Assessment of drug-induced torsade de pointes risk for hospitalized high-risk patients receiving QT-prolonging agents

Corrected QT Interval (QTc) Diagnostic App for the Oncological Routine: Development Study

BACKGROUND

Numerous antineoplastic drugs such as chemotherapeutics have cardiotoxic side effects and can lead to long QT syndrome (LQTS). When diagnosed and treated in time, the potentially fatal outcomes of LQTS can be prevented. Therefore, regular electrocardiogram (ECG) assessments are critical to ensure patient safety. However, these assessments are associated with patient discomfort and require timely support of the attending oncologist by a cardiologist.

OBJECTIVE

This study aimed to examine whether this approach can be made more efficient and comfortable by a smartphone app (QTc Tracker), supporting single-lead ECG records on site and transferring to a tele-cardiologist for an immediate diagnosis.

METHODS

To evaluate the QTc Tracker, it was implemented in 54 cancer centers in Germany. In total, 266 corrected QT interval (QTc) diagnoses of 122 patients were recorded. Moreover, a questionnaire on routine ECG workflow, turnaround time, and satisfaction (1=best, 6=worst) was answered by the centers before and after the implementation of the QTc Tracker.

RESULTS

Compared to the routine ECG workflow, the QTc Tracker enabled a substantial turnaround time reduction of 98% (mean 2.67, 95% CI 1.72-2.67 h) and even further time efficiency in combination with a cardiologic on-call service (mean 12.10, 95% CI 5.67-18.67 min). Additionally, nurses and patients reported higher satisfaction when using the QTc Tracker. In particular, patients' satisfaction sharply improved from 2.59 (95% CI 2.41-2.88) for the routine ECG workflow to 1.25 (95% CI 0.99-1.51) for the QTc Tracker workflow.

CONCLUSIONS

These results reveal a significant improvement regarding reduced turnaround time and increased user satisfaction. Best patient care might be guaranteed as the exposure of patients with an uncontrolled risk of QTc prolongations can be avoided by using the fast and easy QTc Tracker. In particular, as regular side-effect monitoring, the QTc Tracker app promises more convenience for patients and their physicians. Finally, future studies are needed to empirically test the usability and validity of such mobile ECG assessment methods.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04055493; https://classic.clinicaltrials.gov/ct2/show/NCT04055493.

Use of Electrocardiogram Monitoring in Adult Patients Taking High-Risk QT Interval Prolonging Medicines in Clinical Practice: Systematic Review and Meta-analysis

Introduction

Electrocardiogram (ECG) monitoring is an important tool to detect and mitigate the risk of potentially fatal drug-induced QT prolongation and remains fundamental in supporting the quality use of high-risk QT interval prolonging medicines.

Objective

The aim of this systematic review was to determine the prevalence of baseline and/or follow-up ECG use in adult patients taking high-risk QT interval prolonging medicines in clinical practice.

Methods

CINAHL, Cochrane Library, Embase, PubMed, EThOS, OpenGrey and Proquest were searched for studies in adults that reported ECG use at baseline and/or at follow-up in relation to the initiation of a high-risk QT interval prolonging medicine in any clinical setting; either hospital or non-hospital. Two reviewers independently assessed the methodological quality of included studies. Proportional meta-analysis was conducted with all studies reporting baseline ECG use, before medicine initiation, and follow-up ECG use, within 30 days of medicine initiation.

Results

There was variability in baseline ECG use according to the practice setting. The prevalence of baseline ECG use for high-risk QT interval prolonging medicines was moderate to high in the hospital setting at 75.1% (95% CI 64.3–84.5); however, the prevalence of baseline ECG use was low in the non-hospital setting at 33.7% (95% CI 25.8–42.2). The prevalence of follow-up ECG use was low to moderate in the hospital setting at 39.2% (95% CI 28.2–50.8) and could not be determined for the non-hospital setting.

Conclusions

The use of ECG monitoring for high-risk QT interval prolonging medicines is strongly influenced by the clinical practice setting. Baseline ECG use occurs more in the hospital setting in comparison to the non-hospital setting. There is lower use of follow-up ECG in comparison to baseline ECG.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40264-022-01215-x.

