Current Cardiology Reviews - Volume 16, Issue 4, 2020

Background: To report the cardiovascular and renal effects of incretin-based therapies. Methods: The studies of clinical trials on incretin-based therapy published in medical journals from the years 2010 to 2017 were comprehensively searched using MEDLINE and EMBASE with no language restriction. The studies were reviewed and the cardiovascular and renal risks reported were recorded. Results: Incretin-based therapeutics represent novel and promising anti-diabetes drugs, the direct cardiovascular actions which may translate into demonstrable clinical benefits on cardiovascular outcomes. Furthermore, incretin-based therapies do not adversely affect renal function.

A new group of hypoglycemic drugs has been used to treat diabetes type 2. This group is active sodium glucose co-transporter (SGLT2) or SGLT2 inhibitors. It has been shown that besides the treatment of diabetes, this drug class is responsible for the mildness of the cardiovascular events shown in patients with diabetes type 2. However, there is an intriguing question regarding the range of SGLT2 inhibitors and if there is a difference between them or if there is a class effect among their results. EMPA-REG OUTCOME trial and the CVD-study are used to answer this question. Additional information from the DECLARE-TIMI 58 and Dapa-HF trials is studied.

The globalization of the Western lifestyle has resulted in increase of diabetes mellitus, a complex, multifactorial disease. Diabetes mellitus is a condition often related to the disorders of the cardiovascular system. It is well established that three quarters of diabetics, aged over 40, will die from cardiovascular disease and are more likely than non-diabetics to die from their first cardiovascular event. Therefore, it is of paramount importance to individualize treatment via risk stratification. Conditions that increase cardiovascular risk in people with diabetes include age more than 40 years, male gender, history of relative suffering from premature CHD, blood pressure and high LDL levels, presence of microalbuminuria, obstructive sleepapnea, erectile dysfunction and other conditions. Several models have been developed in order to assess cardiovascular risk in people with and without diabetes. Some of them have been proven to be inadequate while others are widely used for years. An emerging way of risk assessment in patients with diabetes mellitus is the use of biomarkers but a lot of research needs to be done in this field in order to have solid conclusions.

Introduction: Cardiovascular, together with renal disease, claims a significant proportion of morbidity and mortality in association with type 2 diabetes mellitus (T2DM) and obesity. To improve the long-term renal and cardiovascular outcome, there is the incorporation of bariatric surgery (BS), which seems to be a pivotal intervention. Areas Explored: Cohort studies and randomized controlled trial (RCT) research of BS among patients with T2DM, were conducted by screening, and then information on renal effects and the cardiovascular outcome was gathered. Metabolic surgery (MS) and BS reduce both mortality and the risk of cardiovascular disorder, chronic kidney diseases and albuminuria. MS refers to a surgical approach, the primary intent of which is the control of metabolic alterations/hyperglycemia in contrast to BS which is a mere weight-reduction therapy. Patients suffering from poor glycaemic control and other macro and micro-vascular diseases will benefit from a surgical approach. The approach implicates hypertension glomerular remission, gut microbiota shift, reduced renal inflammation and fewer instances of chronic cardiac remodelling. Conclusion: MS is beneficial where the main aim is to attain significant and long-lasting weight loss results. The RCTs have depicted the superiority which surgical mechanisms hold over medically- based therapy, for enhancing glycaemic control, and achieving remission of diabetes. This type of surgery improves life quality, reduces incidences of other obesity and diabetes related diseases like microvascular disases, sleep apnea, fatal disorder, and fatty liver disease.

Background: Introduction of new generations of stents has decreased the percentage of patients experiencing in-stent restenosis (ISR) following the implantation of stent. However, a large number of patients are still afflicted with this phenomenon, which necessitates further study of ISR pathophysiology. Methods: Relevant English literature was searched up to 2018 and retrieved form the PubMed database and Google Scholar search engine. The following keywords were used: "In-stent restenosis", "Platelet", "Chemokine", "Inflammation", "Vascular smooth muscle cell" and "Neointima". Results: Previous studies have shown that ISR is a pathophysiologic response to damage of the artery wall after its elongation and separation of the atherosclerotic plaque. Development of neointimal hyperplasia (NIH) following this pathophysiologic response is a function of inflammation caused by platelets, monocytes, macrophages, and lymphocytes, as well as rapid migration and proliferation of generally quiescent cells in the median layer of the artery wall. Conclusion: After damage to the artery wall, platelets play an essential role in the incidence of NIH by contributing to inflammation and migration of vascular smooth muscle cells and extracellular matrix remodeling, especially via secretion of different chemokines; therefore, developing therapeutic strategies for platelet inhibition in a controlled manner could be the basis of preventive treatments in the near future. In this study, for the first time, we hypothesize that evaluation of platelet activity profile in patients before and after stent implantation may determine the prognosis and likelihood of ISR.

