Ischemia In Asymptomatic Patients Research Articles

Rates of Ischemia Amongst Asymptomatic Patients with High Coronary Artery Calcium Scores

CACS may be used to recommend lifestyle changes or other treatment recommendations to reduce the risk of heart disease. The incidence of asymptomatic ischemia in patients with elevated CACS is poorly defined. Furthermore, the CACS cut-off above which it is clinically important and cost effective to look for and diagnose ischemia is also not well defined. The purpose of this study is to better define the incidence of asymptomatic ischemia in Parkview Heart Institute (PHI) patients with elevated CACS, including an examination of demographic data that may also influence the rate of ischemia. 118 Patients who were screened for CAD, received CACS ≥ 400, and subsequently had stress testing or invasive coronary angiogram within 6 months were admitted into the study. Through statistical analysis it was determined there was no statistical difference in rates of ischemia between patients with CACS of 400-999 and those >1000. However, due to a small sample size this study will be continued to strengthen its results and investigate if demographics play a role in rates of ischemia.

Coronary Disease Risk in Asymptomatic Patients with Left Ventricular Moderate Dilatation

Goal of the Study is to assess the risk of coronary disease of asymptomatic ischemia in patients with left ventricular moderate dilatation. Methods: The work was based on the results of investigation of 185patients with left ventricular moderate dilatation, aged 35-55 years from the “Tbilisi Heart and Vascular Clinic” contingent. Among them, there are 159 men and 26 women. Results: Patients who suffer from left ventricular moderate dilatation and don’t expose typical symptom of ischemia possibly are in risk of carrying damaged coronary artery. the LV moderate dilatation of the left ventricle can be used for primary diagnosing of silent ischemia. Sensitivity - 0.867(95%CI:0.806-0.927); Specificity – 0.800(95%CI:0.703-0.897); Prognostic value of positive results; 0.889(95%CI:0.832-0.946); Prognostic value of negative results - 0.765(95%CI:0.664-0.866); diagnostic value - 0.843(95%CI:0.791-0.896). Conclusions: In patients with silent ischemia, the coronary disease predictors are: left ventricular moderate dilatation, male gender, dyslipidemia, arterial hypertension, smoking, positive treadmill test, ischemic disease in 1st degree relatives, low tolerance to treadmill test. Thus, we can use the moderate dilatation of the left ventricle for the primary diagnosing of silent ischemia. The test is simple and non-invasive. It is characterized by high sensitivity and specificity and can be used for early diagnosing of silent ischemia and the prevention of cardiac cases.

Vólvulo de intestino medio: a propósito de dos casos.

Intestinal malrotation is defined as an alteration in the rotation and fixation of the intestine during the fetal stage. It can present with a wide clinical spectrum ranging from acute volvulus to chronic duodenal obstruction. Its clinical presentation is therefore also very varied, from asymptomatic patients in whom the diagnosis can be made as a finding, to extremely serious symptoms such as a midgut volvulus. Midgut volvulus is the most severe manifestation of this malformation spectrum, and its presentation without ischemia in asymptomatic patients is a rare formof presentation. The objective of this work is to present the clinical history of two patients with intestinal malrotation who presented a midgut volvulus in the neonatal period. In both cases, a Ladd procedure was performed, requiring in the first patient a extensive intestinal resection due to intestinal necrosis. Both had a good progress in the postoperative period.

Myocardial Ischemia Induced by 5-Fluorouracil: A Prospective Electrocardiographic and Cardiac Biomarker Study.