Use of ECG monitoring for adult patients taking high-risk QT interval-prolonging drugs in clinical practice: a systematic review protocol

OBJECTIVE

The objective of this review is to determine the rates of electrocardiogram use in adult patients taking high-risk QT interval-prolonging drugs in clinical settings. This review will determine the extent of ECG monitoring being used to mitigate the risk of drug-induced QT prolongation.

INTRODUCTION

High-risk QT interval-prolonging drugs pose a well-established risk of cardiac arrhythmia, including torsades de pointes, among other serious long QT syndromes, which can be fatal. Detection and mitigation of QT prolongation involves use of electrocardiogram monitoring. This systematic review will present evidence for uptake of electrocardiogram monitoring in clinical practice to support the quality use of high-risk QT interval-prolonging drugs.

INCLUSION CRITERIA

Quantitative studies, published from 2004 that determine the rate of electrocardiogram monitoring before and during use of high-risk QT interval-prolonging drugs in adults 18 years or older, either in community or hospital settings, will be eligible for inclusion.

METHODS

CINAHL, Cochrane Library, Embase, and PubMed will be searched to identify published studies. EThOS, OpenGrey, and ProQuest Dissertations and Theses will be searched to identify unpublished studies. Conference abstracts will be excluded. There will be no restriction on country or language. Two reviewers will independently screen and select studies, assess methodological quality, and extract data. The JBI approach to systematic reviews of prevalence and incidence will be followed. Meta-analysis will be performed, if possible, and the Grading of Recommendations Assessment Development and Evaluation (GRADE) Summary of Findings presented.

Detecting drug-drug interactions that increase the incidence of long QT syndrome using a spontaneous reporting system

WHAT IS KNOWN AND OBJECTIVE

Drug-induced long QT syndrome (diLQTS) is a rare but serious adverse drug reaction. Drug-drug interaction (DDI) is one of the risk factors for the development of diLQTS. However, the combinations of drugs that increase the risk of diLQTS have not been extensively investigated. This study was performed to analyse the potential DDIs that elevate the incidence of diLQTS using a spontaneous reporting system.

METHODS

The Japanese Adverse Drug Event Report database from April 2004 to January 2020 was used to assess adverse event reports. We calculated the reporting odds ratio and 95% confidence interval for signal detection.

RESULTS AND DISCUSSION

Signals for concomitant use risk were detected in 31 drug combinations. Combinations of antipsychotics and antidepressants were the most common (olanzapine & fluvoxamine, olanzapine & trazodone, quetiapine & paroxetine, sulpiride & fluvoxamine, sulpiride & trazodone). Sixteen, 17 and 21 combinations were designated as requiring precaution for concomitant use in at least one of the package inserts in Japan, the United States and the United Kingdom, respectively, although no such precautions were described for the remaining combinations. On the contrary, a combination of bepridil & clarithromycin was categorized as "X (avoid combination)" and two combinations (chlorpromazine & haloperidol, amiodarone & metildigoxin) were classified as "D (modify regimen)" in the Lexicomp^® risk rating.

WHAT IS NEW AND CONCLUSION

This study identified 31 combinations of drugs that may elevate the risk of diLQTS. The use of these drug combinations should be monitored more carefully in future.

Drug-Induced QTc Prolongation: What We Know and Where We Are Going

Drug-induced QTc prolongation is a concerning electrocardiogram (ECG) abnormality. This cardiac disturbance carries a 10% risk of sudden cardiac death due to the malignant arrhythmia, Torsades de Pointes. The Arizona Center for Education and Research on Therapeutics (AzCERT) has classified QTc prolonging therapeutic classes such as antiarrhythmics, antipsychotics, anti-infectives, and others. AzCERT criteria categorizes medications into three risk categories: "known," "possible," and "conditional risk" of QTc prolongation and Torsades de Pointes. The list of QTc prolonging medications continues to expand as new drug classes are approved and studied. Risk factors for QTc prolongation can be delineated into modifiable or non-modifiable. A validated risk scoring tool may be utilized to predict the likelihood of prolongation in patients receiving AzCERT classified medication. The resultant risk score may be applied to a clinical decision support system which offers mitigation strategies. Mitigation strategies including discontinuation of possible offending agents with selection of an alternative agent, assessment of potential drug interactions or dose adjustments through pharmacokinetic and pharmacodynamic monitoring, and initiation of both ECG and electrolyte monitoring are essential to prevent a drug-induced arrhythmia. The challenges presented by the COVID-19 pandemic have led to the development of innovative continuous monitoring technology, increasing protection for both patients and healthcare workers. Early intervention strategies may reduce adverse events and improve clinical outcomes in patients identified to be at risk of QTc prolongation.

