Atrial fibrillation(AF)is the most common arrhythmia in clinical setting and has been increasingly prevalent due to the aging population.AF is associated with a three to fivefold increased risk of stroke.Treatment opt...Atrial fibrillation(AF)is the most common arrhythmia in clinical setting and has been increasingly prevalent due to the aging population.AF is associated with a three to fivefold increased risk of stroke.Treatment options include pharmacological and electrical cardioversion,each carrying specific risks.AF may resolve spontaneously,but often recurs,making a“watch-andwait”strategy a reasonable approach to avoid unnecessary antiarrhythmic therapy.展开更多
The widespread popularization and application of laser technology have provided a powerful tool for a deeper understanding of the material world and given birth to several emerging research fields.This study mainly fo...The widespread popularization and application of laser technology have provided a powerful tool for a deeper understanding of the material world and given birth to several emerging research fields.This study mainly focuses on the following three key aspects.First,the classical ensemble method is adopted to conduct a comprehensive and in-depth analysis of two-dimensional(2D)matter–wave pulses in Bose–Fermi mixed gases(including linear and nonlinear pulses).Second,under the strict constraints of unitary systems,a coupled Kd V equation is successfully derived,and the prolongation structure theory is skillfully used to carry out detailed calculations and analyses on this equation.Thus,the prolongation algebra of this equation is accurately determined,and the corresponding Lax pair is rigorously derived.Finally,based on the carefully obtained Lax pair from the prolongation structure theory,the soliton solutions of this equation are further analyzed in depth,and intuitive images of each soliton solution are carefully drawn.This lays a solid foundation for subsequent detailed research on these soliton characteristics and provides great convenience.展开更多
AIM To determine the prevalence of QT prolongation in a large series of end stage liver disease(ESLD)patients and its association to clinical variables and mortality.METHODS The QT interval was measured and corrected ...AIM To determine the prevalence of QT prolongation in a large series of end stage liver disease(ESLD)patients and its association to clinical variables and mortality.METHODS The QT interval was measured and corrected for heart rate for each patient,with a prolonged QT cutoff defined as QT>450 ms for males and QT>470 ms for females.Multiple clinical variables were evaluated including sex,age,serum sodium,international normalized ratio,creatinine,total bilirubin,beta-blocker use,Model for EndStage Liver Disease(MELD),MELD-Na,and etiology of liver disease.RESULTS Among 406 ESLD patients analyzed,207(51.0%)had QT prolongation.The only clinical variable associated with QT prolongation was male gender(OR=3.04,95%CI:2.01-4.60,P<0.001).During the study period,187patients(46.1%)died.QT prolongation was a significant independent predictor of mortality(OR=1.69,95%CI:1.03-2.77,P=0.039).In addition,mortality was also associated with viral etiology of ESLD,elevated MELD score and its components(P<0.05 for all).No significant reversibility in the QT interval was seen after liver transplantation.CONCLUSION QT prolongation was commonly encountered in an ESLD population,especially in males,and served as a strong independent marker for increased mortality in ESLD patients.展开更多
Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSding...Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.展开更多
Based upon the covariant prolongation structures theory, we construct the sl（2, R）×R（p） prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtai...Based upon the covariant prolongation structures theory, we construct the sl（2, R）×R（p） prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtain the inverse scattering equations given by Konno et al. and the corresponding Riccati equation. The Baecklund transformations are also presented.展开更多
In this paper, a new nonlinear integrable coupling system of the soliton hierarchy is presented. Prom the Lax pairs, the coupled KdV equations are constructed successfully. Based on the prolongation method of Wahlquis...In this paper, a new nonlinear integrable coupling system of the soliton hierarchy is presented. Prom the Lax pairs, the coupled KdV equations are constructed successfully. Based on the prolongation method of Wahlquist and Estabrook, we study the prolongation structure of the nonlinear integrable couplings of the KdV equation.展开更多
We investigate the coupled inhomogeneous nonlinear Schrodinger equation by the covariant prolongationstructure theory, and obtain its Lax's representation. Moreover, we present the corresponding Riccati equations,...We investigate the coupled inhomogeneous nonlinear Schrodinger equation by the covariant prolongationstructure theory, and obtain its Lax's representation. Moreover, we present the corresponding Riccati equations, Backlundtransformation, and one-soliton solution.展开更多