Cardiotoxicity induced by 5-fluorouracil (5-FU) is well known but poorly understood. In this study, we undertook ECG recording (Holter) and analyses of the biomarkers troponin and copeptin in patients receiving 5-FU to increase our understanding of the cardiotoxicity. Patients with colorectal or anal cancer that received first-time treatment with 5-FU-based chemotherapy were prospectively included. Holter recording, clinical evaluation, 12-lead electrocardiogram, and assessment of plasma concentrations of troponin I and copeptin were performed before (control) and during 5-FU treatment (intervention). A total of 108 patients were included, 82 with colorectal and 26 with anal cancer. The proportion of patients with myocardial ischemia on Holter recording was significantly higher during the first 5-FU infusion (14.1%) than before (3.7%; p = .001). The ischemic burden per day (p = .001), the number of ST depression episodes per day (p = .003), and the total duration of ischemic episodes per day (p = .003) were higher during the first 5-FU infusion than before, as was plasma copeptin (p < .001), whereas plasma troponin I was similar (p > 0.999). Six patients (5.6%) developed acute coronary syndromes and two (1.8%) developed symptomatic arrhythmias during 5-FU treatment. 5-FU infusion is associated with an increase in the number of patients with myocardial ischemia on Holter recording. According to biomarker analyses, 5-FU is associated with an increase in copeptin, but rarely with increases in cardiac troponin I. However, 5%-6% of the patients developed acute coronary syndromes during treatment with 5-FU. Symptomatic 5-fluorouracil (5-FU) cardiotoxicity occurs in 0.6%-19% of patients treated with this drug, but a small electrocardiographic (Holter) study has revealed silent myocardial ischemia in asymptomatic patients, suggesting a more prevalent subclinical cardiac influence. This study demonstrated a significant increase in the number of patients with myocardial ischemia on Holter recording during 5-FU treatment and an increase in ischemic burden. Cardiac biomarker analyses suggested that 5-FU infusion results in endogenous stress (increased copeptin) but rarely induces myocyte injury (no change in troponin). These findings suggest a more prevalent cardiac influence from 5-FU and that Holter recording is an important tool in the evaluation of patients with suspected cardiotoxicity from 5-FU.

Exercise Treadmill Test in Patients with Diabetes Mellitus Type 2

Abstract There is a concern regarding the high incidence of coronary heart disease (CHD) among patients with diabetes mellitus (DM) type 2 since it is a leading cause of mortality in those patients. Exercise treadmill test (ETT) is proposed as a suitable, non-invasive method for identifying asymptomatic patients with ischemic changes, who would benefit from pharmacological treatment, thus contributing to a reduction of adverse cardiovascular events. Therefore the objective of our study was to evaluate myocardial ischemia in asymptomatic patients with DM type 2 by performing ETT. The present investigation was conducted in Health Center Pozega during the year 2018. 40 insulin-dependent, aged 33.05 ± 2.01 years, with DM type 2 were included in the study. They had nor history nor symptoms of cardiac disease. All patients underwent ETT according to Bruce protocol, while 12-lead ECG was recorded and blood pressure was monitored. All patients had negative ETT results. Also no ST segment depression, no signs of insufficiency of peripheral circulation, no changes in heart rhythm, no symptoms by the central nervous system were observed. Additionally response of heart rate and blood pressure to exercise was within physiological range. These promising findings indicate that diabetes didn’t alter myocardial integrity and function, thus suggesting that coronary reserve in examined patients was preserved.

The result of treadmill test in asymptomatic type 2 diabetes mellitus

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;To study the prevalence of silent myocardial ischaemia in asymptomatic patients with type 2 DM&lt;/span&gt;.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;The present study was conducted in the Govt. Medical College and Hospital Aurangabad. During December 2012 to November 2014 with 50 patients. It was two year cross sectional study with the patients of asymptomatic type 2 diabetes mellitus without clinical and electrocardiographic evidence of coronary artery disease. &lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;12 (24%) out of 50 subjects had positive TMT. It correlated with years of duration of diabetes (9 positive TMT cases with duration of diabetes more than 10 years). 5 (25%) out of 20 had serum cholesterol levels &amp;gt;240, Number of positive TMT were higher in patients with LDL &amp;gt;160 [5 (25%) out of 20]&lt;/span&gt;.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;Diabetic patients are at very high risk for cardiovascular morbidity and mortality. Early detection of IHD is very important so that pharmacological therapy, which may improve outcome, can be established. Tread mill exercise TMT being a non-invasive test with high safety, has an important role in early detection of IHD. It is recommended that TMT should be a part of routine management in asymptomatic patients with type II DM. &lt;/span&gt;&lt;/p&gt;

Can myocardial performance index predict the presence of silent ischemia in asymptomatic type 2 diabetic patients?

Coronary artery disease (CAD) is an important cause of morbidity and mortality in patients with diabetes. Silent myocardial ischemia (SMI) is common in patients with diabetes and is associated with poorer prognosis. Myocardial performance index "Tei index" that reflects both left ventricular (LV) systolic and diastolic function. The aim of our study was to test the value of Tei index in prediction of SMI in asymptomatic patients with type 2 diabetes. Asymptomatic patients with type 2 diabetes were included in our study. We excluded patients with known CAD, previous revascularization, low ejection fraction, or abnormal ECG from the study. All patients had undergone history taking and clinical examination, ECG, echocardiography with measuring of Tei index and Holter monitoring for detecting silent ischemia. A total of 200 patients were recruited. We divided our patients into two groups: Group I: 64 patients with SMI, Group II: 136 patients without SMI. There was no significant difference between the two groups regarding clinical and conventional echocardiographic data. Tei index was significantly higher in patients with silent ischemia (P<.00001). Sensitivity, specificity, positive, and negative predictive values of Tei index ≥0.6 in prediction of Holter detected silent ischemia were 85.9%, 90%, 78.6%, and 88.6%, respectively. We found a significant positive correlation between Tei index and number of ischemic episodes (r=.366, P=.0029). Measuring Tei index is helpful in predicting the presence of silent ischemia in asymptomatic patients with type 2 diabetes.

Silent cerebral events/lesions related to atrial fibrillation ablation: a clinical review.

Brain magnetic resonance imaging (MRI) has identified a high incidence of cerebral ischemia in asymptomatic patients after atrial fibrillation (AF) ablation (silent). Detection of cerebral ischemic events on MRI is based on acute hyperintense lesions on diffusion-weighted imaging. In the literature, the incidence is related to specifications of MRI and depends on the definition applied. In comparative studies, silent cerebral events (SCE, diffusion-weighted MRI [DWI] positive only) appear to be approximately 3 times more common compared to using a definition of silent cerebral lesions (SCL; without fluid attenuated inverse recovery sequence [FLAIR] positivity). Whereas the FLAIR sequence may turn positive within days after the ischemic event, SCE definition is highly sensitive for early phases of ischemic brain damage. SCE/SCL appear to represent cerebral ischemic infarcts and determine the "embolic fingerprint" of a specific ablation technology and strategy used. The optimum time point for detecting SCE is early after AF ablation (24-72 hours), whereas detection of SCL can only be performed within the first 2-7 days (due to delay of FLAIR positivity). Different technology-, procedure-, and patient-related parameters have been identified to play a role in the multifactorial genesis of SCE/SCL. In recent years, evidence has been gathered that there may be differences of SCE/SCL rates depending upon the ablation technology used, but small patient numbers and a large number of potential confounders hamper all studies. As major findings of recent studies, mode of periprocedural and intraprocedural anticoagulation has been identified as a major predictor for incidences of SCE/SCL. Whereas procedural characteristics related to higher SCE/SCL-rates may be modified, unchangeable patient-related factors should be taken into account for future individualized risk assessment. Novel ablation devices introduced into the market should be tested for their potential embolic fingerprint and refinements of ablation procedures to reduce their embolic potential should be prompted. The knowledge of "best practice" in terms of low SCE/SCL rates has prompted changes in work-flow, which have been implemented into ablation procedures using novel ablation devices. So far, no study has linked SCE/SCL to neuropsychological decline and the low number of AF-ablation-associated events needs to be weighted against the multitude of preexisting asymptomatic MRI-detected brain lesions related to the course of AF itself. Future studies are needed to evaluate if more white matter hyperintensities due to AF may be prevented by AF ablation (producing only a small number of SCE/SCL).

Place de la scintigraphie myocardique dans le bilan des pathologies cardiaques au centre hospitalier universitaire Yalgado Ouédraogo (CHU-YO) : à propos de 73 cas colligés d’avril 2012 à décembre 2013

The applications of nuclear medicine in cardiology started in April 2012 at the CHU-YO by myocardial scintigraphy. They concern the stress tests coupled with the study of perfusion and myocardial function. After a few months of operation, we propose to determine the contribution of myocardial scintigraphy in the assessment of heart disease at the University Hospital Yalgado Ouedraogo. It came from a retrospective descriptive study under which ran from April 2012 to December 2013, 73 patients were included in the study, all with heart disease and who underwent myocardial scintigraphy. Men were the most represented (60.27%) and the average age was 49years. The majority of patients (73.97%) had at least one cardiovascular risk factors. Search coronary insufficiency was the indication of the most important myocardial scintigraphy representing 58.90% of cases. Of 73 patients, 60 patients or 82.19% of cases received a physical stress test according to the modified Bruce protocol followed by myocardial scintigraphy and examined at rest. Among these patients, in 9 is 15% of cases, ischemia was diagnosed. The integration of myocardial scintigraphy in the assessment of heart disease could contribute to a better management of patients and early diagnosis of ischemia in asymptomatic patients.

Ischaemia-Driven Optimal Therapeutic Approach in Asymptomatic Patients with High Cardiovascular Risk: The Value of Clinical, Laboratory and Myocardial Spect Imaging Findings

We wanted to evaluate the presense of myocardial ischaemia in asymptomatic patients with high cardiovascular risk, the influencing clinical and laboratory factors and the impact of ischaemia on final management decision. We evaluated 60 asymptomatic patients with high CV risk, who underwent SPECT myocardial perfusion imaging (MPI) for detection of suspected CAD. We used the 17 segment model for quantitative and semiquantitative scan perfusion and function analysis using perfusion scores. All patients had full blood laboratory analyses including lipid values, presence of albuminuria, rest and stress ECG. Logistic regression analysis was used to assess the impact of clinical and laboratory parameters on myocardial ischaemia prevalence. Stress-inducible ischaemia was found in 19 pts (33%), fixed defects were found in 13% and mixed defects in 9% of cases. The average ischaemia amount was 10%. Mild ischaemia was found in 12 patients (64%)--summed stress score (SDS)<4, moderate ischaemia in 5 patients (26%)--SDS 5-7 and severely abnormal scans in 2 patients (10%)--SDS>7. Severe ischaemia was only related to the duration of diabetes. Six pts with severe ischaemia had ST depression>2 mm on stress study, and a higher wall motion index and LVEF fall>5% during stress study (p<0.01). Stepwise logistic regression analysis for prediction of stress-induced ischaemia showed OR 2.4 (95% CI 1.7-3.6) for stress-induced ECG changes and OR 3.9 for presence of DM over 10 y (95% CI 2.3-6.6). Seven patients with ischaemia>10%, were referred for coronary angiography. MPI is a valuable method for preclinical assessment of myocardial ischaemia in patients with high CV risk, which can improve prognosis and guide treatment decision.

Predictors of physical inactivity in men and women with type 2 diabetes from the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study.

The purpose of this secondary analysis was to determine changes in physical inactivity from baseline to 5 years and to identify factors associated with and predictive of physical inactivity among individuals with type 2 diabetes enrolled in the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study. DIAD was a prospective randomized screening trial that assessed the prevalence of silent ischemia in asymptomatic patients with type 2 diabetes. Subjects were recruited from diabetes and primary care practices at 14 centers throughout the United States and Canada. This is a secondary data analysis of the physical activity data (type and hours/week) collected. No intervention was conducted. In all subjects, physical inactivity rose from 24% at baseline to 33% at 5 years (S = 28.93; P < .0001). This change was significant in both men (S = 11.44; P < .0001), increasing from 23% to 31%, and women (S = 18.05; P < .0001), increasing from 25% to 36%. Gender differences were noted in several factors associated with baseline physical inactivity as well as in factors predictive of physical inactivity at 5 years. Important factors associated at both time points included lower level of education, current employment, presence of peripheral and autonomic neuropathy, and indicators of overweight/obesity. Baseline physical inactivity was strongly predictive of physical inactivity at 5 years (odds ratio, 3.27; 95% confidence interval, 2.36-4.54; P < .0001). Gender-related differences were noted in factors associated with and predictive of physical inactivity.

Subclinical detection of atherosclerosis and myocardial ishemia in asymptomatic patients with intermediate and high cardiovascular risk: therapeutic and prognostic implications

Background: We wanted to evaluate the presence of coronary atherosclerosis and myocardial ischemia in asymptomatic patients with intermediate and high cardiovascular (CV) risk, the influencing clinical factors and the impact of ischemia on the final management decision and prognosis. Patients and Methods: 75 asymptomatic patients (35 with intermediate and 40 patients with high CV risk-SCORE risk system), underwent single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for the detection of suspected coronary artery disease. We used a 17-segment model for the scan perfusion and function analysis using perfusion scores. All of the patients have full blood laboratory analyses including lipid values, and presence of urine albuminuria. Multislice computer tomography with coronary calcium Agatston score (CAC) for coronary atherosclerosis detection was also performed. The patients were followed up for 12-18 months for cardiovascular events (new chest pain, hospitalization for acute coronary syndrome, revascularization, cardiac death). Logistic regression analysis was used to assess predictive parameters for myocardial ischemia and cardiovascular events. Results: Stress-inducible ischemia was found in 19 patients (33%), fixed defects were found in 13% and mixed defects in 9% of cases. The average ischemia amount was 10%. Mild ischemia was found in 12 patients (64%) summed stress score (SDS) 7. Severe ischemia was only related to the duration of diabetes (DM). Patients with at least moderate ischemia had Agatston CAC score 465+/-112. The patients with normal MPI scan had CAC score 98+/-45. 3 pts with moderate risk were reclassified to high risk by using CAC and MPI scan results. Stepwise logistic regression analysis for the prediction of stress-induced ischemia showed OR 2.4 (95% CI 1.7_3.6) for the stress-induced ECG changes, OR 2.8 for CAC >400 (95% CI 1.9-3.2) and OR 3.9 for the presence of DM over 10y (95% CI 2.3_6.6). Seven patients with ischemia >10%, were referred for coronary angiography. One patient was hospitalized due to the acute coronary syndrome and no cardiac death was registered during the 12 months follow-up. Conclusions: MPI is a valuable method for preclinical assessment of myocardial ischemia in asymptomatic intermediate and high risk patients, which can improve the prognosis and guide the treatment decision. Coronary calcium score can predict the presence of myocardial ischemia and reclassify the patient's risk.

