QT Interval In Patients Research Articles

QT Interval in Patients With COVID-19

Since the first case recorded in the end of 2019, the virus SARS-CоV-2 and the related lung disease COVID-19 have spread over the world and became a threat for public health. The drugs used for treatment of this disease (azithromycin and hydroxychloroquine) can prolong the QT interval on the electrocardiogram to increase the risk of pirouette tachycardia and sudden cardiac death. This article presents a review of potential risks related with the drug treatment of COVID-19 and provides recommendations for management of patients during the pandemic.

Safety of antiviral and anti-inflammatory drugs prolonging QT interval in patients with coronavirus disease 2019: an opinion of the Heart Rhythm Section of the Polish Cardiac Society.

Safety of antiviral and anti-inflammatory drugs prolonging QT interval in patients with coronavirus disease 2019: an opinion of the Heart Rhythm Section of the Polish Cardiac Society.

Chloroquine-induced torsades de pointes in a patient with coronavirus disease 2019

Chloroquine-induced torsades de pointes in a patient with coronavirus disease 2019

QT interval and corrected QT interval in patients with sepsis in correlation with sepsis outcome and electrolytes

Abstract Background sepsis is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. Common signs and symptoms of sepsis include fever, increased heart rate, increased breathing rate, and confusion. In the very young, old, and people with a weakened immune system, there may be no specific symptoms. Aim to study QT dispersion, QT interval abnormalities and corrected QT interval in septic patients in correlation with arrhythmias, hospital outcome (survival, mortality) and electrolytes. Patients and Methodology this is a prospective randomized study that was conducted on forty adult patients who were admitted in the ICU at Ahmed Maher Teaching Hospital with the diagnosis of sepsis to correlate Corrected QT interval (QTc) and QT dispersion (QTD) with arrhythmias, need for mechanical ventilation (MV), electrolytes and hospital outcome. Results forty patients were included in this study, their ages with a mean of 53.50± 13.7 years. Male patients were 24(60%) and female patients were 16 (40%). The most frequent risk factor was hypertension (62.5%). Conclusions the QTc duration may act as a risk marker in the septic patient. Patients with markedly prolonged QTc interval had significantly more episodes of inhospital ventricular tachycardia and hospital mortality. Recommendations QTc may add a useful, simple and accessible tool to be used in risk stratification of septic patients. Factors that cause QTc prolongation could be an avoidable or correctable factors; lifethreatening arrhythmia could be prevented.

Elevated Plasma Adiponectin Levels Are Associated with Abnormal Corrected QT Interval in Patients with Stable Angina.

Low-circulating levels of adiponectin (ADPN) are associated with obesity, diabetes mellitus, and coronary artery disease. On the contrary, some studies have demonstrated a link between relatively high levels of plasma ADPN and heart failure, atrial fibrillation, and adverse outcome. However, little is known about the relationship between ADPN level and prolonged QT interval. The aim of this study was to investigate the association between plasma ADPN levels and prolonged QT interval in patients with stable angina.In this retrospective study, because the diverse disease severity and condition of the study population may have affected the results, we chose individuals with stable angina. Plasma ADPN concentrations were measured using enzyme-linked immunosorbent assays. A 12-lead ECG recording was obtained from each patient.We enrolled 479 stable-angina patients. Patients with an abnormal corrected QT (QTc) interval had higher median plasma ADPN levels than those with normal QTc intervals. Age- and sex-adjusted ADPN levels were positively associated with heart rate, QTc interval, left ventricular mass index, and creatinine but negatively associated with left ventricular ejection fraction, waist circumference, current smoking, total cholesterol, triglycerides, low-density lipoprotein cholesterol, albumin, and estimated glomerular filtration rate. A multiple logistic regression analysis revealed ADPN as an independent association factor for abnormal QTc interval. Increasing concentrations of sex-specific ADPN were independently and significantly associated with abnormal QTc interval, even after full adjustment of known biomarkers.Our results indicate that ADPN may play a role in the pathogenesis of abnormal QTc interval in patients with stable angina.

