Abstract 110: Activation of the Homeostatic Intracellular Response Leads to Increased Myocardial Mitochondrial Turnover in Patients Undergoing Cardiac Surgery

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Allen M Andres ◽  
David Sengstock ◽  
Salik Jahania ◽  
Reza Dabir ◽  
Roberta A Gottlieb ◽  
...  

Background: Previously we showed that the homeostatic intracellular repair response (HIR2) is activated in the hearts of patients undergoing cardiac surgery. Autophagy is a principal component of this beneficial response that clears fragile mitochondria and protein aggregates. Moreover, we have previously shown that mitochondrial elimination through autophagy (mitophagy) is a key element in ischemic preconditioning. Thus, an important mechanism of cardioprotection appears to involve the upregulation of autophagy which facilitates the clearance of vulnerable mitochondria to limit I/R injury. We hypothesized that this protective action leads to turnover of the existing mitochondrial population in the heart during the resolution of I/R injury. The purpose of this study was to examine if the mechanism of HIR2 extends to remodeling the existing mitochondrial population of the heart. Study Design: Autophagy and mitochondrial turnover were assessed in 10 patients undergoing coronary artery bypass or valve surgery requiring cardiopulmonary bypass. Biopsies of the right atrial appendage obtained before initiation and after weaning from cardiopulmonary bypass were processed to yield whole tissue lysates and mitochondria-enriched heavy membrane fractions. Samples were analyzed for autophagy by immunoblotting for LC3, Beclin-1, ATG5-12, and p62. Mitochondrial turnover was assessed by monitoring Tom70, Cox4, Drp1, p62 and Parkin in tissue lysates and heavy membrane fractions. Results: Heart surgery was associated with a robust increase in autophagy indicated by depletion of LC3, Beclin-1, ATG5-12 and p62, as well as the mitophagy and fission regulator Drp1. Parkin increased in the mitochondrial fraction after bypass. Surprisingly, post-bypass tissue lysates showed a marked increase in mitochondrial markers Tom70 and Cox4, suggesting mitochondrial biogenesis. Conclusions: These findings provide evidence for the first time in humans that coordinated mitophagy and biogenesis are part of the homeostatic response to I/R, pointing to the importance of studying this aspect of HIR2. Strategies designed to amplify HIR2 during cardiac stress may represent an entirely new approach to myocardial protection in patients undergoing heart surgery.

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Salik Jahania ◽  
David Sengstock ◽  
Peter Vaitkevicius ◽  
Redah Mahmood ◽  
Fahed Sabagh ◽  
...  

Autophagy is an endogenous survival mechanism and adaptive response to cellular stress. We hypothesized that autophagy plays an important cardioprotective role in humans and would be accelerated during the ischemic stress of conventional heart surgery. In a prospective study to test this hypothesis, we measured key autophagy proteins (Beclin-1, Atg5-12, p62) in cardiac tissue from 5 patients undergoing cardiac surgery. Right atrial biopsies were obtained before and after cessation of cardiopulmonary bypass (CPB). In 4 of these patients, CPB was associated with a marked decrease in cardiac Beclin-1, Atg5-12, and p62. We believe that depletion of these factors, particularly p62, reflects a brisk increase in autophagic flux (Fig. 1). In one patient (#02), autophagic flux appeared to be impaired. This occurred in an aged patient with characteristics of metabolic syndrome (MetS) who had the highest predicted operative morbidity/mortality. While the number of patients studied is small and insufficient to reach any definitive conclusions, these preliminary data confirm the feasibility of studying autophagy in the human heart and suggest that ischemic stress during heart surgery is associated with a marked upregulation of autophagic flux. A better understanding of the role of autophagy could lead to the development of new cardioprotective strategies. [Figure 1: Changes in cardiac autophagy proteins in patients undergoing heart surgery before and after cross-clamping the aorta (after restoration of myocardial blood flow).]


2021 ◽  
Author(s):  
Rupesh Kumar ◽  
Vidur Bansal ◽  
Subhendu Mahapatra ◽  
Gautam Sengupta

Abstract Myocardial ischemia is a metabolic phenomenon that occurs in patients undergoing open heart surgery like coronary artery bypass grafting (CABG), valvular heart surgery, vascular surgeries etc., due to stress imposed during cardiopulmonary bypass (CPB), obligatory interruption of coronary blood flow during aortic cross clamp and reperfusion after aortic cross clamp release. The present study is designed to have a detailed study on estimation of coronary sinus lactate and troponin t levels in patients undergoing cardiac surgery with cardiopulmonary bypass and its correlation with various parameters related to the perioperative outcomes.


2012 ◽  
Vol 15 (2) ◽  
pp. 84 ◽  
Author(s):  
Canturk Cakalagaoglu ◽  
Cengiz Koksal ◽  
Ayse Baysal ◽  
Gokhan Alici ◽  
Birol Ozkan ◽  
...  

<p><b>Aim:</b> The goal was to determine the effectiveness of the posterior pericardiotomy technique in preventing the development of early and late pericardial effusions (PEs) and to determine the role of anxiety level for the detection of late pericardial tamponade (PT).</p><p><b>Materials and Methods:</b> We divided 100 patients randomly into 2 groups, the posterior pericardiotomy group (n = 50) and the control group (n = 50). All patients undergoing coronary artery bypass grafting surgery (CABG), valvular heart surgery, or combined valvular and CABG surgeries were included. The posterior pericardiotomy technique was performed in the first group of 50 patients. Evaluations completed preoperatively, postoperatively on day 1, before discharge, and on postoperative days 5 and 30 included electrocardiographic study, chest radiography, echocardiographic study, and evaluation of the patient's anxiety level. Postoperative causes of morbidity and durations of intensive care unit and hospital stays were recorded.</p><p><b>Results:</b> The 2 groups were not significantly different with respect to demographic and operative data (<i>P</i> > .05). Echocardiography evaluations revealed no significant differences between the groups preoperatively; however, before discharge the control group had a significantly higher number of patients with moderate, large, and very large PEs compared with the pericardiotomy group (<i>P</i> < .01). There were 6 cases of late PT in the control group, whereas there were none in the pericardiotomy group (<i>P</i> < .05). Before discharge and on postoperative day 15, the patients in the pericardiotomy group showed significant improvement in anxiety levels (<i>P</i> = .03 and .004, respectively). No differences in postoperative complications were observed between the 2 groups.</p><p><b>Conclusion:</b> Pericardiotomy is a simple, safe, and effective method for reducing the incidence of PE and late PT after cardiac surgery. It also has the potential to provide a better quality of life.</p>


Author(s):  
Lauren R. Kennedy-Metz ◽  
Roger D. Dias ◽  
Rithy Srey ◽  
Geoffrey C. Rance ◽  
Heather M. Conboy ◽  
...  

Objective This novel preliminary study sought to capture dynamic changes in heart rate variability (HRV) as a proxy for cognitive workload among perfusionists while operating the cardiopulmonary bypass (CPB) pump during real-life cardiac surgery. Background Estimations of operators’ cognitive workload states in naturalistic settings have been derived using noninvasive psychophysiological measures. Effective CPB pump operation by perfusionists is critical in maintaining the patient’s homeostasis during open-heart surgery. Investigation into dynamic cognitive workload fluctuations, and their relationship with performance, is lacking in the literature. Method HRV and self-reported cognitive workload were collected from three Board-certified cardiac perfusionists ( N = 23 cases). Five HRV components were analyzed in consecutive nonoverlapping 1-min windows from skin incision through sternal closure. Cases were annotated according to predetermined phases: prebypass, three phases during bypass, and postbypass. Values from all 1min time windows within each phase were averaged. Results Cognitive workload was at its highest during the time between initiating bypass and clamping the aorta (preclamp phase during bypass), and decreased over the course of the bypass period. Conclusion We identified dynamic, temporal fluctuations in HRV among perfusionists during cardiac surgery corresponding to subjective reports of cognitive workload. Not only does cognitive workload differ for perfusionists during bypass compared with pre- and postbypass phases, but differences in HRV were also detected within the three bypass phases. Application These preliminary findings suggest the preclamp phase of CPB pump interaction corresponds to higher cognitive workload, which may point to an area warranting further exploration using passive measurement.


Trials ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Thiago Augusto Azevedo Maranhão Cardoso ◽  
Gudrun Kunst ◽  
Caetano Nigro Neto ◽  
José de Ribamar Costa Júnior ◽  
Carlos Gustavo Santos Silva ◽  
...  

Abstract Background Recent experimental evidence shows that sevoflurane can reduce the inflammatory response during cardiac surgery with cardiopulmonary bypass. However, this observation so far has not been assessed in an adequately powered randomized controlled trial. Methods We plan to include one hundred patients undergoing elective coronary artery bypass graft with cardiopulmonary bypass who will be randomized to receive either volatile anesthetics during cardiopulmonary bypass or total intravenous anesthesia. The primary endpoint of the study is to assess the inflammatory response during cardiopulmonary bypass by measuring PMN-elastase serum levels. Secondary endpoints include serum levels of other pro-inflammatory markers (IL-1β, IL-6, IL-8, TNFα), anti-inflammatory cytokines (TGFβ and IL-10), and microRNA expression in peripheral blood to achieve possible epigenetic mechanisms in this process. In addition clinical endpoints such as presence of major complications in the postoperative period and length of hospital and intensive care unit stay will be assessed. Discussion The trial may determine whether adding volatile anesthetic during cardiopulmonary bypass will attenuate the inflammatory response. Trial registration ClinicalTrials.gov NCT02672345. Registered on February 2016 and updated on June 2020.


2010 ◽  
Vol 17 (01) ◽  
pp. 55-58
Author(s):  
ZAHID PARVEZ ◽  
FARID AHMAD CHAUDHARY ◽  
AJMAL HASAN NAZQVI ◽  
Muniza Saeed

Placement of epicardial wires on the right atrial and right ventricle surfaces is a routine practice in cardiac surgery. These pacingelectrodes are used for invasive pacing of the myocardium for a variety of emergent and elective conditions postoperatively. There is uncertaintyin actual practice about the optimum time for their removal, and practice varies widely between different institutions. Objectives: To determine thetime related efficacy of these pacing electrodes after cardiac surgery, to find out the optimum time of their removal. Period: July 2008 toOctober 2008. Patients & Methods: 47 patients those underwent coronary artery bypass surgery were prospectively enrolled and evaluatedwith standard 12 lead ECG and ventricle pacing threshold immediately after surgery and on the 5t h postoperative day. The patients were dividedinto two subgroups according to their left ventricle ejection fraction ( > 40% verses < 40%). Results: There was significant difference in theeffective pacing threshold in groupl and 2 on immediate post operative period and on day 5. (P = 0.002 and P = 0.02 respectively) The sensingthreshold immediately after operation and on 5t h post operative day also differed significantly (P = 0.009 in group 1 and 0.02 in group 2) Theeffective VVI* pacing was lost in 17 patients (40.5%) on the 5t h post operative day and comparison of effective pacing threshold in the twogroups showed no significant difference during the same period of time (P = NS). "Ventrculo-ventrical inhibition. Conclusions: The epicardialpacing wires have little usefulness after the fifth postoperative day and should be removed by this time. In addition postoperative pacingthreshold was not affected by the decreased left ventricular function.


2019 ◽  
Vol 6 (3) ◽  
pp. 756
Author(s):  
Praveen Dhaulta ◽  
Vikas Panwar

Background: Acute kidney injury (AKI) is one of the most serious complications during the postoperative period of cardiac surgery. Multiple variables predict the ARF after cardiac surgery. Objective of this study was to evaluate the significance of pre and peri-operative variables which may help in predicting the chances of developing ARF after cardiac surgery.Methods: This study was an observational, prospective study conducted among patients who were scheduled to undergo open heart surgery under cardiopulmonary bypass.Results: In total, 50 patients who underwent open-heart surgery, ARF was seen in 5 patients, with the incidence rate of 10%. Acute renal failure was present in one patient with ejection fraction <35, 2 patients had ejection fraction between 35 to 50 and 2 patients with ejection fraction >50. It was seen in 4 patients with 1-2 hrs of cardiopulmonary bypass and in 1 patient with >2 hrs of cardiopulmonary bypass. ARF was also seen in 4 patients with hematocrit between 22-26% and in 1 patient with >26%.Conclusions: The study provided a clinical variable score that can predict ARF after open-heart surgery. The score enhances the accuracy of prediction by accounting for the effect of all major risk factors of ARF.


2020 ◽  
Vol 13 (Suppl_1) ◽  
Author(s):  
Karol Quelal ◽  
Olakanmi Olagoke ◽  
Jose Baez

Introduction: Significant atrioventricular blocks and bradyarrhythmias are known complications of open-heart surgery. These are frequently transient, however, some patients go on to need a permanent pacemaker (PP). We sought to describe the incidence, predictors, and outcomes of PP implantation among patients admitted for cardiac surgery who develop bradyarrhythmias. Methods: We queried the National Inpatient Sample (NIS) database from 2010 to 2014 for adults admitted for surgical valve replacement, valvuloplasty or coronary artery bypass grafting (CABG) who had bradyarrhythmias during the admission using the appropriate ICD codes. We identified patients who had permanent pacemaker implantation documented during the admission. Categorical and continuous variables were compared using the chi-square and student's t-test. Predictors of PP implantation and in-hospital mortality were evaluated by logistic regression. Results: Of the 1402930 patients who underwent cardiac surgery, 94748 patients had bradyarrhythmias defined as sinoatrial node dysfunction (SND) and/or atrioventricular block (AVB) during hospitalization. The primary procedure was identified as valve replacement in 50.3% (47615 of 94748), CABG in 29.9% (27622 of 94748) and valvuloplasty in 8.7% (8248 of 94748). SND was found in 29.9% (28372 of 94748) and AVB in 76% (72017 of 94748). Permanent pacemaker implantation was done in 39.3% (37246 of 94748). Valve replacement was the most common surgery associated with PP implantation [58% (21682 of 37246) compared to 21.5% in CABG (8007 of 37246) and 7.7% in valvuloplasty (2882 of 37246), p < 0.001). Female sex aOR 1.36 (95% CI 1.31 - 1.40), young age 18 - 44 years aOR 1.36 (95% CI 1.24 - 1.49), Asiatic and Hispanic origin aOR 1.36 (95% CI 1.23 - 1.51), aOR 1.25 (95% CI 1.17 - 1.34) respectively, diabetes mellitus with chronic complications aOR 1.16 (95% CI 1.09 - 1.24), drug abuse aOR 1.38 (95% CI 1.21 - 1.55) were associated with higher odds of pacemaker implantation. African American origin aOR 0.79 (95CI 0.74 - 0.85), AIDS aOR 0.33 (95% CI 0.17 - 0.67), south hospital region aOR 0.89 (95% CI 0.85 - 0.93), no-charge admissions aOR 0.66 (95% CI 0.49 - 0.89) were associated with a lower odds of PPM implantation. Death during hospitalization was found in 3% of the patients. After multivariable regression, PP implantation was associated with a lower likelihood of in-hospital death aOR 0.45 (95% CI 0.41 - 0.50). Conclusion: Approximately one-third of the patients hospitalized for cardiac surgery related to AVB and/or SND were implanted a permanent pacemaker. Factors like age, sex, race and comorbidities determine the likelihood of this procedure that has a significant impact on mortality. Having a better insight into these predictors would allow a better triage of patients who would benefit from its implantation.


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