The prolongation structure methodologies of Wahlquist-Estabrook [Wahlquist H D and Estabrook F B 1975 J. Math. Phys. 16 1] for nonlinear differential equations are applied to a variable-coefficient KdV equation. Based...The prolongation structure methodologies of Wahlquist-Estabrook [Wahlquist H D and Estabrook F B 1975 J. Math. Phys. 16 1] for nonlinear differential equations are applied to a variable-coefficient KdV equation. Based on the obtained prolongation structure, a Lie algebra with five parameters is constructed. Under certain conditions, a Lie algebra representation and three kinds of Lax pairs for the variable coefficient KdV equation are derived.展开更多
The Wahlquist-Estabrook （WE） prolongation structures of modified Boussi-nesq （MB） system are studied from the coverings point of view. The realizations and classifications of one-dimensional coverings of this syst...The Wahlquist-Estabrook （WE） prolongation structures of modified Boussi-nesq （MB） system are studied from the coverings point of view. The realizations and classifications of one-dimensional coverings of this system are obtained completely. More-over the sufficient and necessary conditions for a vector field to be a nonlocal symmetry of this system are also demonstrated in the WE prolongation structures.展开更多
The integrability of a （2＋1）-dimensional super nonlinear evolution equation is analyzed in the framework of the fermionie covariant prolongation structure theory. We construct the prolongation structure of the mult...The integrability of a （2＋1）-dimensional super nonlinear evolution equation is analyzed in the framework of the fermionie covariant prolongation structure theory. We construct the prolongation structure of the multidimen- sional super integrable equation and investigate its Lax representation. Furthermore, the Backlund transformation is presented and we derive a solution to the super integrable equation.展开更多
Drug-induced QT prolongation is a serious clinical issue in developing novel drug candidates and marketing drugs. A major cause of QT prolongation is direct inhibition of human ether-à-go-go-related gene (hERG) c...Drug-induced QT prolongation is a serious clinical issue in developing novel drug candidates and marketing drugs. A major cause of QT prolongation is direct inhibition of human ether-à-go-go-related gene (hERG) channels. Reduction in repolarization-related channel expression levels on plasma membranes is another mechanism that induces QT prolongation. Recently, we established a system for assessing the risk of QT prolongation by using human embryonic stem cell-derived cardiomyocyte clusters (hES-CMCs) in which the field potential duration (FPD) or corrected FPD (FPDc) was measured as an indicator of drug-induced QT interval prolongation. Here, we examined whether this system was able to detect FPDc prolongation caused by pentamidine or probucol, both of which can induce QT prolongation after long-term treatment. hES-CMCs were treated with pentamidine or probucol, and the FPDc of the same clusters was measured 10 min, 4 h, and 24 h after the start of treatment. Concentration-dependent FPDc prolongation was observed at 24 h, but not at 10 min, with pentamidine or probucol treatment. These results suggest that the hES-CMC-based assessment system can be used to detect both acute (at 10 min) and delayed (at 24 h) QT prolongation risk on the same platform by simple alteration of the extended culture period.展开更多
In this paper, we investigate the Gross-Pitaevskii (GP) equation which describes the propagation of an electron plasma wave packet with a large wavelength and small amplitude in a medium with a parabolic density and c...In this paper, we investigate the Gross-Pitaevskii (GP) equation which describes the propagation of an electron plasma wave packet with a large wavelength and small amplitude in a medium with a parabolic density and constant interactional damping by the Covariant Prolongation Structure Theory. As a result, we obtain general forms of Lax-Pair representations. In addition, some hidden structural symmetries that govern the dynamics of the GP equation such as SL(2,R), SL(2,C), Virasoro algebra, SU(1,1) and SU(2) are unearthed. Using the Riccati form of the linear eigenvalue problem, infinite number of conservation laws of the GP equation is explicitly constructed and the exact analytical soliton solutions are obtained by employing the simple and straightforward Hirota’s bilinear method.展开更多
Objective: To identify the effects of antipsychotics on QTc prolongation in light of age, gender, antipsychotic combination pattern, antipsychotic doses and cytochrome P450 (CYP) mediation, using large database descri...Objective: To identify the effects of antipsychotics on QTc prolongation in light of age, gender, antipsychotic combination pattern, antipsychotic doses and cytochrome P450 (CYP) mediation, using large database describing the antipsychotic treatment of patients with schizophrenia in Japan. Methods: Using database of 4176 patients with schizophrenia discharged between April 2004 and March 2005 and receiving outpatient treatment from 526 psychiatric hospitals in Japan. Of the patients, 1437 were included for the analysis. These patients were classified into three groups according to the antipsychotic CPZ-equivalent doses that they received (low, 1 - 299 mg;middle, 300 - 999 mg;and high, ≥1000 mg). QTc intervals ≥ 440 msec