Conventional and new electrocardiographic criteria for hypertension-mediated cardiac organ damage: A narrative review.

Hypertension-mediated organ damage (HMOD) is frequently observed in hypertensive patients at different cardiovascular (CV) risk profile. This may have both diagnostic and therapeutic implications for the choice of the most appropriate therapies. Among different markers of HMOD, the most frequent functional and structural adaptations can be observed at cardiac level, including left ventricular hypertrophy (LVH), diastolic dysfunction, aortic root dilatation, and left atrial enlargement. In particular, LVH was shown to be a strong and independent risk factor for major CV events, namely myocardial infarction, stroke, congestive heart failure, CV death. Thus, early identification of LVH is a key element for preventing CV events in hypertension. Although echocardiographic assessment of LVH represents the gold standard technique, this is not cost-effective and cannot be adopted in routine clinical practice of hypertension. On the other hand, electrocardiographic (ECG) assessment of HMOD relative to the heart is a simple, reproducible, widely available and cost-effective method to assess the presence of LVH, and could be preferred in large scale screening tests. Several new indicators have been proposed and tested in observational studies and clinical trials of hypertension, in order to improve the relatively low sensitivity of the conventional ECG criteria for LVH, despite high specificity. This article reviews the differences in the use of the main conventional and the new 12 lead ECG criteria of LVH for early assessment of asymptomatic, subclinical cardiac HMOD in a setting of clinical practice of hypertension.

Pitfalls of assessment of autonomic function by heart rate variability.

Although analysis of heart rate variability is widely used for the assessment of autonomic function, its fundamental framework linking low-frequency and high-frequency components of heart rate variability with sympathetic and parasympathetic autonomic divisions has developed in the 1980s. This simplified framework is no longer able to deal with much evidence about heart rate variability accumulated over the past half-century. This review addresses the pitfalls caused by the old framework and discusses the points that need attention in autonomic assessment by heart rate variability.

How well is each learner learning? Validity investigation of a learning curve-based assessment approach for ECG interpretation.

Learning curves can support a competency-based approach to assessment for learning. When interpreting repeated assessment data displayed as learning curves, a key assessment question is: "How well is each learner learning?" We outline the validity argument and investigation relevant to this question, for a computer-based repeated assessment of competence in electrocardiogram (ECG) interpretation. We developed an on-line ECG learning program based on 292 anonymized ECGs collected from an electronic patient database. After diagnosing each ECG, participants received feedback including the computer interpretation, cardiologist's annotation, and correct diagnosis. In 2015, participants from a single institution, across a range of ECG skill levels, diagnosed at least 60 ECGs. We planned, collected and evaluated validity evidence under each inference of Kane's validity framework. For Scoring, three cardiologists' kappa for agreement on correct diagnosis was 0.92. There was a range of ECG difficulty across and within each diagnostic category. For Generalization, appropriate sampling was reflected in the inclusion of a typical clinical base rate of 39% normal ECGs. Applying generalizability theory presented unique challenges. Under the Extrapolation inference, group learning curves demonstrated expert-novice differences, performance increased with practice and the incremental phase of the learning curve reflected ongoing, effortful learning. A minority of learners had atypical learning curves. We did not collect Implications evidence. Our results support a preliminary validity argument for a learning curve assessment approach for repeated ECG interpretation with deliberate and mixed practice. This approach holds promise for providing educators and researchers, in collaboration with their learners, with deeper insights into how well each learner is learning.

Assessment of Novel Peguero-Lo Presti Electrocardiographic Left Ventricular Hypertrophy Criteria in a Large Asian Population: Newer May Not Be Better.

BACKGROUND: Recently, the novel Peguero-Lo Presti electrocardiographic criteria to diagnose left ventricular hypertrophy (LVH) were developed from Caucasian American population with a relatively high sensitivity. However, further validation on a large Asian population has never been conducted. Thus, this study was to test and validate the overall performance of this index in a general population from China. METHODS: A total of 10,614 permanent residents ≥35 years of age were included in this study. All participants completed 12-lead electrocardiography and echocardiography at the same visit. A receiver-operating characteristic curve was used for comparing the performance of electrocardiographic indices in diagnosing echocardiographic LVH. RESULTS: The Peguero-Lo Presti criteria had higher sensitivity but lower specificity than Cornell and Sokolow-Lyon voltage according to the recommended criteria. The area under the curve of this novel Peguero-Lo Presti voltage was lower than that of Cornell for predicting LVH defined by both left ventricular mass/body surface area (0.665 vs 0.699 in males; 0.689 vs 0.721 in females) and left ventricular mass/height2.7 (0.623 vs 0.681 in males; 0.642 vs 0.709 in females) (all Ps < 0.05). By changing cutoff values, Cornell voltage outperformed Peguero-Lo Presti whether to achieve a relatively high sensitivity or specificity. CONCLUSIONS: The novel Peguero-Lo Presti voltage may not be a better screening tool for LVH in Asian population. In comparison with this new index, Cornell voltage could be a better screening test for LVH by changing its cutoff values to obtain maximum sensitivity.

