QTc Interval In Patients Research Articles

A Comparative Analysis of the Effects of Haloperidol and Dexmedetomidine on QTc Interval Prolongation during Delirium Treatment in Intensive Care Units.

Haloperidol and dexmedetomidine are used to treat delirium in the intensive care unit (ICU). The effects of these drugs on the corrected QT (QTc) interval have not been compared before. It was aimed to compare the effects of haloperidol and dexmedetomidine treatment on QTc intervals in patients who developed delirium during ICU follow-up. The study is single-center, randomized, and prospective. Half of the patients diagnosed with delirium in the ICU were treated with haloperidol and the other half with dexmedetomidine. The QTc interval was measured in the treatment groups before and after drug treatment. The study's primary endpoints were maximal QT and QTc interval changes after drug administration. 90 patients were included in the study, the mean age was 75.2±12.9 years, and half were women. The mean time to delirium was 142+173.8 hours, and 53.3% of the patients died during their ICU follow-up. The most common reason for hospitalization in the ICU was sepsis (%37.8.). There was no significant change in QT and QTc interval after dexmedetomidine treatment (QT: 360.5±81.7, 352.0±67.0, p= 0.491; QTc: 409.4±63.1, 409.8±49.7, p=0.974). There was a significant increase in both QT and QTc interval after haloperidol treatment (QT: 363.2±51.1, 384.6±59.2, p=0.028; QTc: 409.4±50.9, 427.3±45.9, p=0.020). Based on the results obtained from the study, it can be concluded that the administration of haloperidol was associated with a significant increase in QT and QTc interval. In contrast, the administration of dexmedetomidine did not cause a significant change in QT and QTc interval.

A look into prolonged Qtc Interval in Patients undergoing Long-Term Hemodialysis at Ibn Sina Hospital, Khartoum, Sudan - 2020

A look into prolonged Qtc Interval in Patients undergoing Long-Term Hemodialysis at Ibn Sina Hospital, Khartoum, Sudan - 2020

Evaluation of the Relationship between QT Interval in ECG and GRACE Score Amount of Hospitalized Patients with NSTEMI.

Non-ST-elevation myocardial infarction (NSTEMI) is a significant component of acute coronary syndrome (ACS) and typically exhibits a relative incidence that is more than double that of ST-segment elevation myocardial infarction (STEMI). Data obtained from the International Long QT Syndrome Registry indicate that the risk of developing malignant arrhythmias in individuals with long QT syndrome is exponentially associated with the duration of the QTc interval. Therefore, the aim of this study was to assess the potential inclusion of prolonged QTc as a prognostic risk factor in NSTEMI patients. A cross-sectional study was conducted on patients with NSTEMI diagnosis admitted to the Bu-Ali Hospital of Qazvin between April 2021 and September 2021 by census method. The QT interval was measured in the electrocardiogram at admission. The documented grace score was calculated and its relationship with the corrected QTc interval was estimated using the Hodges formula. Finally, the relationship between QTc and GRACE score was investigated as a prognostic factor in ACS patients. Relationships were assessed by using both the T-test and the chi-square test. A total of 60 patients (31.7% females, 63.8% males) with a mean age of 63 ± 12.7 years were evaluated. Most of the patients (68.3%) were at low risk regarding the Grace score category. In evaluating the relationship between QTc in the electrocardiogram at admission with total GRACE score, the Pearson correlation results were significant and there was a positive relationship between these two factors (r = 0.497, P < 0.001). This study revealed a significant relationship between the QTc interval of patients and the GRACE Score. It was shown patients' QTc can be a predictive factor of patients' mortality.

Pharmacist Reported Protocols for QTc Monitoring of Psychiatric Medications.

