Congestive heart failure caused by silent ischemia and silent myocardial infarction

Ischemic cardiomyopathy: epidemiology, pathophysiology, outcomes, and therapeutic options

Ischemic cardiomyopathy (ICM) is the most prevalent cause of heart failure (HF) in developed countries, with significant morbidity and mortality, despite constant improvements in the management of coronary artery disease. Current literature on this topic remains fragmented. Therefore, this review aimed to summarize the most recent data on ICM, focusing on its definition, epidemiology, outcomes, and therapeutic options. The most widely accepted definition is represented by a left ventricular dysfunction in the presence of significant coronary artery disease. The prevalence of ICM is largely influenced by age and sex, with older individuals and males being more affected. Its pathophysiology is characterized by plaque buildup, thrombus formation, hypoperfusion, ischemic cell death, and left ventricular remodeling. Despite improvements in therapy, ICM still represents a public health burden, with a 1-year mortality rate of 16% and a 5-year mortality rate of approximately 40% in the USA and Europe. Therefore, optimization of cardiovascular function, prevention of progressive remodeling, reduction of HF symptoms, and improved survival are the main goals of treatment. Therapeutic options for ICM include lifestyle changes, optimal medical therapy, revascularization, device therapy, mechanical circulatory support, and cardiac transplantation. Personalized management strategies and tailored patient care are needed to improve the outcomes of patients with ICM.

The potential role of SARS‐CoV‐2 infection in acute coronary syndrome and type 2 myocardial infarction (T2MI): Intertwining spread

Coronavirus disease 2019 (COVID‐19) is a novel pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). It has been shown that SARS‐CoV‐2 infection‐induced inflammatory and oxidative stress and associated endothelial dysfunction may lead to the development of acute coronary syndrome (ACS). Therefore, this review aimed to ascertain the link between severe SARS‐CoV‐2 infection and ACS. ACS is a spectrum of acute myocardial ischemia due to a sudden decrease in coronary blood flow, ranging from unstable angina to myocardial infarction (MI). Primary or type 1 MI (T1MI) is mainly caused by coronary plaque rupture and/or erosion with subsequent occlusive thrombosis. Secondary or type 2 MI (T2MI) is due to cardiac and systemic disorders without acute coronary atherothrombotic disruption. Acute SARS‐CoV‐2 infection is linked with the development of nonobstructive coronary disorders such as coronary vasospasm, dilated cardiomyopathy, myocardial fibrosis, and myocarditis. Furthermore, SARS‐CoV‐2 infection is associated with systemic inflammation that might affect coronary atherosclerotic plaque stability through augmentation of cardiac preload and afterload. Nevertheless, major coronary vessels with atherosclerotic plaques develop minor inflammation during COVID‐19 since coronary arteries are not initially and primarily targeted by SARS‐CoV‐2 due to low expression of angiotensin‐converting enzyme 2 in coronary vessels. In conclusion, SARS‐CoV‐2 infection through hypercytokinemia, direct cardiomyocyte injury, and dysregulation of the renin‐angiotensin system may aggravate underlying ACS or cause new‐onset T2MI. As well, arrhythmias induced by anti‐COVID‐19 medications could worsen underlying ACS.

Identification of Silent Myocardial Ischemia in Patients with Long-Term Type 1 and Type 2 Diabetes

(1) Background: This study aimed to analyze epidemiological data to identify risk factors for silent myocardial ischemia in patients with long-term type 1 and type 2 diabetes. (2) Methods: An analysis was performed on 104 patients with long-term type 1 and type 2 diabetes who had not previously been diagnosed with cardiovascular disease. During hospitalization, patients were subjected to a standard ECG exercise test on a treadmill. If the test could not be performed or the result was uncertain, a pharmacological exercise test with dobutamine was performed. In the case of a positive exercise ECG test or a positive dobutamine test, the patient underwent coronary angiography. (3) Results: Atherosclerotic lesions were found in 24 patients. Patients with silent ischemia were significantly older and had a lower mean left ventricular ejection fraction and a higher incidence of carotid atherosclerosis. The presence of microvascular complications did not increase the risk of silent ischemia. (4) Conclusions: Silent heart ischemia is more common in type 2 than type 1 diabetes. Predisposing factors include older age, coexistence of carotid atherosclerosis, lower left ventricular ejection fraction, and smoking in patients with type 1 diabetes. Concomitant microvascular complications are not a risk factor.