were considered prolonged. We reviewed all the package inserts of the antipsychotics used from the website of Pharmaceuticals and Medical Devices Agency. Results: The mean QTc interval of the total patient group was 410.4 ± 23.3 msec. The females had significantly higher QTc values than the males (414.5 ± 24.0 vs. 406.8 ± 22.2 msec, respectively;p 0.05). Logistic regression analysis revealed that female gender (odds ratio [OR] = 1.83;95% CI: 1.28 - 2.56), CYP3A4-metabolized drugs (OR 1.56;95% CI: 1.05 - 2.30) were associated with an increased risk of QTc prolongation. Conclusion: The co-prescription of CYP3A4-mediated antipsychotic drugs should be carefully considered in females due to potential risk of QTc prolongation. Further studies of the cardiovascular safety of antipsychotics are warranted in patients receiving multiple medications.展开更多
Equations of the reaction-diffusion type are very well known and have been extensively studied in many research areas. In this paper, the prolongation structures for the system of the reaction-diffusion type are inves...Equations of the reaction-diffusion type are very well known and have been extensively studied in many research areas. In this paper, the prolongation structures for the system of the reaction-diffusion type are investigated from theory of coverings. The realizations and the classifications of the one-dimensional coverings of the system are researched. And the corresponding conservation law of the one-dimensional Abelian coverings is concluded, which is closely connected with the symmetry of the system by Noether theorem.展开更多
The United Nations Convention on the Law of the Sea entitled the coastal States to naturally extend the continental shelf, which has caused more drastic disputes of maritime delimitation. This paper devotes to clarify...The United Nations Convention on the Law of the Sea entitled the coastal States to naturally extend the continental shelf, which has caused more drastic disputes of maritime delimitation. This paper devotes to clarifying the significant concept of natural prolongation through an effect method combing the legal principles and technical analysis. Firstly, the classic samples with respect of the development of geological features are traced. Based on these samples, the classification with a model is proposed in order to affirm the concept＇s significance under certain geomorphologic situations. Lastly, scientific analysis is used to present two potential prolongation situations and emphasize that all the technical analysis on maritime delimitation should be complied with international law and protect the common interest of all the mankind.展开更多
BACKGROUND QTc interval prolongation with an increased risk of torsade de pointes(Tsd)has been described in coronavirus disease 2019(COVID-19)patients treated with hydroxychloroquine(HCQ)and azithromycin(AZI)in Wester...BACKGROUND QTc interval prolongation with an increased risk of torsade de pointes(Tsd)has been described in coronavirus disease 2019(COVID-19)patients treated with hydroxychloroquine(HCQ)and azithromycin(AZI)in Western countries.In the DR Congo,few studies have evaluated the safety of this association or proposed new molecules.AIM To determine the incidence of QTc prolongation and Tsd in COVID-19 patients treated with HCQ-AZIs vs doubase C(new molecule).METHODS In present randomized clinical trial,we have included patients with mild or moderate COVID-19 treated with either HCQ-AZI or doubase C.Electrocardiogram(ECG)changes on day 14 of randomization were determined based on pretreatment tracing.Prolonged QTc was defined as≥500 ms on day 14 or an increase of≥80 ms compared to pretreatment tracing.Patients with cardiac disease,those undergoing other treatments likely to prolong QTc,and those with disturbed ECG tracings were excluded from the study.RESULTS The study included 258 patients(mean age 41±15 years;52%men;3.4%diabetics,11.1%hypertensive).Mild and moderate COVID-19 were found in 93.5%and 6.5%of patients,respectively.At baseline,all patients had normal sinus rhythm,a mean heart rate 78±13/min,mean PR space 170±28 ms,mean QRS 76±13 ms,and mean QTc 405±30 ms.No complaints suggesting cardiac involvement were reported during or after treatment.Only four patients(1.5%)experienced QTc interval prolongation beyond 500 ms.Similarly,only five patients(1.9%)had an increase in the QTc interval of more than 80 ms.QTc prolongation was more significant in younger patients,those with high viral load at baseline,and those receiving HCQ-AZI(P<0.05).None of the patients developed Tsd.CONCLUSION QTc prolongation without Tsd was observed at a lower frequency in patients treated with HCQ-AZI vs doubase C.The absence of comorbidities and concurrent use of other products that are likely to cause arrhythmia may explain our results.展开更多
文摘Atrial fibrillation(AF)is the most common arrhythmia in clinical setting and has been increasingly prevalent due to the aging population.AF is associated with a three to fivefold increased risk of stroke.Treatment options include pharmacological and electrical cardioversion,each carrying specific risks.AF may resolve spontaneously,but often recurs,making a“watch-andwait”strategy a reasonable approach to avoid unnecessary antiarrhythmic therapy.