Background Psychiatric medications, such as antipsychotics and antidepressants, are associated with QTc interval prolongation. There is currently no consensus best practice on how to mitigate this risk. This study aimed to collect and analyze information about methods used for QTc monitoring in patients taking psychiatric medications to better understand current practice. Methods An anonymous electronic survey was distributed on September 22, 2022, using a national psychiatric pharmacist organization email list. The survey closed on December 15, 2022. Descriptive statistics were used to analyze the multiple-choice questions. Qualitative analysis applying grounded theory for thematic analysis was performed forfree response questions. Results A total of 48 initiated the survey. Of the respondents, 11.4% (5/44) reported that their institution had a formal protocol for monitoring QTc intervals in patients receiving psychiatric medications, while 32.4% (12/37) reported that their institution had an informal process. Out of those with a protocol or process, approximately half reported that it was drug-specific. Among the respondents, 88.6% (31/35) reported that there was a psychiatric clinical pharmacy specialist at their institutionand 34.3% (12/35) reported that pharmacists could order an electrocardiogram (ECG). Major themes that emerged from the qualitative analysis included pharmacist-driven QTc monitoring, referring the patient to another provider for monitoring, and encountering significant barriers to monitoring. Conclusion A variety of methodsare currently being employed to monitor QTc prolongation risk in patients taking psychiatric medications. Pharmacist authorization to order ECGs may be an opportunity to advance practice and improve care for this population. Further research is needed to more clearly understand best practices for QTc prolongation risk mitigation in patients receiving psychiatric medications.

Antipsychotics and the QTc Interval During Delirium in the Intensive Care Unit

Antipsychotic medications, often prescribed for delirium in intensive care units (ICUs), may contribute to QTc interval prolongation. To determine whether antipsychotics increase the QTc interval in patients with delirium in the ICU. An a priori analysis of a randomized clinical trial in medical/surgical ICUs within 16 centers across the US was conducted. Participants included adults with delirium in the ICU with baseline QTc interval less than 550 ms. The study was conducted from December 2011 to August 2017. Data analysis was performed from April 25 to August 18, 2021. Patients were randomized 1:1:1 to intravenous haloperidol, ziprasidone, or saline placebo administered twice daily until resolution of delirium, ICU discharge, or 14 days. Twelve-lead electrocardiograms were used to measure baseline QTc before study drug initiation and telemetry was used to measure QTc before each subsequent dose of study drug. Unadjusted day-to-day changes in QTc were calculated and multivariable proportional odds regression was used to estimate the effects of antipsychotics vs placebo on next-day maximum QTc interval, adjusting for prespecified baseline covariates and potential interactions with sex. Safety end points, including the occurrence of torsade de pointes, were evaluated. All analyses were conducted based on the intention to treat principle. A total of 566 patients were randomized to haloperidol (n = 192), ziprasidone (n = 190), or placebo (n = 184). Median age was 60.1 (IQR, 51.4-68.7) years; 323 were men (57%). Baseline median QTc intervals across the groups were similar: haloperidol, 458.0 (IQR, 432.0-479.0) ms; ziprasidone, 451.0 (IQR, 424.0-472.0) ms; and placebo, 452.0 (IQR, 432.0-472.0) ms. From day 1 to day 2, median QTc changed minimally: haloperidol, -1.0 (IQR, -28.0 to 15.0) ms; ziprasidone, 0 (IQR, -23.0 to 20.0) ms; and placebo, -3.5 (IQR, -24.8 to 17.0) ms. Compared with placebo, neither haloperidol (odds ratio [OR], 0.95; 95% CI, 0.66-1.37; P = .78) nor ziprasidone (OR, 1.09; 95% CI, 0.75-1.57; P = .78) was associated with next-day QTc intervals. Effects were not significantly modified by sex (P = .41 for interaction). There were 2 occurrences of nonfatal torsade de pointes, both in the haloperidol group. Neither was associated with study drug administration. The findings of this trial suggest that daily QTc interval monitoring during antipsychotic use may have limited value in patients in the ICU with normal baseline QTc and few risk factors for QTc prolongation. ClinicalTrials.gov Identifier: NCT01211522.

