Influence of diabetes mellitus on diagnostic potential of iodine-123-BMIPP imaging for coronary artery stenosis in hemodialysis patients

BACKGROUND: Single-photon emission computed tomography (SPECT) using a fatty acid analogue, iodine-123-beta-methyl iodophenyl-pentadecanoic acid (123I-BMIPP), as a tracer may be effective for detecting coronary artery disease in end-stage renal disease (ESRD) patients. In this study, we investigated whether the presence of diabetes mellitus may affect the diagnostic potential of BMIPP SPECT for detecting coronary stenosis in ESRD patients. METHODS: 123I-BMIPP SPECT was performed in 98 diabetic hemodialysis patients (male to female ratio 66:32; mean age 63.6+/-9.8 years) and 103 nondiabetic hemodialysis patients (68:35; 64.5+/-10.4 years), followed by coronary angiography within 60 days of the SPECT. SPECT imaging was evaluated and graded on a 5-point scale (0=normal, 4=absence of tracer) and assessed as a BMIPP summed score for 17 left ventricular segments. RESULTS: Coronary angiography revealed that 72.4% (71/98) of the diabetic patients and 56.3% (58/103) of the non-diabetic patients had significant coronary stenosis more than 50%; incidences of asymptomatic coronary stenosis were 77.5% in diabetic patients and 72.4% in nondiabetic patients. When a BMIPP summed score of 8 or more was defined as abnormal, sensitivity, specificity and accuracy for detecting coronary stenosis by BMIPP SPECT were 97.2, 63.0 and 87.8% in diabetic patients, and 96.6, 73.3 and 86.4% in nondiabetic patients. In receiver operating characteristic analysis, the areas under the curve of BMIPP SPECT to diagnose coronary stenosis were 0.897 in diabetic and 0.906 in nondiabetic patients. CONCLUSIONS: BMIPP SPECT seems to be able to detect coronary stenosis in diabetic as well as nondiabetic hemodialysis patients.     

Insulin resistance and impaired myocardial fatty acid metabolism in dialysis patients with normal coronary arteries

We investigated whether insulin resistance is associated with impaired cardiac fatty acid metabolism in maintenance hemodialysis patients without coronary artery disease. We studied 55 nondiabetic (63+/-11 years old) and 51 diabetic (61+/-10 years old) hemodialysis patients with normal coronary arteries, using single-photon emission computed tomography (SPECT) with an iodinated fatty acid analogue, iodine-123-beta-methyl iodophenyl-pentadecanoic acid ((123)I-BMIPP), to evaluate cardiac fatty acid metabolism. SPECT imaging was graded regionally from 0 (normal) to 4 (absence of tracer) to calculate a summed score for 17 left ventricular segments. Insulin resistance was determined using the homeostasis model assessment index of insulin resistance (HOMA-IR). HOMA-IR correlated with summed BMIPP score in nondiabetic and diabetic patients. Stepwise multiple regression analysis showed that HOMA-IR was independently associated with BMIPP summed score in nondiabetic (beta=0.774, t=9.218, P=0.0001) and diabetic patients (beta=0.792, t=9.079, P=0.0001). Left ventricular ejection fraction was lower in nondiabetic subjects with BMIPP summed score of at least 6 plus HOMA-IR of at least 4 than in others with lower values for both assessments (53.1+/-13.8%, n=20 vs 67.7+/-9.1%, n=23, P=0.0002); this was also true in diabetic subjects (50.9+/-15.2%, n=24 vs 71.0+/-13.6%, n=11, P=0.0007). Association between insulin resistance and impaired cardiac fatty acid metabolism may contribute to left ventricular dysfunction in patients with maintenance hemodialysis without coronary diseases.     

