scholarly journals Effect of citric-acid dialysate on the QTC-interval

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Karlien J. ter Meulen ◽  
Ben J. M. Hermans ◽  
Frank M. van der Sande ◽  
Bernard Canaud ◽  
Constantijn J. A. M. Konings ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Citric Acid ◽  
Qt Interval ◽  
Calcium Concentration ◽  
Qtc Interval ◽  
Ecg Monitoring ◽  
Blood Calcium ◽  
Cardiac Action ◽  
Significant Prolongation ◽  
Dialysate Calcium

AbstractLower dialysate calcium (dCa) concentration and dialysate citric-acidification may positively affect calcification propensity in serum of haemodialysis (HD) patients. However, the accompanying lower ionized blood calcium concentration may lead to a prolonged cardiac action potential, which is possibly pro-arrhythmic. The aim of this study is to investigate the influence of citric-acid dialysate on the QT-interval corrected for heart rate (QTc) compared to conventional dialysate with different dCa concentrations. We conducted a four-week multicentre, randomized cross-over trial. In week one and three patients received acetic-acid dialysate with a dCa of 1.50 mmol/l (A1.5), in week two and four acetic-acid dialysate with a dCa of 1.25 mmol/l (A1.25) or citric-acid dialysate (1.0 mmol/l) with a dCa of 1.50 mmol/l (C1.5) depending on randomization. Patients had continuous ECG monitoring during one session in week one, two and four. The data of 13 patients were available for analysis. Results showed a significant though limited increase of QTc with C1.5 (from 427 to 444 ms (start to end); p = 0.007) and with A1.25 (from 431 to 449 ms; p < 0.001), but not with A1.5 (from 439 to 443 ms; p = 0.13). In conclusion, we found that the use of C1.5 or A1.25 is associated with a significant prolongation of QTc which was however relatively limited.

scholarly journals QT Interval Prolongation in Patients with Systemic Sclerosis—Are the Holter ECG Recordings a Better Option for QT Interval Evaluation?

Medicina ◽  
2021 ◽  
Vol 57 (3) ◽  
pp. 295
Author(s):  
Elena E. Saramet ◽  
Doina-Clementina Cojocaru ◽  
Sorin Ungurianu ◽  
Robert D. Negru ◽  
Codrina Ancuta
Keyword(s):  
Systemic Sclerosis ◽  
Qt Interval ◽  
Qtc Interval ◽  
Ecg Monitoring ◽  
Interval Prolongation ◽  
Holter Ecg ◽  
Qt Interval Prolongation ◽  
Qtc Interval Prolongation ◽  
Interval Evaluation ◽  
Myocardial Involvement

Background and Objectives: Cardiac involvement in systemic sclerosis has important consequences on patient survival. Myocardial fibrosis and microcirculation involvement can generate arrhythmic complications, which can be associated with a higher death risk. QT interval prolongation is considered as a risk factor for ectopic ventricular events and can be evaluated using standard short ECG recordings or 24-h Holter ECG recordings. Materials and Methods: 39 patients with systemic sclerosis were submitted to a standard ECG recording at admission and 24-h Holter ECG monitoring. Results: QT interval values resulted from Holter ECG monitoring are higher than the values generated by the short-term ECG recordings. Holter ECG monitoring permits the detection of ventricular ectopy in patients with no events on standard ECG. Conclusions: In patients with systemic sclerosis, 24-h Holter ECG recordings can realize a more precise evaluation of the extent of QTc interval prolongation and ventricular ectopic events associated with myocardial involvement.

scholarly journals Experience with Hydroxychloroquine and Azithromycin in the COVID-19 Pandemic: Implications for QT Interval Monitoring

2020 ◽  
Author(s):  
Archana Ramireddy ◽  
Harpriya Chugh ◽  
Kyndaron Reinier ◽  
Joseph Ebinger ◽  
Eunice Park ◽  
...  
Keyword(s):  
Qt Interval ◽  
Case Series ◽  
Torsades De Pointes ◽  
Qtc Interval ◽  
Interval Prolongation ◽  
Qtc Prolongation ◽  
Qt Interval Prolongation ◽  
Significant Prolongation ◽  
Risk Indices ◽  
Increase Risk

