Jean Paul Broustet

Successful retrieval of a lost coronary stent from the descending aorta using a loop basket intravascular retriever set

Delivery of a balloon-expandable stent was complicated by a systemic embolisation. The radio-opaque stent was lost in the descending aorta, but then removed by using a loop basket intravascular retriever set without any peripheral arterial complication.

Flecainide-induced Increase in QRS Duration and Proarrhythmia during Exercise

SummaryIn patients taking flecainide, exercise-induced arrhythmias are believed to be related to QRS widening at rest and during exercise. Our aim was to determine, retrospectively, predictive factors of flecainide-induced (a) QRS widening at rest and during exercise, and (b) proarrhythmia (PA) during exercise. Flecainide was administered to 119 patients for atrial and/or ventricular arrhythmias who performed a maximal treadmill test. A total of 63 patients had a normal heart (defined by the absence of structural heart disease and an ejection fraction ≥ 55% by echocardiography and/or cardiac catheterisation), 26 had coronaropathy, 18 valvulopathy and 3 had both, and 7 had dilated and 2 hypertrophic cardiomyopathy. The mean dosage of flecainide was 190 or 200 ± 10 mg/day. Previous myocardial infarction (MI) was a predictive variable of flecainide-induced QRS widening at rest (p = 0.04). During exercise, the risk factors of QRS widening were previous MI (p = 0.008), angina without previous MI (p = 0.009), structural heart disease (p = 0.001) and a bundle branch block at rest (p = 0.01). PA on exercise occurred in 7 patients. Structural heart disease (p = 0.04) and an impaired left ventricular ejection fraction (LVEF) [p = 0.02] were predictive variables of PA. All patients with left ventricular dysfunction and PA had a QRS widening with flecainide at rest ≥ 25%. The risk factors of QRS widening at rest and during exercise with flecainide were distinct from those of PA on exercise. In patients with an impaired LVEF, a flecainide-induced QRS widening of 25% at rest was the threshold value beyond which there was a high risk of PA during exercise. This study was retrospective and not a double-blind trial, therefore the results need to be corroborated in a prospectively designed trial.

Acute Myocardial Infarction During Transesophageal Echocardiography

We describe the occurrence of acute myocardial infarction during transesophageal echocardiography (TEE) in a patient with atrial fibrillation and underestimated angina. Such a case has not been previously reported in the literature. This case illustrates one of the possible complications of TEE, leading us to suggest systematic sedation in patients with angina in whom TEE is envisaged.

Irregular Ventricular Stimulation in the DDI Mode of a Dual Chamber Pacemaker With Atrial‐Based Lower Rate Timing

This report describes two patients with atrial fibrillation in whom an implanted CHORUS DDD pacemaker programmed to the DDI mode produced an irregular ventricular stimulation rate. The lower rate timing of these devices is atrial‐based only when an atrial event opens an AV interval shorter than the programmed AV delay. In the DDI mode, if Api represents the time when an atrial paced event (Ap) would have occurred if it had not been inhibited by a previous atrial sensed event (As), then Api‐Vp constitutes the implied AV interval where Vp is a paced ventricular event. Although the As‐Vp interval (As‐Api+Api‐Vp) generates an atrial refractory period during its entire duration, the pacemaker can sense an atrial event (Ar) during the implied AV interval. Ar cannot start another AV delay, but it can initiate the atrial‐based lower rate interval. This timing mechanism can cause irregular prolongation of Vp‐Vp intervals to a value longer than the programmed lower interval with a maximal extension equal to the programmed AV delay. Such behavior of the CHORUS pacemaker should not be interpreted as malfunction.

Effect of atrioventricular synchronous pacing on cardiac output determined by CO2 rebreathing at constant submaximal exercise

This study compared cardiac output assessed by a noninvasive CO2 rebreathing method at identical submaximal exercise and heart rate response in patients undergoing DDD or VVI pacing. Our results did not show any hemodynamic superiority of AV synchronous pacing.