The electrocardiogram in heart failure

ECG and Biomarker Profile in Patients with Acute Heart Failure: A Pilot Study

Background: Biomarkers, electrocardiogram (ECG) and Holter ECG are basic, accessible and feasible cardiac investigations. The combination of their results may lead to a more complex predictive model that may improve the clinical approach in acute heart failure (AHF). The main objective was to investigate which ECG parameters are correlated with the usual cardiac biomarkers (prohormone N-terminal proBNP, high-sensitive cardiac troponin I) in patients with acute heart failure, in a population from Romania. The relationship between certain ECG parameters and cardiac biomarkers may support future research on their combined prognostic value. Methods: In this prospective case-control study were included 49 patients with acute heart failure and 31 participants in the control group. For all patients we measured levels of prohormone N-terminal proBNP (NT-proBNP), high-sensitive cardiac troponin I (hs-cTnI) and MB isoenzyme of creatine phosphokinase (CK-MB) and evaluated the 12-lead ECG and 24 h Holter monitoring. Complete clinical and paraclinical evaluation was performed. Results: NT-proBNP level was significantly higher in patients with AHF (p < 0.001). In patients with AHF, NT-proBNP correlated with cQTi (p = 0.027), pathological Q wave (p = 0.029), complex premature ventricular contractions (PVCs) (p = 0.034) and ventricular tachycardia (p = 0.048). Hs-cTnI and CK-MB were correlated with ST-segment modification (p = 0.038; p = 0.018) and hs-cTnI alone with complex PVCs (p = 0.031). Conclusions: The statistical relationships found between cardiac biomarkers and ECG patterns support the added value of ECG in the diagnosis of AHF. We emphasize the importance of proper ECG analysis of more subtle parameters that can easily be missed. As a non-invasive technique, ECG can be used in the outpatient setting as a warning signal, announcing the acute decompensation of HF. In addition, the information provided by the ECG complements the biomarker results, supporting the diagnosis of AHF in cases of dyspnea of uncertain etiology. Further studies are needed to confirm long-term prognosis in a multi-marker approach.

Development and Validation of a Electrocardiographic Diagnostic Score of Heart Failure Among Patients with Hypertension Attending a Tertiary Hospital in Ibadan, Nigeria: The RISK-HHF Case-Control Study

Objectives

Hypertension is the leading cause of HF in sub-Saharan Africa. Electrocardiography (ECG) is a cheap and easily available stratification tool for the diagnosis and prognostication of individuals with hypertension. The aim of this study was to develop an ECG-based HF diagnostic score among patients with hypertension attending a specialist cardiology clinic.

Methods

One hundred and one (101) case-control age- and sex-matched pairs were recruited. The study population were adults with a clinical diagnosis of hypertensive HF failure (cases) and systemic hypertension without HF (controls). Participants underwent clinical assessment and ECG. Associations between ECG variables and HF risk were tested with chi square test. Logistic regression modelling (age- and sex adjusted) was trained on a random subset of participants and tested on the remaining participants to determine the ECG abnormalities that are diagnostic of HF and develop a HF diagnostic score. The HF diagnostic score was then validated in an independent dataset of the ECG-Hypertension Audit. Goodness of fit and c-statistics of the HF summed diagnostic score in the training, testing and validation datasets are presented. A two-sided p value of <0.05 was considered statistically significant.

Results

The independent ECG diagnostic markers of HF among hypertensive patients in this study in decreasing order of effect size were sinus tachycardia (aOR: 7.72, 95% CI: 2.31-25.85). arrhythmia (aOR: 7.14, 95% CI: 2.57-19.86), left ventricular hypertrophy (aOR: 4.47; 1.85-10.77) and conduction abnormality (aOR: 3.41, 95% CI: 1.21-9.65). The HF summed diagnostic score showed excellent calibration and discrimination in the training (Hosmer Lemeshow p = 0.90; c-statistic 0.82; 95% CI 0.76–0.89) and test samples (Hosmer Lemeshow p=0.31; c-statistic 0.73 95% CI 0.60 to 0.87) of the derivation cohort and an independent validation audit cohort (Hosmer Lemeshow p = 0.17; c-statistic 0.79 95% CI 0.74 to 0.84) respectively. The model showed high diagnostic accuracy in individuals with different intermediate pre-test probabilities of HF.

Conclusions

A ECG based HF score consisting of sinus tachycardia, arrhythmia, conduction abnormality and left ventricular hypertrophy is diagnostic of HF especially in those with intermediate pre-test probability of HF. This has clinical importance in the stratification of individuals with systemic hypertension.

Management protocols for chronic heart failure in India

Heart failure is a common clinical syndrome and a global health priority. The burden of heart failure is increasing at an alarming rate worldwide as well as in India. Heart failure not only increases the risk of mortality, morbidity and worsens the patient's quality of life, but also puts a huge burden on the overall healthcare system. The management of heart failure has evolved over the years with the advent of new drugs and devices. This document has been developed with an objective to provide standard management guidance and simple heart failure algorithms to aid Indian clinicians in their daily practice. It would also inform the clinicians on the latest evidence in heart failure and provide guidance to recognize and diagnose chronic heart failure early and optimize management.

Automated diagnosis of congestive heart failure using dual tree complex wavelet transform and statistical features extracted from 2s of ECG signals

Identification of alarming features in the electrocardiogram (ECG) signal is extremely significant for the prediction of congestive heart failure (CHF). ECG signal analysis carried out using computer-aided techniques can speed up the diagnosis process and aid in the proper management of CHF patients. Therefore, in this work, dual tree complex wavelets transform (DTCWT)-based methodology is proposed for an automated identification of ECG signals exhibiting CHF from normal. In the experiment, we have performed a DTCWT on ECG segments of 2s duration up to six levels to obtain the coefficients. From these DTCWT coefficients, statistical features are extracted and ranked using Bhattacharyya, entropy, minimum redundancy maximum relevance (mRMR), receiver-operating characteristics (ROC), Wilcoxon, t-test and reliefF methods. Ranked features are subjected to k-nearest neighbor (KNN) and decision tree (DT) classifiers for automated differentiation of CHF and normal ECG signals. We have achieved 99.86% accuracy, 99.78% sensitivity and 99.94% specificity in the identification of CHF affected ECG signals using 45 features. The proposed method is able to detect CHF patients accurately using only 2s of ECG signal length and hence providing sufficient time for the clinicians to further investigate on the severity of CHF and treatments.

Practices of Clinical Examination of Heart Failure Patients in Primary Health Care

The aim of this cross-sectional cohort study was to examine practices of clinical examination of heart failure patients in three primary health care regions in northern Finland. Altogether, 825 randomly selected heart failure patients aged 45 years or older, who had special reimbursement for drugs for the treatment of heart failure, were included. Main outcome measures were the frequency of medical visits and the mode of clinical examinations during control visits and symptomatic visits due to heart failure made by general practitioners. The prevalence of heart failure was 2% among those aged 45-75 years and 18% among the older ones. No differences existed in the incidence of all medical visits made as a result of heart failure, between the regions. ECG recordings, auscultation of the heart and lungs, measurements of blood pressure and recordings of ankle swelling were carried out in 72%, 79%, 85%, 90% and 59% of cases of control visits, and in 78%, 63%, 79%, 77% and 49% of cases in symptomatic visits, respectively. Chest X-ray examinations and recording of liver size were seldom carried out: 16% and 12% in control visits, and 19% and 11% in symptomatic visits, respectively. Important prognostic markers of heart failure were recorded even more rarely: jugular venous pressure, in 1% of control visits and 3% of symptomatic visits and the third heart sound not at all. NYHA grading had been carried out in 8% and echocardiography in 13% of cases. The prevalence of heart failure was higher than in many clinical studies, suggesting high number of false positive heart failure diagnoses made in primary health care. Some clinical examinations of significant prognostic value in heart failure are underused by general practitioners. Therefore, further education among general practitioners is needed to improve the practices of clinical examination in heart failure patients.