Potassium and Cardiac Surgery

2021 ◽  
Author(s):  
Shawn Kant ◽  
Frank W. Sellke ◽  
Jun Feng

Potassium homeostasis affects cardiac rhythm and contractility, along with vascular reactivity and vascular smooth muscle proliferation. This chapter will focus on potassium dynamics during and after cardiac surgery involving cardioplegic arrest and cardiopulmonary bypass (CPB). Hyperkalemic, hypothermic solutions are frequently used to induce cardioplegic arrest and protect the heart during cardiac surgery involving CPB. Common consequences of hyperkalemic cardioplegic arrest and reperfusion include microvascular dysfunction involving several organ systems and myocardial dysfunction. Immediately after CPB, blood potassium levels often drop precipitously due to a variety of factors, including CPB -induced electrolyte depletion and frequent, long-term administration of insulin during and after surgery. Meanwhile, some patients with pre-existing kidney dysfunction may experience postoperative hyperkalemia following cardioplegia. Any degree of postoperative hyper/hypokalemia significantly elevates the risk of cardiac arrythmias and subsequent myocardial failure. Therefore, proper management of blood potassium levels during and after cardioplegia/CPB is crucial for optimizing patient outcomes following cardiac surgery.

2020 ◽  
Vol 75 (5S) ◽  
pp. 414-425
Author(s):  
Olga S. Oynotkinova ◽  
Evgenii L. Nikonov ◽  
Oleg V. Zayratyants ◽  
Elena V. Rzhevskaya ◽  
Evgenii V. Krukov ◽  
...  

In a review article based on my own clinical experience of managing patients with acute myocardial injury and fulminant myocarditis, taking into account expert recommendations on the clinical treatment of myocardial damage associated with novel coronavirus infection a National clinical geriatric medical research center, division of cardiovascular diseases, the Chinese geriatrics society, Department of cardiology, Beijing Medical Association and European clinics discusses the pathogenesis, diagnosis and treatment of myocardial damage and FM patients, infected with SARS-CoV-2 in the context of the COVID-19 pandemic. Clinical features and diagnostic criteria are presented, including screening tests of markers of myocardial damage in the form of a highly sensitive troponin test, a natriuretic peptide. The article discusses in detail the pathogenesis and mechanisms of myocardial damage, including immune mechanisms, cytokine storm, systemic inflammation with macro- and microvascular dysfunction and the development of myocardial dysfunction with acute heart failure, hypotension, cardiogenic shock and/or life-threatening heart rhythm disorders caused by hypoxia and metabolic disorders at the cellular level. Features of the clinical course of fulminant myocarditis in infected patients (SARS-CoV-2) in the conditions of the COVID-19 pandemic are presented. For the first time, a detailed histo-morphological analysis of pathological myocardial injuries and complications is presented on the basis of unique autopsy material on post-mortem diagnostics of various pathoanatomic autopsies of those who died from COVID-19 in Moscow. Based on the clinical, functional and morphological material, the Protocol of etiopathogenetic treatment is presented. The basis of standard therapy is considered antiviral drugs, immunoglobulin G, the use of monoclonal antibodies to interleukin-6, anticoagulants, glucocorticoids, depending on the clinical situation, cardioprotectors and symptomatic treatment are recommended to maintain the heart, which in combination can achieve a certain clinical effectiveness. As adjuvant cardioprotective targeted therapy, the sodium salt of phosphocreatine is considered in order to preserve the myocardium, maintain its contractility and vital activity.


2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Marieke E. van Vessem ◽  
Saskia L. M. A. Beeres ◽  
Rob B. P. de Wilde ◽  
René de Vries ◽  
Remco R. Berendsen ◽  
...  

Abstract Background Vasoplegia is a severe complication which may occur after cardiac surgery, particularly in patients with heart failure. It is a result of activation of vasodilator pathways, inactivation of vasoconstrictor pathways and the resistance to vasopressors. However, the precise etiology remains unclear. The aim of the Vasoresponsiveness in patients with heart failure (VASOR) study is to objectify and characterize the altered vasoresponsiveness in patients with heart failure, before, during and after heart failure surgery and to identify the etiological factors involved. Methods This is a prospective, observational study conducted at Leiden University Medical Center. Patients with and patients without heart failure undergoing cardiac surgery on cardiopulmonary bypass are enrolled. The study is divided in two inclusion phases. During phase 1, 18 patients with and 18 patients without heart failure are enrolled. The vascular reactivity in response to a vasoconstrictor (phenylephrine) and a vasodilator (nitroglycerin) is assessed in vivo on different timepoints. The response to phenylephrine is assessed on t1 (before induction), t2 (before induction, after start of cardiotropic drugs and/or vasopressors), t3 (after induction), t4 (15 min after cessation of cardiopulmonary bypass) and t5 (1 day post-operatively). The response to nitroglycerin is assessed on t1 and t5. Furthermore, a sample of pre-pericardial fat tissue, containing resistance arteries, is collected intraoperatively. The ex vivo vascular reactivity is assessed by constructing concentrations response curves to various vasoactive substances using isolated resistance arteries. Next, expression of signaling proteins and receptors is assessed using immunohistochemistry and mRNA analysis. Furthermore, the groups are compared with respect to levels of organic compounds that can influence the cardiovascular system (e.g. copeptin, (nor)epinephrine, ANP, BNP, NTproBNP, angiotensin II, cortisol, aldosterone, renin and VMA levels). During inclusion phase 2, only the ex vivo vascular reactivity test is performed in patients with (N = 12) and without heart failure (N = 12). Discussion Understanding the difference in vascular responsiveness between patients with and without heart failure in detail, might yield therapeutic options or development of preventive strategies for vasoplegia, leading to safer surgical interventions and improvement in outcome. Trial registration The Netherlands Trial Register (NTR), NTR5647. Registered 26 January 2016.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Andreas Boening ◽  
Maximilian Hinke ◽  
Martina Heep ◽  
Kerstin Boengler ◽  
Bernd Niemann ◽  
...  

Abstract Background Because hearts in acute myocardial infarction are often prone to ischemia-reperfusion damage during cardiac surgery, we investigated the influence of intracellular crystalloid cardioplegia solution (CCP) and extracellular blood cardioplegia solution (BCP) on cardiac function, metabolism, and infarct size in a rat heart model of myocardial infarction. Methods Following euthanasia, the hearts of 50 rats were quickly excised, cannulated, and inserted into a blood-perfused isolated heart apparatus. A regional myocardial infarction was created in the infarction group (18 hearts) for 120 min; the control group (32 hearts) was not subjected to infarction. In each group, either Buckberg BCP or Bretschneider CCP was administered for an aortic clamping time of 90 min. Functional parameters were recorded during reperfusion: coronary blood flow, left ventricular developed pressure (LVDP) and contractility (dp/dt max). Infarct size was determined by planimetry. The results were compared between the groups using analysis of variance or parametric tests, as appropriate. Results Cardiac function after acute myocardial infarction, 90 min of cardioplegic arrest, and 90 min of reperfusion was better preserved with Buckberg BCP than with Bretschneider CCP relative to baseline (BL) values (LVDP 54 ± 11% vs. 9 ± 2.9% [p = 0.0062]; dp/dt max. 73 ± 11% vs. 23 ± 2.7% [p = 0.0001]), whereas coronary flow was similarly impaired (BCP 55 ± 15%, CCP 63 ± 17% [p = 0.99]). The infarct in BCP-treated hearts was smaller (25% of myocardium) and limited to the area of coronary artery ligation, whereas in CCP hearts the infarct was larger (48% of myocardium; p = 0.029) and myocardial necrosis was distributed unevenly to the left ventricular wall. Conclusions In a rat model of acute myocardial infarction followed by cardioplegic arrest, application of BCP leads to better myocardial recovery than CCP.


2016 ◽  
Vol 25 (8) ◽  
pp. e114
Author(s):  
John-Paul Tantiongco ◽  
Craig Bradbrook ◽  
Angela Walls ◽  
Joseph Selvanayagam

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Jo M. Zelis ◽  
Pim A. L. Tonino ◽  
Nico H. J. Pijls ◽  
Bernard De Bruyne ◽  
Richard L. Kirkeeide ◽  
...  

With the increasing prevalence of aortic stenosis (AS) due to a growing elderly population, a proper understanding of its physiology is paramount to guide therapy and define severity. A better understanding of the microvasculature in AS could improve clinical care by predicting left ventricular remodeling or anticipate the interplay between epicardial stenosis and myocardial dysfunction. In this review, we combine five decades of literature regarding microvascular, coronary, and aortic valve physiology with emerging insights from newly developed invasive tools for quantifying microcirculatory function. Furthermore, we describe the coupling between microcirculation and epicardial stenosis, which is currently under investigation in several randomized trials enrolling subjects with concomitant AS and coronary disease. To clarify the physiology explained previously, we present two instructive cases with invasive pressure measurements quantifying coexisting valve and coronary stenoses. Finally, we pose open clinical and research questions whose answers would further expand our knowledge of microvascular dysfunction in AS. These trials were registered with NCT03042104, NCT03094143, and NCT02436655.


2011 ◽  
Vol 300 (5) ◽  
pp. H1669-H1677 ◽  
Author(s):  
Richard T. Clements ◽  
Jun Feng ◽  
Brenda Cordeiro ◽  
Cesario Bianchi ◽  
Frank W. Sellke

We previously demonstrated that myocardial p38 mitogen-activated protein kinase (MAPK) and heat shock protein 27 (HSP27) are phosphorylated following cardioplegic arrest in patients undergoing cardiac surgery and correlate with reduced cardiac function. The following studies were performed to determine whether inhibition of p38 MAPK and/or overexpression of nonphosphorylatable HSP27 improves cardiac function following cardioplegic arrest. Langendorff-perfused isolated rat hearts were subjected to 2 h of intermittent cold cardioplegia followed by 30 min of reperfusion. Hearts were treated with (CP+SB) or without (CP) the p38 MAPK inhibitor SB-203580 (5 μM) supplied in the cardioplegia. Sham-treated hearts served as controls. In separate experiments, isolated rat ventricular myocytes infected with either green fluorescent protein (GFP) or a nonphosphorylatable HSP27 mutant (3A-HSP27) were subjected to 3 h of cold hypoxic cardioplegia and simulated reperfusion (CP) followed by video microscopy and length change measurements. Baseline parameters of cardiac function were similar between groups [left ventricular developed pressure (LVDP), 119 ± 4.9 mmHg; positive and negative first derivatives of LV pressure (± dP/d t), 3,139 ± 245 and 2, 314 ± 110 mmHg/s]. CP resulted in reduced cardiac function (LVDP, 72.2 ± 5.8 mmHg; ± dP/d t, 2,076 ± 231 and −1,317 ± 156 mmHg/s) compared with baseline. Treatment with 5 μM SB-203580 significantly improved CP-induced cardiac function (LVDP, 101.9 ± 0 mmHg; ±dP/d t, 2,836 ± 163 and −2,108 ± 120 mmHg/s; P = 0.03, 0.01, and 0.04, CP+SB vs. CP). Inhibition of p38 MAPK significantly lowered CP-induced p38 MAPK, HSP27, and αB-crystallin (cryAB) phosphorylation. In vitro CP decreased myocyte length changes from 10.3 ± 1.5% (GFP) to 5.7 ± 0.8% (GFP+CP). Infection with 3A-HSP27 completely rescued CP-induced decreased myocyte contraction (11.1 ± 1.0%). However, infection with 3A-HSP27 did not block the endogenous HSP27 response. We conclude that inhibition of p38 MAPK and subsequent HSP27 and cryAB phosphorylation and/or overexpression of nonphosphorylatable HSP27 significantly improves cardiac performance following cardioplegic arrest. Modulation of HSP27 phosphorylation may improve myocardial stunning following cardiac surgery.


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