Severe iatrogenic hypoglycaemia requiring medical assistance is associated with concurrent prolongation of the QTc interval

AimsHypoglycaemia has been shown to exert arrhythmogenic effects. Herein, we explore the association between severe hypoglycaemia requiring medical assistance and the length of the QT interval in patients with diabetes. MethodsData from a prospective study, conducted in eight tertiary hospitals, which recorded cases of hypoglycaemia from patients with diabetes seeking treatment at emergency departments (ED) were analyzed. The patients’ electrocardiograms (ECGs), were compared to those of non-hypoglycaemic diabetic individuals, matched for age, gender and duration of diabetes, obtained during their scheduled follow-up visits. The corrected QT intervals (QTc) were calculated blindly by two cardiologists. ResultsECGs from 154 patients presenting with hypoglycaemia were analyzed and compared to 95 matched controls. The mean QTc interval was significantly longer in patients with hypoglycaemia than in controls (441.9 ± 48.2 vs. 401.0 ± 29.6 ms, p < 0.001) A significantly higher proportion of hypoglycaemic patients had an abnormally prolonged QTc (≥440 ms) compared to controls (49.4% vs. 11.6%, p < 0.001). Among patients with hypoglycaemia, there was a statistically significant but rather weak negative correlation between QTc interval and plasma glucose at presentation (r: −0.183, p = 0.02). ConclusionsIn diabetic patients, hypoglycemia requiring medical assistance is associated with a significant prolongation of the QTc interval. The degree of this prolongation is associated with hypoglycaemia severity.

Assessment of the Relationship Between Dose and Number of Effective Used Drugs on on QT Interval in Patients with Lupus

Background: Systemic lupus erythematosus is an autoimmune and multi-organ disease. Cardiovascular involvement is one of most important causes of death in these patients. In some studies, it has been observed that the prolongation of the QTc interval is a prognostic factor in cardiovascular failure. Objectives: In this study, we intended to assess the role of drugs used in treating patients with lupus on the prolonged QTc interval. Methods: This descriptive-analytical study was carried out on 150 patients with SLE referring to Rheumatology Clinics in the City of Arak during 2014 and 2015. Then, ECGs were taken from all patients in two phases, first on admission and second six hours later. The QTc interval was determined using Bazett’s formula. The results were analyzed using SPSS version 16 software. Results: The mean age of the studied patients was 35.36 ± 11.8 years and 80.7% were females. An anti-Ro/SSA antibody and treatment with hydroxychloroquine were significantly associated with the prolongation of QTc in patients; however, the duration and dosage of hydroxychloroquine did not affect the QTc interval. Conclusions: Based on the obtained results, hydroxychloroquine may influence the cardiac condition of patients; thus, it needs more studies in this field.

Оценка длительности интервала QT у пациентов с COVID-19 на фоне лечения гидроксихлорохином и азитромицином

At the end of 2019, an outbreak of a novel coronavirus infection occurred in PRC, the causative agent of which was given the temporary name 2019-nCoV. COVID-19 is a complex multisystem disease which causes harmful effects not only on the lungs, but also on the cardiac conduction system. Aim. To assess the duration of corrected QT interval in patients with COVID-19 during treatment with hydroxychloroquine and azithromycin, and to identify the relationship between this indicator and the severity of interstitial pneumonitis. Materials and methods. We studied medical records of 40 men and 4 women, who were treated in the infectious diseases department of Acad. N.N. Burdenko Main Military Clinical Hospital from March 20 to May 20, 2020. All patients underwent resting digital 12-lead electrocardiography: at the time of admission to the hospital and after 6 days of therapy using the "Myocard-12" system. In our study, 30 patients were treated with azithromycin at a total daily dose of 500 mg for 5 to 10 days; 21 patients – with hydroxychloroquine at a dose of 400 mg 2 times a day on the 1st day of treatment and 200 mg 2 times a day for the next 5 days; and 7 patients received azithromycin and hydroxychroloquine combination. Results. To assess the duration of corrected QT interval depending on the severity of patient's status and the degree of lung damage, we compared the mean QT interval depending on the degree of lung damage on computed tomography. There was no significant difference in this indicator in patients with pneumonia of varying severity. However, when using the combination of azithromycin and hydroxychloroquine after 6 days, there was a significant increase in the mean cor-rected QT interval compared to its baseline value (before treatment). Conclusion. Patients hospitalized with COVID-19 have an initially prolonged corrected QT interval. The combined use of azithromycin and hydroxychloroquine in a short time causes a significant increase in the corrected QT interval in patients with COVID-19.