In general, postmenopausal women present higher mortality, and worse prognosis after myocardial infarction (MI) compared to men, due to estrogen deficiency. After MI, cardiovascular alterations occur such as the autonomic imbalance and the pro-inflammatory cytokines increase. In this sense, therapies that aim to minimize deleterious effects caused by myocardial ischemia are important. Aerobic training has been proposed as a promising intervention in the prevention of cardiovascular diseases. On the other hand, some studies have attempted to identify potential biomarkers for cardiovascular diseases or specifically for MI. For this purpose, metabolomics has been used as a tool in the discovery of cardiovascular biomarkers. Therefore, the objective of this work is to discuss the changes involved in ovariectomy, myocardial infarction, and aerobic training, with emphasis on inflammation and metabolism.

Today, cardiovascular diseases remain a leading cause of morbidity and mortality worldwide. Endothelial to mesenchymal transition (EndMT) does not only play a major role in the course of development but also contributes to several cardiovascular diseases in adulthood. EndMT is characterized by down-regulation of the endothelial proteins and highly up-regulated fibrotic specific genes and extracellular matrix-forming proteins. EndMT is also a transforming growth factor- β-driven (TGF-β) process in which endothelial cells lose their endothelial characteristics and acquire a mesenchymal phenotype with expression of α-smooth muscle actin (α-SMA), fibroblastspecific protein 1, etc. EndMT is a vital process during cardiac development, thus disrupted EndMT gives rise to the congenital heart diseases, namely septal defects and valve abnormalities. In this review, we have discussed the main signaling pathways and mechanisms participating in the process of EndMT such as TGF-β and Bone morphogenetic protein (BMP), Wnt#, and Notch signaling pathway and also studied the role of EndMT in physiological cardiovascular development and pathological conditions including myocardial infarction, pulmonary arterial hypertension, congenital heart defects, cardiac fibrosis, and atherosclerosis. As a perspective view, having a clear understanding of involving cellular and molecular mechanisms in EndMT and conducting Randomized controlled trials (RCTs) with a large number of samples for involving pharmacological agents may guide us into novel therapeutic approaches of congenital disorders and heart diseases.

Background: Frequent premature ventricular contractions (PVC) can result in PVCinduced cardiomyopathy (PVC-iCMP), leading to reduced Left Ventricular Ejection Fraction (LVEF) that can be improved by radiofrequency catheter ablation (RFCA). We performed a systematic review to determine the variables predicting LVEF improvement after RFCA in PVCiCMP. Methods: We developed a “population, intervention, outcome and predictive factors” framework and searched MEDLINE, Embase, Cochrane Library, Cochrane Collaboration and Cochrane Database of Systematic Reviews (CDSR) for full-text, peer-reviewed publications. These publications addressing predictive factors of LVEF improvement showed ≥5% improvement only if deemed significant by the respective study, ≥10% or ≥ 50% after RFCA ablation in patients with PVCiCMP with no type/date/language limitation until the end of 2017. Results: Our initial search yielded 2226 titles, 1519 of which remained after removing the duplicates. Finally, 11 articles - 2 cohorts, 7 quasi-experimental studies, 1 case-control and 1 metaanalysis- were included. Sustained successful ablation, higher baseline PVC burden, LVEF, QRS duration, post-PVC systolic blood pressure rise and post-PVC pulse pressure change, the absence of an underlying cardiomyopathy, younger age, and variability of the frequency of PVCs during the day and lower left ventricular end-diastolic diameter (LVEDD) have been suggested as predictive factors for LVEF improvement in patients with PVC-iCMP. Conclusion: The mentioned factors may all be useful to identify PVC-iCMP patients who would benefit from RFCA, although the evidence is not yet strong enough.

Background: A grave complication of thyrotoxicosis, or thyroid storm, is the development of heart failure and cardiomyopathy. Recognizing this condition is imperative in preventing further left ventricular dysfunction and cardiogenic shock. This manuscript aims to review the literature on cardiogenic shock associated with thyrotoxicosis and present management recommendations on this rare condition. Methods: A literature search was performed in December of 2018, using the PubMed medical search engine. A systematic search was carried out using the keywords Thyroid Storm AND Cardiogenic Shock and Thyrotoxicosis AND Shock. Management: Decrease of thyroid hormone levels using therapeutic plasma exchange LV Unloading and ventilation by Impella and Extracorporeal Mechanical Ventilation (ECMO). Conclusion: Patients presenting with thyroid storm-induced shock may not be suitable candidates for traditional management with β -adrenergic blockers (β-blockers). The use of β-blockers could exasperate their condition. Through extensive literature review on this rare condition, the most effective management was found to be therapeutic plasma exchange in order to decrease thyroid hormone levels, which have direct toxic effect on the heart. Furthermore, the use of ECMO and Impella is advised to reduce pressure on the heart and ensure the patient’s organs are well oxygenated and perfused while the left ventricle is recovering.

Background: Systemic Mastocytosis (SM) is a disorder of excessive mast cell infiltration in multiple organ tissues. Atherosclerosis is a major risk factor for developing acute coronary syndrome. In addition to lipid accumulation in the arterial wall, inflammation plays an important role in the pathogenesis of plaque rupture and activating the thrombosis cascade. The Mast cells contribution to plaque destabilization has been well established in multiple animal and human studies. In a recent study, SM has been proven to be associated with a higher incidence of acute coronary syndrome even with lower plasma lipids levels. The study showed that 20% of patients with SM had cardiovascular events compared to only 6% in the control group with adjustment to all cardiac risk factors. Case: We presented a patient with no risk factors for heart disease other than old age and history of SM who developed acute myocardial infarction. Conclusion: SM can be life-threatening and can result in ACS, anaphylactic reaction, syncope, or cardiac arrest. Clinicians should have a high index of suspicion of acute coronary syndrome (ACS) occurrence in the setting of inflammatory conditions, such as SM and KS, and vice versa, where SM should be considered or ruled out in patients who suffer from anaphylaxis and cardiac arrest or myocardial infarction.

Symptoms of patients or the way of presenting complaints by the patients may be indefinite, obscure or misleading for the diagnosis of supraventricular tachycardia. The content of the history shows variability depending on the present symptoms, patient concerns and priority. Herein, an unusual case of a young woman suffering from chilling-like attacks for one and half years and treated by slow pathway ablation has been presented.

Introduction: Sleep-related problems like sleep apnea are increasing tremendously mostly owing to the disordered lifestyle the present generation is leading which is added like a topping on the base of obesity and metabolic syndrome. The burden on the society is huge taking into consideration the work-time loss and health-related financial issues arising out of these sleep disorders with obstructive sleep apnea (OSA) leading the way. Early diagnosis can prevent several complications of OSA. Cardiovascular diseases, including various arrhythmias, arising due to OSA, are described previously. Case Presentation: Herein, an interesting case of OSA, whose pacemaker installation to rectify the long pause could be avoided by simple correction of his OSA using continuous positive airway pressure, is presented. This 49-year-old male patient was diagnosed with severe OSA by using polysomnography and all his significant sinus pauses (highest one with 7.8 sec) during holter ECG monitoring were found to be occurring at night and correcting his OSA with continuous positive airway pressure (CPAP) treatment reverted all those sinus pauses and the need for any further intervention with pacemaker was discarded. Discussion: OSA is caused by either partial or complete obstruction of the upper airway, and there is the simultaneously attenuated upper airway dilator muscle tone while the patient is sleeping. The gold standard test designed for the assessment of OSA is polysomnography, as approved by the American Academy of Sleep Medicine and CPAP has been found to be universally beneficial in treating OSA related complications. Physiologically, the ACC/AHA guidelines recommend pacing only in patients with prolonged asymptomatic pauses occurring during wakefulness. This case report proved the above mentioned claim of CPAP treatment.

We present two patients who underwent cardiac surgery followed by post-operative low cardiac output, diastolic dysfunction and resistance to inotropic support. Despite aggressive medical management, both patients died. At autopsy, the hearts were enlarged and showed previously undiagnosed myocardial and vascular amyloidosis. Occult cardiac amyloidosis is an uncommon, often occult, contributor to post-operative complications post cardiac surgery. Pre-operative or intraoperative myocardial biopsy may be useful in patients with unexplained diastolic dysfunction. Brief Summary: We present two patients who underwent cardiac surgery followed by low cardiac output, diastolic dysfunction and resistance to inotropic support. Cardiac dysfunction was due to occult amyloidosis. Pre-operative or intra-operative myocardial biopsy may be useful in patients with unexplained diastolic dysfunction. With recent therapy advances, classification and possible treatment of amyloid are possible.