(003) Antipsychotics effects on PR, QRS, and QTc Intervals in Patients with Wolff-Parkinson-White Syndrome With and Without Cardiac Ablation

(003) Antipsychotics effects on PR, QRS, and QTc Intervals in Patients with Wolff-Parkinson-White Syndrome With and Without Cardiac Ablation

Adavosertib (AZD1775) does not prolong the QTc interval in patients with advanced solid tumors: a phase I open-label study

PurposeAdavosertib is a small-molecule, ATP-competitive inhibitor of Wee1 kinase. Molecularly targeted oncology agents have the potential to increase the risk of cardiovascular events, including prolongation of QT interval and associated cardiac arrhythmias. This study investigated the effect of adavosertib on the QTc interval in patients with advanced solid tumors.MethodsEligible patients were ≥ 18 years of age with advanced solid tumors for which no standard therapy existed. Patients received adavosertib 225 mg twice daily on days 1–2 at 12-h intervals and once on day 3. Patients underwent digital 12-lead electrocardiogram and pharmacokinetic assessments pre-administration and time-matched assessments during the drug administration period. The relationship between maximum plasma drug concentration (Cmax) and baseline-adjusted corrected QT interval by Fridericia (QTcF) was estimated using a prespecified linear mixed-effects model.ResultsTwenty-one patients received adavosertib. Concentration–QT modeling of ΔQTcF and the upper limit of the 90% confidence interval corresponding to the geometric mean of Cmax observed on days 1 and 3 were below the threshold for regulatory concern (not > 10 ms). No significant relationship between ΔQTcF (vs baseline) and adavosertib concentration was identified (P = 0.27). Pharmacokinetics and the adverse event (AE) profile were consistent with previous studies at this dose. Eleven (52.4%) patients experienced 17 treatment-related AEs in total, including diarrhea and nausea (both reported in six [28.6%] patients), vomiting (reported in two [9.5%] patients), anemia, decreased appetite, and constipation (all reported in one [4.8%] patient).ConclusionAdavosertib does not have a clinically important effect on QTc prolongation.ClinicalTrials.govNCT03333824.

Usefulness of electrocardiography QT interval for prediction of left ventricular diastolic dysfunction: a cross-sectional study.

A cross-sectional at Holy-family Hospital, Rawalpindi Medical University, Pakistan. One thousand five hundred patients were referred for electrocardiography (ECG) for clinical suspicion of HF between May and July 2022. Ejection fraction (EF), lateral mitral annulus velocity (e'), mitral inflow early (E) and late (A) velocities, left ventricular filling pressure (E/e' ratio), and QT interval (QTc) was calculated. Odds ratios with a 95% CI (odds) were obtained by comparing QTc with all variables. The patients were mostly middle-aged adults with a mean age of 30.27 (±7.64). Male to female ratio was nearly balanced, with 771 (51.4%) males included in the clinical survey. The ECG parameters were; QT interval-494.07 (±63.61), EF-57.11 (±11.96), early to atrial filling velocity ratio-0.71 (±0.20), and lateral mitral annulus velocity-8.29 (±1.64). The promising results for correlation between QT interval and ECG parameters, particularly EF and lateral mitral annulus velocity, should not be considered as the alternative in diagnosing left ventricular diastolic dysfunction thus far. Prolonged electrocardiographic QTc interval in patients with HF is useful in predicting diastolic dysfunction.

Factors of QTc interval prolongation in patients with arterial hypertension

The relevance of determining the factors of the prolonged QTc interval development in patients with arterial hypertension is high, as it solves the issue of preliminary diagnosis among patients from risk groups and allows adjusting the diagnostic and therapeutic tactics of managing such patients. Aim: to determine factors for the development of prolonged average daily QTc interval in patients with arterial hypertension. Materials and methods. The study included 195 patients with arterial hypertension, who were divided into 2 subgroups: 175 individuals with a normal average daily duration of the QTc interval and 20 patients with a prolonged average daily duration of the QTc interval. All the patients underwent 24-hour heart rate monitoring and determination of blood pressure variability. At the stage of involving patients in the study, the following were performed: anamnesis collection and determination of physical data (estimation of systolic and diastolic blood pressure). Results. The study has revealed risk factors of daily QTc interval prolongation in hypertensive patients with further developing a prognostic model with high sensitivity (88.9 %) and specificity (70.6 %). Prolongation of QTc in patients with hypertension was associated with such parameters: male sex (OR = 4.292 [95.0 % CI 1.337–13.779], Р = 0.014), body mass index (OR = 1.107 [95.0 % CI 0.987–1.243], Р = 0.083), mean 24-hour diastolic (OR = 1.076 [95.0 % CI 1.017–1.139], Р = 0.011) and pulse blood pressure (OR = 1.075 [95.0 % CІ 1.012–1.141], Р = 0.018), time since hypertension was diagnosed (OR = 1.093 [95.0 % CI 0.997–1.197], Р = 0.057) and office pulse blood pressure (OR = 0.948 [95.0 % CІ 0.900–0.999], Р = 0.046). Conclusions. The study has determined risk factors of developing a prolonged average daily QTc interval in patients with hypertension, which will allow correcting diagnostic and treatment tactics of management for patients from risk groups.