Impact of Medical Castration on Malignant Arrhythmias in Patients With Prostate Cancer

Background

Medical castration, gonadotropin‐releasing hormone agonists, and antiandrogens have been widely applied as a treatment for prostate cancer. Sex steroid hormones influence cardiac ion channels. However, few studies have examined the proarrhythmic properties of medical castration.

Methods and Results

This study included 149 patients who underwent medical castration using gonadotropin‐releasing hormones with/without antiandrogen for prostate cancer. The changes in the ECG findings during the therapy and associations of the electrocardiographic findings with malignant arrhythmias were studied. The QT and corrected QT (QTc) intervals prolonged during the therapy compared with baseline (QT, 394±32 to 406±39 ms [P<0.001]; QTc, 416±27 to 439±31 ms [P<0.001]). The QTc interval was prolonged in 119 (79.9%) patients during the therapy compared with baseline. In 2 (1.3%) patients who had no structural heart disease, torsade de pointes (TdP) and ventricular fibrillation (VF) occurred ≥6 months after starting the therapy. In patients with TdP/VF, the increase in the QTc interval from the pretreatment value was >80 ms. However, in patients without TdP/VF, the prevalence of an increase in the QTc interval from the pretreatment value of >50 ms was 11%, and an increase in the QTc interval from the pretreatment value >80 ms was found in only 4 (3%) patients.

Conclusions

Medical castration prolongs the QT/QTc intervals in most patients with prostate cancer, and it could cause TdP/VFs even in patients with no risk of QT prolongation before the therapy. An increase in the QTc interval from the pretreatment value >50 ms might become a predictor of TdP/VF. Much attention should be paid to the QTc interval throughout all periods of medical castration to prevent malignant arrhythmias.

Comparative risk of cardiac arrhythmias associated with acetylcholinesterase inhibitors used in treatment of dementias - A narrative review

Donepezil, galantamine, and rivastigmine are the three acetylcholinesterase inhibitors (AChEIs), out of a total of only four medications prescribed in the treatment of Alzheimer's Disease (AD) and related dementias. These medications are known to be associated with bradycardia given their mechanism of action of increasing acetylcholine (ACh). However, in March 2015, donepezil was added to the CredibleMeds "known-risk" category, a list where medications have a documented risk for acquired long-QT syndrome (ALQTS) and torsades de pointes (TdP) - a malignant ventricular arrhythmia that is a different adverse event than bradycardia (and is not necessarily associated with ACh action). The purpose of this article is to review the three AChEIs, especially with regards to mechanistic differences that may explain why only donepezil poses this risk; several pharmacological mechanisms may explain why. However, from an empirical point-of-view, aside from some case-reports, only a limited number of studies have generated relevant information regarding AChEIs' and electrocardiogram findings; none have specifically compared donepezil against galantamine or rivastigmine for malignant arrhythmias such as TdP. Currently, the choice of one of the three AChEIs for treatment of AD symptoms is primarily dependent upon clinician and patient preference. However, clinicians should be aware of the potential increased risk associated with donepezil. There is a need to examine the comparative risk of malignant arrhythmias among AChEIs users in real-world practice; this may have important implications with regards to changes in AChEI prescribing patterns.

Development and validation of a tool to assess the risk of QT drug-drug interactions in clinical practice

BACKGROUND

The exact risk of developing QTc-prolongation when using a combination of QTc-prolonging drugs is still unknown, making it difficult to interpret these QT drug-drug interactions (QT-DDIs). A tool to identify high-risk patients is needed to support healthcare providers in handling automatically generated alerts in clinical practice. The main aim of this study was to develop and validate a tool to assess the risk of QT-DDIs in clinical practice.