Changing QT interval in orthostasis — new diagnostic marker of syndrome of extended QT interval

Long QT interval syndrome (LQTS) is a disease that causes life-threatening arrhythmias and sudden death syndrome. Recently, it has been shown that about half of patients with LQTS have normal QTc interval values on an ECG. The purpose of this study was to assess changes in the QT interval in patients with LQTS in orthostasis to identify additional criteria for the disease. Surveyed 64 patients from 4 to 47 years old (13.3 ± 10.0) with LQTIS. The control group consisted of 87 healthy people of 4–20 years (11.0 ± 3.5). An ECG was performed in a lying and standing position. HR, QT and QTc interrvals in both positions and the difference between these indicators were evaluated. In both groups, we noted an increase in heart rate and QTc and a shortening of the QT interval in orthostasis. Distinctions between all parameters were revealed reliably, except for the increase in the QTc interval (∆QTc) in the main and control groups. ROC analysis revealed that the optimal point for identifying patients with LQTS is QTc interval in orthostasis –500 ms with Se 73 % and Sp 93 %. Conclusions. In the early period of orthostasis, an increase in the heart rate, a shortening of the QT interval and a prolongation of the QTc interval occur; lengthening the QTc interval in the early period of orthostasis over 500 ms is highly sensitive and highly specific in identifying patients with the syndrome of prolonged QT-interval.

Prolonged QT Interval in Patients Receiving Psychotropic Medications.

INTRODUCTION: Prolonged QT interval (PQTI) is a cardiac condition widely documented in the mental health literature and linked to psychotropic medication use. Medications notable for contributing to the condition are antipsychotics, antidepressants, and some mood stabilizers. Although additional medication classes and other contributing risk factors are often present, the prudent mental health provider benefits from having a basic understanding of this condition and how to prevent and manage it with safe prescribing practices. AIMS: This guide seeks to provide mental health prescribers with a basic understanding of the risk factors, pathophysiology, identification, and management of PQTI. METHOD: Relevant literature and practice guidelines were reviewed and summarized with a focus on practical interventions for the psychiatric mental health nurse practitioner (PMHNP). RESULTS: One of the primary contributing factors to PQTI development and complications is polypharmacy. Patients with co-occurring medical, mental health, and/or substance use disorders may receive medications from multiple providers. Anticancer drugs, antiarrhythmic medications, and even a number of common antibiotics can increase the QT interval, making it a challenge for even the most experienced mental health provider to monitor medication interactions and side effects that contribute to PQTI. Having a sound knowledge base of these factors can guide safe PMHNP practice. CONCLUSIONS: Decision-making trees grounded in evidence-based research were developed in order to direct thorough assessment and safe treatment of patients requiring psychotropic medications.

The QT Interval Dynamic in a Human Experimental Model of Controlled Heart Rate and QRS Widening.

Background: there is increasing interest for computing corrected QT intervals in patients with prolonged depolarization. We aimed to analyze the effect of prolonged QRS in the QT and in the diagnostic accuracy of frequency-correction. Methods and Results: in 28 patients admitted for self-expanding aortic valve implantation, sequential pacing was performed in the AAI mode in two different phases: before and immediately after the release of the prosthesis. We evaluated the accuracy of the Bazett, Fridericia, Framingham and Hodges formulas with the reference of the QT at 60 bpm (QTc/deviation). The widening of the QRS was the main contributor to the QT prolongation (Pearson 0.79; CI95%: 0.75–0.84). Prolongation in other intervals (ST segment and T-wave) significantly contribute in the higher frequency range (p < 0.05). The Bazett’s formula displayed the highest QTc/deviation, while Framingham and Hodges retrieved the lowest QTc/deviation and the best fit (p < 0.001). In addition, the Bazett’s formula displayed the highest correlation between variations in the QTc/deviation and the widening of the QRS (Pearson coefficient −0.54; p < 0.001) in comparison with the Fridericia, Framingham and Hodges formulas (−0.51, −0.37 and −0.38 respectively; p < 0.001). There was also a linear effect of the heart rate in the QTc/deviation obtained with the Bazett’s formula (p = 0.015), not observed for other formulas. Conclusions: The prolonged depolarization of the ventricles introduces direct and linear prolongation in the QT interval, but also a non-linear distortion in cardiac repolarization that contributes for QT prolongation at the higher frequency range. The Bazett’s formula displays significantly higher sensitivity to prolongation of ECG intervals.

