, Osteopontin (OPN) is a glycoprotein, which may play a major role in the regulation of biological phenomena. Increased levels of OPN have been linked to the presence and to the severity of atherosclerosis. This study was undertaken to assess the prognostic significance of plasma OPN levels in patients with stable ischaemic heart disease (IHD). Methods, In 101 patients with stable IHD and angiographically documented significant coronary artery stenosis, plasma OPN levels were measured at baseline (time of coronary arteriography). Patients were prospectively followed for a median time of 3 years (minimum 2·25, maximum 3·9 years). The primary study endpoint was the composite of cardiovascular death, non-fatal myocardial infarction, need for revascularization and hospitalization for cardiovascular reasons. Results, Baseline lnOPN levels were directly related to age (r = 0·27, P < 0·001) and inversely to left ventricular ejection fraction (r = ,0·32, P < 0·01). Left ventricular ejection fraction was an independent predictor of plasma OPN levels after adjustment for age and gender (, = ,0·013, P = 0·02). Median OPN value was 55 ng mL,1. In the univariate Cox-regression analysis, OPN levels > 55 ng mL,1 (n = 50) were significantly related to adverse cardiac outcome (HR = 2·40, 95% CI: 1·11,5·23, P = 0·027). In multivariate model, OPN levels > 55 ng mL,1 remained statistically significant independent predictor of adverse outcome after adjustment for age, gender, left ventricular ejection fraction and the number of diseased coronary arteries (HR = 2·88, 95% CI: 1·09,7·58, P = 0·032). Conclusion, OPN may provide significant prognostic information independent of other traditional prognostic markers in patients with stable IHD. [source] Predictors of coronary heart disease in Japanese patients with type 2 diabetes: Screening for coronary artery stenosis using multidetector computed tomographyJOURNAL OF DIABETES INVESTIGATION, Issue 1-2 2010Hiroko Nishioka Abstract Aims/Introduction:, Multidetector computed tomography (MDCT) coronary angiography has been applied as a tool for non-invasive evaluation of the coronary arteries. The purpose of the present study was to evaluate the effectiveness of MDCT in screening for coronary artery disease (CAD), and to identify the indications for screening in diabetes patients with CAD. Materials and Methods:, The study population consisted of 52 Japanese type 2 diabetes patients who underwent examination with a 64-slice MDCT scanner, electrocardiogram (ECG), echocardiography and ultrasonographic scanning of the carotid arteries. Regression analysis was carried out to assess the correlation between MDCT results and CAD risk factors. Results:, Stenosis of the coronary artery was detected in 19/52 patients. Of the 19 patients, 7 patients had no symptoms, including chest pain, and no ischemic changes in ECG. Significant differences between patients with stenosis and those without stenosis were detected by mean IMT (1.21 vs 0.95 mm), and duration of diabetes (20 vs 13 years). Two-tailed ,2 -test showed that a duration of diabetes of more than 20 years (odds ratio 6.222) and more than 1.1 mm of mean-IMT (odds ratio 4.600) significantly correlated with the stenosis. Conclusions:, It was shown that MDCT is useful in detecting coronary artery stenosis in diabetic patients without symptoms of CAD or ECG abnormality, and the predictors of CAD are mean IMT and duration of diabetes. It is recommended that patients with more than 1.1 mm mean IMT at the carotid artery and/or more than 20 years duration of diabetes should be screened for CAD by carrying out MDCT. [source] Assessment of regional myocardial oxygenation changes in the presence of coronary artery stenosis with balanced SSFP imaging at 3.0T: Theory and experimental evaluation in caninesJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2008Rohan Dharmakumar PhD Abstract Purpose To examine the dependence of steady-state free-precession (SSFP) -based myocardial blood-oxygen-level-dependent (BOLD) contrast on field strength using theoretical and experimental models. Materials and Methods Numerical simulations using a two-pool exchange model and a surgically prepared dog model were used to assess the SSFP-based myocardial BOLD signal changes at 1.5T and 3.0T. Experimental studies were performed in eight canines with pharmacological vasodilation under various levels of left circumflex coronary artery stenosis. Experimentally obtained BOLD signal changes were correlated against