The Impact of Diabetes on Vascular Disease: Progress from the Perspective of Epidemics and Treatments

At present, the global incidence of diabetes has increased in countries with large populations, and the changes in developing regions are particularly worthy of attention. In the past 40 years or so, the income situation in China, India, and other countries has exploded, leading to changes in the way of life and work as well as an increase in the prevalence of diabetes. Metabolic disorders caused by diabetes can lead to secondary vascular complications, which have long-term malignant effects on the heart, kidneys, brain, and other vital organs of patients. Adequate primary prevention measures are needed to reduce the incidence of diabetic vascular complications, and more attention should be given to treatment after the disease. To this end, it is necessary to determine a standardized drug and physical therapy system and to build a more efficient and low-cost chronic disease management system.

Cardiologic Long-Term Follow-Up of Patients Treated With Chest Radiotherapy: When and How?

Introduction: Radiotherapy may cause valvular (VHD), pericardial, coronary artery disease (CAD), left ventricular dysfunction (LVD), arrhythmias. The risk of radiation induced heart disease (RIHD) increases over time. The current guidelines suggest a screening for RIHD every 5 years in the long-term survivors who had been treated by chest RT.

Methods: We reviewed the clinical and instrumental data of 106 patients diagnosed with RIHD. In one group (Group A: 69 patients) RIHD was diagnosed in an asymptomatic phase through a screening with ECG, echocardiogram and stress test. A second group (37 patients) was seen when RIHD was symptomatic. We compared the characteristics of the two groups at the time of RT, of RIHD detection and at last follow-up.

Results: Overall, 64 patients (60%) had CAD (associated to other RIHD in 18); 39 (36.7%) had LVD (isolated in 20); 24 (22.6%) had VHD (isolated in 10 cases). The interval between the last negative test and the diagnosis of moderate or severe RIHD was <5 years in 26 patients, and <4 years in 18. In group A, 63% of the patients with CAD had silent ischemia. The two groups did not differ with regard to type of tumor, cardiovascular risk factors, use of anthracycline-based chemotherapy, age at RT treatment, radiation dose and interval between RT and toxicity detection. The mean time from RT and RIHD was 16 years in group A and 15 in group B. Interventional therapy at RIHD diagnosis was more frequent in group B (54 vs. 30%, p < 0.05). At last follow-up, 27 patients had died (12 of cancer, 9 of cardiac causes, 6 of other causes); mean ejection fraction was 60% in group A and 50% in group B (p < 0.01). Patients with ejection fraction ≤ 50% were 14.5% in group A and 40% in group B (p < 0.01).

Conclusions: Clinically relevant RIHD become evident at a mean interval of 16 years after RT. The most frequent clinical manifestations are CAD and LVD. RIHD diagnosis in asymptomatic patients may preserve their cardiac function with timely interventions. We suggest -after 10 years from radiotherapy- a screening every 2–3 years.

Mechanism of Ferroptosis and Its Role in Type 2 Diabetes Mellitus

Ferroptosis is a novel form of nonapoptotic regulated cell death (RCD). It features iron-dependent lipid peroxide accumulation accompanied by inadequate redox enzymes, especially glutathione peroxidase 4 (GPX4). RAS-selective lethal 3 (RSL3), erastin, and ferroptosis inducing 56 (FIN56) induce ferroptosis via different manners targeting GPX4 function. Acyl-CoA synthetase long-chain family 4 (ACSL4), lysophosphatidylcholine acyltransferase 3 (LPCAT3), and lipoxygenases (LOXs) participate in the production of lipid peroxides. Heat shock protein family B member 1 (HSPB1) and nuclear receptor coactivator 4 (NCOA4) regulate iron homeostasis preventing ferroptosis caused by the high concentration of intracellular iron. Ferroptosis is ubiquitous in our body as it exists in both physiologic and pathogenic processes. It is involved in glucose-stimulated insulin secretion (GSIS) impairment and arsenic-induced pancreatic damage in the pathogenesis of diabetes. Moreover, iron and the iron-sulfur (Fe-S) cluster influence each other, causing mitochondrial iron accumulation, more reactive oxygen species (ROS) production, endoplasmic reticulum (ER) stress, failure in biosynthesis of insulin, and ferroptosis in β-cells. In addition, ferroptosis also engages in the pathogenesis of diabetic complications such as myocardial ischemia and diabetic cardiomyopathy (DCM). In this review, we summarize the mechanism of ferroptosis and especially its association with type 2 diabetes mellitus (T2DM).