Corrected QT interval in electrocardiogram recordings in patients treated with calcium channel blockers.

One of the most popular tests of the heart is the electrocardiogram (ECG). The physical basis of this study has been known for over 200 years. However, the way an ECG is performed and the interpretation of the obtained results have undergone considerable evolution over time. To analyze the ECG recordings regarding the QTc interval in patients taking calcium channel blockers. The publicly available PhysioNet signals database was used to analyze the effect of selected drugs on the heart rhythm and QTc interval. To automate the QTc assessment, the database was processed in MATLAB. First, QTc was assessed using four formulas; then the results were compared in terms of methodology and medications taken. In the group of patients taking dihydropyridine blockers, the QTc interval assessed by the Bazett formula (mean: 478.87 ms; SD: 73.10) is longer than in patients taking non-dihydropyridine blockers (mean: 446.54 ms, SD: 88.07, p = 0.2123) and in patients not taking calcium channel blockers (mean: 436.33 ms, SD: 49.94, p = 0.0319). The same significant differences were obtained regardless of the QTc assessment method used. However, the QTc result obtained with the Bazett formula is significantly lower than in the case of using the other three formulas used for the presented analysis. Automatic ECG analysis is possible; however, it should be used carefully, considering the possibility of obtaining incorrect results. Taking calcium channel blockers may affect the QTc interval. QTc results significantly depend on the formula based on which we evaluate this parameter.

Effects of Fentanyl Versus Remifentanil Pretreatment on the QTc Interval in Patients Undergoing Rapid Sequence Intubation: A Randomized Clinical Trial.

One of the complications of laryngoscopy is cardiac dysrhythmia due to an increased QT interval. This study aimed to compare the effect of fentanyl and remifentanil on QTc interval in patients undergoing intubation by the rapid method in 2020. In this study, 50 patients without a history of heart disease and without a history of drug use who were candidates for rapid intubation in the emergency department were selected and divided into two groups. Before the injection of intubation drugs, a baseline ECG was obtained from the patient and then randomly assigned to one group of patients with 2 μg/kg fentanyl and the other group with 1 μg/kg remifentanil. Other intubation drugs, including lidocaine, etomidate, and succinylcholine, were fixed in both groups. Immediately after drug injection and immediately after laryngoscopy, ECG was prepared from patients, and the QT interval was calculated. In group comparison, changes in QT values during the studied time were statistically significant (P = 0.004). However, in the comparison between groups, there was no statistically significant difference between the two groups receiving fentanyl and remifentanil (P = 0.235). The results showed that the rate of QT interval changes during three different measurements increased in both groups of patients receiving fentanyl and remifentanil. In the present study, in comparing the QT interval, there was a statistically significant difference between the two groups receiving fentanyl and remifentanil at any of the studied times. Therefore, fentanyl and remifentanil during endotracheal intubation did not have a statistically and clinically significant effect on the QT distance of patients' ECG, and the administration of the above two drugs during intubation was safe.