ABSTRACTBackgroundDespite a paucity of clinical evidence, hydroxychloroquine and azithromycin are being administered widely to patients with verified or suspected COVID-19. Both drugs may increase risk of lethal arrhythmias associated with QT interval prolongation.MethodsWe performed a case series of COVID-19 positive/suspected patients admitted between 2/1/2020 and 4/4/2020 who were treated with azithromycin, hydroxychloroquine or a combination. We evaluated baseline and post-medication QT interval (QTc, Bazett’s) using 12-lead ECGs. Critical QTc prolongation was defined as: a) maximum QTc ≥500 ms (if QRS <120 ms) or QTc ≥550 (if QRS ≥120 ms) and b) increased QTc of ≥60 ms. Tisdale score and Elixhauser comorbidity index were calculated.ResultsOf 490 COVID-19 positive/suspected patients, 314 (64%) received either/both drugs, and 98 (73 COVID-19 positive, 25 suspected) met study criteria (age 62±17 yrs, 61% male). Azithromycin was prescribed in 28%, hydroxychloroquine in 10%, and both in 62%. Baseline mean QTc was 448±29 ms and increased to 459±36ms (p=0.005) with medications. Significant prolongation was observed only in men (18±43 ms vs -0.2±28 ms in women, p=0.02). 12% of patients reached critical QTc prolongation. In a multivariable logistic regression, age, sex, Tisdale score, Elixhauser score, and baseline QTc were not associated with critical QTc prolongation (p>0.14). Changes in QTc were highest with the combination compared to either drug, with many-fold greater prolongation with the combination vs. azithromycin alone (17±39 vs. 0.5±40 ms, p=0.07). No patients manifested torsades de pointes.ConclusionsOverall, 12% of patients manifested critical QTc interval prolongation, and traditional risk indices failed to flag these patients. With the drug combination, QTc prolongation was several-fold higher compared to azithromycin alone. The balance between uncertain benefit and potential risk when treating COVID-19 patients with these drugs should be carefully assessed prior to use.

Changes of QT interval in the acute phase after pulmonary vein isolation for paroxysmal atrial fibrillation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Chikata ◽  
T Kato ◽  
K Ududa ◽  
S Fujita ◽  
K Otowa ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulmonary Vein ◽  
Female Patient ◽  
Pulmonary Vein Isolation ◽  
Acute Phase ◽  
Paroxysmal Atrial Fibrillation ◽  
Qt Interval ◽  
Qt Prolongation ◽  
Qtc Interval ◽  
The Impact

Abstract Introduction Pulmonary vein isolation (PVI) affects ganglionated plexi (GP) around the atrium, leading to a modification of the intrinsic cardiac autonomic system (ANS). In animal models, GP ablation has a potential risk of QT prolongation and ventricular arrhythmias. However, the impact of PVI on QT intervals in humans remains unclear. Purpose This study aims to evaluate the Impact of PVI on QT interval in patients with paroxysmal atrial fibrillation. Methods We analyzed consecutive 117 PAF patients for their first PVI procedures. 12-lead ECG was evaluated at baseline, 4 hr, day 1, 1 month, and 3 months after ablation. Only patients with sinus rhythm on 12-lead ECG at each evaluation point without antiarrhythmic drugs were included. Results Heart rate significantly increased at 4 hr, day 1, and 1 month. Raw QT interval prolonged at 4 hr (417.1±41.6 ms, P&lt;0.001) but shortened at day 1 (376.4±34.1 ms, P&lt;0.001), 1 month (382.2±31.5 ms, P&lt;0.001), and 3 months (385.1±32.8 ms, P&lt;0.001) compared to baseline (391.6±31.4 ms). Bazett- and Fridericia- corrected QTc intervals significantly prolonged at 4hr (Bazett: 430.8±27.9 ms, P&lt;0.001; Fridericia: 425.8±27.4 ms, P&lt;0.001), day1 (Bazett: 434.8±22.3 ms, P&lt;0.001; Fridericia: 414.1±23.7 ms, P&lt;0.001), 1M (Bazett: 434.8±22.3 ms, P&lt;0.001; Fridericia: 408.2±21.0 ms, P&lt;0.05), and 3M (Bazett: 420.1±21.8 ms, P&lt;0.001; Fridericia: 407.8±21.1 ms, P&lt;0.05) compared to baseline (Bazett: 404.9±25.2 ms; Fridericia: 400.0±22.6 ms). On the other hand, Framingham- and Hodges- corrected QTc interval significantly prolonged only at 4hr (Framingham: 424.1±26.6 ms, P&lt;0.001; Hodges: 426.8±28.4 ms, P&lt;0.001) and at day1 (Framingham: 412.3±29.3 ms, P&lt;0.01; Hodges: 410.6±40.2 ms, P&lt;0.05) compared to baseline (Framingham: 399.2±22.7 ms; Hodges: 400.7±22.8 ms). At 4 hr after ablation, raw QT and QTc of all formulas significantly prolonged than baseline. Raw QT and QTc prolongation at 4hr after ablation were more frequently observed in female patients. Multiple regression analysis revealed that female patient is a significant predictor of raw QT and QTc interval prolongation of all formulas 4hr after PVI. Conclusions Raw QT and QTc prolonged after PVI, especially in the acute phase. Female patient is a risk factor for QT prolongation in the acute phase after PVI. Funding Acknowledgement Type of funding source: None

scholarly journals Antipsychotics in routine treatment are minor contributors to QT prolongation compared to genetics and age

2021 ◽  
pp. 026988112110034
Author(s):  
Leif Hommers ◽  
Maike Scherf-Clavel ◽  
Roberta Stempel ◽  
Julian Roth ◽  
Matthias Falter ◽  
...  
Keyword(s):  
Qt Interval ◽  
Multivariate Regression Analysis ◽  
Cardiac Repolarization ◽  
Qtc Interval ◽  
Serum Concentrations ◽  
Drug Induced ◽  
Individual Level ◽  
Main Determinants ◽  
The Individual ◽  
Polygenic Variation

Background: Drug-induced prolongation of cardiac repolarization limits the treatment with many psychotropic drugs. Recently, the contribution of polygenic variation to the individual duration of the QT interval was identified. Aims: To explore the interaction between antipsychotic drugs and the individual polygenic influence on the QT interval. Methods: Retrospective analysis of clinical and genotype data of 804 psychiatric inpatients diagnosed with a psychotic disorder. The individual polygenic influence on the QT interval was calculated according to the method of Arking et al. Results: Linear regression modelling showed a significant association of the individual polygenic QT interval score (ßstd = 0.176, p < 0.001) and age (ßstd = 0.139, p < 0.001) with the QTc interval corrected according to Fridericia’s formula. Sex showed a nominal trend towards significance (ßstd = 0.064, p = 0.064). No association was observed for the number of QT prolonging drugs according to AZCERT taken. Subsample analysis ( n = 588) showed a significant association of potassium serum concentrations with the QTc interval (ßstd = −0.104, p = 0.010). Haloperidol serum concentrations were associated with the QTc interval only in single medication analysis ( n = 26, ßstd = 0.101, p = 0.004), but not in multivariate regression analysis. No association was observed for aripiprazole, clozapine, quetiapine and perazine, while olanzapine and the sum of risperidone and its metabolite showed a negative association. Conclusions: Individual genetic factors and age are main determinants of the QT interval. Antipsychotic drug serum concentrations within the therapeutic range contribute to QTc prolongation on an individual level.

scholarly journals Prevalence and Risk Factors of Prolonged QTc Interval among Chinese Patients with Type 2 Diabetes

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Xiang Li ◽  
Hui Ren ◽  
Zhang-rong Xu ◽  
Yan-jun Liu ◽  
Xiao-pin Yang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Blood Pressure ◽  
Type 2 Diabetes ◽  
Waist Circumference ◽  
Qt Interval ◽  
Postprandial Glucose ◽  
Chinese Patients ◽  
Qtc Interval ◽  
Fasting Insulin