Prevalence of prolonged QT interval in patients with HCV-related chronic liver disease

BackgroundHepatitis C virus (HCV) is a common disease in Egypt with a high socioeconomic burden and extra-hepatic manifestations as QT prolongation, but previous studies included mainly patients with advanced liver disease, so in this study, we aimed to delineate the prevalence of QT prolongation in early-stage HCV patients.ResultsThe study included 874 HCV patients with early cirrhosis; in Child’s class A, 57 (6.5%) patients had prolonged QT interval corrected (QTc). There was significant higher proportion of cirrhotic patients in the prolonged QTc group (31.6%) vs. in the normal QTc group (11.5%). QTc was 424.39 ± 36.6 vs. 411.51 ± 32.89 ms in cirrhotic and non-cirrhotic patients, respectively (P, 0.001). There was significant higher proportion of Fibrosis 4 (FIB-4) ≥ 1.45 score in the prolonged QTc (77.2%) vs. in the normal QTc group (56.8%) (P, 0.003). QTc interval was 417.76 ± 34.12 ms in patients with FIB-4 score ≥ 1.45 vs. 406.78 ± 31.95 ms in those with FIB-4 < 1.45 (P, < 0.001). FIB-4 score value of 2.108 predicted prolonged QTc with a sensitivity of 63.2% and a specificity of 64.5% (P, < 0.001). Twenty-four patients of long QTc group sent ECGs after HCV eradication, and 19 patients (79%) showed QTc normalization.ConclusionsHCV is associated with QTc prolongation even in patients with early chronic liver disease stages without significant fibrosis. Also, it is related to the degree of fibrosis and cirrhosis. At a cutoff value of 2.108, FIB-4 score can predict prolonged QTc. HCV eradication is associated with a high incidence of QTc normalization.

Prognostic importance of the QT interval in patients with chronic kidney disease 5d stage

The aim : to clarify the safe range of the values of the corrected QT interval and to identify risk factors that contribute to its increase in patients with end-stage renal disease who receive treatment with programmed hemodialysis (HD). Patients and methods . 70 patients (26 men and 44 women) with end-stage renal disease receiving HD were observed for 5 years. The average age was 58.5 ± 14.7 years. A traditional clinical and laboratory examination, echocardiography was performed in all patients. The value of the QT interval corrected for the frequency of ventricular contractions was calculated using the Framingham formula. The patients were clinically stable, there were no violations of heart rhythm and conduction requiring medical correction. Results. During 5 years of observation, 23 patients died. Given the different number of men and women among the surveyed, mortality rates were calculated separately for each of the gender groups. For men, mortality was 27% or 6.7 per 100 patient-years (6.7 per 100 people per year). For women, respectively, 36.4% or 8.5 per 100 patient-years (8.5 per 100 people per year). The chance of sudden cardiac death for men was 0.37, for women - 0.57. Thus, the risk of sudden cardiac death in women was 1.5 times higher than in men. The guidelines for the QT interval are proposed for the general population. We calculated the prognostic value of the QT interval in relation to sudden cardiac death in our patients was 440 msec or more; the area under the ROC curve is 0.978 (95% CI 0.911-0.998), p = 0.0001. Sensitivity 95.6%, specificity 100%. A number of identifiable indicators during the five-year observation period has changed (delta). There were identified correlations between the value of QT and the delta of body mass index Rs = -0.458 p = 0.002; delta of hemoglobin Rs = -0,338 p = 0.025; delta width of the distribution of platelets by volume Rs = 0.377 p = 0.011. Conclusion. The data of our study allow us to offer for practical application a dynamics study of the PQ interval in comparison with the dynamics of body mass index, hemoglobin level and the width of the distribution of platelets by volume. This approach seems to us very important primarily in clinically stable patients with the PQ ≥ 440 msec interval corrected for the frequency of ventricular contractions.

Drug-induced prolonged corrected QT interval in patients with methadone and opium overdose

BackgroundIran is a country with the highest rate of opioid addiction in the world. The most commonly used opioid in Iran is opium, and methadone is in second place. The trend of drug use has changed from opium to methadone from 2006 to 2011. Presence of a large number of addicted people and methadone maintenance therapy clinics make methadone readily available in Iran. Therefore, evaluation of the epidemiological characteristic of methadone toxicity and its effects on the heart is essential.MethodsIn This cross-sectional, retrospective, descriptive, analytical study all patients with methadone or opium toxicity who had been admitted to Vasei hospital, Sabzevar, Iran, during the years 2015 and 2016 were included, and their records were evaluated. Demographic data, addiction history, underlying diseases, and the outcome of admission were recorded. Then, corrected QT interval (QTc) of the first ECG of the patients after admission was evaluated.ResultsThe Majority of toxicities occurred in those above 30 years of age (71.4%), who lived in cities (62.8%), and were married (69.2%). A positive history of addiction was considerably higher in the opium group (72.3% versus 43.3%). There was no significant difference regarding QTc prolongation between patients with methadone and opium toxicity (p = 0.3).ConclusionQTc prolongation is one of the adverse effects of methadone or opium overdose. It seems that significant QTc prolongation is not uncommon among patients with opium overdose.