METHODS

A model was developed based on risk factors associated with QTc-prolongation determined in a prospective study on QT-DDIs in a university medical center inthe Netherlands. The main outcome measure was QTc-prolongation defined as a QTc interval > 450 ms for males and > 470 ms for females. Risk points were assigned to risk factors based on their odds ratios. Additional risk factors were added based on a literature review. The ability of the model to predict QTc-prolongation was validated in an independent dataset obtained from a general teaching hospital against QTc-prolongation as measured by an ECG as the gold standard. Sensitivities, specificities, false omission rates, accuracy and Youden's index were calculated.

RESULTS

The model included age, gender, cardiac comorbidities, hypertension, diabetes mellitus, renal function, potassium levels, loop diuretics, and QTc-prolonging drugs as risk factors. Application of the model to the independent dataset resulted in an area under the ROC-curve of 0.54 (95% CI 0.51-0.56) when QTc-prolongation was defined as > 450/470 ms, and 0.59 (0.54-0.63) when QTc-prolongation was defined as > 500 ms. A cut-off value of 6 led to a sensitivity of 76.6 and 83.9% and a specificity of 28.5 and 27.5% respectively.

CONCLUSIONS

A clinical decision support tool with fair performance characteristics was developed. Optimization of this tool may aid in assessing the risk associated with QT-DDIs.

TRIAL REGISTRATION

No trial registration, MEC-2015-368.

A literature-based algorithm for the assessment, management, and monitoring of drug-induced QTc prolongation in the psychiatric population

BACKGROUND

Certain psychotropics and a number of other medications used to treat medical conditions in psychiatric patients can increase the risk of prolonging the corrected QT (QTc) interval on the electrocardiogram, which puts patients at risk of life-threatening ventricular arrhythmias such as torsades de pointes. Pharmacists are often consulted about medications which are known to prolong the QTc interval. Although this information is often accessible, advising how to identify, assess, manage, and refer psychiatric patients at risk for drug-induced QTc prolongation is more challenging.

OBJECTIVES

The objective of this project was first to review the literature, which describes guidelines and recommendations for the assessment and management of drug-induced QTc prolongation, and then to design an algorithm to be used by pharmacists working closely with mental health professionals or who provide care to psychiatric patients.

METHODS

A review of the literature was undertaken. Predefined keywords were used to perform the database search in MEDLINE, EMBASE, and International Pharmaceutical Abstracts to identify reviews, reports and guidelines on the assessment, prevention and monitoring of drug-induced QTc prolongation with an emphasis on psychotropic medications and management in the psychiatric population.

RESULTS

The electronic database search retrieved 637 relevant citations. These were initially screened by title and all duplicates were removed. The abstracts were then reviewed for relevancy based on the inclusion/exclusion criteria. Additional citations were retrieved from the bibliography of the articles identified in the initial search. A total of 79 articles describing QTc prolongation in the psychiatric population were thoroughly examined, but only 31 articles were selected to guide the development of the algorithm.

CONCLUSION

The literature-based algorithm developed provides a stepped-based approach for the assessment, monitoring, and management of drug-induced QTc prolongation in the psychiatric population. The algorithm may assist mental health clinicians in the decision-making process when psychiatric patients are prescribed medications known to increase the QTc interval.

Limited Evidence for Risk Factors for Proarrhythmia and Sudden Cardiac Death in Patients Using Antidepressants: Dutch Consensus on ECG Monitoring