基金Project supported by the National Natural Science Foundation of China(Grant No.12261072)。
文摘The widespread popularization and application of laser technology have provided a powerful tool for a deeper understanding of the material world and given birth to several emerging research fields.This study mainly focuses on the following three key aspects.First,the classical ensemble method is adopted to conduct a comprehensive and in-depth analysis of two-dimensional(2D)matter–wave pulses in Bose–Fermi mixed gases(including linear and nonlinear pulses).Second,under the strict constraints of unitary systems,a coupled Kd V equation is successfully derived,and the prolongation structure theory is skillfully used to carry out detailed calculations and analyses on this equation.Thus,the prolongation algebra of this equation is accurately determined,and the corresponding Lax pair is rigorously derived.Finally,based on the carefully obtained Lax pair from the prolongation structure theory,the soliton solutions of this equation are further analyzed in depth,and intuitive images of each soliton solution are carefully drawn.This lays a solid foundation for subsequent detailed research on these soliton characteristics and provides great convenience.
文摘AIM To determine the prevalence of QT prolongation in a large series of end stage liver disease(ESLD)patients and its association to clinical variables and mortality.METHODS The QT interval was measured and corrected for heart rate for each patient,with a prolonged QT cutoff defined as QT>450 ms for males and QT>470 ms for females.Multiple clinical variables were evaluated including sex,age,serum sodium,international normalized ratio,creatinine,total bilirubin,beta-blocker use,Model for EndStage Liver Disease(MELD),MELD-Na,and etiology of liver disease.RESULTS Among 406 ESLD patients analyzed,207(51.0%)had QT prolongation.The only clinical variable associated with QT prolongation was male gender(OR=3.04,95%CI:2.01-4.60,P<0.001).During the study period,187patients(46.1%)died.QT prolongation was a significant independent predictor of mortality(OR=1.69,95%CI:1.03-2.77,P=0.039).In addition,mortality was also associated with viral etiology of ESLD,elevated MELD score and its components(P<0.05 for all).No significant reversibility in the QT interval was seen after liver transplantation.CONCLUSION QT prolongation was commonly encountered in an ESLD population,especially in males,and served as a strong independent marker for increased mortality in ESLD patients.
基金The project supported by Tianyuan Foundation for Mathematics under Grant No. 10626016 of National Natural Science Foundation of China, China Postdoctoral Science Foundation, Beijing Jiao-Wei Key Project under Grant No. KZ 200310028010, and National Natural Science Foundation of China under Grant No. 10375038
文摘Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.
文摘Based upon the covariant prolongation structures theory, we construct the sl（2, R）×R（p） prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtain the inverse scattering equations given by Konno et al. and the corresponding Riccati equation. The Baecklund transformations are also presented.
基金Project supported by the Scientific Research Fundation of the Education Department of Liaoning Province,China(GrantNo.L2010513)the China Postdoctoral Science Foundation(Grant No.2011M500404)
文摘In this paper, a new nonlinear integrable coupling system of the soliton hierarchy is presented. Prom the Lax pairs, the coupled KdV equations are constructed successfully. Based on the prolongation method of Wahlquist and Estabrook, we study the prolongation structure of the nonlinear integrable couplings of the KdV equation.