Atypical Manifestation of Myocardial Ischemia in the Elderly

Often, elderly patients have atypical clinical picture for myocardial ischemia, or are asymptomatic. This review intends to re-examine the pathophysiology of atypical manifestation in elderly persons, its prognostic and therapeutic implications. The coronary atherosclerotic disease is an increasing public health problem, of particular importance in higher age groups. Its prevalence increases significantly at the sixth decade of life, becoming the leading cause of death in older people, as well as the greatest responsible for hospitalization and invasive procedures1. The absent or atypical clinical signs in elderly persons hinder the management of coronary atherosclerotic disease. The cases of myocardial ischemia without pain, the so-called asymptomatic or silent ischemia, it is more frequent in elderly patient2. Considering patients with acute coronary syndrome, as myocardial infarction with ST-segment elevation, among those under 65 years of age, only 11.1% do not have precordial pain, unlike those over 85 years old, among which 43.2% have precordial pain3. Similarly, among elderly patients with Q wave in electrocardiogram (ECG), 78% did not have symptoms of precordial pain4 (Figure 1). Figure 1 Clinical presentation of acute myocardial infarction according to age. Bayer AJ, Chadha JS, Farag RR, Pathy MS. J Am Geriatr Soc. 1986; 34:263-6. Diabetes mellitus has been considered the biggest factor related to asymptomatic ischemia in patients with stable coronary disease. However, several studies found no such association5. These studies indicate that the only independent factor for silent ischemia is advanced age. In fact, progressive increase occurs in the interval between the beginning of ST segment depression and the onset of angina with increased age6, indicating increased pain threshold among elderly. When an episode of coronary blood flow reduction occurs, the first alteration is the suffering of myocyte, following changes of myocardial relaxation and ST segment depression. Pain is the last manifestation of myocardial ischemia7. The higher prevalence of asymptomatic myocardial ischemia or with atypical symptoms in elderly is explained by increased pain threshold related to nociceptive changes and by the great prevalence of diseases such as depression and diabetes mellitus. Increased beta-endorphins levels have also been described in patients with asymptomatic myocardial ischemia8. However, there are studies with different findings9,10. Additionally, patients suffering from silent ischemia have central nervous activation different from those with angina when subjected to ischemic dobutamine stress, predominating the frontal cortex and ventral temporal activation11. Interestingly, the thalamic area, which is responsible for the recognition of pain, had similar activation in patients with and without angina12. On the other hand, the elderly patients have comorbidities that may influence the clinical manifestation of myocardial ischemia. Even the diabetes mellitus is a condition whose prevalence increases with age, as well as diabetic neuropathy. Fibromyalgia and depression are neuropsychiatric conditions that interfere with the painful sensation. Sometimes, elderly persons complain of precordial pain, with rejected diagnosis of myocardial ischemia, improve with antidepressants. The opposite can also occur, with elderly people with atypical pain for myocardial ischemia, generally attributed to depression, having significant coronary disease. The relationship between depression and coronary atherosclerotic disease is well defined13. However, there are several reasons why depression increases the occurrence of coronary disease. Patients with depression have less treatment adherence to drug and lifestyle changes. Additionally, depression14 can cause change of endothelial function, deregulation of the hypothalamic-pituitary-adrenal axis, increased platelet reactivity and inflammatory markers with interleukin 6. Memory changes, which are frequent in elderly patients, as Alzheimer's disease and vascular dementia, are characterized by the loss of short term memory. Consequently, in these patients, the reliable reporting of symptoms of recent onset is affected. Both Alzheimer's disease and vascular dementia have risk factors similar to those of coronary disease. As a result, besides frequent concomitance, memory deficit causes elderly to have memorization difficulty and describe the pain resulting from myocardial ischemia. Among elderly patients with heart failure, 50-70% have myocardial ischemia as etiology, and considerable part of them have prior myocardial revascularization. Both heart failure15 and myocardial revascularization reduce cognitive performance, especially in the field of attention. Thus, if a patient has myocardial ischemia, this cognitive deficit can impair description of the pain characteristics. In conclusion, elderly patients with myocardial ischemia often have atypical clinical manifestations, due to comorbidities as diabetes mellitus, nociceptive changes, depression and dementia. Therefore, in elderly patients, atypical symptoms of coronary insufficiency should be valued, and to confirm or not diagnosis of myocardial ischemia, the search through additional tests should be more rigorous. Additionally, these research tests on myocardial ischemia also identify patients at higher risk that should be treated more intensively.

Association between cardiac valvular calcification and myocardial ischemia in asymptomatic high-risk patients with end-stage renal disease

ObjectiveValvular calcification is associated with significant morbidity and mortality in patients with end stage renal disease (ESRD). This study examined the hypothesis that valvular calcification is a marker of myocardial ischemia in asymptomatic high-risk patients with ESRD. MethodsEchocardiography and myocardial perfusion single-photon emission computed tomography were performed in 285 asymptomatic high-risk patients with ESRD at initiation of dialysis. We evaluated the extent and severity of myocardial ischemia by the summed difference score (SDS) and defined the presence of myocardial ischemia as SDS ≥ 3 and moderate to severe ischemia as SDS ≥ 8. The presence of cardiac valvular calcification was assessed by echocardiography and defined as aortic valve calcification or mitral valve calcification. ResultsEighty-five (29.9%) patients had echocardiographic evidence of cardiac valvular calcification. The presence of myocardial ischemia was significantly associated with aortic valve calcification (odds ratio [OR] = 3.19; 95% confidence interval [CI] = 1.76–5.78; p < 0.001), mitral valve calcification (OR = 3.31; 95% CI = 1.74–6.28; p < 0.001), and cardiac valvular calcification (OR = 3.18; 95% CI = 1.79–5.65; p < 0.001). The presence of moderate to severe myocardial ischemia (SDS ≥ 8) was independently associated with cardiac valvular calcification (OR = 2.86; 95% CI = 1.12–7.27; p = 0.028). ConclusionValvular calcification was significantly associated with the presence of inducible myocardial ischemia in asymptomatic patients with ESRD, and may be a potential marker of patients at high-risk for the presence of silent myocardial ischemia.

Left atrial volume index is a predictor of silent myocardial ischemia in high-risk patients with end-stage renal disease

Silent myocardial ischemia is highly prevalent in patients with end-stage renal disease (ESRD), and is associated with poor cardiovascular outcomes. However, the criteria for coronary artery disease screening remain unclear in asymptomatic patients. The goal of this study was to evaluate whether baseline echocardiographic parameters can predict myocardial ischemia in asymptomatic patients with ESRD. We investigated 259 high-risk asymptomatic patients with ESRD who underwent both echocardiography and myocardial perfusion single-photon emission computed tomography at the initiation of dialysis. We defined the presence of myocardial ischemia as a reversible or fixed perfusion defect. Silent myocardial ischemia was found in 99 (38.2 %) high-risk asymptomatic patients with ESRD at the initiation of dialysis. In patients with myocardial ischemia, left ventricular (LV) end systolic volume index, LV mass index, left atrial volume index (LAVI), and the ratio of early mitral inflow velocity to peak mitral annulus velocity were significantly higher, and LV ejection fraction was significantly lower, than those without myocardial ischemia. Multivariate analysis showed that LAVI, LV ejection fraction, and regional wall motion abnormalities were independently associated with the presence of silent myocardial ischemia. Severe (LA) enlargement was independently associated with the presence of silent myocardial ischemia (odds ratio 1.97; 95 % confidence interval 1.08-3.57; p = 0.026). LA enlargement is a potential marker for identifying patients with ESRD at high risk of silent myocardial ischemia.

Detection of silent myocardial ischemia in asymptomatic patients with diabetes: results of a randomized trial and meta-analysis assessing the effectiveness of systematic screening.

BackgroundMost guidelines recommend a systematic screening of asymptomatic high risk patients with diabetes for silent ischemia, but the clinical benefit of this strategy has not been demonstrated compared with the simple control of cardiovascular risk factors. We sought to determine whether referring asymptomatic diabetic patients for screening of silent ischemia decreases the risk of cardiovascular events compared with usual care.MethodsDYNAMIT was a prospective, randomized, open, blinded end-point multicenter trial run between 2000 and 2005, with a 3.5 year mean follow-up in ambulatory care in 45 French hospitals. The study included 631 male and female with diabetes aged 63.9 ± 5.1 years, with no evidence of coronary artery disease and at least 2 additional cardiovascular risk factors, receiving appropriate medical treatment. The patients were randomized centrally to either screening for silent ischemia using a bicycle exercise test or Dipyridamole Single Photon Emission Computed Tomography (N = 316), or follow-up without screening (N = 315). The main study end point was time to death from all causes, non-fatal myocardial infarction, non-fatal stroke, or heart failure requiring hospitalization or emergency service intervention. The results of a meta-analysis of DYNAMIT and DIAD, a similar study, are also presented.ResultsThe study was discontinued prematurely because of difficulties in recruitment and a lower-than expected event rate. Follow-up was complete for 98.9% patients regarding mortality and for 97.5% regarding the main study end point. Silent ischemia detection procedure was positive or uncertain in 68 (21.5%) patients of the screening group. There was no significant difference between the screening and the usual care group for the main outcome (hazard ratio = 1.00 95%CI 0.59 to 1.71). The meta-analysis of these and DIAD results gave similar results, with narrower confidence intervals for each endpoint.ConclusionsThese results suggest that the systematic detection of silent ischemia in high-risk asymptomatic patients with diabetes is unlikely to provide any major benefit on hard outcomes in patients whose cardiovascular risk is controlled by an optimal medical treatment.Trial registrationClinicalTrials.gov: NCT00627783

Diabetic Foot Ulcer is a Significant Predictor of Silent Myocardial Ischemia in Women with Type 2 Diabetes

Introduction: Screening silent myocardial ischemia in asymptomatic patients with type 2 diabetes is still controversial. The purpose of the present study was to define the value of diabetic foot ulcer (DFU) in the prediction of silent myocardial ischemia in asymptomatic men and women with type 2 diabetes. Methods: We performed a cross sectional study on 150 diabetic patients with DFU, as cases, and 90 diabetic patients, without the history of any type of DFU, as controls. Presence of silent myocardial ischemia was assessed by dipyridamole single-photon emission- computed tomography myocardial perfusion (SPECT) imaging with thallium-201. Results: Patients with DFU had longer diabetes duration, higher serum HbA1C, and lower serum high density lipoprotein cholesterol levels, compared to patients without DFU. There were a greater number of women with silent myocardial ischemia (28/63 (44.4%) vs. 28/87 (32.2%); p<0.05) in patients with DFU compared to men. There were a greater number of men with silent myocardial ischemia compared to women (10/47(21.3%) vs. 2/43 (4.7%); p<0.05) in patients without DFU. Logistic regression analysis demonstrated that the odds ratio of having silent myocardial ischemia was 2.96 in women with DFU, 0.18 in women without DFU and 1.75 in men with DFU compared to men without DFU, adjusting for HbA1c, HDL-C and diabetes duration. Discussion: Women with DFU are at an increased risk of having silent myocardial ischemia, compared to male counterparts.

Acute Silent Cerebral Ischemia Occurs More Frequently Than Silent Cerebral Infarction In Children with Sickle Cell Anemia

AbstractAbstract 268 Background:Children with sickle cell anemia (HbSS) are at high risk of overt stroke and clinically silent cerebral infarction (SCI). SCI is an infarct-like lesion visualized on magnetic resonance imaging (MRI) of the brain that produces no corresponding motor or sensory deficits. The prevalence of SCI in HbSS is approximately 20 – 30% by 16 years of age, but less is known about its incidence. The Cooperative Study of Sickle Cell Disease (CSSCD) found the incidence of new or more extensive SCI in children with HbSS to be 7 events per 100 patient-years. Given that SCI is clinically silent, the only way to determine its incidence (the number of new events occurring in a specific time-period) is to screen with two sequential MRIs of the brain. MRI can also detect acute cerebral ischemia in asymptomatic patients using diffusion-weighted imaging (DWI). The incidence of acute silent cerebral ischemic events (ASCIEs) is not known. A clinical trial setting provides a unique opportunity to determine the incidence of ASCIEs and SCI in children with HbSS. Objectives:To determine the incidence rates of (1) ASCIEs in children with HbSS without prior evidence of focal neurological deficits and (2) new, recurrent SCI in children with HbSS who have pre-existing SCI. Methods:We studied a cohort of children with HbSS and sickle-β0-thalassemia who had brain MRIs for the Silent Infarct Transfusion Trial. All participants had no prior history of overt stroke, seizures, or transient ischemic attacks. ASCIE was defined as an infarct-like lesion on brain MRI without corresponding motor or sensory deficits that appeared as a focus of T2 hyperintensity with restricted diffusion on DWI sequences. SCI was defined an infarct-like lesion without corresponding motor or sensory deficits that appeared as a focus of T2 hyperintensity without restricted diffusion. Given that acute cerebral ischemia appears as a focus of restricted diffusion on DWI for 10 days, we assumed that each MRI scan provided 10 patient-days of observation for detecting ASCIE. Therefore, the incidence of ASCIEs was calculated using a single MRI per patient. The incidence of new or more extensive SCI in children with pre-existing SCI was determined in those who had two MRIs each (screening and pre-randomization). We statistically compared the incidence rates of ASCIEs and SCI obtained by these two different methods. For all ASCIEs and new SCI events, a medical history tool was completed at the local site at the time of MRI of the brain. Results:In total, 972 MRIs were studied (745 screening, 227 pre-randomization). There were 844 MRIs with DWI sequences, providing 23.1 patient-years of observation in 640 children (52% male; mean age 9.7 years). ASCIEs were detected on 1.2% (10 of 844 MRIs), corresponding to an incidence of 43.3 (95% CI: 20.7 – 79.6) events per 100 patient-years. Nine of the 10 ASCIEs were detected incidentally; 1 ASCIE occurred in a participant who was recovering from a recent episode of acute chest syndrome (onset 5 days before MRI) complicated by severe anemia and hypertension. Standard neurological examination was normal in all cases. Two of the 10 participants with ASCIEs had follow-up MRIs of the brain 4 to 10 months later; one had SCI in the same location as the previously detected acute ischemia, but the other had no residual lesion in the same location. Thus, not all ASCIEs produce detectable SCI. A total of 220 participants (55% male; mean age 10.0 years) had both screening and pre-randomization MRIs. The mean interval between the two MRIs was 124.3 days (range: 14 – 645), providing 74.9 patient-years of observation. All screening MRIs showed baseline SCI. New, recurrent SCI was detected on pre-randomization MRI in 8 participants, corresponding to an incidence of 10.7 events per 100 patient-years (95% CI: 4.6 – 21.0). The incidence of ASCIEs was 4-fold higher than recurrent SCI (43.2 vs. 10.7 events per 100 patient-years; P=0.001). Conclusions:The incidence of recurrent SCI was similar to CSSCD findings. However, we show that children with HbSS experience acute cerebral ischemic events far more frequently than previously recognized. These acute ischemic events are mostly clinically silent, potentially reversible radiographically, and not associated with antecedent medical events. Disclosures:No relevant conflicts of interest to declare.

Threshold, incidence, and predictors of prognostically high-risk silent ischemia in asymptomatic patients without prior diagnosis of coronary artery disease

BackgroundLittle is known about incidence, threshold, and predictors of prognostically relevant silent ischemia (SI). The aim was to study these three aspects of silent coronary artery disease (CAD). MethodsIn total, 3,664 consecutive asymptomatic patients without prior diagnosis of CAD undergoing myocardial perfusion SPECT (MPS) were evaluated and followed-up ≥1 year for Events (HE): cardiac death or myocardial infarction. MPS was interpreted using a 20 segment model to define summed stress, rest, and difference scores (the extent of % myocardium ischemic was derived). Prognostic high-risk ischemia was defined as ischemia consistent with a HE rate ≥3%. ResultsOverall, ≥7.5% myocardium ischemic was consistent with high risk. Twenty-one and six percent of patients had ischemia and high-risk ischemia, respectively. Patients with high-risk ischemia had a worse prognosis than patients with less SI, HE rate of 3.1 and 0.4%, respectively, (P = .0001). Sex, age, diabetes, hypertension, abnormal resting ECG, angina, peak heart rate, blood pressure during treadmill testing, ST-depression, and Duke treadmill score were independent predictors of relevant SI. ConclusionsIn total, ≥7.5% myocardium ischemic revealed to be consistent with high risk. Six percent of patients had evidence of high-risk SI. Diagnostic scores are provided to most likely identify patients with high-risk SI.

Screening for Coronary Disease in Diabetes: When and How

IN BRIEF Coronary atherosclerosis and silent ischemia are highly prevalent in patients with diabetes. Identification of subclinical atherosclerosis and ischemia in asymptomatic patients with diabetes is valuable for risk stratification and for guiding therapy. This article reviews methods of screening and proposes how to implement them in practice.