Electrovectorcardiographic study of left ventricular aneurysm in ischemic heart disease.

The aim was to characterize the electrovectorcardiographic pattern of ventricular aneurysms in ischemic cardiopathy by analyzing the cardiac ventricular repolarization. The medical records of 2,670 individuals were analyzed in this cross-sectional study. A test phase included 33 patients who underwent transthoracic echocardiogram with ultrasonic enhancing agent, electrocardiogram, and vectorcardiogram (aneurysm group -  = 22, and akinesia group -  = 11).

Prognostic Evaluation of Microvolt T-Wave Alternans in Hypertrophic Cardiomyopathy: 9-year Clinical Follow-up.

Background: Sudden cardiac death (SCD) resulting from ventricular arrhythmia is the main complication of hypertrophic cardiomyopathy (HCM). Microvolt T-wave alternans (MTWA) is associated with the occurrence of ventricular arrhythmias in several heart diseases, but its role in HCM remains uncertain.

Objective: To evaluate the association of MTWA with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients in a long-term follow-up.

Modified moving average methodology applied to the treadmill stress testing analysis of microvolt T-wave alternans.

Sudden cardiac death is impactful. There has been an increase in the search for tools capable of identifying individuals who are most susceptible, such as the microvolt T-wave alternans. This study aims to analyze the applicability of the modified moving average methodology to obtain the microvolt T-wave alternans using treadmill specific protocols.

Ventricular repolarization abnormalities: the electrocardiographic track of cardiac tumoural involvement in an infant with tuberous sclerosis complex. A case report.

Background: Primary cardiac tumours are rare in children. Against this backdrop, echocardiogram is the main diagnostic procedure, while electrocardiogram (ECG) usually plays a secondary role, by detecting tumoural consequences as cardiac arrhythmias and chambers overload. We describe a case where an electrocardiographic sign was the cornerstone to diagnosis and surveillance of an infant with a cardiac rhabdomyoma.

Applicability of the Electro-Vectorcardiogram in Current Clinical Practice.

The electrocardiogram (ECG) has been reinvigorated by the identification of electrical alterations that were not definitely clarified before. In this context, and mainly regarding the definition of arrhythmogenic substrates, the association of the ECG with the vectorcardiogram (VCG) has gathered much more information about the cardiac electrical phenomena, thus allowing us to differentiate potentially fatal cases from benign ones. Obtaining a VCG concomitantly with the performance of an ECG has led to a significant gain in the definition of extremely sophisticated pathologies, which function suffer some type of structural or dynamic alterations, involving either the reduction or enhancement of ionic channels and currents.

III SBC Guidelines on the Analysis and Issuance of Electrocardiographic Reports - Executive Summary.

The third version of the guidelines covers recently described topics, such as ion channel diseases, acute ischemic changes, the electrocardiogram in athletes, and analysis of ventricular repolarization. It sought to revise the criteria for overloads, conduction disorders, and analysis of data for internet transmission. Resumo A terceira versão das diretrizes aborda tópicos recentemente descritos, como as doenças dos canais iônicos, alterações isquêmicas agudas, o eletrocardiograma dos atletas e análise da repolarização ventricular.

Reproducibility for Heart Rate Variability Analysis during 6-Min Walk Test in Patients with Heart Failure and Agreement between Devices.

Heart rate variability (HRV) analysis is a useful method to assess abnormal functioning in the autonomic nervous system and to predict cardiac events in patients with heart failure (HF). HRV measurements with heart rate monitors have been validated with an electrocardiograph in healthy subjects but not in patients with HF. We explored the reproducibility of HRV in two consecutive six-minute walk tests (6MW), 60-minute apart, using a heart rate monitor (PolarS810i) and a portable electrocardiograph (called Holter) in 50 HF patients (mean age 59 years, NYHA II, left ventricular ejection fraction ~35%).

Exercise-induced quantitative microvolt T-wave alternans in hypertrophic cardiomyopathy.

Background/purpose: Patients with hypertrophic cardiomyopathy (HCM) have elevated risk for sudden cardiac death (SCD). Our study aimed to quantitatively characterize microvolt T-wave alternans (TWA), a potential arrhythmia risk stratification tool, in this HCM patient population.

Methods: TWA was analyzed with the quantitative modified moving average (MMA) in 132 HCM patients undergoing treadmill exercise testing, grouped according to Maron score risk factors as high-risk (H-Risk, n=67,), or low-risk (L-Risk, n=65, without these risk factors).

Rare Association: Chagas' Disease and Hypertrophic Cardiomyopathy.

A woman (49 years) with Chagas' disease showed: ECG, right bundle-branch block and left anterior-superior fascicular block; V1 has unusual R > R', and elevated ST segment from V2 to V6 . Additional imaging revealed concomitant HCM and Chagas, which is uncommon. Overlapping of ECG findings can be explained by this rare association of diseases.