QTc interval diurnal variations in patients treated with psychotropic medications: implications for the evaluation of drug induced QTc changes

Psychotropic drugs such as antipsychotics may prolong the QTc interval, increasing the risk of torsades de pointes (TdP) and sudden cardiac death. To assess QTc prolongation by psychotropic drugs, an electrocardiogram (EKG) is usually recorded before and after starting treatment. Circadian variations in the QTc interval have been described but have not been adequately studied in patients taking psychotropic drugs. In psychiatric clinical practice, EKGs before and after treatment initiation are often compared, without considering the time of day at which the two EKGs are recorded. To determine whether there is a circadian change in the QTc interval in patients treated with psychotropic drugs, we evaluated the EKGs of a group of patients treated with psychotropic drugs (85% on antipsychotics) and the EKGs of a group of patients that were not treated with medications. In each group, we compared the EKGs recorded before 11:00 am with those recorded after 5:00 pm. The QTc value was significantly longer in the group treated with psychotropic drugs than in the group without drugs at both morning and evening evaluations (p ≤ 0.001). In each group, a statistically significant difference was found between the EKGs recorded before 11:00 a.m. and the EKGs recorded after 5:00 p.m. In patients treated with medications, the mean QTc in the morning was 453.3 ± 25.4 while the mean QTc in the afternoon was 428.4 ± 24.7 (p < 0.0001). In patients who were not receiving any medication, the morning mean QTc was 422.4 ± 22.6 while the mean afternoon QTc was 409.4 ± 19.6 (p = 0.002). These results suggest that a circadian variation in QTc is observed both in patients taking psychotropic drugs and in patients not taking medication. We conclude that any comparison of EKGs to test the effect on QTc of a medication, should be referred to EKGs recorded at the same time of day.

Layer specific strain analysis and QTc interval in patients with STEMI and TIMI 3 early after percutaneous coronary intervention

Abstract Background Heart rate-corrected (QTc) interval may increase in the setting of ST-elevation myocardial infarction (STEMI) even after complete reperfusion of the infarct-related artery. The remaining ischemia affects ventricular repolarization and may be associated with an increased susceptibility for malignant ventricular arrhythmias. Two-dimensional (2D) speckle tracking echocardiography (STE) is an angle-independent technique for evaluating myocardial function. The study aimed to analyze the layers specific strain using STE in patients after percutaneous coronary intervention (PCI) and find a possible correlation with QTc interval. Methods 74 patients with STEMI and TIMI 3 flow after PCI were enrolled. The study did not include patients with bundle branch block, pacing, or treated with drugs that could increase the QTc interval. The evaluation consisted of clinical examination and laboratory tests. 12 leads electrocardiography evaluated QTc interval. Echocardiographic acquisitions were performed in the first 24–48 hours after PCI, and data were analyzed on the workstation. The global longitudinal strain was measured from apical views, at the level of the endocardium GLSAvgEndo, transmural GLSAvg, epicardium GLSAvgEpi; the difference bewtwen endocardium and epicardium longitudinal strain: GLSAvgEndo-GLSAvgEpi. Layer-specific GLS values were measured as the average of the longitudinal strain of 17 LV segments at each individual layer (Figure 1). Results Patients were diveded in two groups: the first included 32 patients with a single vessel disease (43.24%) and the second, 42 patients (56.75%) with multiple vessel damage, but without other indication for revascularization except the culprit lesion. Values for layers strain and QTc interval in the first group were: GLSAvgEndo: −16.2 (SD 2.98, CV 0.18), GLSAvg: −11.46 (SD 6.98, CV 0.6), GLSAvgEndo-GLSAvgEpi: 3.54 (DS 1.06, CV 0.29), QTc: 452.5 (SD 22.65, CV 0.05) and in the second group: GLSAvgEndo: −13.22 (SD 4.01, CV 0.3), GLSAvg: −11.3 (SD 3.39, CV 0.29), GLSAvgEndo-GLSAvgEpi: 3.47 (CV 1.28, CV 0.37), QTc: 490ms (SD 43.07, CV 0.08). QTc interval correlated with and layers strain in the first group: GLSAvgEndo: r=0.56, GLSAvg: r=0.67, GLSendo-GLSepi: r=0.54, and in the second group: GLSAvgEndo: r=0.73, GLSAvg: r=0.75, GLSAvgEndo-GLSAvgEpi: r=0.62. Conclusions 1. The present study identified decreased longitudinal strain in all myocardial layers in the first days after STEMI, even after a successful PCI. 2. Alterations of QTc dynamicity were more frequent in patients with multivessel lesions 3. The electrical instability related by QTc interval correlated with the myocardial tissue damage related by STE. The correlation was more evident in patients with multivessel disease, even with remaining nonsignificant lesions, suggesting an ongoing process of microcirculatory perfusion damage. Funding Acknowledgement Type of funding sources: None.

