BACKGROUND Cardiac memory refers to the observation that altered cardiac electrical activation results in repolarization changes that persist after the restoration of a normal activation pattern. Animal studies, however, have yielded disparate conclusions, both regarding the spatial pattern of repolarization changes in cardiac memory and the underlying mechanisms. The present study was undertak...

The heart is a pump. The objective of cardiac pacing is to improve the cardiac output. The most popular method of cardiac pacing (RV) is not physiologic and results in reduced stroke output when compared to that of normal sinus or atrial paced rhythm. Recognition of pacemaker induced low output states and pacemaker aggravated neurological symptoms has quickened interest in physiologic atrial pa...

BACKGROUND To evaluate, with different pacing modes, acute changes in left ventricular systolic function, obtained by continuous cardiac output thermodilution in various subsets of patients undergoing cardiopulmonary bypass surgery. Increments of mean arterial pressure and cardiac output were considered the end point. METHODS Fifty cases electively submitted to cardiac surgery were analyzed. ...

OBJECTIVES The aim of this study was to assess the potential acute benefit of multisite cardiac pacing with optimized atrioventricular synchrony and simultaneous biventricular pacing in patients with drug-refractory congestive heart failure (CHF). BACKGROUND Prognosis and quality of life in severe CHF are poor. Various nonpharmacological therapies have been evaluated but are restricted in the...

The effect of afterload reduction was studied in a group of patients who remained breathless or tired after permanent ventricular pacing. Haemodynamic measurements were made before and after giving hydralazine 20 mg intravenously using a triple lumen thermodilution catheter and cuff blood pressure recordings during ventricular pacing at the standard rate of 71/min or an increased rate of 88/min...