Effect of spinal anesthesia on the QT interval in term and post-term pregnancies scheduled for elective cesarean section: a prospective study

Objectives: In this study, we aimed to investigate the effects of spinal anesthesia on the QT interval in patients with term and post-term pregnancy that were scheduled for elective cesarean section. Materials and methods: Forty pregnant women scheduled for elective cesarean section under spinal anesthesia were assigned into two groups: Post-term group (Group P) (n = 20) and Term group (Group T) (n = 20). After entering the operation room, standard monitoring [electrocardiography (ECG), noninvasive blood pressure, heart rate, respiratory rate, and peripheral oxygen saturation] was performed. The patient was placed in the sitting position and spinal anesthesia was performed with a median approach at the L3–L4a level using a 25G Quincke-type spinal needle. After cerebrospinal fluid was viewed, 12.5 mg (2.5 mL) hyperbaric bupivacaine was administered intrathecally over 1 min. Other ECG records were made at min 1 (T1), 5 (T2), and 10 (T3) after the induction of spinal anesthesia and after skin closure (T4). QT and QT dispersion were measured from ECG. Heart rate-corrected QT (QTc) and QT dispersion (QTcd) values were calculated using the Bazett formula. Results: Demographic characteristics of the patients were similar in both groups. Postoperative QTc, QTd, and QTcd values were significantly increased in Group P compared to those in Group T (p < .05). Conclusion: Spinal anesthesia led to increased postoperative QTc, QTd, and QTcd values in the patients with a gestational age of ≥42 weeks who underwent cesarean section. Accordingly, it is advisable to perform postoperative strict cardiac monitoring particularly in post-term pregnant women undergoing spinal anesthesia.

Analysis of effect of antidepressant drug venlafaxine on length of QT interval in patients with depressive disorder and alcohol dependence

&amp;lt;p&amp;gt;Introduction. Depressive disorder is common in patients with the diagnosis of alcoholism. Comorbidity of depression and alcoholism significantly worsens the clinical status of patients and represents a major therapeutic challenge. The aim of the study was to investigate the effect of the antidepressant drug venlafaxine on the length of QT interval in patients with depressive disorder and alcohol dependence. Methods. The research included 49 male patients (&amp;amp;gt;18 years of age) with alcohol dependence, who were also diagnosed with depressive disorder by using DSM-IV criterion and positive Hamilton Rating Scale for Depression (HRSD) at the very beginning of hospitalization. The patients had been given 37.5 mg of the antidepressant drug venlafaxine twice a day for twenty days. The global QTc interval (12 leads) was determined automatically using ECG device Schiller Cardiovit AT-1, which used &amp;quot;SCHILLER ECG Measurement and Interpretation Software for Children and Adult ECGs&amp;quot;. Statistical data processing was performed using SPSS 16.0 programme package for Windows. Results. There was a statistically significant positive association between HRSD score (depression intensity) and the serum levels of creatine kinase isoenzyme MB, i.e. the degree of myocardial damage (p = 0.048). A statistically significant positive correlation between serum gamma-glutamyltransferase levels and the length of QTc interval (p &amp;amp;lt; 0.001) was also found. There was no statistically significant difference in the length of QTc interval before and after venlafaxine administration (p = 0.827), and the average prolongation of the QTc interval was 0.776 ms (95% CI = -6.323 ms-7.874 ms). Conclusion. In our study, we did not prove the negative effect of antidepressant drug venlafaxine on QT interval in patients with depressive disorder and alcohol dependence. In patients with alcohol dependence, the therapy for depression must have a priority due to the proven negative association between depression and the degree of myocardial damage.&amp;lt;/p&amp;gt;

Анализ интервала QT у больных с ишемическим инсультом

Анализ интервала QT у больных с ишемическим инсультом

Serum albumin level and abnormal corrected QT interval in patients with coronary artery disease and chronic kidney disease.