Fibroblast growth factor 21 is associated with widening QRS complex and prolonged corrected QT interval in patients with stable angina

BackgroundFibroblast growth factor 21 (FGF21) is produced by cardiac cells, may acts in an autocrine manner, and was suggested to has a cardioprotective role in atherosclerosis. Wide QRS complex and heart rate-corrected QT interval (QTc interval) prolongation are associated to dangerous ventricular arrhythmias and cardiovascular disease mortality. Yet, the role of FGF21 in cardiac arrhythmia has never been studied. The aim of the study was to investigate the relationship between plasma FGF21 and the QRS duration and QTc interval in patients with stable angina.MethodsThree hundred twenty-one consecutive stable angina patients were investigated. Plasma FGF21 was measured through ELISA, and each subject underwent 12-lead electrocardiography.ResultsFGF21 plasma levels were positively associated with the QRS duration (β = 0.190, P = 0.001) and QTc interval (β = 0.277, P < 0.0001). With increasing FGF21 tertiles, the patients had higher frequencies of wide QRS complex and prolonged QTc interval. After adjusting for patients’ anthropometric parameters, the corresponding odd ratios (ORs) for wide QRS complex of the medium and high of FGF21 versus the low of FGF21 were 1.39 (95% CI 0.51–3.90) and 4.41 (95% CI 1.84–11.59), respectively, and p for trend was 0.001. Furthermore, multiple logistic regression analysis also showed the corresponding odd ratios (ORs) for prolonged QTc interval of the medium and high of FGF21 versus the low of FGF21 were 1.02 (95% CI 0.53–1.78) and 1.93 (95% CI 1.04–3.60) respectively with the p for trend of 0.037. In addition, age- and sex-adjusted FGF21 levels were positively associated with fasting glucose, HbA1c, creatinine, and adiponectin, but negatively associated with albumin, and the estimated glomerular filtration rate.ConclusionsThis study indicates that plasma FGF21 is associated with wide QRS complex and prolonged corrected QT interval in stable angina patients, further study is required to investigate the role of plasma FGF21 for the underlying pathogenesis.

The long-term efficacy of left cardiac sympathetic denervation in long QT syndrome

