Role of Neuropeptide Y and Peroxisome Proliferator-activated Receptor γ Coactivator-1α in Stress Cardiomyopathy

Death following situations of intense emotional stress has been linked to the cardiac pathology described as stress cardiomyopathy, whose pathomechanism is still not clear. In this study, we sought to determine, via an animal model, whether the transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α) and the amino peptide neuropeptide Y (NPY) play a role in the pathogenesis of this cardiac entity. Male Sprague-Dawley rats in the experimental group were subjected to immobilization in a plexy glass box for 1 h, which was followed by low voltage elec-tric foot shock for about 1h at 10s intervals in a cage fitted with metallic rods. After 25 days the rats were sacrificed and sections of their hearts were processed. Hematoxylin-eosin staining of cardiac tissues revealed the characteristic cardiac lesions of stress cardiomyopathy such as contraction band necrosis, inflammatory cell infiltration and fibrosis. The semi-quantitative RT-PCR analysis for PGC-1α mRNA expression showed significant overexpression of PGC1-α in the stress-subjected rats (P<0.05). Fluorescence immunohistochemistry revealed a higher production of NPY in the stress-subjected rats as compared to the control rats (P=0.0027). Thus, we are led to conclude that following periods of intense stress, an increased expression of PGC1-α in the heart and an overflow of NPY may lead to stress car-diomyopathy and even death in susceptible victims. Moreover, these markers can be used to identify stress cardiomyopathy as the cause of sudden death in specific cases.

Stress cardiomyopathy in critical care:A case series of 109 patients

BACKGROUND Critically ill patients are at risk of developing stress cardiomyopathy(SC)but can be under-recognized.AIM To describe a case series of patients with SC admitted to critical care units.METHODS We conducted a retrospective observational study at a tertiary care teaching hospital.All adult(≥18 years old)patients admitted to the critical care units with stress cardiomyopathy over 5 years were included.RESULTS Of 24279 admissions to the critical care units[19139 to medical-surgical intensive care units(MSICUs)and 5140 in coronary care units(CCUs)],109 patients with SC were identified.Sixty(55%)were admitted to the coronary care units(CCUs)and forty-nine(45%)to the medical-surgical units(MSICUs).The overall incidence of SC was 0.44%,incidence in CCU and MSICU was 1.16%and 0.25%respectively.Sixty-two(57%)had confirmed SC and underwent cardiac catheterization whereas 47(43%)had clinical SC,and did not undergo cardiac catheterization.Forty-three(72%)patients in the CCUs were diagnosed with primary SC,whereas all(100%)patients in MSICUs developed secondary SC.Acute respiratory failure that required invasive mechanical ventilation and shock developed in twenty-nine(59%)MSICU patients.There were no statistically significant differences in intensive care unit(ICU)mortality,in-hospital mortality,use of inotropic or mechanical circulatory support based on type of unit or anatomical variant.CONCLUSION Stress cardiomyopathy can be under-recognized in the critical care setting.Intensivists should have a high index of suspicion for SC in patients who develop sudden or worsening unexplained hemodynamic instability,arrhythmias or respiratory failure in ICU.

Aortic Stenosis and Stressed Heart Morphology

Myocardial geometric remodeling is a response to increased stress which includes increased afterload situations during clinical conditions. In this review, we have focused on early and late geometric features in aortic stenosis, importance of recognition of these findings and consequences due to progression of valve disease. We have also pointed out the similarities in early focal and global myocardial geometric remodeling in acute and chronic conditions as hypertension and acute stress cardiomypathy which are associated with myocardial functional and geometric response to acute or chronic stress exposure and relevant increased afterload. In aortic stenosis, target organ involvement in disease progression has been evaluated and discussed in the report. In addition to quantitative evaluation of valve disease, importance of myocardial involvement and global assessment of patients with aortic stenosis also have been mentioned in the report. Finally, we have discussed the importance of global myocardial geometric changes and timing for surgery before development of heart failure in this specific group of patients.

Cardiovascular complications following medical termination of pregnancy: An updated review

BACKGROUND Around 1 million cases of medical termination of pregnancy(MTP)take place yearly in the United States of America with around 2 percent of this population developing complications.The cardiovascular(CVD)complications occurring post MTP or after stillbirth is not very well described.AIM To help the reader better understand,prepare,and manage these complications by reviewing various cardiac comorbidities seen after MTP.METHODS We performed a literature search in PubMed,Medline,RCA,and google scholar,using the search terms“abortions”or“medical/legal termination of pregnancy”and“cardiac complications”or“cardiovascular complications”.RESULTS The most common complications described in the literature following MTP were infective endocarditis(IE)(n=16),takotsubo cardiomyopathy(TTC)(n=7),arrhythmias(n=5),and sudden coronary artery dissection(SCAD)(n=4).The most common valve involved in IE was the tricuspid valve in 69%(n=10).The most observed causative organism was group B Streptococcus in 81%(n=12).The most common type of TTC was apical type in 57%(n=4).Out of five patients de veloping arrhythmia,bradycardia was the most common and was seen in 60%(3/5)of the patients.All four cases of SCAD-P type presented as acute coronary syndrome 10-14 d post termination of pregnancy with predominant involvement of the right coronary artery.Mortality was only reported following IE in 6.25%.Clinical recovery was reported consistently after optimal medical management following all these complications.CONCLUSION In conclusion,the occurrence of CVD complications following pregnancy termination is infrequently documented in the existing literature.In this review,the most common CVD complication following MTP was noted to be IE and TTC.

Acute myocardial injury in patients with COVID-19:Possible mechanisms and clinical implications

Severe acute respiratory syndrome coronavirus 2 infection affects not only the lungs,but also the cardiovascular system,having a major impact on patients’outcomes.Myocardial injury(MI)occurs in the context of coronavirus infectious disease 2019(COVID-19)and is associated with a higher risk of severe clinical outcome and mortality.COVID-19-related MI can have various clinical manifestations,of which the main ones are myocarditis,stress cardiomyopathy,acute coronary syndrome,and pulmonary embolism.The exact mechanisms of how MI occurs in these patients are not yet fully known.Direct injury,through direct viral myocardial invasion,and indirect injury,through interaction with angiotensin I converting enzyme 2,increased inflammation,and thrombocyte and endothelial dysfunction,could be involved in acute MI in patients with COVID-19.A better understanding of these multiple potential mechanisms may help to develop new targeted therapeutic strategies.The purpose of this review is to provide the current understanding of the potential mechanisms involved in MI induced by COVID-19 and to discuss the current progress in the therapeutic strategies.

Diffuse coronary artery vasospasm in a patient with subarachnoid hemorrhage: A case report

BACKGROUND Coronary artery vasospasm(CAV)is a reversible,transient form of vasoconstriction with clinical manifestations ranging from stable angina to acute coronary syndromes(ACS).Vasospasm of epicardial coronary arteries or associated micro-vasculature can lead to total or subtotal occlusion and has been demonstrated in nearly 50%of patients undergoing angiography for suspected ACS.The mechanism for CAV has been described in literature,but in a subgroup of patients presenting with intracranial hemorrhage,it appears to be multifactorial.These patients tend to have electrocardiographic changes,elevation of cardiac biomarkers of injury and neurogenic stress cardiomyopathy.CASE SUMMARY A 44-year-old woman presented with severe headaches and tonic-clonic seizures.She was found to have diffuse subarachnoid hemorrhage(SAH)requiring ventricular drain placement,coil embolization and induced hypertension.She subsequently developed chest pain with ST elevations in anterior precordial leads,elevated cardiac enzymes and apical ballooning with left ventricular ejection fraction of 35%on transthoracic echocardiogram.Coronary angiogram revealed severe diffuse triple vessel stenoses secondary to CAV seen distally.Subsequent cardiac MRI notable for apical non-viability and scar formation.CONCLUSION This case highlights a unique etiology of acute myocardial infarction in a patient with SAH leading to ST elevations,diffuse triple vessel CAV and apical scar.