microsphere-based true flow changes. Results Theoretical results showed that, at 3.0T, relative to 1.5T, a threefold increase in oxygen sensitivity can be expected. Experimental studies in canines showed near similar results,a 2.5 ± 0.2-fold increase in BOLD sensitivity at 3.0T relative to 1.5T (P < 0.05). Based on the scatter gram of BOLD data and microsphere data, it was found that the minimum regional flow difference that can be detected with SSFP-based myocardial BOLD imaging at 1.5T and 3.0T were 2.9 and 1.6, respectively (P < 0.05). Conclusion This study demonstrated that SSFP-based myocardial BOLD sensitivity is substantially greater at 3.0T compared with 1.5T. The findings here suggest that SSFP-based myocardial BOLD imaging at 3.0T may have the necessary sensitivity to detect the clinically required minimum flow difference of 2.0. J. Magn. Reson. Imaging 2008;27:1037,1045. © 2008 Wiley-Liss, Inc. [source] Anti-beta 2 glycoprotein I antibodies and the risk of myocardial infarction in young premenopausal womenJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 12 2007P. L. MERONI Summary Background:,Contrasting data have been reported on the association between the presence of anti-phospholipid antibodies (aPL) and arterial thrombotic events, particularly those in coronary arteries. This discrepancy is perhaps related to the confounding effect of traditional risk factors. Among them, coronary atherosclerosis appears to be the most important in studies conducted in middle-aged and elderly patients.Objective:,To minimize such confounding effects, a multicenter case,control study on the association between aPL and myocardial infarction (MI) was carried out in a rare cohort of young premenopausal women.Methods:,We evaluated 172 cases hospitalized for a first MI before the age of 45 years and 172 controls individually matched with cases for age, sex and geographical origin. Clinical and laboratory data were collected and levels of anti-cardiolipin (aCL), anti-beta2 glycoprotein I (anti-,2GPI) and anti-nuclear antibodies (ANA) were measured.Results:,A significant association between MI and IgG/IgM anti-,2GPI antibodies was observed; the results were confirmed after adjusting for smoking and hypertension (anti-,2GPI IgG OR = 2.47, 95% CI 1.81,3.38; anti-,2GPI IgM 4th quartile OR 3.68, 95% CI 1.69,8.02). The association between anti-,2GPI antibodies and MI was detected in both subgroups with and without coronary artery stenosis. Whereas the association of aCL IgG with MI was modest, ANA showed no significant association with MI. No aPL were found in unselected patients (mainly males) who recently developed acute MI.Conclusions:,Anti-,2GPI antibodies are a significant risk factor for MI in young premenopausal women independently of other risk factors, including the degree of coronary artery stenosis. [source] Time-resolved flow measurement in the isolated rat heart: Characterization of left coronary artery stenosisMAGNETIC RESONANCE IN MEDICINE, Issue 3 2003Sascha Köhler Abstract The investigation of flow behavior in coronary arteries is of great importance for an understanding of heart failure and heart regulation mechanisms. The purpose of the present study was to demonstrate that flow velocity can be quantified in the coronary arteries of the isolated rat heart with high-resolution phase contrast MRI. A phase contrast cine-FLASH imaging sequence was used for flow quantification with an in-plane resolution of 70 ,m and a slice thickness of 500 ,m. With time-resolved measurements, coronary flow over the heart cycle was analyzed. Furthermore, the flow behavior in coronary stenosis was investigated and the degree of stenosis was quantified with MR phase contrast imaging. To achieve the required spatial resolution and a satisfactory signal-to-noise ratio, the experiments were performed at 11.75 T. Magn Reson Med 50:449,452, 2003. © 2003 Wiley-Liss, Inc. [source] Noninvasive Imaging of Angiogenesis Inhibition Following Nitric Oxide Synthase Blockade in the Ischemic Rat Heart in VivoMICROCIRCULATION, Issue 4 2005CHRISTIANE WALLER MD ABSTRACT Objective: Nitric oxide synthase inhibition has anti-angiogenic properties. Magnetic resonance (MR) imaging was used to image the functional significance of these microvascular changes in a rat model of chronic ischemic myocardium in vivo. Methods: The authors quantitatively determined myocardial perfusion and regional blood volume, left ventricular geometry, and function using MR imaging. Animals received either