Prevalence of unrecognized or “silent” myocardial ischemia in chronic kidney disease patients: Protocol for a systematic review and meta-analysis

Introduction Chronic kidney disease (CKD) patients are at an extremely high risk of silent myocardial ischemia (SMI). However, there is a dearth of evidence on the worldwide prevalence of this very lethal and yet unrecognizable complication of CKD. The proposed systematic review and meta-analysis aims to estimate the global prevalence of SMI among CKD patients. Methods and analyses This protocol was conceived according to the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) statement. The systematic review will involve all observational studies and clinical trials published until April 30, 2021, and reporting on the prevalence of SMI in CKD patients. Electronic sources including MEDLINE, Embase, Web of Science, and Cochrane database of systematic reviews will be perused for potentially eligible studies, restricted to only studies published in English or French. Two investigators will independently select studies and use a pre-pilot tested form to extract data. Further, they will independently perform a qualitative assessment of the risk of bias and overall quality of the selected studies, followed by a quantitative assessment using funnel plots and Egger’s tests. The heterogeneity between studies will be assessed with the Cochrane’s Q statistic, and the I2 statistic will measure the percentage of variation across studies that is due to their heterogeneity rather than chance; the I2 will decide if a meta-analysis can be conducted. In case it cannot be conducted, a descriptive analysis will be performed. Otherwise, study-specific estimates will be pooled using either a fixed-effects or a random-effects model, depending on the value of the I2 statistic. Subgroup and random effects meta-regression analyses will further investigate the potential sources of heterogeneity. Finally, sensitivity analyses will be performed to measure the impact of low-quality studies on the results of the meta-analysis, and power calculations will determine the probability that we will detect a true effect if it does exist. PROSPERO registration number CRD42020211929 Strengths and limitations of this study The intended systematic review and meta-analysis will fill the knowledge gap on the global prevalence of silent myocardial ischemia (SMI) in CKD patients. The eligible studies will be identified through a methodic literature search followed by a rigorous screening process; we will then use robust meta-analysis tools to pool the data and provide reliable estimates of the global prevalence of SMI in CKD patients. Two major limitations could be: the predominance of clinical trials that might limit the generalizability of the findings, given that some informative patients might have been sidelined by the strict inclusion criteria of these studies; the high probability of type 1 error originating from the important number of subgroup and sensitivity analyses.

Silent myocardial ischemia in patients with type 2 diabetes mellitus: a clinical case

Background. Type 2 diabetes mellitus (DM) is an important medical, social, and economic problem due to the high prevalence of the disease, which often leads to disability and significantly increases mortality in elderly people. One of the causes of coronary heart disease (CHD) in patients with type 2 DM is autonomic cardiovascular neuropathy, which is characterized by damage to the autonomic nervous system and manifests itself in a varying clinical picture, including silent myocardial ischemia (SMI). The prevalence of SMI among patients with type 2 DM is much higher than in people without it. The purpose was to study the cli­nical case of a patient with type 2 DM and CHD, raise awareness of the prevalence and influence of type 2 DM on CHD progression by focusing on diagnostic research and treatment strategies. Materials and methods. The clinical case of the detected silent ischemia in a patient with type 2 DM was analyzed. The complaints were as following: high blood pressure, moderate shortness of breath du­ring walking, pain, and numbness of the lower extremities. Ana­mnesis: type 2 DM over 20 years; endovascular stenting of the right common iliac artery due to obliterating atherosclerosis of the arteries of the lower extremities; hypertension over 10 years; obesity. Based on this data, CHD was suspected. Results. The Holter monitoring revealed rare episodes of reversible ischemic repolarization. ECG demonstrated the deviation of the electrical axis to the left, hypertrophy of the left ventricular myocardium, diffuse violation of repolarization processes. Ultrasound of the heart found aortic atherosclerosis, left ventricular myocardial hypertrophy, a moderate decrease in myocardial contractility. Ultrasound of vessels of the lower extremities showed the signs of oblitera­ting atherosclerosis with decompensation of peripheral blood flow. Coronary angiography demonstrated left coronary artery with critical subocclusions (90 %), right coronary artery with chronic occlusion in the middle segment (100 %). There was established the diagnosis: coronary heart disease (silent ischemia); diffuse stenotic atherosclerosis of the coronary artery (coronary angiography May 2019); arterial hypertension II stage, degree 2; HF II stage; II NYHA; type 2 diabetes mellitus, insulin-dependent, decompensated; obesity I stage; obliterating atherosclerosis of the arteries of the lower extremities (condition after endovascular stenting of the right common iliac artery on January 2018); chronic pancreatitis in remission, peptic ulcer of the duodenum (operated in 1981); chronic cholecystitis in remission. The treatment was prescribed: insulin therapy, nebivolol, eplerenone, candesartan, clopidogrel, rosuvastatin. Coronary artery bypass grafting is recommended. Conclusions. Thereby, timely diagnosis and adequate treatment can avoid complications of type 2 DM and improve quality and lifetime. With type 2 DM, CHD is often masked and remains undiagnosed, leading to complications and death, therefore more attention to such patients is needed.

