New prognostic score for stable coronary disease evaluation.

Background: The need to improve the exercise testing accuracy, pushed the development of scores, whose applicability was already broadly recognized.

Objective: Prognostic evaluation of stable coronary disease through a new simplified score.

Methods: A new score was applied in 372 multivessel coronary patients with preserved ventricular function, 71.

Electrovectorcardiographic diagnosis of left septal fascicular block: anatomic and clinical considerations.

Several publications considering anatomical, histological, pathological, electrocardiographic, vectorcardiographic, and electrophysiologic studies have shown that the left bundle branch splits into three fascicles or in a "fan-like interconnected network" in the vast majority of human hearts. The left His system is trifascicular with a left anterior, a left posterior, and a left septal fascicle (LSF). Consequently, the classic term "hemiblock," to describe the block of one of the fascicles, established several decades ago by the Rosembaum's school, should be updated.

[Electrocardiographic score: application in exercise test for the assessment of ischemic preconditioning].

Background: the time for 1.0 mm ST-segment depression (T-1.0mm) adopted to characterize ischemic preconditioning (IPC) in sequential exercise tests is consistent and reproducible; however, it has several limitations.

Treadmill exercise testing of asymptomatic men and women without evidence of heart disease.

The aim of this study was to test the hypothesis of differences in performance including differences in ST-T wave changes between healthy men and women submitted to an exercise stress test. Two hundred (45.4%) men and 241 (54.

Relationship among amiodarone, new class III antiarrhythmics, miscellaneous agents and acquired long QT syndrome.

Class III drugs prolong the QT interval by blocking mainly the delayed rectifier rapid potassium outward current (IKr), with little effect on depolarization. This K(+) channel in encoded by the human ether-a-go-go-related gene (hERG). Inhibition of hERG potassium currents by class III antiarrhythmic drugs causes lengthening of cardiac action potential, which produces a beneficial antiarrhythmic effect.

Wellens syndrome associated with prominent anterior QRS forces: an expression of left septal fascicular block?

Wellens syndrome is a clinical-electrocardiographic entity also referred to as left anterior descending (LAD) coronary T-wave syndrome or acute coronary T-wave syndrome. It is a complex of symptoms and signals indicating the existence of an undesirable condition secondary to critical high-grade proximal stenosis of the LAD coronary artery characterized by the association of prior history of acute coronary syndrome with little or no elevation of markers of myocardial damage (unstable angina) and characteristic electrocardiographic changes consistent with subepicardial anterior ischemic pattern (persistently symmetrical, deep negative and broad-based T waves) or plus-minus T waves with inversion of the terminal portion in the LAD coronary artery territory (V1 through V5 or V6). We present a case of a variant of Wellens syndrome that reveals association and, transitorily, the criteria described in literature for left septal fascicular block.

The history of left septal fascicular block: chronological considerations of a reality yet to be universally accepted.

There are several papers in literature that prove in a conclusive and incontestable way, that the left branch of the His bundle, in most instances (85% of the cases) splits into three fascicles of variable morphological pattern, and not into two: left anterior fascicle (LAF), left posterior fascicle (LPF), and left septal fascicle (LSF). The abovementioned papers have anatomical, histological, anatomo-pathological, electrocardiographic, and vectocardiographic, body surface potential mapping or ECG potential mapping and electrophysiological foundation.Additionally, the mentioned papers have been performed both in animal models (dogs) and in the human heart.

Significance of vectorcardiogram in the cardiological diagnosis of the 21st century.

Until the mid-1980s, it was believed that the vectorcardiogram presented a greater specificity, sensitivity and accuracy in comparison to the conventional electrocardiogram, in the diagnosis of the different heart diseases. Recent studies revealed that the vectorcardiogram still is superior to the electrocardiogram in very specific situations, such as in the evaluation of electrically inactive areas, in intraventricular conduction disorders combined and/or in association to inactive areas, in the identification and location of ventricular preexcitation, in the differential diagnosis of patterns varying from normal of electrical axis deviation, in the evaluation of particular aspects of Brugada syndrome, and in the estimation of the severity of some enlargements, among others. With the advent of computerized vectorcardiography, a technology that improves the processing and recording method; a future still promising is expected for this methodology.

Radiofrequency catheter ablation of premature ventricular contractions originating in the right ventricular outflow tract.

Objectives: To evaluate if radiofrequency catheter ablation is an effective procedure for the treatment of right ventricular outflow tract premature ventricular contractions (RVOT-PVC) and ascertain if it results in an improvement of symptoms.

Methods: A prospective study with 30 consecutive patients (mean age 40 +/- 13 years, 25 females), with no apparent structural cardiopathy, with very frequent (mean density of 1,263 +/- 593/h) RVOT-PVC, symptomatic for more than one year (mean = 74 months) and resistant to antiarrhythmic drugs (3 +/- 1.7, including beta-blockers), who underwent radiofrequency catheter ablation.