Can We Improve Physical Health Monitoring for Patients Taking Antipsychotics on a Mental Health Inpatient Unit?

BACKGROUND: Patients with severe mental illness are at risk of medical complications, including cardiovascular disease, metabolic syndrome, and diabetes. Given this vulnerability, combined with metabolic risks of antipsychotics, physical health monitoring is critical. Inpatient admission is an opportunity to screen for medical comorbidities. Our objective was to improve the rates of physical health monitoring on an inpatient psychiatry unit through implementation of an electronic standardized order set. METHODS: Using a clinical audit tool, we completed a baseline retrospective audit (96 eligible charts) of patients aged 18 to 100 years, discharged between January and March 2012, prescribed an antipsychotic for 3 or more days. We then developed and implemented a standard electronic admission order set and provided training to inpatient clinical staff. We completed a second chart audit of patients discharged between January and March 2016 (190 eligible charts) to measure improvement in physical health monitoring and intervention rates for abnormal results. RESULTS: In the 2012 audit, thyroid-stimulating hormone (TSH), blood pressure, blood glucose, fasting lipids, electrocardiogram (ECG), and height/weight were measured in 71%, 92%, 31%, 36%, 51%, and 75% of patients, respectively. In the 2016 audit, TSH, blood pressure, blood glucose, fasting lipids, ECG, and height/weight were measured in 86%, 96%, 96%, 64%, 87%, and 71% of patients, respectively. There were statistically significant improvements (P < 0.05) in monitoring rates for blood glucose, lipids, ECG, and TSH. Intervention rates for abnormal blood glucose and/or lipids (feedback to family doctor and/or patient, consultation to hospitalist, endocrinology, and/or dietician) did not change between 2012 and 2016. CONCLUSIONS: Electronic standardized order set can be used as a tool to improve screening for physical health comorbidity in patients with severe mental illness receiving antipsychotic medications.

Benchmarking Heart Rate Variability to Overcome Sex-Related Bias.

Since the seminal studies by Sayers (Ergonomics 16:17-32, 1973) and Akselrod et al. (Science 213:220-222, 1981) a few decades ago, it became clear that beat-by-beat oscillations in RR interval length (i.e. heart-rate variability [HRV]) contain information on underlying neural-control mechanisms based on the instantaneous balance between parasympathetic and sympathetic innervation. Over the years, the number of studies addressing HRV has increased markedly and now outnumbers 23,000. Despite such a large interest, there is still a continuing debate about interpretation of indices produced by computer analysis of HRV.The main part of studies relies on spectral techniques to extract parameters that are linked to hidden information. The general idea is that these proxies of autonomic regulation can be useful to clinical applications in various conditions in which autonomic dysregulation may play a role. There are, however, serious shortcomings related to algorithms, interpretation, and the hidden value of individual indices. In particular, it appears that specific training is necessary to interpret the hidden informational value of HRV. This technical complexity represents a severe barrier to large-scale clinical applications. Moreover, important differences in HRV separate the sexes, and age plays an additional confounding role.We present here a preliminary application of a novel unitary index of RR variability (Autonomic Nervous System Index of cardiac regulation) capable of providing information on the performance of autonomic regulation using a percentile rank position as projected on a large benchmark population. A summary of the underlying sympatho-vagal model is also presented.

Electrocardiograms in Healthy North American Children in the Digital Age.

BACKGROUND: Interpretation of pediatric ECGs is limited by lack of accurate sex- and race-specific normal reference values obtained with modern technology for all ages. We sought to obtain contemporary digital ECG measurements in healthy children from North America, to evaluate the effects of sex and race, and to compare our results to commonly used published datasets. METHODS: Digital ECGs (12-lead) were retrospectively collected for children ≤18 years old with normal echocardiograms at 19 centers in the Pediatric Heart Network. Patients were classified into 36 groups: 6 age, 2 sex, and 3 race (white, black, and other/mixed) categories. Standard intervals and amplitudes were measured; mean±SD and 2nd/98th percentiles were determined by age group, sex, and race. For each parameter, multivariable analysis, stratified by age, was conducted using sex and race as predictors. Parameters were compared with 2 large pediatric ECG data sets. RESULTS: Among ECGs from 2400 children, significant differences were found by sex and race categories. The corrected QT interval in lead II was greater for girls compared with boys for age groups ≥3 years (P≤0.03) and for whites compared with blacks for age groups ≥12 years (P<0.05). The R wave amplitude in V6 was greater for boys compared with girls for age groups ≥12 years (P<0.001), for blacks compared with white or other race categories for age groups ≥3 years (P≤0.006), and greater compared with a commonly used public data set for age groups ≥12 years (P<0.0001). CONCLUSIONS: In this large, diverse cohort of healthy children, most ECG intervals and amplitudes varied by sex and race. These differences have important implications for interpreting pediatric ECGs in the modern era when used for diagnosis or screening, including thresholds for left ventricular hypertrophy.