Currently, there is a lack of international and national guidelines or consensus documents with specific recommendations for electrocardiogram (ECG) screening and monitoring during antidepressant treatment. To make a proper estimation of the risk of cardiac arrhythmias and sudden (cardiac) death during antidepressant use, both the drug and patient-specific factors should be taken into account; however, solid evidence on how this should be done in clinical practice is lacking. Available recommendations on the management of QT(c) prolongation (with antidepressant treatment) emphasize that special attention should be given to high-risk patients; however, clinicians are in need of more concrete suggestions about how to select patients for ECG screening and monitoring. Based on a review of the literature, a Dutch multidisciplinary expert panel aimed to formulate specific guidelines to identify patients at risk for cardiac arrhythmias and sudden death by developing a consensus statement regarding ECG screening before, and monitoring during, antidepressant use. We first reviewed the literature to identify the relative risks of various risk factors on cardiac arrhythmia and sudden (cardiac) death during antidepressant use. These relative contributions of risk factors could not be determined since no systematic reviews or meta-analyses quantitatively addressed this topic. Because evidence was insufficient, additional expert opinion was used to formulate recommendations. This resulted in readily applicable recommendations for clinical practice for selection of high-risk patients for ECG screening and monitoring. ECG screening and monitoring is recommended before and following the start of QTc-prolonging antidepressants in the presence of vulnerability to QTc prolongation or two or more risk factors (age > 65 years, female sex, concomitant use of a QTc-prolonging drug or concomitant use of a drug that influences the metabolism of a QTc-prolonging drug, cardiac disease, excessive dosing and specific electrolyte disturbances).

Development of a risk model for predicting QTc interval prolongation in patients using QTc-prolonging drugs

Background Numerous drugs prolong the QTc interval on the ECG and potentially increase the risk of cardiac arrhythmia. This risk is clinically relevant in patients with additional risk factors. Objective The objective was to develop and validate a risk model to predict QTc interval prolongation of eligible ECGs. Setting Spaarne Gasthuis (Haarlem/Hoofddorp, The Netherlands). Method A dataset was created from ECGs recorded in patients using one or more QTc prolonging drugs, in the period January 2013 and October 2016. In the development set, independent risk factors for QTc interval prolongation were determined using binary logistic regression. Risk scores were assigned based on the beta coefficient. In the risk-score validation set, the area under the ROC-curve, sensitivity and specificity were calculated. Main outcome measure QTc interval prolongation, defined as a QTc interval > 500 ms. Results In the development set 12,949 ECGs were included and in the risk-score validation set 6391 ECGs. The proportion of ECGs with a prolonged QTc interval in patients with no risk factors in the risk-score validation set was 2.7%, while in patients with a high risk score the proportion was 26.1%. The area under the ROC curve was 0.71 (95% CI 0.68-0.73). The sensitivity and specificity were 0.81 and 0.48, respectively. Conclusion A risk model was developed and validated for the prediction of QTc interval prolongation. This risk model can be implemented in a clinical decision support system, supporting the management of the risks involved with QTc interval prolonging drugs.

Risk factors for QTc interval prolongation

PURPOSE

Prolongation of the QTc interval may result in Torsade de Pointes, a ventricular arrhythmia. Numerous risk factors for QTc interval prolongation have been described, including the use of certain drugs. In clinical practice, there is much debate about the management of the risks involved. In this study, we quantified the effect of these risk factors on the length of the QTc interval.

METHODS

We analyzed all ECGs that were taken during routine practice between January 2013 and October 2016 in the Spaarne Gasthuis, a general teaching hospital in the Netherlands. We collected laboratory values in the week before the ECG recording and the drugs prescribed. For the identification of risk factors, we used multilevel linear regression analysis to correct for multiple ECG recordings per patient.

RESULTS

We included 133,359 ECGs in our study, taken in 40,037 patients. Patients using one QT-prolonging drug had a 11.08 ms (95% CI 10.63-11.52; p < 0.001) longer QTc interval. Patients using two QT-prolonging drugs had a 3.04 ms (95% CI 2.06-4.02; p < 0.001) increase in the QTc interval compared to patients using one QT-prolonging drug. Women had a longer QTc interval compared to men (16.30 ms 95% CI 14.59-18.01; p < 0.001). The QTc interval increased with increasing age, but the difference between men and women diminished. Other independent risk factors that significantly prolonged the QTc interval with at least 10 ms were hypokalemia, hypocalcemia, and the use of loop diuretics.

CONCLUSION

We identified and quantified various risk factors for QTc interval prolongation.