基金Supported by Beijing Jiao-Wei Key Project KZ200810028013the Natural Science Foundation of China under Grant No. 10871135
文摘We investigate the coupled inhomogeneous nonlinear Schrodinger equation by the covariant prolongationstructure theory, and obtain its Lax's representation. Moreover, we present the corresponding Riccati equations, Backlundtransformation, and one-soliton solution.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10735030and90718041)the Shanghai Leading Academic Discipline Project,China(Grant No.B412)+1 种基金the Program for Changjiang Scholars,the Innovative Research Team in University,Ministry of Education of China(Grant No.IRT0734)the K.C.Wong Magna Fund in Ningbo University,China
文摘The prolongation structure methodologies of Wahlquist-Estabrook [Wahlquist H D and Estabrook F B 1975 J. Math. Phys. 16 1] for nonlinear differential equations are applied to a variable-coefficient KdV equation. Based on the obtained prolongation structure, a Lie algebra with five parameters is constructed. Under certain conditions, a Lie algebra representation and three kinds of Lax pairs for the variable coefficient KdV equation are derived.
文摘The Wahlquist-Estabrook （WE） prolongation structures of modified Boussi-nesq （MB） system are studied from the coverings point of view. The realizations and classifications of one-dimensional coverings of this system are obtained completely. More-over the sufficient and necessary conditions for a vector field to be a nonlocal symmetry of this system are also demonstrated in the WE prolongation structures.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11605096,11547101 and 11601247
文摘The integrability of a （2＋1）-dimensional super nonlinear evolution equation is analyzed in the framework of the fermionie covariant prolongation structure theory. We construct the prolongation structure of the multidimen- sional super integrable equation and investigate its Lax representation. Furthermore, the Backlund transformation is presented and we derive a solution to the super integrable equation.
文摘Drug-induced QT prolongation is a serious clinical issue in developing novel drug candidates and marketing drugs. A major cause of QT prolongation is direct inhibition of human ether-à-go-go-related gene (hERG) channels. Reduction in repolarization-related channel expression levels on plasma membranes is another mechanism that induces QT prolongation. Recently, we established a system for assessing the risk of QT prolongation by using human embryonic stem cell-derived cardiomyocyte clusters (hES-CMCs) in which the field potential duration (FPD) or corrected FPD (FPDc) was measured as an indicator of drug-induced QT interval prolongation. Here, we examined whether this system was able to detect FPDc prolongation caused by pentamidine or probucol, both of which can induce QT prolongation after long-term treatment. hES-CMCs were treated with pentamidine or probucol, and the FPDc of the same clusters was measured 10 min, 4 h, and 24 h after the start of treatment. Concentration-dependent FPDc prolongation was observed at 24 h, but not at 10 min, with pentamidine or probucol treatment. These results suggest that the hES-CMC-based assessment system can be used to detect both acute (at 10 min) and delayed (at 24 h) QT prolongation risk on the same platform by simple alteration of the extended culture period.
文摘In this paper, we investigate the Gross-Pitaevskii (GP) equation which describes the propagation of an electron plasma wave packet with a large wavelength and small amplitude in a medium with a parabolic density and constant interactional damping by the Covariant Prolongation Structure Theory. As a result, we obtain general forms of Lax-Pair representations. In addition, some hidden structural symmetries that govern the dynamics of the GP equation such as SL(2,R), SL(2,C), Virasoro algebra, SU(1,1) and SU(2) are unearthed. Using the Riccati form of the linear eigenvalue problem, infinite number of conservation laws of the GP equation is explicitly constructed and the exact analytical soliton solutions are obtained by employing the simple and straightforward Hirota’s bilinear method.