Electrocardiogram Signal Quality Assessment Based on Structural Image Similarity Metric.

OBJECTIVE: We developed an image-based electrocardiographic (ECG) quality assessment technique that mimics how clinicians annotate ECG signal quality. METHODS: We adopted the structural similarity measure (SSIM) to compare images of two ECG records that are obtained from displaying ECGs in a standard scale. Then, a subset of representative ECG images from the training set was selected as templates through a clustering method. SSIM between each image and all the templates were used as the feature vector for the linear discriminant analysis classifier. We also employed three commonly used ECG signal quality index (SQI) measures: baseSQI, kSQI, and sSQI to compare with the proposed image quality index (IQI) approach. We used 1926 annotated ECGs, recorded from patient monitors, and associated with six different ECG arrhythmia alarm types which were obtained previously from an ECG alarm study at the University of California, San Francisco (UCSF). In addition, we applied the templates from the UCSF database to test the SSIM approach on the publicly available PhysioNet Challenge 2011 data. RESULTS: For the UCSF database, the proposed IQI algorithm achieved an accuracy of 93.1% and outperformed all the SQI metrics, baseSQI, kSQI, and sSQI, with accuracies of 85.7%, 63.7%, and 73.8% respectively. Moreover, evaluation of our algorithm on the PhysioNet data showed an accuracy of 82.5%. CONCLUSION: The proposed algorithm showed better performance for assessing ECG signal quality than traditional signal processing methods. SIGNIFICANCE: A more accurate assessment of ECG signal quality can lead to a more robust ECG-based diagnosis of cardiovascular conditions.

Design and validation of a three-instrument toolkit for the assessment of competence in electrocardiogram rhythm recognition.

BACKGROUND: Rapid and accurate interpretation of cardiac arrhythmias by nurses has been linked with safe practice and positive patient outcomes. Although training in electrocardiogram rhythm recognition is part of most undergraduate nursing programmes, research continues to suggest that nurses and nursing students lack competence in recognising cardiac rhythms. In order to promote patient safety, nursing educators must develop valid and reliable assessment tools that allow the rigorous assessment of this competence before nursing students are allowed to practise without supervision. AIM: The aim of this study was to develop and psychometrically evaluate a toolkit to holistically assess competence in electrocardiogram rhythm recognition. METHODS: Following a convenience sampling technique, 293 nursing students from a nursing faculty in a Spanish university were recruited for the study. The following three instruments were developed and psychometrically tested: an electrocardiogram knowledge assessment tool (ECG-KAT), an electrocardiogram skills assessment tool (ECG-SAT) and an electrocardiogram self-efficacy assessment tool (ECG-SES). Reliability and validity (content, criterion and construct) of these tools were meticulously examined. RESULTS: A high Cronbach's alpha coefficient demonstrated the excellent reliability of the instruments (ECG-KAT=0.89; ECG-SAT=0.93; ECG-SES=0.98). An excellent context validity index (scales' average content validity index>0.94) and very good criterion validity were evidenced for all the tools. Regarding construct validity, principal component analysis revealed that all items comprising the instruments contributed to measure knowledge, skills or self-efficacy in electrocardiogram rhythm recognition. Moreover, known-groups analysis showed the tools' ability to detect expected differences in competence between groups with different training experiences. CONCLUSION: The three-instrument toolkit developed showed excellent psychometric properties for measuring competence in electrocardiogram rhythm recognition.

Evolving regulatory paradigm for proarrhythmic risk assessment for new drugs.

Fourteen drugs were removed from the market worldwide because their potential to cause torsade de pointes (torsade), a potentially fatal ventricular arrhythmia. The observation that most drugs that cause torsade block the potassium channel encoded by the human ether-à-go-go related gene (hERG) and prolong the heart rate corrected QT interval (QTc) on the ECG, led to a focus on screening new drugs for their potential to block the hERG potassium channel and prolong QTc. This has been a successful strategy keeping torsadogenic drugs off the market, but has resulted in drugs being dropped from development, sometimes inappropriately. This is because not all drugs that block the hERG potassium channel and prolong QTc cause torsade, sometimes because they block other channels. The regulatory paradigm is evolving to improve proarrhythmic risk prediction. ECG studies can now use exposure-response modeling for assessing the effect of a drug on the QTc in small sample size first-in-human studies. Furthermore, the Comprehensive in vitro Proarrhythmia Assay (CiPA) initiative is developing and validating a new in vitro paradigm for cardiac safety evaluation of new drugs that provides a more accurate and comprehensive mechanistic-based assessment of proarrhythmic potential. Under CiPA, the prediction of proarrhythmic potential will come from in vitro ion channel assessments coupled with an in silico model of the human ventricular myocyte. The preclinical assessment will be checked with an assessment of human phase 1 ECG data to determine if there are unexpected ion channel effects in humans compared to preclinical ion channel data. While there is ongoing validation work, the heart rate corrected J-Tpeak interval is likely to be assessed under CiPA to detect inward current block in presence of hERG potassium channel block.

R-wave peak time at lead II in Chinese healthy adults.

BACKGROUND: Wide QRS complex tachycardia (WCT) is a common arrhythmia. How to differentiate between WCTs is a challenge in clinical practice. Recently R-wave peak time (RWPT) at lead II was reported to be a helpful and simple tool for differentiating WCTs. However, it has remained unknown about the reference range of RWPT at lead II. In present study, we aimed to investigate the reference range of RWPT at lead II in Chinese healthy adults. METHODS: A retrospective study was conducted in the First Affiliated Hospital of Shantou University Medical College in Southern China. Two thousand four hundred healthy adults aged 21-80 years with no history of structural heart diseases were included. RWPT at lead II was determined. RESULTS: Of 2400 healthy adults, 1200 men and 1200 women were included. The differences of age, mean heart rate and mean QRS duration at lead II between male and female were not significant. RWPT ranged from 16 to 42 ms in male while from 16 to 44 ms in female. The 95 % reference range of RWPT in normal male and female are 19.91 ~ 39.55 ms and 21.75 ~ 37.67 ms, respectively. Compared with the female, the male had a significantly longer RWPT at lead II (29.73 ± 5.01 ms vs 29.71 ± 4.06 ms in female, P = 0.000). CONCLUSION: Our study showed that RWPT at lead II is different between male and female. The male had a significantly longer RWPT at lead II than the female.

The Evidence Against Cardiac Screening Using Electrocardiogram in Athletes.

Sudden cardiac death (SCD) in young athletes is publicly remarkable and tragic because of the loss of a seemingly healthy young person. Because many of the potential etiologies may be identified with a preparticipation electrocardiogram (ECG), the possible use of an ECG as a screening tool has received much attention. A good screening test should be cost-effective and should influence a disease or health outcome that has a significant impact on public health. The reality is that the prevalence of SCD is low and no outcome-based data exist to determine whether early detection saves lives. Further, there is insufficient screening infrastructure, and the risk of screening and follow-up may be higher than that of the actual disease. Until outcomes data demonstrate a benefit with regard to SCD, universal screening cannot be recommended.

Syncope Best Practices: A Syncope Clinical Practice Guideline to Improve Quality.

OBJECTIVE: To determine whether implementation of a standardized clinical practice guideline (CPG) for the evaluation of syncope would decrease practice variability and resource utilization. DESIGN: A retrospective review of medical records of patients presenting to our practice for outpatient evaluation of syncope before and after implementation of the CPG. The guideline included elements of history, physical exam, electrocardiogram, and "red flags" for further testing. SETTING: Outpatient pediatric cardiology offices of a large pediatric cardiology practice. PATIENTS: All new patients between 3 and 21 years old, who presented to cardiology clinic with a chief complaint of syncope. INTERVENTIONS: The CPG for the evaluation of pediatric syncope was presented to the providers. OUTCOME MEASURES: Resource utilization was determined by the tests ordered by individual physicians before and after initiation of the CPG. Patient final diagnoses were recorded and the medical records were subsequently reviewed to determine if any patients, who presented again to the system, were ultimately diagnosed with cardiac disease. RESULTS: Of the 1496 patients with an initial visit for syncope, there was no significant difference in the diagnosis of cardiac disease before or after initiation of the CPG: (0.6% vs. 0.4%, P = .55). Electrocardiography provides the highest yield in the evaluation of pediatric syncope. Despite high compliance (86.9%), there were no overall changes in costs ($346.31 vs. $348.53, P = .85) or in resource utilization. There was, however, a decrease in the variability of ordering of echocardiograms among physicians, particularly among those at the extremes of utilization. CONCLUSIONS: Although the CPG did not decrease already low costs, it did decrease the wide variability in echo utilization. Evaluation beyond detailed history, physical exam, and electrocardiography provides no additional benefit in the evaluations of pediatric patients presenting with syncope.