Risk factors for QTc-prolongation: systematic review of the evidence

Background QTc-interval prolongation has been associated with serious adverse events, such as Torsade de Pointes and sudden cardiac death. In the prevention of QTc-prolongation, special attention should go to high-risk patients. Aim of the review The aim of this review is to summarize and assess the evidence for different risk factors for QTc-prolongation (demographic factors, comorbidities, electrolytes, QTc-prolonging medication). Methods Potential studies were retrieved based on a systematic search of articles published until June 2015 in the databases Medline and Embase. Both terms about QTc-prolongation/Torsade de Pointes and risk factors were added in the search strategy. The following inclusion criteria were applied: randomized controlled trials and observational studies; inclusion of ≥500 patients from a general population (not limited to specific disease states); assessment of association between QTc-interval and risk factors. For the articles that met the inclusion criteria, the following data were extracted: study design, setting and study population, number of patients and cases of QTc-prolongation, method of electrocardiogram-monitoring, QTc-correction formula, definition of QTc-prolongation, statistical methods and results. Quality assessment was performed using the GRADE approach (for randomized controlled trials) and the STROBE-recommendations (for observational studies). Based on the number of significant results and the level of significance, a quotation of the evidence was allocated. Results Ten observational studies could be included, with a total of 89,532 patients [prospective cohort design: N = 6; multiple regression analyses: N = 5; median STROBE score = 17/22 (range 15-18)]. Very strong evidence was found for hypokalemia, use of diuretics, antiarrhythmic drugs and QTc-prolonging drugs of list 1 of CredibleMeds. Little or no evidence was found for hyperlipidemia, the use of digoxin or statins, neurological disorders, diabetes, renal failure, depression, alcohol abuse, heart rate, pulmonary disorders, hormone replacement therapy, hypomagnesemia, history of a prolonged QTc-interval/Torsade de Pointes, familial history of cardiovascular disease, and the use of only QTc-prolonging drugs of list 2 or 3 of CredibleMeds. Conclusion This systematic review gives a clear overview of the available evidence for a broad range of risk factors for QTc-prolongation.

Co-Prescription of QT-Interval Prolonging Drugs: An Analysis in a Large Cohort of Geriatric Patients

BACKGROUND

Drug-induced QT-interval prolongation is associated with occurrence of potentially fatal Torsades de Pointes arrhythmias (TdP). So far, data regarding the overall burden of QT-interval prolonging drugs (QT-drugs) in geriatric patients are limited.

OBJECTIVE

This study was performed to assess the individual burden of QT-interval prolonging drugs (QT-drugs) in geriatric polymedicated patients and to identify the most frequent and risky combinations of QT-drugs.

METHODS

In the discharge medication of geriatric patients between July 2009 and June 2013 from the Geriatrics in Bavaria-Database (GiB-DAT) (co)-prescriptions of QT-drugs were investigated. QT-drugs were classified according to a publicly available reference site (CredibleMeds®) as ALL-QT-drugs (associated with any QT-risk) or High-risk-QT-drugs (corresponding to QT-drugs with known risk of Torsades de Pointes according to CredibleMeds®) and in addition as SmPC-high-risk-QT-drugs (according to the German prescribing information (SmPC) contraindicated co-prescription with other QT-drugs).

RESULTS

Of a cohort of 130,434 geriatric patients (mean age 81 years, 67% women), prescribed a median of 8 drugs, 76,594 patients (58.7%) received at least one ALL-QT-drug. Co-prescriptions of two or more ALL-QT-drugs were observed in 28,768 (22.1%) patients. Particularly risky co-prescriptions of High-risk-QT-drugs or SmPC-high-risk-QT-drugs with at least on further QT-drug occurred in 55.9% (N = 12,633) and 54.2% (N = 12,429) of these patients, respectively. Consideration of SmPCs (SmPC-high-risk-QT-drugs) allowed the identification of an additional 15% (N = 3,999) patients taking a risky combination that was not covered by the commonly used CredibleMeds® classification. Only 20 drug-drug combinations accounted for more than 90% of these potentially most dangerous co-prescriptions.

CONCLUSION

In a geriatric study population co-prescriptions of two and more QT-drugs were common. A considerable proportion of QT-drugs with higher risk only could be detected by using more than one classification-system. Local adaption of international classifications can improve identification of patients at risk.

Ventricular repolarization measures for arrhythmic risk stratification

Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave (QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice.

Ventricular repolarization measures for arrhythmic risk stratification

Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave (QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice.