OKHAWA and his colleagues have provided histologic evidence that a lesion in the distal or branching portion of the His bundle, and thus actually within the ventricles, may produce complete atrioventricular (AV) block on the surface ECG associated with "AH" block on the His bundle electrogram (atrial impulses blocked proximal to the His deflection) and that this may be associated with an escape...

The feasibility of internal cardioversion for ventricular tachycardia using a prototype of an implantable cardioverter which delivers a low energy discharge via an intracardiac lead and its acceptability to the patient were studied. The cardioverting discharge was synchronised to the apical right ventricular electrogram. In 29 episodes of ventricular tachycardia (RR interval 250-700 ms) the api...

A 64-year-old woman had been experiencing short episodes of rapid regular heart beating for nearly a year. The bouts became frequent and lengthy, resulting in a hospital admission a month earlier when intravenously administered adenosine terminated an episode. She was discharged on diltiazem, but the bouts of tachycardia continued and were accompanied by light-headedness and sometimes nausea. W...

The QRS loop on the horizontal plane of the vectorcardiogram and the QRS complex in the right praecordial leads of the electrocardiogram were studied in 8o patients with strictly posterior and/or lateral infarction. In all 30 patients with combined posterolateral infarction a ratio RIS greater than I in lead Vi was found. In I9 out of the 23 patients with strictly posterior infarction and in al...

minor discrepancies existing. It is generally accepted that in the presence of anomalous bypass conduction or preexcitation the QRS complexes are the result of a first component due to anomalous bypass conduction and a second component due to the normal atrioventricular conducted impulse. Vera et al.' have shown that the participation of each of these two components in building up or fusing tog...

The purpose of this research is to develop an intuitive and robust realtime QRS detection algorithm based on the physiological characteristics of the electrocardiogram waveform. The proposed algorithm finds the QRS complex based on the dual criteria of the amplitude and duration of QRS complex. It consists of simple operations, such as a finite impulse response filter, differentiation or thresh...

A number of signal processing techniques make use of first-derivative-based approaches for detecting regions of interest in biological signals. For instance, central and five-point derivative-based algorithms are employed for emphasizing and identification of the QRS complex in the ECG signal. Signal differentiation approaches are also used for detection and removal of high-frequency components...

Thoracopagus is the most common form of conjoined twins. Cardiovascular evaluation is necessary to establish the existence of 2 separate hearts before planning surgical separation of the twins. This is usually done by cardiac ultrasound, cardiac catheterization, documenting 2 separate pulse rates on physical examination, and the presence of 2 independent QRS complexes on simultaneously recorded...

The electrocardiographic findings of 1 8 patients with chronic constrictive pericarditis and their progress 16 to 80 months following radical pericardectomy were studied. Atrial fibrillation, abnormal P waves, right QRS axis deviation, low QRS complex voltage in the conventional leads as well as T wave inversion, were the common preoperative electrocardiographic findings. Following radical peri...

BACKGROUND We retrospectively investigated the value of clinical and ECG findings as well as QT-QRS dispersion in predicting the risk of sudden death in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). METHODS AND RESULTS Duration and interlead variability of the QT interval and QRS complex were measured manually from standard ECGs in 20 sudden death victims with ARVC dia...