L-NAME + hydralazine or no treatment and were investigated 1 and 2 weeks after induction of coronary artery stenosis or sham operation at rest and during vasodilatation. Double-labeling immunohistochemistry was used to visualize angiogenesis and to compare with data obtained by MR imaging. Results: Left ventricular mass and end-diastolic volumes were comparable in both groups 2 weeks after treatment. However, basal and maximum perfusion in animals with L -NAME + hydralazine treatment were reduced compared to animals not treated (p < .05). Basal regional blood volume remained constant in all groups, whereas maximum regional blood volume was reduced by L -NAME + hydralazine (p < .05). Endothelial cell proliferation, a direct marker for angiogenesis, was reduced by L -NAME + hydralazine (p < .01). Conclusions: MR imaging allows noninvasive quantification of functional microcirculation and angiogenesis in the rat heart in vivo. Nitric oxide synthase blockade results in changes in functional microcirculation and in an inhibition of angiogenesis in both ischemic and nonischemic myocardial tissue. [source] Cryoablation of Accessory Pathways in ChildrenPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2007VOLKAN TUZCU M.D. Background: Cryoablation is utilized for septal tachycardia substrates due its safety. Considering the recent studies which reveal coronary artery stenosis related to radiofrequency ablation (RFA) in children, cryoablation may offer advantages for nonseptal accessory pathways (APs) as well. The aim of this study was to investigate the efficacy and safety of cryoablation of APs in children. Methods: A total of 39 patients (median age = 9.3 years, range 4.8 to 17.2 years) underwent cryoablation of APs. A three-dimensional, surface electrode-based navigation system (EnSite NavXÔ, St.Jude Medical Inc., St. Paul, MN, USA) is used to decrease the fluoroscopy exposure. Results: A total of 45 APs were identified. Of these APs, 23 were septal (anteroseptal, midseptal, posteroseptal) and 22 were nonseptal. Acute success rate with cryoablation was 73%. RFA was used when cryoablation failed and overall acute success rate was 84%. To assess for the effect of institutional experience, the initial 23 APs were compared to the recent 22 APs and acute success rate revealed significant improvement (57% vs. 91%). Recurrence rate was 24% during a median follow-up of 282 days. Conclusion: Cryoablation of APs is safe and yields to high acute success rates in children. It can potentially be used as the first ablation option for all APs in children. However, recurrence rate is higher compared to the RFA and there is a need for prospective comparative studies. [source] The association between effort,reward imbalance and coronary atherosclerosis in a Chinese sampleAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2010Weixian Xu MD Abstract Background Previous studies of job strain and coronary heart disease (CHD) have produced mixed findings. We aimed to examine the association between job stress evaluated by the effort,reward imbalance (ERI) model and coronary atherosclerosis assessed by coronary angiography in a Chinese sample. Methods Three-hundred twenty participants accepting coronary angiography for the first time were enrolled in series. Job stressors were evaluated by the ERI model. The presence and severity of CHD were assessed by measuring the coronary artery stenosis (the presence of >50% luminal stenosis in one or more major coronary arteries). The association between job stressors and CHD was examined by multivariate analysis. Results Compared with the low-level group, high-level effort, overcommitment, and ERI increased CHD risk with odds ratio (OR) 2.5 (95% confidence interval (CI): 1.2,5.0), 2.5 (95% CI: 1.2,5.0), 2.4 (95% CI: 1.2,4.9), respectively, after adjustment for confounders. They were also significantly positively correlated with the complexity of coronary artery lesions, respectively. Dose,response relationships were observed. Conclusions ERI was associated with coronary artery lesions in a sample of Chinese workers. Longitudinal research and interventional designs are needed to confirm the mechanism and to provide evidence for the prevention of CHD. Am. J. Ind. Med. 53:655,661, 2010. © 2010 Wiley-Liss, Inc. [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] Characteristics of patients with abnormal stress technetium Tc 99m sestamibi SPECT studies without significant coronary artery diameter stenosesCLINICAL CARDIOLOGY, Issue 11 2003Peter Ammann M.D. Abstract Background: Single-photon emission computed tomography (SPECT) sestamibi (MIBI) is an excellent tool for detection of coronary artery disease (CAD), preoperative risk assessment, and follow-up management after coronary revas-cularization. While the sensitivity of MIBI SPECT for detecting CAD has been reported to exceed 90%, the specificity ranges between 53,100%. Hypothesis: The study was undertaken to assess characteristics of patients with abnormal stress technetium Tc 99m sestamibi SPECT (MIBI) studies without significant coronary artery diameter stenoses (< 50%). Methods: Between January 1999 and November 2000, 270 consecutive patients were referred for coronary angiography due to reversible MIBI uptake defects during exercise. In 41 patients (15%; 39% women, mean age 59 ± 9 years), reversible MIBI uptake defects were assessed although coronary angiography showed no significant CAD. These patients were compared with age- and gender-matched patients with perfusion abnormalities (39% women, mean age 60 ± 9 years), due to significant CAD (coronary artery stenosis > 50%). Results: There were no significant differences between the two groups regarding body mass index, left bundle-branch block (LBBB), or method of stress test (dipyridamole in patients with LBBB or physical inactivity [n= 11] and exercise in all the others [n= 30]). Left ventricular hypertrophy (44 vs. 23%, p = 0.05) and left anterior fascicularblock (LAFB) (17 vs. 0%, p = 0.005) were more common in patients with perfusion abnormalities with no significant CAD, whereas ST-segment depression during exercise (17 vs. 37% p = 0.05) and angina during exercise (15 vs. 29%, p = 0.02) were significantly less common than in patients with abnormal MIBI perfusion studies and angiographically significant CAD. Sestamibi uptake defects during exercise were significantly smaller in patients without significant CAD than in matched controls with significant CAD (p < 0.0004). Conclusion: Of 270 consecutive patients, 41 (15%) referred to coronary angiography due to reversible MIBI uptake defects showed coronary artery stenoses <50%. Twenty-six (10%) of these presented angiographically normal coronary arteries. The significantly higher proportion of left ventricular hypertrophy and LAFB in patients with reversible MIBI uptake defects without significant CAD suggest microvascular disease, angiographically underestimated CAD, and conduction abnormalities as underlying mechanisms. [source] Validation of a screening protocol for identifying low-risk candidates with type 1 diabetes mellitus for kidney with or without pancreas transplantationCLINICAL TRANSPLANTATION, Issue 2 2006Irene W.Y. Ma Abstract: Background: Certain clinical risk factors are associated with significant coronary artery disease in kidney transplant candidates with diabetes mellitus. We sought to validate the use of a clinical algorithm in predicting post-transplantation mortality in patients with type 1 diabetes. We also examined the prevalence of significant coronary lesions in high-risk transplant candidates. Methods: All patients with type 1 diabetes evaluated between 1991 and 2001 for kidney with/without pancreas transplantation were classified as high-risk based on the presence of any of the following risk factors: age ,45 yr, smoking history ,5 pack years, diabetes duration ,25 yr or any ST,T segment abnormalities on electrocardiogram. Remaining patients were considered low risk. All high-risk candidates were advised to undergo coronary angiography. The primary outcome of interest was all-cause mortality post-transplantation. Results: Eighty-four high-risk and 42 low-risk patients were identified. Significant coronary artery stenosis was detected in 31 high-risk candidates. Mean arterial pressure was a significant predictor of coronary stenosis (odds ratio 1.68; 95% confidence interval 1.14,2.46), adjusted for age, sex and duration of diabetes. In 75 candidates who underwent transplantation with median follow-up of 47 months, the use of clinical risk factors predicted all eight deaths. No deaths occurred in low-risk patients. A significant mortality difference was noted between the two risk groups (p=0.03). Conclusions: This clinical algorithm can identify patients with type 1 diabetes at risk for mortality after kidney with/without pancreas transplant. Patients without clinical risk factors can safely undergo transplantation without further cardiac evaluation. [source] | ||||||||||||||||||||||