The signal-averaged electrocardiogram of atrial activation in patients with or without paroxysmal atrial fibrillation.

Objective: To analyze the parameters of the time domain P-wave signal-averaged electrocardiogram (P-SAECG) and compare them with the P-wave duration on the conventional electrocardiogram (P on ECG) as well as the left atrium diameter (LAD) and left ventricular ejection fraction (EF) obtained on the echocardiogram in order to evaluate patients with paroxysmal atrial fibrillation (PAF).

Methods: One hundred and eighty-one patients were included in the study: 117 with confirmed PAF and 64 without PAF. The P-SAECG parameters used were: the filtered P-wave duration (FPD), the root mean square (RMS) voltages in the last 40, 30 and 20 ms of the filtered P-wave (RMS 40, RMS 30 and RMS 20), the root mean square voltage of the filtered P-wave potentials (RMS P), the integral of the potentials during the filtered P-wave (Integral P) and the filtered P-wave late potential durations below 3 microV (PL<3).

Effect of a hypoglycemic agent on ischemic preconditioning in patients with type 2 diabetes and stable angina pectoris.

Objective: Ischemic preconditioning is an increased tolerance to myocardial ischemia during the second of two consecutive exercise tests. ATP-sensitive K(+) channel blockers, such as glinides and sulfonylurea drugs, can induce loss of ischemic preconditioning. This study aimed to investigate the effects of repaglinide, a hypoglycemic agent with an affinity for myocardial ATP-sensitive K (+)channels, on the results of consecutive exercise tests in patients with diabetes and multivessel coronary artery disease.

Time domain analysis of the signal averaged electrocardiogram to detect late potentials in heart failure patients with different etiologies.

Objective: To evaluate the frequency, clinical correlations and prognosis influence of late potentials on the of heart failure patients with different etiologies using the signal averaged electrocardiogram.

Methods: A 42 month study of the signal averaged electrocardiograms of 288 heart failure patients with different etiologies was conducted. The group of patients included 215 males (74.

Exercise stress testing before and after successful multivessel percutaneous transluminal coronary angioplasty.

Controversy exists regarding the diagnostic accuracy, optimal technique, and timing of exercise testing after percutaneous coronary intervention. The objectives of the present study were to analyze variables and the power of exercise testing to predict restenosis or a new lesion, 6 months after the procedure. Eight-four coronary multi-artery diseased patients with preserved ventricular function were studied (66 males, mean age of all patients: 59 +/- 10 years).

The effects of glibenclamide, a K(ATP) channel blocker, on the warm-up phenomenon.

Background: The warm-up phenomenon observed after the second of two sequential exercise tests is characterized by an increased time to ischemia and ischemic threshold, and the latter is related to ischemic preconditioning. Previous studies have demonstrated that a single dose of glibenclamide, a cardiac ATP-sensitive K (K(ATP)) channel blocker, prevents ischemic preconditioning. This study aimed to investigate the effects of chronic treatment with glibenclamide during two sequential exercise tests.

Late coronary artery recanalization effects on left ventricular remodelling and contractility by magnetic resonance imaging.

Aims: To assess the recanalization effects of post-myocardial infarction (MI) on left ventricular (LV) remodelling and contractility in relation to conservative therapy.

Methods And Results: Thirty-six patients with occluded infarct-related artery between 12 h and 14 days post-anterior MI were randomized to percutaneous coronary intervention (PCI group) or conservative therapy (no-PCI group). Magnetic resonance imaging was performed at enrollment and after 6 months.

Brugada syndrome with atypical ECG: downsloping ST-segment elevation in inferior leads.

We present an unusual case of a young Thai immigrant, symptomatic, who had suffered prior episodes of syncope with strong family background: male, first-degree relatives, younger than 45 years old who had died suddenly. The rest ECG, with the patient asymptomatic at the time, showed persistent ST-segment elevation, in inferior leads and "mirror" image in the anterior wall, which were not modified with sublingual nitrates, in absence of demonstrable structural heart disease by chest X-rays and echocardiogram, hypothermia, ischemia, or electrolytic disorders. Holter monitoring revealed at dawn, a short episode of polymorphic ventricular tachycardia of short onset extrasystole coupling, which evolved into asystole and sudden cardiac death.

[Anatomo-clinical correlation. Case 4/2003 - A 61 year-old patient Chagasic woman, with ventricular dysfunction, recurrent ventricular tachycardia and cardiac pacemaker, presented asystole after surgical resection of apical aneurysm].

A 61 year-old Chagasic woman, with previous left ventricular systolic disfunction, ventricular tachychardia and cardiac pacemaker, presented cardiac arrest in asystolia after surgical ressection of apical aneurysm.