Risk stratification for cardiac death in hemodialysis patients without obstructive coronary artery disease

The incidence of cardiac death is higher among patients receiving dialysis compared with the general population. Although obstructive coronary artery disease is involved in cardiac deaths in the general population, deaths in hemodialysis patients occur in the apparent absence of obstructive coronary artery disease. To study this further, we prospectively enrolled 155 patients receiving hemodialysis after angiography had confirmed the absence of obstructive coronary lesions. All patients were examined by single-photon emission computed tomography using the iodinated fatty acid analog, BMIPP, the uptake of which was graded in 17 standard myocardial segments and assessed as summed scores. Insulin resistance was determined using the homeostasis model assessment index of insulin resistance (HOMA-IR). During a mean follow-up of 5.1 years, 42 patients died of cardiac events. Stepwise Cox hazard analysis associated cardiac death with reduced BMIPP uptake and increased insulin resistance. Patients were assigned to subgroups based on BMIPP summed scores and HOMA-IR cutoff values for cardiac death of 12 and 5.1, respectively, determined by receiver operating characteristic analysis. Cardiac death-free survival rates at 5 years were the lowest (32.2%) in the subgroup with both a summed score and assessment equal to or above the cutoff values compared with any other combination (52.9-98.7%) above, equal to, or below the thresholds. Thus, impaired myocardial fatty acid metabolism and insulin resistance may be associated with cardiac death among hemodialysis patients without obstructive coronary artery disease.     

Myocardial fatty acid imaging identifies a group of hemodialysis patients at high risk for cardiac death after coronary revascularization

We prospectively evaluated if impaired myocardial fatty acid metabolism is involved in cardiac death after revascularization by percutaneous coronary artery intervention in dialysis patients. A cohort of hemodialysis patients was assessed by dual single-photon emission computed tomography using the radioiodinated fatty acid analogue BMIPP and radiolabeled thallium chloride. Tomography was done within one month before the first coronary intervention and at the last follow-up angiography at which neither restenosis nor de novo lesions were detected. Radiolabel uptake on tomography images was graded in segments and calculated as summed BMIPP or thallium scores. Among the 90 hemodialysis patients in the study, 19 died of cardiac events. Multivariate Cox hazard analysis found a significant association of cardiac death with the BMIPP summed scores at the last follow-up angiography. Kaplan-Meier analysis showed the cardiac death-free survival rates at 3 years of follow-up were significantly higher in patients with lower BMIPP summed scores. These results suggest that myocardial fatty acid imaging may be a useful test to identify high risk groups of cardiac death in hemodialysis patients.     

Diagnostic and prognostic value of dobutamine thallium-201 single-photon emission computed tomography after heart transplantation.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is a major cause of mortality in heart transplant recipients. We investigated the diagnostic and prognostic value of dobutamine thallium-201 ((201)Tl) single-photon emission computed tomography (SPECT) in heart transplant recipients. METHODS: We studied 47 patients (age 51.6 +/- 11.7 years, 37 men), at a mean of 34.0 +/- 21.4 months after heart transplant, who received dobutamine (201)Tl SPECT, echocardiography and coronary angiography within 1 month of each other. SPECT was considered abnormal in the presence of reversible or fixed defects in >/=2 segments. Significant CAV was defined as >/=50% luminal stenosis. RESULTS: Coronary angiograms were normal in 37 patients. Non-significant CAV was detected in 1 patient and significant CAV in 9 patients. The sensitivity, specificity, positive predictive value and negative predictive value of SPECT for the detection of significant angiographic CAV were 89%, 71%, 42% and 96%, respectively. Large reversible perfusion defects (>/=6 segments) always indicated significant CAV. In patients with normal left ventricular function, a lung/heart ratio (LHR) of >/=0.37 during stress was also an independent predictor of significant CAV (odds ratio 15.5, p = 0.04). A higher stress LHR was associated with greater vessel involvement (r = 0.516, p = 0.0002). Patients with impaired left ventricular function also had higher stress and resting LHR. Over 40.3 +/- 21.9 months after the first SPECT, 1 patient developed significant angiographic CAV and another 4 had cardiac death. Large reversible perfusion defect was a significant predictor of cardiac death (p = 0.002). CONCLUSIONS: Dobutamine (201)Tl SPECT is a useful method for detecting patients with significant CAV and assessing prognosis. It is reasonable and safe to design individualized surveillance intensity of coronary angiography for post-transplant patients on the basis of non-invasive monitoring of dobutamine (201)Tl testing.     