Objectives. The aim of this study was to evaluate the prevalence and the risk factors of prolonged QTc interval among Chinese patients with type 2 diabetes.Methods. The retrospective study included 3156 outpatients from the Diabetes Centre, the 306th Hospital of PLA, during the period from September 2003 to June 2010. QT interval was measured manually in the 12-lead conventional electrocardiogram. The QT interval corrected for heart rate (QTc) was calculated using Bazett’s formula. Additional demographic and laboratory data were also collected. Potential risk factors of prolonged QTc interval were assessed using multivariable regression.Results.The prevalence of prolonged QTc interval among Chinese patients with type 2 diabetes was 30.1%. Height (OR 0.156, 95% CI 0.032~0.748), waist circumference (OR 1.025, 95% CI 1.010~1.040), diastolic blood pressure (OR 1.016, 95% CI 1.007~1.026), postprandial glucose (OR 1.040, 95% CI 1.022~1.059), fasting insulin (OR 1.014, 95% CI 1.003~1.025), and presence of microalbuminuria (OR 1.266, 95% CI 1.033~1.551) were significant risk factors.Conclusions. The prevalence of prolonged QTc interval among Chinese patients with type 2 diabetes is high. Risk factors for prolongation of QTc interval were low height, high waist circumference, increasing diastolic blood pressure levels, high postprandial glucose levels, high fasting insulin levels, and presence of microalbuminuria.

Effect of pH, Acidulant, Time, and Temperature on the Growth and Survival of Listeria monocytogenes

1989 ◽  
Vol 52 (8) ◽  
pp. 571-573 ◽  
Author(s):  
KENT M. SORRELLS ◽  
DAVIN C. ENIGL ◽  
JOHN R. HATFIELD
Keyword(s):  
Antimicrobial Activity ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Hydrochloric Acid ◽  
Malic Acid ◽  
Incubation Temperature ◽  
Growth And Survival ◽  
Ph Values

The effect of different acids, pH, incubation time, and incubation temperature on the growth and survival of four strains of Listeria monocytogenes in tryptic soy broth was compared. Hydrochloric acid (HCl), acetic acid (AA), lactic acid (LA), malic acid (MA), and citric acid (CA) were used to acidify tryptic soy broth to pH values 4.4, 4.6, 4.8, 5.0, and 5.2 pH. Incubation times were 1, 3, 7, 14, and 28 d at 10, 25, and 35°C. The inhibition of L. monocytogenes in the presence of high acidity appears to be a function of acid and incubation temperature. Based on equal pH values, the antimicrobial activity is AA &gt; LA &gt; CA ≥ MA &gt; HCl at all incubation times and temperatures. When based on equal molar concentration, the activity appeared to be CA ≥ MA &gt; LA ≥ AA &gt; HCl at 35 and 25°C, and MA &gt; CA &gt; AA ≥ LA &gt; HCl at 10°C. Greatest antimicrobial activity occurred at 35°C. Greatest survival occurred at 10°C and greatest growth occurred at 25°C. Final pH of the medium was as low as 3.8 in HCl at 28 d. All strains grew well at pH values lower than the minimum previously reported (5.5–5.6).

scholarly journals Microbiological and Physicochemical Characterization of Small-Scale Cocoa Fermentations and Screening of Yeast and Bacterial Strains To Develop a Defined Starter Culture

2012 ◽  
Vol 78 (15) ◽  
pp. 5395-5405 ◽  
Author(s):  
Gilberto Vinícius de Melo Pereira ◽  
Maria Gabriela da Cruz Pedrozo Miguel ◽  
Cíntia Lacerda Ramos ◽  
Rosane Freitas Schwan
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Citric Acid ◽  
Dominant Species ◽  
Starter Culture ◽  
Physicochemical Characterization ◽  
Cocoa Bean ◽  
Small Scale ◽  
Content Type ◽  
Cocoa Bean Fermentation

ABSTRACTSpontaneous cocoa bean fermentations performed under bench- and pilot-scale conditions were studied using an integrated microbiological approach with culture-dependent and culture-independent techniques, as well as analyses of target metabolites from both cocoa pulp and cotyledons. Both fermentation ecosystems reached equilibrium through a two-phase process, starting with the simultaneous growth of the yeasts (withSaccharomyces cerevisiaeas the dominant species) and lactic acid bacteria (LAB) (Lactobacillus fermentumandLactobacillus plantarumwere the dominant species), which were gradually replaced by the acetic acid bacteria (AAB) (Acetobacter tropicaliswas the dominant species). In both processes, a sequence of substrate consumption (sucrose, glucose, fructose, and citric acid) and metabolite production kinetics (ethanol, lactic acid, and acetic acid) similar to that of previous, larger-scale fermentation experiments was observed. The technological potential of yeast, LAB, and AAB isolates was evaluated using a polyphasic study that included the measurement of stress-tolerant growth and fermentation kinetic parameters in cocoa pulp media. Overall, strainsL. fermentumUFLA CHBE8.12 (citric acid fermenting, lactic acid producing, and tolerant to heat, acid, lactic acid, and ethanol),S. cerevisiaeUFLA CHYC7.04 (ethanol producing and tolerant to acid, heat, and ethanol), andAcetobacter tropicalisUFLA CHBE16.01 (ethanol and lactic acid oxidizing, acetic acid producing, and tolerant to acid, heat, acetic acid, and ethanol) were selected to form a cocktail starter culture that should lead to better-controlled and more-reliable cocoa bean fermentation processes.

Individualizing the dialysate calcium concentration

2015 ◽  
Vol 24 (6) ◽  
pp. 538-545 ◽  
Author(s):  
Guillaume Jean ◽  
Charles Chazot
Keyword(s):  
Calcium Concentration ◽  
Dialysate Calcium

Efficacy Comparison of Some New Natural-Product Herbicides for Weed Control at Two Growth Stages

2009 ◽  
Vol 23 (3) ◽  
pp. 431-437 ◽  
Author(s):  
Hussein F. H. Abouziena ◽  
Ahmad A. M. Omar ◽  
Shiv D. Sharma ◽  
Megh Singh
Keyword(s):  
Acetic Acid ◽  
Citric Acid ◽  
Natural Product ◽  
Weed Control ◽  
Growth Stages ◽  
Clove Oil ◽  
Yellow Nutsedge ◽  
Natural Herbicides ◽  
Redroot Pigweed ◽  
Wild Mustard

There is an urgent need to accelerate the development and implementation of effective organic-compliant herbicides that are environmentally safe and that help the producer meet increasing consumer demand for organic products. Therefore, greenhouse experiments were conducted to evaluate the effectiveness of acetic acid (5%), acetic acid (30%), citric acid (10%), citric acid (5%) + garlic (0.2%), citric acid (10%) + garlic (0.2%), clove oil (45.6%), and corn gluten meal (CGM) compounds as natural-product herbicides for weed control. The herbicides were applied to the broadleaf weeds stranglervine, wild mustard, black nightshade, sicklepod, velvetleaf, and redroot pigweed and to narrowleaf weeds crowfootgrass, Johnsongrass, annual ryegrass, goosegrass, green foxtail, and yellow nutsedge. The herbicides were applied POST at two weed growth stages, namely, two to four and four to six true-leaf stages. CGM was applied PPI in two soil types. Citric acid (5%) + garlic (0.2%) had the greatest control (98%) of younger broadleaf weeds, followed by acetic acid (30%) > CGM > citric acid (10%) > acetic acid (5%) > citric acid (10%) + garlic (0.2%), and clove oil. Wild mustard was most sensitive to these herbicides, whereas redroot pigweed was the least sensitive. Herbicides did not control narrowleaf weeds except for acetic acid (30%) when applied early POST (EPOST) and CGM. Acetic acid (30%) was phytotoxic to all broadleaf weeds and most narrowleaf weeds when applied EPOST. Delayed application until the four- to six-leaf stage significantly reduced efficacy; acetic acid was less sensitive to growth stage than other herbicides. These results will help to determine effective natural herbicides for controlling weeds in organic farming.

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