The impact of diabetes on heart failure development: The cardio-renal-metabolic connection

Heart failure (HF) and chronic kidney disease (CKD) are often associated in type 2 diabetes (T2D), aggravate each other and exert synergistic effects to increase the risk of cardiac and renal events. The risks of renal worsening in HF patients and HF in CKD patients need to be evaluated to tailor preventive therapy. The recent CV and renal trials enriched our knowledge about the natural history of HF and CKD in T2D and provided evidence for the benefit of sodium-glucose cotransporter 2 inhibitors (SGLT2is) in HF and renal decline prevention. SGLT-2is are the best choice in patients with HFrEF to improve CV prognosis and HF-related outcomes and also to prevent kidney-related outcomes, and in CKD patients to slow down renal failure and also reduce hospitalization for HF and CV death. In both situations the number of patients to treat in order to prevent such events in one patient is lower than in the general T2D population at high CV risk. GLP1-receptor agonists could be an alternative in a patient who is intolerant or has a contraindication to SGLT-2is. A tight collaboration between diabetologists, nephrologists and cardiologists should be encouraged for a holistic and effective strategy to reduce the burden of cardio-renal-metabolic interaction.

Sudden Death from Ischemic Heart Disease While Driving: Cardiac Pathology, Clinical Characteristics, and Countermeasures

BACKGROUND Sudden death from ischemic heart disease while driving is an important cause of traffic accidents. This study discusses causes of traffic accidents in relation to risk factors for acute myocardial infarction such as hypertension and overwork and provides references for the early prevention and regulation of drivers' health conditions. MATERIAL AND METHODS Data on 21 cases of sudden death by ischemic heart disease while driving from January 2015 to December 2019 were collected. Age, symptoms, and cardiac pathological changes of patients were summarized by systematic anatomical and medical history data. RESULTS Patients were 21 men with an average age of 47±7.27 years (most aged 40 to 60 years), and the average weight of their hearts was 439.45±76.3 g. Twelve patients had a history of hypertension, 8 had previous myocardial infarction, and 4 had fatty liver. All had at least 1 severe narrowing of a major coronary artery. Twelve patients died within a short period; 9 died more than 12 h after myocardial infarction onset. Ten patients had worked more than 80 h of overtime per month, 4 patients, more than 45 h, and 7 patients, less than 45 h. CONCLUSIONS Regular physical examination and information about ischemic heart disease should be emphasized for men aged 40 to 60 years who drive frequently, especially for those with hypertension, overwork, or previous myocardial infarction. Incorporating objective evaluation criteria for the severity of ischemic heart disease and overwork into health condition-related driving regulations is needed.

Silent coronary artery disease in type 2 diabetes: a narrative review on epidemiology, risk factors, and clinical studies

Silent coronary artery disease (CAD) is one of the manifestations of heart disease that particularly affects subjects with type 2 diabetes mellitus (T2DM). From a clinical point of view, silent CAD represents a constant challenge for the diabetologist, who has to decide whether a patient could or could not be screened for this disease. In the present narrative review, several aspects of silent CAD are considered: the epidemiology of the disease, the associated risk factors, and main studies conducted, in the last 20 years, especially aimed to demonstrate the usefulness of the screening of silent CAD, to improve cardiovascular outcomes in type 2 diabetes.

Diabetes and the Risk of Sudden Cardiac Death

PURPOSE OF REVIEW

Persons with diabetes mellitus (DM) have increased morbidity and mortality rates compared with persons without DM. Sudden cardiac death (SCD) is a leading cause of death, and multiple studies have found an increased risk of SCD among individuals with DM. This review sought to collect the latest knowledge of the epidemiological and pathophysiological interplay between DM and SCD.

RECENT FINDINGS

Persons with DM have a two- to tenfold increased risk of SCD compared with persons without DM. The underlying mechanisms for the increased risk of SCD are complex and multifactorial. The main pathophysiological contributors are DM-induced cardiac autonomic neuropathy (CAN), metabolic changes, silent ischemia, and polypharmacy. Persons with DM have an increased risk of SCD. Future studies should focus on CAN and the combined risk of QT prolongation from the interplay between CAN, hypoglycemia, and polypharmacy. Genes and pathways involved in control of the autonomic nervous system and cardiac ion channels could be a future focal point.