文摘Objective: To identify the effects of antipsychotics on QTc prolongation in light of age, gender, antipsychotic combination pattern, antipsychotic doses and cytochrome P450 (CYP) mediation, using large database describing the antipsychotic treatment of patients with schizophrenia in Japan. Methods: Using database of 4176 patients with schizophrenia discharged between April 2004 and March 2005 and receiving outpatient treatment from 526 psychiatric hospitals in Japan. Of the patients, 1437 were included for the analysis. These patients were classified into three groups according to the antipsychotic CPZ-equivalent doses that they received (low, 1 - 299 mg;middle, 300 - 999 mg;and high, ≥1000 mg). QTc intervals ≥ 440 msec were considered prolonged. We reviewed all the package inserts of the antipsychotics used from the website of Pharmaceuticals and Medical Devices Agency. Results: The mean QTc interval of the total patient group was 410.4 ± 23.3 msec. The females had significantly higher QTc values than the males (414.5 ± 24.0 vs. 406.8 ± 22.2 msec, respectively;p 0.05). Logistic regression analysis revealed that female gender (odds ratio [OR] = 1.83;95% CI: 1.28 - 2.56), CYP3A4-metabolized drugs (OR 1.56;95% CI: 1.05 - 2.30) were associated with an increased risk of QTc prolongation. Conclusion: The co-prescription of CYP3A4-mediated antipsychotic drugs should be carefully considered in females due to potential risk of QTc prolongation. Further studies of the cardiovascular safety of antipsychotics are warranted in patients receiving multiple medications.
文摘Equations of the reaction-diffusion type are very well known and have been extensively studied in many research areas. In this paper, the prolongation structures for the system of the reaction-diffusion type are investigated from theory of coverings. The realizations and the classifications of the one-dimensional coverings of the system are researched. And the corresponding conservation law of the one-dimensional Abelian coverings is concluded, which is closely connected with the symmetry of the system by Noether theorem.
基金The National Social Science Foundation of China under contract No.16CFX069China Postdoctoral Science Foundations under contract Nos 2015M581913 and 2016T90531the Fundamental Research Funds for the Central Universities
文摘The United Nations Convention on the Law of the Sea entitled the coastal States to naturally extend the continental shelf, which has caused more drastic disputes of maritime delimitation. This paper devotes to clarifying the significant concept of natural prolongation through an effect method combing the legal principles and technical analysis. Firstly, the classic samples with respect of the development of geological features are traced. Based on these samples, the classification with a model is proposed in order to affirm the concept＇s significance under certain geomorphologic situations. Lastly, scientific analysis is used to present two potential prolongation situations and emphasize that all the technical analysis on maritime delimitation should be complied with international law and protect the common interest of all the mankind.
文摘BACKGROUND QTc interval prolongation with an increased risk of torsade de pointes(Tsd)has been described in coronavirus disease 2019(COVID-19)patients treated with hydroxychloroquine(HCQ)and azithromycin(AZI)in Western countries.In the DR Congo,few studies have evaluated the safety of this association or proposed new molecules.AIM To determine the incidence of QTc prolongation and Tsd in COVID-19 patients treated with HCQ-AZIs vs doubase C(new molecule).METHODS In present randomized clinical trial,we have included patients with mild or moderate COVID-19 treated with either HCQ-AZI or doubase C.Electrocardiogram(ECG)changes on day 14 of randomization were determined based on pretreatment tracing.Prolonged QTc was defined as≥500 ms on day 14 or an increase of≥80 ms compared to pretreatment tracing.Patients with cardiac disease,those undergoing other treatments likely to prolong QTc,and those with disturbed ECG tracings were excluded from the study.RESULTS The study included 258 patients(mean age 41±15 years;52%men;3.4%diabetics,11.1%hypertensive).Mild and moderate COVID-19 were found in 93.5%and 6.5%of patients,respectively.At baseline,all patients had normal sinus rhythm,a mean heart rate 78±13/min,mean PR space 170±28 ms,mean QRS 76±13 ms,and mean QTc 405±30 ms.No complaints suggesting cardiac involvement were reported during or after treatment.Only four patients(1.5%)experienced QTc interval prolongation beyond 500 ms.Similarly,only five patients(1.9%)had an increase in the QTc interval of more than 80 ms.QTc prolongation was more significant in younger patients,those with high viral load at baseline,and those receiving HCQ-AZI(P<0.05).None of the patients developed Tsd.CONCLUSION QTc prolongation without Tsd was observed at a lower frequency in patients treated with HCQ-AZI vs doubase C.The absence of comorbidities and concurrent use of other products that are likely to cause arrhythmia may explain our results.