Lower concentrations of serum albumin appear to be associated with an increased risk of all-cause and cardiovascular mortality, coronary heart disease, heart failure and stroke. However, little is known about the relationship between serum albumin level and prolonged QT interval. To investigate whether lower serum albumin is associated with prolonged QT interval by recording 12-lead electrocardiography in patients with coronary artery disease and chronic kidney disease. This study included 1383 consecutive patients with coronary artery disease and chronic kidney disease (841 with acute coronary syndrome and 542 with elective percutaneous coronary intervention patients) who were enrolled in a disease management programme. Twelve-lead electrocardiography was recorded in each subject. We assessed the relationship between albumin levels (both as a continuous variable and stratified by tertile) at admission and corrected QT (QTc) prolongation. Patients with abnormal QTc interval had lower serum albumin levels than those with normal and borderline QTc intervals. Statistically significant negative associations were observed between serum albumin levels and QTc interval (β = -0.211, P < 0.0001). Using multivariate and trend analyses, a lower concentration of serum albumin was independently associated with QTc prolongation in both the patients with acute coronary syndrome and elective percutaneous coronary intervention patients. Concentrations of serum albumin were significantly lower in the patients with an abnormal QTc interval and were associated with QTc prolongation. Further studies are needed to clarify whether lower serum albumin plays a role in the pathogenesis of QTc prolongation.

Prolongation of the QT interval in patients with coronary heart disease as consequence of drug-drug interactions on metabolic rate

Objective:Prolongation of the QT interval in patients with coronary heart disease (CAD) is a risk factor of polymorphic ventricular tachycardia (PVT) and as consequence, the sudden death. Drug-drug interactions (DDI) on metabolic rate involving cytochrome P-450 (CYP) is the one of the major cause of Long QT Syndrome (LQTS). The aim of the present study was to improve the safety of combined pharmacotherapy when using drugs that affect the QT interval.Method and Results:Medication occurrence of potential dangerous combination of medicines that are affected on QT interval duration in patients with CAD are researched (outpatient medical records (patient history) analysis). Clinical relevance of DDI, which are associated with changes in CYP enzyme activity, categorized by drugs.com Medication Guide. Finding potential dangerous combination of medicines that are affected on QT interval duration were administered to patients with CAD in 3.6% cases in outpatient clinical practice. The most often prescribed combination of drugs is amiodarone and torasemide (13.3% evidence of all concomitant administration that are leading to QT prolongation). The potential mechanism of Amiodarone and Torasemide interaction on metabolic rate that are leading to QT prolongation are competitive substrates CYP 2C8 and a result of inhibited CYP 2C9 by amiodarone.Conclusion:Ability to predict the prolongation of the QT interval caused by DDI on metabolic rate make possible to improve the safety concomitant administration to patients with CAD.

Effects of lappaconitine hydrobromide on qt interval in patients with paroxysmal atrial fibrillation

84 patients aged 40 to 70 years received Holter ECG monitoring to determine the values of QT’interval measurement. All patients were divided into 4 groups: group 1 – 24 healthy patients, group 2 – (n = 24) patients with ischemic heart disease (IHD) without indication to atrial fibrillation (AF), group 3 (n = 20) patients with IHD with AF using amiodarone for prevention of AF at a dose 200 mg/day, 5 days a week, group 4 (n = 16) – patients with IHD with AF using lappaconitine hydrobromide for prevention of AF at a dose of 25 mg 3 times a day. In the groups, QTav. varied from 391.78 ± 6.60 ms (in healthy subjects) to 437.13 ± 7.16 ms (on the top of amiodarone therapy). But despite a significant increase in this parameter in patients with IHD without AF, QTav. interval remained within the normal limits on the top of lappaconitine hydrobromide and amiodarone therapy compared with the healthy subjects group. The QTc interval was recorded from 389.20 ± 9.32 ms (IHD without FP) to 421.88 ± 6.08 ms (on the top of amiodarone therapy) in the groups. This parameter was not significantly different across the groups and remained within the normal limits. The QTd interval spread was from 14.75 ± 2.00 ms (on the top of amiodarone therapy) to 32.50 ± 11.26 ms (on the top of of lappaconitine hydrobromide therapy) in the groups. Despite the fact that this parameter was significantly higher on the top of lappaconitine hydrobromide therapy, it did not go beyond the normal limits either.