Issues for the management of people with diabetes and COVID-19 in ICU

In the pandemic “Corona Virus Disease 2019” (COVID-19) people with diabetes have a high risk to require ICU admission. The management of diabetes in Intensive Care Unit is always challenging, however, when diabetes is present in COVID-19 the situation seems even more complicated. An optimal glycemic control, avoiding acute hyperglycemia, hypoglycemia and glycemic variability may significantly improve the outcome. In this case, intravenous insulin infusion with continuous glucose monitoring should be the choice. No evidence suggests stopping angiotensin-converting-enzyme inhibitors, angiotensin-renin-blockers or statins, even it has been suggested that they may increase the expression of Angiotensin-Converting-Enzyme-2 (ACE2) receptor, which is used by “Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to penetrate into the cells. A real issue is the usefulness of several biomarkers, which have been suggested to be measured during the COVID-19. N-Terminal-pro-Brain Natriuretic-Peptide, D-dimer and hs-Troponin are often increased in diabetes. Their meaning in the case of diabetes and COVID-19 should be therefore very carefully evaluated. Even though we understand that in such a critical situation some of these requests are not so easy to implement, we believe that the best possible action to prevent a worse outcome is essential in any medical act.

Prognosis of unrecognised myocardial infarction determined by electrocardiography or cardiac magnetic resonance imaging: systematic review and meta-analysis

OBJECTIVE

To evaluate the prognosis of unrecognised myocardial infarction determined by electrocardiography (UMI-ECG) or cardiac magnetic resonance imaging (UMI-CMR).

DESIGN

Systematic review and meta-analysis of prospective studies.

DATA SOURCES

Electronic databases, including PubMed, Embase, and Google Scholar.

STUDY SELECTION

Prospective cohort studies were included if they reported adjusted relative risks, odds ratios, or hazard ratios and 95% confidence intervals for all cause mortality or cardiovascular outcomes in participants with unrecognised myocardial infarction compared with those without myocardial infarction.

DATA EXTRACTION AND SYNTHESIS

The primary outcomes were composite major adverse cardiac events, all cause mortality, and cardiovascular mortality associated with UMI-ECG and UMI-CMR. The secondary outcomes were the risks of recurrent coronary heart disease or myocardial infarction, stroke, heart failure, and atrial fibrillation. Pooled hazard ratios and 95% confidence intervals were reported. The heterogeneity of outcomes was compared in clinically recognised and unrecognised myocardial infarction.

RESULTS

The meta-analysis included 30 studies with 253 425 participants and 1 621 920 person years of follow-up. UMI-ECG was associated with increased risks of all cause mortality (hazard ratio 1.50, 95% confidence interval 1.30 to 1.73), cardiovascular mortality (2.33, 1.66 to 3.27), and major adverse cardiac events (1.61, 1.38 to 1.89) compared with the absence of myocardial infarction. UMI-CMR was also associated with increased risks of all cause mortality (3.21, 1.43 to 7.23), cardiovascular mortality (10.79, 4.09 to 28.42), and major adverse cardiac events (3.23, 2.10 to 4.95). No major heterogeneity was observed for any primary outcomes between recognised myocardial infarction and UMI-ECG or UMI-CMR. The absolute risk differences were 7.50 (95% confidence interval 4.50 to 10.95) per 1000 person years for all cause mortality, 11.04 (5.48 to 18.84) for cardiovascular mortality, and 27.45 (17.1 to 40.05) for major adverse cardiac events in participants with UMI-ECG compared with those without myocardial infarction. The corresponding data for UMI-CMR were 32.49 (6.32 to 91.58), 37.2 (11.7 to 104.20), and 51.96 (25.63 to 92.04), respectively.

CONCLUSIONS

UMI-ECG or UMI-CMR is associated with an adverse long term prognosis similar to that of recognised myocardial infarction. Screening for unrecognised myocardial infarction could be useful for risk stratification among patients with a high risk of cardiovascular disease.

CVOTs: What did the endocrinologist learn?

The recent CVOTs which tested the new glucose-lowering drugs (GLD) show that in patients with type 2 diabetes mellitus (T2DM) it is now possible to reduce cardiovascular complications including ischemic events and hospitalization for heart failure, and mortality, and, to some extent, microvascular complications of diabetes, in particular renal outcomes. Additionally CVOTs provide major informations on safety and metabolic effects for long-term use of these drugs. The benefits with GLP-1 RAs are most likely derived through the reduction of atherosclerosis-related events while SGLT-2is seem mostly to reduce heart failure-related events. Specific mechanisms independent from glucose control are involved. Based on CVOTs results it is time, as stated in the new EASD-ADA and ESC/EASD guidelines, to take into consideration such opportunities in the decision-making process when treating T2DM patients, favoring the use of drugs that have shown clear cardiovascular and renal benefits. The treatment decisions require more expertise in the evaluation of cardiovascular and renal risk which becomes a major determinant for the choice of GLD treatment, the target for lipids, the adjustment of anti-hypertensive treatments and the prescription of aspirin. In this context it is essential that endocrinologists-diabetologists communicate more with cardiologists and nephrologists and with the primary care practitioners.