Objective: To investigate the long-term efficacy and safety of left cardiac sympathetic denervation(LCSD) for long QT syndrome(LQTS) patients with either recurrence on drug therapy intolerance/refusal. Methods: This study was a retrospective cohort study. The cases selected from 193 patients with LQTS who were enrolled in the Chinese Channelopathy Registry Study from November 1999 to November 2012. This study selected 28 LQTS patients with either recurrence on drug therapy intolerance/refusal and underwent LCSD surgery in the Peking University People's Hospital or Beijing Tongren Hospital. The patients were allocated into 3 groups: high-risk group(n=13, baseline QTc ≥550 ms or symptomatic in the first year of life or highly malignant genetics); intermediate-risk group(n=10, 500 ms≤baseline QTc<550 ms, symptomatic after the first year and without highly malignant genetics); low-risk group(n=5, baseline QTc<500 ms, symptomatic after the first year and without highly malignant genetics). LCSD was performed with the traditional supraclavicular approach or video assisted thoracoscopic surgery (VATS). Patients were regularly followed up until 20 years after the surgery. Data were collected before and 1 year after surgery and at the last follow-up. Patients' electrocardiograph(ECG), cardiac events and surgery-related complications were recorded. Kaplan-Meier survival analysis was used to determine the cardiac event-free survival based on different risk stratification and genotypes. Results: A total of 28 LQTS patients, aged 20.5 (15.0, 37.5) and underwent LCSD surgery, were enrolled in this study, including 23(82.1%) women. There were 11(39.3%) patients treated with traditional approach while 17(60.7%) with VATS-LCSD. There were 19(67.9%) patients had positive genetic test results, including 4 LQT1, 12 LQT2, 1 LQT1/LQT2 mixed type, and 2 Jervell-Lange-Nielsen (JLN) syndrome. The median follow-up period was 189.3(138.7, 204.9) months. The dropout rate was 10.7%(3/28) while 3 patients in the intermediate-risk group were lost to follow-up. Horner syndrome occurred in 1 patient (in the high-risk group). Sudden cardiac deaths were observed in 3 (12.0%) patients (all in the high-risk group), and 12 patients (48.0%) had syncope recurrences (2 in low-risk group, 3 in intermediate-risk group and 7 in high-risk group). A significant reduction in the mean yearly episodes of cardiac events was observed, from (3.5±3.3) before LCSD to(0.2±0.1) at one year after LCSD and (0.5±0.8) at last follow up(P<0.001). The mean QTc was shortened from (545.7±51.2)ms before the surgery to (489.0±40.1)ms at the last follow-up (P<0.001). Among the 20 patients with basic QTc ≥500 ms and completing the follow-up, the QTc intervals of 11(55.0%) patients were shortened to below 500 ms. The event free survival rates for any cardiac events after LCSD decreased sequentially in the low-, intermediate- and high-risk groups, and the difference was statistically significant (χ²=7.24, log-rank P=0.026). No difference was found in the event free survival rates among LQT1, LQT2 and undefined gene patients (χ²=5.20, log-rank P>0.05). Conclusions: LCSD surgery can reduce the incidence of cardiac events and shorten the QTc interval in patients with LQTS after the long-term follow-up. LCSD surgery is effective and safe for patients with LQTS ineffective or intolerant to drug therapy. However, high-risk patients are still at a high risk of sudden death after surgery and should be actively monitored and protected by combined therapies.

C-reactive Protein Elevation Is Associated With QTc Interval Prolongation in Patients Hospitalized With COVID-19.

BackgroundThe relationship between inflammation and corrected QT (QTc) interval prolongation is currently not well defined in patients with COVID-19.ObjectiveThis study aimed to assess the effect of marked interval changes in the inflammatory marker C-reactive protein (CRP) on QTc interval in patients hospitalized with COVID-19.MethodsIn this retrospective cohort study of hospitalized adult patients admitted with COVID-19 infection, we identified 85 patients who had markedly elevated CRP levels and serial measurements of an ECG and CRP during the same admission. We compared mean QTc interval duration, and other clinical and ECG characteristics between times when CRP values were high and low. We performed mixed-effects linear regression analysis to identify associations between CRP levels and QTc interval in univariable and adjusted models.ResultsMean age was 58 ± 16 years, of which 39% were women, 41% were Black, and 25% were White. On average, the QTc interval calculated via the Bazett formula was 15 ms higher when the CRP values were “high” vs. “low” [447 ms (IQR 427–472 ms) and 432 ms (IQR 412–452 ms), respectively]. A 100 mg/L increase in CRP was associated with a 1.5 ms increase in QTc interval [β coefficient 0.15, 95% CI (0.06–0.24). In a fully adjusted model for sociodemographic, ECG, and clinical factors, the association remained significant (β coefficient 0.14, 95% CI 0.05–0.23).ConclusionAn interval QTc interval prolongation is observed with a marked elevation in CRP levels in patients with COVID-19.

QTc Prolongation with the Use of Hydroxychloroquine and Concomitant Arrhythmogenic Medications: A Retrospective Study Using Electronic Health Records Data.

