Vicente López-Merino

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Because of its electrophysiological effects, hypothermia can influence the mechanisms that intervene in the sustaining of ventricular fibrillation. We hypothesized that a rapid and profound reduction of myocardial temperature impedes the maintenance of ventricular fibrillation, leading to termination of the arrhythmia. High-resolution epicardial mapping(More)
OBJECTIVE An evaluation is made of the acute modifications in the wavelength of the atrial excitation process induced by atrial stretching. MATERIAL AND METHODS In 10 isolated Langendorff-perfused rabbit hearts and using a multiple electrode the wavelength of the atrial activation process (functional refractory period x conduction velocity) was determined(More)
The electrophysiological effects of RF ablation upon the areas in proximity to the lesioned zones have not yet been well characterized. An experimental model is used to investigate atrial conduction in the boundaries of RF damaged zones. In 11 isolated and perfused rabbit hearts, endocardial atrial electrograms were recorded using an 80-lead multiple(More)
BACKGROUND The purpose of this study was to determine whether the myocardial electrophysiological properties are useful for predicting changes in the ventricular fibrillatory pattern. METHODS AND RESULTS Thirty-two Langendorff-perfused rabbit hearts were used to record ventricular fibrillatory activity with an epicardial multiple electrode. Under control(More)
A method for quantitating esophagus sensibility by an electric stimulation test is described. Square stimulus waveform at different voltages and durations were transmitted to the esophagus, three series of electric stimuli being used in successive durations (0.5, 1, 2, 4, 8 and 16 ms); in each series the voltage discharge was increased progressively from 0(More)
BACKGROUND Resting ST-segment elevation on Q leads after an acute myocardial infarction has been related to a greater infarct size. Otherwise, the relation between exercise-induced ST-segment elevation and myocardial viability is controversial. We investigated the relation between ST-segment elevation on Q leads at rest and during exercise and regional(More)
The influence of the timing of a nontransmitted or transmitted atrial impulse on the atrioventricular (AV) conduction time of the subsequent impulse was studied in nine isolated rabbit hearts. AV conduction curves were determined by applying the atrial extrastimulus test. The extrastimulus was delivered preceded or not by an interposed atrial impulse whose(More)
High resolution mapping techniques are used to analyze the changes in atrial activation patterns produced by contiguous RF induced lesions. In 12 Langendorff-perfused rabbit hearts, left atrial activation maps were obtained before and after RF induction of epicardial lesions following a triple-phase sequential protocol: (phase 1) three separate lesions(More)
We studied the wall motion of the noninfarcted area and its role in left ventricular remodeling. The study group consisted of 43 patients with a first Q-wave acute myocardial infarction and single-vessel disease. Cardiac catheterization was performed at the first week, and was repeated six months later. Left ventricular volumes, wall motion at the infarcted(More)
An experimental model is used to analyze the effects of ventricular stretching and verapamil on the activation patterns during VF. Ten Langendorff-perfused rabbit hearts were used to record VF activity with an epicardial multiple electrode before, during, and after stretching with an intraventricular balloon, under both control conditions and during(More)