Close association of Chlamydia pneumoniae IgA seropositivity by ELISA with the presence of coronary artery stenosis in haemodialysis patients.

BACKGROUND: Traditional risk factors of cardiovascular disease do not fully explain the accelerated atherosclerosis present in patients with end-stage renal disease (ESRD). The goal of this study was to identify the association of clinical and laboratory factors including seropositivity for Chlamydia pneumoniae determined by a specific enzyme-linked immunosorbent assay (ELISA) with the presence of coronary artery disease identified by coronary angiography in ESRD patients. METHODS: We prospectively enrolled 161 consecutive ESRD patients undergoing haemodialysis for >6 months (106 men, 55 women; mean age 63.1+/-10.2 years; mean dialysis duration 91.3+/-90.1 months). All patients underwent coronary angiography within 1 week after blood sampling. The associations of coronary artery disease with clinical parameters including C. pneumoniae IgA and IgG seropositivity were analysed using multiple logistic regression models. RESULTS: Coronary stenosis >50% was found in 102 of 161 haemodialysis patients (63.4%). Of the 102 patients, 75.5% were asymptomatic. Seropositivity for C. pneumoniae IgA was found in patients with coronary stenosis (77 out of 102, 75.5%) more frequently (P<0.001) than in patients without coronary stenosis (10 out of 59, 16.9%). Seropositivity for C. pneumoniae IgA but not IgG was strongly associated with the presence of coronary stenosis in multiple logistic regression analysis (odds ratio, 18.440; 95% confidence interval, 7.500-45.337), independently of the Framingham coronary risk factors, factors peculiar to ESRD or serum C-reactive protein levels. CONCLUSIONS: C. pneumoniae IgA seropositivity determined by ELISA is an independent laboratory factor indicating the presence of coronary artery stenosis in ESRD patients undergoing maintenance haemodialysis.     

Predicting cardiac events with Tl201 dipyridamole myocardial scintigraphy in renal transplant recipients

BACKGROUND: Renal transplant recipients should be screened for coronary artery disease. The purpose of this study was to evaluate the usefulness of thallium-201 dipyridamole myocardial perfusion single-photon emission computed tomography (SPECT) to predict major cardiac events in these patients. METHODS AND RESULTS: Eighty-two consecutive patients (61 males) in hemodialysis (HD) treatment, awaiting renal transplantation, underwent dipyridamole Tl-201 SPECT for pretransplant risk stratification. SPECT semiquantitative analysis showed a normal perfusion pattern in 52 patients (group A) and fixed defects in 9 (group B). Reversible perfusion defects were found in 21 (group C). Cardiac death, myocadial infarction, and unstable angina were sought as cardiac events. During a follow-up lasting 28.3 +/- 21.6 months, three patients of group A died for a non-cardiac cause. In group C, six patients (28.6%) had a cadiac event: one had a non-q wave myocardial infarction after renal transplantation; five were admitted with unstable angina. No cardiac events were observed in groups A and B (p = 0.0001). SPECT semiquantitative analysis showed that a summed difference score > or = 3 significantly increased the risk of cardiac events (odds ratio 4.5, C.I. 2.5-8.1). CONCLUSION: Cardiac events were only observed in HD patients with Tl-201 SPECT dipyridamole reversible defects (group C). A normal pattern or a fixed defect in Tl-201 dipyridamole SPECT in HD patients identified a good long-term prognosis.     

Use of multidetector computed tomography for evaluating coronary artery disease in patients undergoing dialysis

Aim: Cardiovascular disease is the most common cause of death in patients undergoing dialysis. The accuracy of multidetector computed tomography (MDCT) for detecting coronary disease has not been determined, and little information is available regarding the performance of MDCT in patients undergoing dialysis. Methods: Twenty‐nine patients undergoing dialysis were analyzed and MDCT and coronary angiography (CAng) were performed consecutively. The coronary arteries were divided into four segments for analysis. We compared the significant stenosis lesions (≥50% luminal narrowing) identified by MDCT with those found by CAng. The total coronary artery calcium (CAC) score was determined by summing the individual lesion scores from each of the coronary branches. Results: One hundred and sixteen coronary artery branches in 29 patients were analyzed. The sensitivity, specificity, and positive and negative predictive values of MDCT for detecting significant coronary artery stenosis (≥50% stenosis) were 68%, 94%, 71% and 93%, respectively. The CAC scores were significantly higher in subjects with coronary artery disease (CAD) (514.0 ± 493.6 vs 254.3 ± 375.3, P = 0.05). The severe CAC score (>500) was related to the presence of significant CAD (P = 0.05) and the sensitivity and specificity for detecting significant CAD were 50% and 80%, respectively. Conclusion: MDCT is a useful and non‐invasive approach for detecting or excluding CAD in patients undergoing dialysis.     

The influence of coronary artery disease and bypass grafting on early and late survival after valve replacement for aortic stenosis

The influence of coronary artery disease and bypass grafting on survival after valve replacement for aortic stenosis (1975 to 1986, N = 512) was analyzed. Mean follow-up for 30-day survivors was 5.1 years (0.1 to 12.9 years). A total of 205 patients had coronary angiography performed: 122 did not have coronary artery disease, 55 with coronary artery disease underwent bypass grafting, and 28 with coronary artery disease did not. Early mortality rates (less than or equal to 30 days)/5-year cumulative survivals (standard error) were 4.1%/86% (4%), 3.6%/68% (8%), and 17.9%/51% (13%), respectively (p less than 0.05/p less than 0.01). Triple vessel/left main stem disease was more prevalent in patients with coronary disease who underwent bypass grafting (47%) than in those who did not (14%; p less than 0.05). Multivariate analysis revealed that right ventricular failure and omission of bypass grafting in patients with coronary artery disease were independent determinants of early mortality. A Cox regression analysis identified coronary artery disease and aortic valve gradient as determinants of mortality after hospital dismissal, which was not influenced by bypass grafting. On the basis of a coronary artery disease score (positive predictive value for coronary artery disease of 66%) developed on the patients with angiography, 307 patients without angiography were divided into 234 with a low score and 73 with a high score. Early mortality rates/5-year survivals (standard error) were 6.4%/86% (2%) and 16.4%/67% (6%), respectively (p less than 0.01/p less than 0.001). Autopsy revealed stenotic or occlusive coronary artery disease in 92% of 12 early deaths in the group with a high coronary artery disease score and in 33% of 15 in the group with a low score (p less than 0.01). Left ventricular failure and a high coronary artery disease score were independent determinants of early mortality, whereas cardiothoracic index, a high coronary artery disease score, and left ventricular failure were independent predictors of death after hospital dismissal. Despite more severe coronary artery disease, bypass grafting reduced early mortality to a level comparable with that of patients without coronary artery disease, contrasting with a high early mortality rate for unbypassed coronary artery disease. Coronary artery disease increased the late mortality rate, which was not modified by bypass grafting. In the group without angiography, undiagnosed and unbypassed coronary artery disease probably increased both early and late mortality. Coronary angiography should be performed in all adult patients with aortic stenosis, and those with significant coronary artery disease should undergo bypass grafting concomitant with valve replacement.     

终末期肾病患者心血管事件与血清胎球蛋白A及冠脉钙化的关系

目的探讨终末期肾病（ESRD）患者心血管事件发生与血清胎球蛋白A及冠脉钙化的关系。方法对38例ESRD初始血液透析患者进行血清胎球蛋白A及相关因素检测，对其中的29例患者进行冠状动脉多层螺旋CT钙化评价研究。所有38例患者随访时间为18个月。22例非ESRD慢性肾脏病（CKDⅡ～Ⅲ期）患者人选对照组。结果38例ESRD初始透析患者在18个月随访期内出现心血管事件30例次，因心血管事件死亡者6例，占15．79％，而非ESRD患者心血管事件仅3例次（P〈0．01）且无一例死亡（P〈0．05）。ESRD血清低胎球蛋白A组心血管事件显著高于ESRD血清高胎球蛋白A组（P〈0．01）。多元逐步回归分析显示，心血管事件与血清胎球蛋白A（P〈0．01）、C反应蛋白（CRP）（P=0．0014）及低密度脂蛋白C（LDL-C）（P=0．008）密切相关。18／29例（62．07％）有冠状动脉钙化。冠状动脉钙化患者心血管事件比无冠状动脉钙化患者显著增多（P〈0．01）。冠脉钙化的ESRD患者血清胎球蛋白A水平较无冠脉钙化的ESRD患者明显下降（P〈0．01）。冠脉钙化与胎球蛋白A下降及高血磷有关（P〈0．01，P〈0．01）。结论ESRD透析患者心血管事件和（或）心血管事件死亡可能与血清胎球蛋白A下降及冠状动脉钙化有关。     

ADENOSINE THALLIUM-201 SCANS IN PATIENTS UNDERGOING ELECTIVE NON-CARDIAC SURGERY

Dipyridamole Thallium-201 (²⁰¹Tl) scintigraphy has been used widely for assessment of patients prior to vascular surgery. Recently, Adenosine has been reported to be a safe and useful alternative to Dipyridamole. The purposes of this study were to evaluate the safety and feasibility of the use of Adenosine, to evaluate the correlation of Adenosine ²⁰¹Tl scans with coronary angiograms (when available) and to evaluate the effect of scan results on clinician management style. Fifty adults with abdominal aortic aneurysm or other vascular disease underwent an intravenous infusion of Adenosine in conjunction with initial and delayed planar ²⁰¹Tl scans. Images were interpreted qualitatively and quantitatively by the consensus of two or more experienced observers with patients showing transient left ventricular dilatation or redistribution in one or more myocardial segments reported as being at high risk of peri-operative cardiac events. Of the 50 subjects studied, 49 tolerated the maximum infusion dose with 60% experiencing minor transient symptoms. Low (n= 30) and high risk (n= 20) patients were defined according to Adenosine ²⁰¹Tl scans. Age, gender and clinical characteristics were similar in both groups. Thirteen (65%) high risk subjects had coronary angiography compared with only three (10%) low risk patients. Patients with high-risk ²⁰¹TI scans were also more likely to proceed to coronary revascularization prior to non-cardiac surgery [5/20 (25%) vs 1/30 (3%)]. The positive predictive value of high risk ²⁰¹Tl scans for coronary artery disease was 85%. Thus, Adenosine is considered a useful and safe alternative to Dipyridamole. In conjunction with ²⁰¹Tl scintigraphy Adenosine has the potential to modify management of patients prior to elective non-cardiac surgery and may reduce adverse peri-operative cardiac events.     

Extent and Severity of Coronary Disease and Mortality in Patients with End-Stage Renal Failure Evaluated for Renal Transplantation

The purpose of this study is to explore the relationship between coronary artery disease (CAD), transplantation status and subsequent mortality in end-stage renal disease (ESRD) patients undergoing evaluation for renal transplantation. Two hundred fifty-three ESRD patients at high risk for CAD underwent coronary angiography as part of a renal transplant evaluation. The cohort was divided into three groups: Group 1 (n = 127) had no vessels with ≥50% stenosis, Group 2 (n = 56) had one vessel with ≥50% stenosis and Group 3 (n = 70) had two or more vessels with ≥50% stenosis. Long-term survival was determined; median follow-up was 3.3 years. The baseline characteristics were similar except for older age and higher proportion of diabetes mellitus, dyslipidemia and peripheral vascular disease in Groups 2 and 3 patients as compared to Group 1. Survival was worse in Group 3 compared to Group 1 (p < 0.0001). Each of the three subgroups had better survival with renal transplantation than those who did not undergo transplantation (p < 0.0001). Although the degree of CAD is related to subsequent mortality, transplantation is associated with better survival regardless of the extent and severity of CAD. Thus, the presence of CAD should not exclude ESRD patients from consideration for this therapy.     

A comparison of intravascular ultrasound with coronary angiography for evaluation of transplant coronary disease in pediatric heart transplant recipients.

BACKGROUND: The purpose of this study was to assess the sensitivity of coronary angiography versus intravascular ultrasound for detecting significant transplant coronary artery disease in children. We also examined associations between potential risk factors for transplant coronary artery disease and intravascular ultrasound findings, and evaluated the safety of intravascular ultrasound. METHODS: All pediatric heart transplant patients who had intravascular ultrasound following routine coronary angiography were included. Transplant coronary artery disease was quantified by assigning Stanford classes and calculating intimal indices for intravascular ultrasound images. These findings were compared with qualitative coronary angiography findings. Risk factors for transplant coronary artery disease, cardiac events and complications were recorded. RESULTS: Sixteen patients had 27 intravascular ultrasound procedures during the study period. All patients had evidence of transplant coronary artery disease at their latest intravascular ultrasound study. Of the patients whose most severely afflicted coronary artery underwent both imaging modalities at the latest study, 50% had significant transplant coronary artery disease (Stanford Class >/=II) by intravascular ultrasound and normal coronary angiography. A higher mean first-year biopsy score may be associated with significant transplant coronary artery disease by intravascular ultrasound, but a large number of patients will be required to determine this with statistical certainty. One major complication occurred early in the experience. CONCLUSIONS: In children, intravascular ultrasound is more sensitive for detecting significant transplant coronary artery disease than coronary angiography, but may add cost, time and potential morbidity to screening protocols. Prospective, multicenter studies are needed to best utilize intravascular ultrasound in this patient population.     

Percutaneous coronary intervention in patients with end-stage renal disease

Patients with end-stage renal disease (ESRD) represent a growing number of patients in the cardiac catheterization laboratories worldwide. This is a consequence of the growing absolute number of ESRD patients in developed countries, better noninvasive diagnostic tools, better catheterization facilities and last-but-not-least better education of referring physicians about the incidence and prognosis of coronary artery disease (CAD) for patients with ESRD. There is growing evidence of the positive impact of coronary revascularization on long-term outcome of these patients. ESRD patients have a high comorbidity and are therefore better candidates for the less invasive approach using percutaneous coronary intervention (PCI) rather than coronary artery bypass surgery (CABG). From the view of the interventional cardiologist, ESRD patients represent one of the most challenging patient cohort concerning technical challenges and potential risk of complication for the patient. Percutaneous coronary intervention (PCI) including debulking techniques and stent implantation is the current standard therapy for patients with symptomatic single-vessel disease (SVD) and the preferred therapy for most patients with focal, polyfocal or even diffuse multi-vessel disease (MVD). Coronary bypass surgery is reserved for a decreasing number of patients with mechanically untreatable coronary lesions and unprotected left main stem stenosis. The problem of restenosis and subsequent target lesion revascularization has been decreased to a minimum by the use of drug-eluting stents (DES), even though prospective randomized trials including ESRD patients are lacking. In case of acute coronary syndromes, the need for immediate coronary angiography and subsequent revascularization by means of PCI should be pointed out.     

Prognostic value of stress myocardial perfusion imaging using adenosine triphosphate at the beginning of haemodialysis treatment in patients with end-stage renal disease

Background. Non-invasive detection of coronary artery disease(CAD) remains difficult in patients with end-stage renal disease(ESRD). This study evaluated the ability of pharmacologic stressmyocardial perfusion imaging to predict cardiac events in patientswith ESRD. Methods. A prospective study was carried out in 49 consecutivepatients with ESRD. Thallium-201 single photon emission computedtomography (SPECT) using high-dose adenosine triphosphate (ATP)was performed within 1 month of the beginning of haemodialysis.The study end-point was a cardiac event or the 1-year anniversaryof the SPECT study. Results. Twenty-four patients (17 diabetics, 57% and seven non-diabetics,37%) had myocardial perfusion defects. The remaining 25 patientshad normal perfusion images. Fifteen patients had non-fatalcardiac events and two patients died of a cardiac cause. Allpatients who had non-fatal cardiac events underwent myocardialrevascularization and survived until the end of follow-up. The1-year cardiac event-free survival rate was 34% among patientswith perfusion defects and 96% among patients without perfusiondefects (P<0.001). The presence of a myocardial perfusiondefect was the only independent predictor of 1-year cardiacevents both in overall (HR, 49.91; 95% CI, 5.15–484.00;P<0.001) and in diabetic patients (HR, 33.72; 95% CI, 2.96–383.5;P = 0.005). Diabetes and an increased C-reactive protein wereassociated with the progression of CAD. Conclusions. Normal myocardial perfusion imaging by stress thallium-201SPECT using high-dose ATP performed within 1 month after thebeginning of haemodialysis treatment is a powerful predictorof cardiac event-free survival in patients with ESRD.     

Myocardial perfusion scintigraphy as a screening method for significant coronary artery stenosis in cardiac transplant recipients.

BACKGROUND: Several studies have explored the feasibility of using myocardial perfusion imaging to detect allograft vasculopathy after heart transplantation. We undertook the present prospective consecutive study to comparatively evaluate the role of serial myocardial perfusion single-photon emission computed tomography (SPECT) scanning and coronary arteriography (CAG) in detecting coronary artery stenosis suitable for coronary angioplasty in heart transplant recipients. METHODS: Within a 2-week interval during a follow-up period of 5.6 (95% confidence limits 2.1 to 12) years, 255 serial CAGs and myocardial perfusion scintigraphies were performed in 67 patients. Arteriography and scintigraphy were performed once yearly after heart transplantation. We retrospectively analyzed the data. RESULTS: Myocardial scintigraphy showed pathologic reversible defects in 9 out of 67 patients. Four of these patients had significant (>50% and also >70%) focal segmental stenosis in the middle and proximal parts of the coronary arteries (Type A lesions), 1 had diffuse and circumferential narrowing in the distal parts (Type B lesions), whereas CAG showed no lesions in the remaining 4 patients. The patients with significant Type A lesions were revascularized with percutaneous coronary angioplasty. Coronary arteriography showed that 1 patient had extensive Type A and Type B lesions, whereas myocardial perfusion scans detected no. The predictive value of a negative (normal) SPECT was 98% (95% confidence limits 94% to 100%) for the detection of lesions suited for revascularization. CONCLUSIONS: Annual myocardial SPECT seems well suited to screen for significant coronary artery stenosis. A SPECT study without reversible defects virtually excludes lesions suitable for coronary artery revascularization.     

Coronary heart disease extension as a predictor of atherosclerotic renal artery stenosis

BACKGROUND: Although the association of renal artery stenosis with coronary artery disease is well established, the best cutoff of diseased coronary vessels predicting atherosclerotic narrowing of renal artery remains still undefined. METHODS: In 109 consecutive patients (78/31 M/F) submitted to elective coronary angiography because of effort angina, renal angiography was also performed in the same session. We considered only renal artery stenosis > or =60% to be of clinical relevance. RESULTS: Coronary artery stenosis was present in 87 patients (80%), while significant narrowing of renal arteries was found in 42 patients (39%). On univariate analysis, the odds ratio (OR) of renal artery stenosis associated with 1 stenotic coronary vessel was 1.76 (95% confidence interval [95% CI], 1.34-2.33, p<0.001). This estimate was confirmed in a multiple logistic regression model adjusting for a series of potential confounders (OR=1.83, 95% CI, 1.34-2.48, p<0.001). On receiver operating characteristic curve analysis (area under the curve: 0.74 +/- 0.05, p<0.001), the presence of 3 diseased coronary vessels provided the best cutoff for the diagnosis of concomitant renal artery stenosis (positive predictive value: 63%; negative predictive value: 76%). CONCLUSIONS: There is a strong parallelism between the number of diseased coronary vessels and the occurrence of renal vascular disease. The presence of 3 diseased coronary vessels may corroborate the decision of performing renal angiography in patients with ischemic heart disease.     

Is incidental renal arteriography justified in a population of patients with symptomatic peripheral arterial disease?

Renal artery stenosis is a consequence of generalized atherosclerosis and many specialists perform routine selective renal angiography to detect and treat renal artery stenosis. The incidence of clinically important renal artery stenosis is not well defined in patients with symptomatic peripheral arterial disease. The purpose of this study was to better delineate the incidence of and the risk factors associated with renal artery stenosis, renovascular hypertension, and ischemic nephropathy incidentally discovered during angiography for symptomatic peripheral arterial disease. Two hundred consecutive patients undergoing angiographic evaluation of symptomatic lower extremity peripheral arterial disease were studied retrospectively. Angiograms were reviewed for the presence of renal artery stenosis (defined as >or= 25% diameter reduction in either renal artery) and findings were then correlated to the clinical diagnosis of renovascular hypertension (> 50% renal artery stenosis and >or= 3-drug resistive hypertension) and ischemic nephropathy (defined as > 50% bilateral renal artery stenosis, 3-drug hypertension, and creatinine >or= 1.5). Angiographic findings were also correlated with risk factors to determine if a relationship correlated to the presence of and degree of renal artery stenosis. Data were analyzed using the Student's t test, Chi-square model, and multiple logistic regression analysis. The overall incidence of any degree of renal artery stenosis in this study population was 26% (52 patients). Only 24 (12%) patients had an incidental finding of >or= 50% stenosis in either renal artery. Six (3%) of these patients were found to have associated renovascular hypertension. Additionally, 9 (4.5%) patients had coexistent renal insufficiency and significant renal artery stenosis; five with end-stage renal disease on chronic hemodialysis. Only one patient with end-stage renal disease had poorly controlled 3-drug hypertension. Thus definitive ischemic nephropathy was present in only one (0.5%) patient. Statistically significant risk factors associated with the presence of renal artery stenosis include hypertension (P < .001), coronary disease (P = .024), female gender (P = .010), diabetes (P = .039), aorto-iliac disease (P = .031), multiple levels of peripheral arterial disease (P < .001), and age over 60 ( P < .001). While the incidence of renal artery stenosis in patients being evaluated for symptomatic peripheral arterial disease is similar to that reported in the cardiology literature, the incidence of renovascular hypertension and ischemic nephropathy is exceedingly low (3% and 0.5%, respectively)-findings similar to data reported in the general hypertensive population. These data suggest that incidental selective renal angiography is not justified in patients with symptomatic peripheral arterial disease.     

126例血管造影患者动脉粥样硬化性肾动脉狭窄的临床分析

目的了解中老年冠心病患者动脉粥样硬化性肾动脉狭窄（ARAS）的发生率及探讨患者ARAS的相关因素。方法对126例确诊或疑诊冠心病的中老年患者行冠状动脉、肾动脉造影。以肾动脉狭窄（RAS）为因变量，临床因素为自变量，进行单变量Logistic回归分析。结果126例中24例有RAS,占19．04％；13例有明显RAS，占10．32％。24例RAS患者有28支狭窄肾动脉，狭窄位于肾动脉开El处为60．7％（17／28），肾动脉主干处为35．7％（10／28），分支处狭窄为3．57％（1／28）。64例确诊为冠状动脉粥样硬化患者中18例有肾动脉狭窄，ARAS的发生率为28．13％（18／64）；62例冠脉造影阴性患者有6例存在肾动脉狭窄，ARAS发生率为9．68％（6／62）。Logistic回归分析显示，冠脉病变、高脂血症、吸烟、肾功能不全与ARAS病变密切相关。结论在确诊或疑诊冠心病的中老年患者中，ARAS的发生率为19．04％；在确诊冠脉粥样硬化的患者中．ARAS的发生率明显高于冠脉造影阴性者。冠脉病变、高脂血症、吸烟、肾功能不全是ARAS的相关因素。     

Hemichorea due to hemodynamic ischemia associated with extracranial carotid artery stenosis. Report of two cases

In this paper the authors describe two patients with recurrent hemiparesis and limb shaking that gradually progressed to hemichorea. Cerebral angiography confirmed severe unilateral internal carotid artery stenosis (95%) contralateral to the hemichorea. The cerebral blood flow, assessed using N-isopropyl-p-(iodine-123) iodoamphetamine single-photon emission computed tomography (SPECT), disclosed markedly decreased vascular reserves in both patients. After carotid endarterectomy was performed, the hemichorea gradually subsided and SPECT confirmed increased cerebral perfusion. The results in these cases indicate that surgical revascularization is effective for hemichorea due to cerebral ischemia with reduced vascular reserve.