Study of the factors related to atrial fibrillation after coronary artery bypass grafting: A search for a marker to predict the occurrence of atrial fibrillation before surgical intervention

ObjectiveAtrial fibrillation after cardiac surgery is a frequent complication. In this study we studied various factors in addition to trying to identify a marker that would predict the potential for atrial fibrillation before surgical intervention to prevent its occurrence.MethodsWe targeted 234 cases in which isolated coronary artery bypass grafting had been performed. The items for study included age, EuroSCORE, and maximum values of creatine phosphokinase–MB, troponin I, and angiotensin II after surgical intervention and preoperative values of atrial natriuretic peptide, brain natriuretic peptide, and C-reactive protein. As fibrotic markers, we measured levels of the sialylated carbohydrate antigen KL-6 in the blood, hyaluronic acid, and pyridinoline cross-linked carboxyterminal telepeptide of type I collagen C. At the time of surgical intervention, a section of the right atrium was extracted, and atrial natriuretic peptide, the sialylated carbohydrate antigen KL-6, hyaluronic acid, and pyridinoline cross-linked telopeptide of type I collagen levels were measured.ResultsAtrial fibrillation was observed in 73 (31.2%) cases, and preoperative factors that showed statistically significant differences in the occurrence of atrial fibrillation included age, EuroSCORE, and preoperative values of atrial natriuretic peptide, angiotensin II, the sialylated carbohydrate antigen KL-6, hyaluronic acid, and pyridinoline cross-linked telopeptide of type I collagen in the blood. As for intraoperative and postoperative factors, statistically significant differences were observed in the postoperative maximum of angiotensin II, atrial natriuretic peptide of the right atrium, the sialylated carbohydrate antigen KL-6, hyaluronic acid, and pyridinoline cross-linked telopeptide of type I collagen levels.ConclusionThe fibrosis of tissue associated with age is believed to be closely related to the occurrence of atrial fibrillation after coronary artery bypass grafting. This study suggests that the preoperative values of atrial natriuretic peptide, angiotensin II, the sialylated carbohydrate antigen KL-6, hyaluronic acid, and pyridinoline cross-linked telopeptide of type I collagen in the blood are useful as a new index for the occurrence of atrial fibrillation after coronary artery bypass grafting

Electrical storm after cardiac resynchronization therapy in a patient with nonischemic cardiomyopathy: Signal-averaged vector-projected 187-channel electrocardiogram-based risk stratification for lethal arrhythmia

AbstractWe describe treatment of atrial flutter and electrical storm presenting as incessant ventricular tachycardia (VT) after implantation of a cardiac resynchronization therapy defibrillator (CRT-D) in a patient with dilated cardiomyopathy. No prior arrhythmic event had occurred. Our treatment strategy, including amiodarone administration, was guided in part by signal-averaged vector-projected 187-channel electrocardiogram (SAVP-ECG)-based risk stratification for ventricular arrhythmia. Corrected recovery time (RTc) dispersion and Tpeak-end dispersion were used to evaluate transmural dispersion of repolarization. RTc and Tpeak-end dispersion increased during the period of electrical storm. Values were improved 2 years after CRT-D implantation, and the amiodarone was discontinued. The VT has not recurred despite discontinuation of the antiarrhythmic agent. SAVP-ECG-based risk stratification for ventricular arrhythmia proved useful for the management of antiarrhythmic therapy

Mid-Ventricular Obstructive Hypertrophic Cardiomyopathy Associated with an Apical Aneurysm: Evaluation of Possible Causes of Aneurysm Formation

Mid-ventricular obstructive hypertrophic cardiomyopathy (MVOHCM) is a rare type of cardiomyopathy, associated with apical aneurysm formation in some cases. We report a patient presenting with ventricular fibrillation, an ECG with an above normal ST segment, and elevated levels of cardiac enzymes but normal coronary arteries. Left ventriculography revealed a left ventricular obstruction without apical aneurysm. There was a significant pressure gradient between the apical and basal sites of the left ventricle. Cine magnetic resonance imaging (MRI), performed on the 10th hospital day, showed asymmetric septal hypertrophy, mid-ventricular obstruction, and an apical aneurysm with a thrombus. The first evaluation by contrast-enhanced imaging showed a subendocardial perfusion defect and delayed enhancement. It was speculated that the intraventricular pressure gradient, due to mid-ventricular obstruction, triggered myocardial infarction, which subsequently resulted in apical aneurysm formation

The Impact of Tofogliflozin on Physiological and Hormonal Function, Serum Electrolytes, and Cardiac Diastolic Function in Elderly Japanese Patients with Type 2 Diabetes Mellitus

The sodium glucose transporter 2 (SGLT2) inhibitor tofogliflozin is a glucose-lowering drug that causes the excretion of surplus glucose by inhibiting SGLT2. Because of tofogliflozin’s osmotic diuresis mechanism, patients’ serum electrolytes, body fluid levels, and cardiac function must be monitored. We retrospectively analyzed the cases of 64 elderly Japanese patients with type 2 diabetes mellitus (T2DM) who received tofogliflozin for 3 months. Their HbA1c, serum electrolytes (sodium, potassium, chloride), hematocrit, brain natriuretic peptide (cardiac volume load marker) and renin and aldosterone (RAA; an index of regulatory hormones involved in body fluid retention) were continuously monitored during the investigation period. Renal function and cardiac function (by echocardiography) were assessed throughout the period. HbA1c significantly decreased (β1=−0.341, p<0.0001, linear regression analysis [LRA]). Most of the hormonal, electrolyte, and physiological parameters were maintained throughout the study period. In these circumstances, E/e’ tended to decrease (β1=−0.382, p=0.13, LRA). Compared to the baseline, E/e’ was significantly decreased at 1 and 3 months (p<0.01, p<0.05). In the higher E/e’ group (E/e’≥10, n=34), E/e’ decreased significantly (β1=−0.63, p<0.05, LRA). ΔE/e’ was correlated with body-weight change during treatment (r=0.64, p<0.01). The 3-month tofogliflozin treatment improved glycemic control and diastolic function represented by E/e’ in T2DM patients, without affecting serum electrolytes, renal function, or RAA. No negative impacts on the patients were observed. Three-month tofogliflozin treatment lowered glucose and improved cardiac diastolic function

EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF); Scientific Opinion on Flavouring Group Evaluation 20, Revision 3 (FGE.20Rev3): Benzyl alcohols, benzaldehydes, a related acetal, benzoic acids, and related esters from chemical groups 23 and 30

&lt;p&gt;The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate five flavouring substances in the Flavouring Group Evaluation 304, using the Procedure in Commission Regulation (EC) No 1565/2000. None of the substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel concluded that the three substances [FL-no: 16.117, 16.123 and 16.125] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. For the remaining two candidate substances [FL-no: 16.118 and 16.124], no appropriate NOAEL was available and additional data are required. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all five candidate substances.&lt;/p&gt

EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF) ; Scientific Opinion on Flavouring Group Evaluation 06, Revision 4 (FGE.06Rev4 ): Straight - and branched - chain aliphatic unsaturated primary alcohols, aldehydes, carboxylic acids and esters from chemical groups 1, 3 and 4

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 56 flavouring substances in the Flavouring Group Evaluation 6, Revision 4, using the Procedure in Commission Regulation (EC) No 1565/2000. This revision is made due to the inclusion of six additional flavouring substances, (-)-3,7-dimethyl-6-octen-1-ol [FL-no: 02.229], dec-4(cis)-enal [FL-no: 05.137], neral [FL-no: 05.170], trans-3,7-dimethylocta-2,6-dienal (geranial) [FL-no: 05.188], trans-3-hexenyl formate [FL-no: 09.562] and cis-3-hexenyl 2-methylbutanoate [FL-no: 09.854]. None of the substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern and available data on metabolism and toxicity. The Panel concluded that the 56 substances [FL-no: 02.125, 02.138, 02.152, 02.170, 02.175, 02.176, 02.195, 02.201, 02.222, 02.229, 02.234, 05.061, 05.082, 05.137, 05.143, 05.170, 05.174, 05.188, 05.203, 05.217, 05.218, 05.220, 05.226, 08.074, 08.100, 08.102, 09.341, 09.368, 09.377, 09.562, 09.567, 09.569, 09.572, 09.575, 09.612, 09.638, 09.640, 09.643, 09.672, 09.673, 09.674, 09.831, 09.838, 09.854, 09.855, 09.871, 09.872, 09.884, 09.885, 09.897, 09.898, 09.928, 09.937, 09.938, 09.939 and 09.950] do not give rise to safety concern at their levels of dietary intake, estimated on the basis of the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Adequate specifications including complete purity criteria and identity for the materials of commerce have been provided for all 56 candidate substances

Modeling CICR in rat ventricular myocytes: voltage clamp studies

<p>Abstract</p> <p>Background</p> <p>The past thirty-five years have seen an intense search for the molecular mechanisms underlying calcium-induced calcium-release (CICR) in cardiac myocytes, with voltage clamp (VC) studies being the leading tool employed. Several VC protocols including lowering of extracellular calcium to affect <it>Ca</it>²⁺loading of the sarcoplasmic reticulum (SR), and administration of blockers caffeine and thapsigargin have been utilized to probe the phenomena surrounding SR <it>Ca</it>²⁺release. Here, we develop a deterministic mathematical model of a rat ventricular myocyte under VC conditions, to better understand mechanisms underlying the response of an isolated cell to calcium perturbation. Motivation for the study was to pinpoint key control variables influencing CICR and examine the role of CICR in the context of a physiological control system regulating cytosolic <it>Ca</it>²⁺concentration ([<it>Ca</it>²⁺]<it>_myo</it>).</p> <p>Methods</p> <p>The cell model consists of an electrical-equivalent model for the cell membrane and a fluid-compartment model describing the flux of ionic species between the extracellular and several intracellular compartments (cell cytosol, SR and the dyadic coupling unit (DCU), in which resides the mechanistic basis of CICR). The DCU is described as a controller-actuator mechanism, internally stabilized by negative feedback control of the unit's two diametrically-opposed <it>Ca</it>²⁺channels (trigger-channel and release-channel). It releases <it>Ca</it>²⁺flux into the cyto-plasm and is in turn enclosed within a negative feedback loop involving the SERCA pump, regulating[<it>Ca</it>²⁺]<it>_myo</it>.</p> <p>Results</p> <p>Our model reproduces measured VC data published by several laboratories, and generates graded <it>Ca</it>²⁺release at high <it>Ca</it>²⁺gain in a homeostatically-controlled environment where [<it>Ca</it>²⁺]<it>_myo</it>is precisely regulated. We elucidate the importance of the DCU elements in this process, particularly the role of the ryanodine receptor in controlling SR <it>Ca</it>²⁺release, its activation by trigger <it>Ca</it>²⁺, and its refractory characteristics mediated by the luminal SR <it>Ca</it>²⁺sensor. Proper functioning of the DCU, sodium-calcium exchangers and SERCA pump are important in achieving negative feedback control and hence <it>Ca</it>²⁺homeostasis.</p> <p>Conclusions</p> <p>We examine the role of the above <it>Ca</it>²⁺regulating mechanisms in handling various types of induced disturbances in <it>Ca</it>²⁺levels by quantifying cellular <it>Ca</it>²⁺balance. Our model provides biophysically-based explanations of phenomena associated with CICR generating useful and testable hypotheses.</p