Protocolos de encaminhamento da atenção básica para a atenção especializada: cardiologia / Primary care referral protocols for specialized care: cardiology

Este material tem como objetivo orientar as equipes que atuam na AB, qualificando o processo de referenciamento de usuários para outros serviços especializados. É uma ferramenta, ao mesmo tempo, de gestão e de cuidado, pois tanto guiam as decisões dos profissionais solicitantes quanto se constitui como referência que modula as avaliações apresentadas pelos médicos reguladores.

Comparative assessment of ascending aortic aneurysms in Marfan patients using ECG-gated computerized tomographic angiography versus trans-thoracic echocardiography.

BACKGROUND: Contrast-enhanced computed tomography (CT) is routinely used as a complementary technique to trans-thoracic echocardiography (TTE) for assessing thoracic aortic aneurysms (TAA). However different measures can be obtained on CT and there are no recommendations on which to use. The objective was to determine which CT measurements most closely match reference TTE measurements in Marfan patients with TAA. METHODS: TTE measurements were obtained using the leading edge-to-leading edge technique in end-diastole on the parasternal longitudinal view. ECG-gated CT measurements were obtained, using the inner-to-inner technique in end-diastole by double oblique reconstruction: on three-cavity view (3C), left ventricle-aorta view (LVAo), and strict transverse plane passing through the maximal diameter "cusp to commissure" and "cusp to cusp" for each cusp. CT and TTE were performed within one month. RESULTS: 44 Marfan patients (39 ± 19 years, 48% men) were included. Dilatation of the ascending aorta was maximal at the level of the sinuses (TTE diameters: mean 47.5 ± 5.3 mm). TTE diameters were similar to 3C, LVAo (mean differences: 2.2 and -0.1 mm, p=NS) and to the three "cusp to cusp" diameters (mean differences ranging from 0 to 1.1mm, p=NS), whereas "cusp to commissure" diameters were all statistically smaller than TTE (3.6 mm, 2.9 mm and 3.7 mm, p ≤ 0.01). CONCLUSIONS: Inner-to-inner "cusp to cusp" diameter measured on an ECG-gated CT should be used for comparison with 2D TTE aortic diameter at the level of the sinuses of Valsalva in patients with thoracic aortic aneurysms.

Echocardiography in hypertension: a call for standardization from the Working Group on Heart and Hypertension of the Italian Society of Hypertension.

The variety of clinical information provided by the echocardiogram (i.e. assessment of left ventricular (LV) structure and geometry, systolic/diastolic function, left atrial and aortic size) in addition to its superior sensitivity for LV hypertrophy detection compared to electrocardiogram are strong arguments supporting the paramount importance of this technique in the assessment of hypertensive heart disease. A number of limitations of the echocardiographic technique, however, including lack of standardized/quantitative procedures, impair its diagnostic accuracy and cost-effectiveness. The aim of these recommendations is to provide a document on the minimum acceptable requirements for the clinical practice of echocardiography in the hypertensive setting and thus to improve the quality of this fundamental tool in the cardiovascular risk stratification of hypertensive patients.

Should we pay the student? A randomised trial of financial incentives in medical education.

BACKGROUND: Financial incentives are effective in moderating physician and patient behaviour, but they have not been studied in the context of medical education. AIM: This study assessed whether financial incentives can motivate students to acquire electrocardiogram (ECG) interpretation skills. METHODS: Students enrolled for a cardio-respiratory teaching module (n = 121) were randomised to an intervention (financial incentive) or a control (book voucher raffle) condition. All students took three validated exams of ECG interpretation skills (at module entry, module exit and seven weeks later). Only the exit exam was financially incentivised in the intervention group. The primary outcome was the proportion of students who correctly identified ≥60% of clinically important diagnoses in the exit exam. RESULTS: Financial incentives more than doubled the odds of correctly identifying ≥60% of diagnoses in the exit exam (adjusted odds ratio 2.44, 95% confidence interval 1.05-5.67) and significantly increased student learning time. However, there was no significant effect on performance levels in the retention exam. CONCLUSIONS: Financial incentives increase reported learning time and examination results in the short-term. The lack of a sustained effect on performance suggests that financial incentives may foster a superficial or strategic rather than a deep approach to learning.