IntroductionHydroxychloroquine can induce QT/QTc interval prolongation for some patients; however, little is known about its interactions with other QT-prolonging drugs.ObjectiveThe purpose of this retrospective electronic health records study was to evaluate changes in the QTc interval in patients taking hydroxychloroquine with or without concomitant QT-prolonging medications.MethodsDe-identified health records were obtained from the Cerner Health Facts® database. Variables of interest included demographics, diagnoses, clinical procedures, laboratory tests, and medications. Patients were categorized into six cohorts based on exposure to hydroxychloroquine, methotrexate, or sulfasalazine alone, or the combination of any those drugs with any concomitant drug known to prolong the QT interval. Tisdale QTc risk score was calculated for each patient cohort. Two-sample paired t-tests were used to test differences between the mean before and after QTc measurements within each group and ANOVA was used to test for significant differences across the cohort means.ResultsA statistically significant increase in QTc interval from the last measurement prior to concomitant exposure of 18.0 ms (95% CI 3.5–32.5; p < 0.05) was found in the hydroxychloroquine monotherapy cohort. QTc changes varied considerably across cohorts, with standard deviations ranging from 40.9 (hydroxychloroquine monotherapy) to 57.8 (hydroxychloroquine + sulfasalazine). There was no difference in QTc measurements among cohorts. The hydroxychloroquine + QTc-prolonging agent cohort had the highest average Tisdale Risk Score compared with those without concomitant exposure (p < 0.05).ConclusionOur analysis of retrospective electronic health records found hydroxychloroquine to be associated with a moderate increase in the QTc interval compared with sulfasalazine or methotrexate. However, the QTc was not significantly increased with concomitant exposure to other drugs known to increase QTc interval.

Heart-Rate-Corrected QT Interval Response to Ramosetron during Robot-Assisted Laparoscopic Prostatectomy: A Randomized Trial.

Ramosetron, often used to prevent postoperative nausea and vomiting, might cause heart-rate-corrected (QTc) interval prolongation, as might robot-assisted laparoscopic prostatectomy (RALP), which requires a steep Trendelenburg position and CO2 pneumoperitoneum. This study aimed to determine how ramosetron administration affects the QTc interval in patients treated with RALP. Fifty-six subjects were randomly assigned to ramosetron (n = 28) or control (n = 28) groups. The ramosetron group received 0.3 mg of ramosetron after anesthetic induction, whereas the control group received normal saline. The QTc interval was measured before and after induction; after 5, 30, and 60 min of being placed in the Trendelenburg position; immediately after being returned to a supine position; and at the end of surgery. Linear mixed models were used to compare QT intervals between groups. QTc intervals did not differ significantly between groups over time (Pgroup×time = 0.111). However, they increased significantly in both groups after placement in the Trendelenburg position compared with before induction (Ptime < 0.001). This increase in QTc continued until the end of surgery in both groups. Based on these findings, ramosetron can be safely administered for the prevention of postoperative nausea and vomiting among patients undergoing RALP.

QTc interval prolongation due to spinal anesthesia in patients with and without diabetes: an observational study

BackgroundSpinal anesthesia and autonomic neuropathy (caused by diabetes) prolong the QTc interval. Changes in the duration of the QTc interval following subarachnoid blockade in patients with diabetes have not been evaluated. We hypothesized that after subarachnoid blockade, QTc interval prolongation would be greater in patients with diabetes than in those without. Accordingly, we compared the QTc interval, T wave peak-to-end interval (Tp-e interval), blood pressure, heart rate, and heart rate variability before and after spinal anesthesia in patients with and without diabetes.MethodsThis prospective observational study (Clinical Research Information Service identifier: KCT0004897) was conducted in a tertiary university hospital and included 24 patients with diabetes mellitus (DM group) and 24 patients without it (control group) who were scheduled for spinal anesthesia. The QTc interval, Tp-e interval, heart rate variability, blood pressure, and heart rate were measured before (T1) and 1 (T2), 5 (T3), and 10 min (T4) following subarachnoid blockade.ResultsTen minutes following subarachnoid blockade, the QTc intervals of patients in the DM group were significantly longer than the baseline values, whereas the change in the QTc interval in the control group was not significant (p < 0.0001 vs. p = 0.06).ConclusionSpinal anesthesia caused a more significant prolongation of the QTc interval in patients with diabetes than in those without.

QTc interval in patients with pheochromocytoma and paraganglioma

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