Assessing the Prevalence and Predicting Factors of an Abnormal Gated Myocardial Perfusion SPECT in Asymptomatic Patients with Type 2 Diabetes

IntroductionConsidering the significant prevalence of silent myocardial ischemia and its related morbidity and mortality in asymptomatic type two diabetic patients, it is not well known whether early screening with MPI is cost-effective. However, predicting factors are not elucidated. Materials and MethodsThis was a cross-sectional study including 63 asymptomatic patients with type 2 diabetes mellitus (T2DM), with normal ECG and ejection fraction. Patients with any history of documented valvular, congestive or ischemic heart disease, renal or hepatic failure were excluded. At first all patients were interviewed and checked for risk factors and then patients underwent a two-day rest/stress 99mTc-MIBI gated MPI SPECT. Data was assessed by QPS/QGS and 4DM software and evaluated by a nuclear medicine specialist with summed stress score (SSS) of more than 4 defined as CAD. ResultsThere were 42 females (67%) and 21 males (33%), with a mean age of 61.33 ± 6.98 years and 7.97 ± 4.86 years history of T2DM. CAD was detected in 26 (41.3%) patients and was significantly associated with male gender, smoking, requiring insulin therapy and EF (P-value = 0.019, 0.046, 0.05, 0.033, respectively). A significant association was found between the duration of diabetes, especially when >15y, and the probability of having CAD.. Multivariable logistic regression revealed that smoking; male gender and diabetes duration were the strongest independent predictors of abnormal MPI results.ConclusionWe found a high (46%) prevalence of abnormal stress MPI SPECT in patients with type 2 diabetes mellitus, despite being asymptomatic. Asymptomatic patients with a history of smoking, long duration of diabetes, being under insulin treatment and male gender might benefit from MPI for early detection of silent ischemia.

Wearable Devices: A Future Useful Tool for Detection of Silent Ischemia in Patients with Diabetes?

As smartphone health care technology continues to evolve, many wearable devices are equipped with Electrocardiographic (ECG) recording. Recently, studies examining the possibility of various wearable devices for continuous ECG recording showed their ability to detect ST-segment alterations. It is known that in almost a quarter of people with diabetes, the presentation of an acute coronary syndrome may be atypical or even asymptomatic (“silent”), and it has been associated with adverse prognosis. The precise mechanisms behind the lack of pain in patients suffering from silent myocardial ischemia remain unknown. The attractive hypothesis that clinicians could use a wearable ECG recording to detect and treat earlier patients suffering from silent myocardial ischemia might change the adverse prognosis of those patients. However, before their clinical application, several obstacles should be overcome in order the physicians to obtain an additional powerful tool in the fight against coronary artery disease in people with diabetes.

Influence of silent myocardial ischemia on the life quality in patients with ischemic heart disease

The aim of the study was to evaluate the effect of silent myocardial ischemia on the life quality and on the frequency of occurrence and severity of depressive disorders in patients with Ischemic Heart Disease. Materials and methods. The study involved 93 persons, including 42 practically healthy individuals and 51 patients with Ischemic Heart Disease: silent myocardial ischemia. The study included males, aged 45 to 60 years old. To assess the life quality, the Russian validated version of the Medical Outcomes Study-Short Form (SF-36) questionnaire developed by the Boston Institute of Health was used. The Hamilton Depression Rating Scale (HDRS) was used to study the psycho-emotional state of the patients. Statistical data analysis was performed using the Statistica 10.0 and Microsoft Excel 2010 software package. Results. Role functioning (RF) was reduced by 32 % (p<0.0001), general health (GH) was reduced by 31 % (p<0.0001), and mental health was reduced (MH) by 32 % (p<0.0001), social functioning (SF) decreased by 30 % (p<0.0001) in patients with silent myocardial ischemia compared to healthy persons. Both integral indicators of life quality were also reduced in the patients with silent myocardial ischemia compared to the control group. The integral indicator «Physical component of health» for group I was 52.24 [37.4; 59.8] and for group II – 48.84 [41.08; 53.01], p<0.001. The integral indicator «Mental health component» for group I was 54.00 [51.45; 56.76] and for group II – 47.09 [30.29; 52.71], p<0.00001. Mild to moderate depression was found in 35.3 % of the patients with silent myocardial ischemia, and 15.68 % was with severe and extremely severe depression.Conclusions. Silent myocardial ischemia decrease the life quality of patients and promotes the development of depressive states.

Prevalence of asymptomatic or “silent” myocardial ischemia in diabetic patients: Protocol for a systematic review and meta-analysis

Introduction Myocardial ischemia (MI) is a top ranked cause of death among diabetic patients, yet it is mostly asymptomatic or “silent”. There is a need for summary epidemiologic measures on this highly lethal and unnoticeable complication of diabetes. The proposed systematic review and meta-analysis aims to estimate of the global prevalence of silent MI among diabetic patients. Methods and analysis This protocol was prepared according to the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) statement. The systematic review will include all observational studies published until March 23, 2021 and reporting on the prevalence of silent MI in diabetic patients. Electronic sources including MEDLINE(PubMed), Embase, Cochrane Library, and Web of Science will be searched for potentially eligible studies, restricted to only studies published in English. Two investigators will select studies and use a pre-pilot tested form to extract data. Further, they will independently perform a qualitative assessment of the risk of bias and overall quality of the selected studies, followed by a quantitative assessment using funnel plots and Egger’s tests. The heterogeneity between studies will be assessed with the Cochrane’s Q statistic, and the I2 statistic will measure the percentage of variation across studies that is due to their heterogeneity rather than chance; it will decide if a meta-analysis can be conducted. In case a meta-analysis cannot be conducted, a descriptive analysis will be performed. Otherwise, study-specific estimates will be pooled using either a fixed-effects or a random-effects model depending on the value of the I2 statistic. Subgroup and random effects meta-regression analyses will be used to further investigate the potential sources of heterogeneity. Finally, sensitivity analyses will be performed to measure the impact of low-quality studies on the results of the meta-analysis, and power calculations will determine the probability that we will detect a true effect if it does exist. Strengths and limitations of this study The intended review will provide an up-to-date summary of the global prevalence of silent MI in diabetic patients. We will conduct a thorough literature search for eligible studies, and we will use robust meta-analysis tools to provide reliable estimates of the global prevalence of silent MI in diabetic patients. Two major limitations could be: the predominance of clinical trials that might limit the generalizability of the findings, given that the strict inclusion criteria of these studies might have excluded other patients; the risk of type 1 error emanating from the high number of subgroup and sensitivity analyses. PROSPERO registration number CRD42019138136.

Diabetes Mellitus with Silent Myocardial Ischemia: A Single-Center Cross-Sectional Study of Karachi, Pakistan

Background: Previous studies have established the fact that diabetic patients are predominantly inclined towards silent myocardial infarction (SMI). The objective of the present study is to determine the incidence of SMI in diabetes mellitus (DM) patients. Methodology: In this cross-sectional study, patient data was gathered on a predesigned proforma regarding the detailed history of dyspnea, DM and its duration, chest pain either present or not. Those patients who had normal ECG labeled negative for SMI, while those who had either ST-segment elevation or ST-segment deviation on resting ECG were positive for SMI. Study was conducted at the National Institute of Cardiovascular Diseases (NICVD) Karachi- Pakistan. Results: The mean age of the enrolled patients was 54.21±8.65 (40-70) years. Out of 210, majority were female (51.90%).Overall, 94(44.76%) patients were obese, 122(58.09%) were hypertensive, 90(42.85%) had dyslipidemia and 98(46.66%) diabetic patients were smokers. There were 93 (44.3%) DM patients who had SMI. Moreover, 109(51.90%) patients had a family history of myocardial ischemia. Conclusion: The SMI incidence among diabetic patients was found higher in local population. It is proposed that diabetic patients with demonstrated cardiovascular autonomic neuropathy must be screened for the manifestation of SMI.