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D Blommaert

Publications and source records attributed to D Blommaert.

12 recordsLinked to original sources
PubMed2003

Is a cooled tip catheter the solution for the ablation of the cavotricuspid isthmus?

To test the theoretical superiority of irrigated tip catheters to achieve complete cavotricuspid isthmus block, a 4-mm cooled tip catheter was compared to a conventional 8-mm tip catheter with a double temperature sensor in the cavotricuspid isthmus (CTI) ablation. The study prospectively enrolled 60 patients (47 men, mean 65 +/- 10 years) with common flutter divided in group 1 (n = 30) assigned to an 8-mm tip catheter versus group 2 (n = 30), assigned to an internal circuit, irrigated tip catheter. Linear radiofrequency applications were performed in a point-by-point protocol to achieve complete CTI block. Complete CTI block was achieved in 29 patients in each group. Mean durations of procedure and fluoroscopy were 91 versus 90 and 40 versus 33 minutes in group 1 versus 2, respectively, (NS). The mean number/patient of RF pulses to interrupt atrial flutter was four in group 1 and eight in group 2 (P = 0.034), and 11 and 13, respectively, to interrupt CTI conduction (NS). The total energy delivered was similar in both groups (29,237 vs 23,236 W/s, NS). CTI ablation with a conventional 8-mm tip catheter versus an irrigated tip catheter was associated with similar success rates, procedure duration, and fluoroscopic exposure. The technical complexity of the cooled tip catheter renders it less competitive.

Adult↗
PubMed2000

Prophylaxis of supraventricular and ventricular arrhythmias after coronary artery bypass grafting with low-dose sotalol.

BACKGROUND: Supraventricular tachyarrhythmia (SVT) commonly occurs shortly after coronary artery bypass grafting (CABG), but ventricular arrhythmias are less documented. METHODS: On the 1st postoperative day, 206 consecutive eligible patients were prospectively randomized to a sotalol group (80 mg b.i.d.; n = 103) or a control group without beta-blockade or antiarrhythmic drugs (n = 103). RESULTS: The SVT incidence (predominantly atrial fibrillation) accounted for 16% in the sotalol group versus 48% (p < 0.00001). Multivariate analysis showed that sotalol reduced the SVT incidence (p < 0.00001, odds ratio, 0.20; 95% confidence interval, 0.09 to 0.42), whereas a lower preoperative left ventricular ejection fraction (p = 0.019) and older age (p = 0.031) were independent risk factors of SVT occurrence. The Holter electrocardiographic analysis (24 hours) demonstrated that sotalol (32 versus 92; p = 0.031) decreased the median number of ventricular events, mostly isolated premature ventricular beats. Neither ventricular proarrhythmia effect nor "torsades de pointes" were detected. Despite strict hemodynamic-based selection, sotalol had to be discontinued in 8 patients (7.8%), for reasons related to asthma in 3 or cardiac reasons in 5. CONCLUSIONS: Oral low-dose sotalol provided considerable and reliable protection in selected nondepressed cardiac function patients, reducing the occurrence of both supraventricular and ventricular arrhythmias after CABG.

Administration, Oral↗
PubMed2000

Effective prevention of atrial fibrillation by continuous atrial overdrive pacing after coronary artery bypass surgery.

OBJECTIVES: The present study was aimed to evaluate the efficacy of a specific algorithm with continuous atrial dynamic overdrive pacing to prevent atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery. BACKGROUND: Atrial fibrillation occurs in 30% to 40% of patients after cardiac surgery with a peak incidence on the second day. It still represents a challenge for postoperative prevention and treatment and may have medical and cost implications. METHODS: Ninety-six consecutive patients undergoing CABG for severe coronary artery disease and in sinus rhythm without antiarrhythmic therapy on the second postoperative day were randomized to have or not 24 h of atrial pacing through temporary epicardial wires using a permanent dynamic overdrive algorithm. Holter ECGs recorded the same day in both groups were analyzed to detect AF occurrence. RESULTS: No difference was observed in baseline data between the two study groups, particularly for age, male gender, history of AF, ventricular function, severity of coronary artery disease, preoperative beta-adrenergic blocking agent therapy or P-wave duration. The incidence of AF was significantly lower (p = 0.036) in the paced group (10%) compared with control subjects (27%). Multivariate analysis showed AF incidence to increase with age (p = 0.051) but not in patients with pacing (p = 0.078). It decreased with a better left ventricular ejection fraction only in conjunction with atrial pacing (p = 0.018). CONCLUSIONS: We conclude that continuous atrial pacing with an algorithm for dynamic overdrive reduces significantly incidence of AF the second day after CABG surgery, particularly in patients with preserved left ventricular function.

Adult↗
PubMed1999

Limited internal shocks for atrial fibrillation refractory to external cardioversion.

UNLABELLED: We investigated the feasibility and long-term results of low-energy internal defibrillation using a limited number of shocks in patients with persistent atrial fibrillation resistant to external cardioversion. A relatively high number of shocks of lower energy are usually required in those cases and can be poorly tolerated. METHODS AND RESULTS: Twenty-five patients with persistent atrial fibrillation underwent internal defibrillation, using biphasic R wave synchronous shocks between two catheters in the high right atrium and the coronary sinus. Conversion to sinus rhythm was obtained in all patients, with a median of two shocks. Early recurrence of atrial fibrillation (AF) occurred in eight cases (32%). Seven patients (41%) out of 17 discharged in sinus rhythm remained free of AF after a median follow-up of 8.9 months. Severe mitral insufficiency (P=0.05) and low left ventricle ejection fraction (P=0.002) were correlated with earlier recurrence. Amiodarone significantly favored (P=0.019) maintenance of sinus rhythm. CONCLUSION: Internal defibrillation using a limited number of shocks equal to or less than 30 Joules is effective in terminating refractory atrial fibrillation and could be more acceptable for patients. However, the recurrence rate remains high, particularly in patients with severe mitral insufficiency or poor ventricular function. Amiodarone delays recurrences of atrial fibrillation.

Adult↗
PubMed1999

A young man with recurrent syncopes, right bundle branch block and ST segment elevation.

We report on the case of a 33-year-old man with recurrent syncopes appearing suddenly due to sustained monomorphic ventricular tachycardias. The electrocardiogram (ECG) showed a right bundle branch block pattern and ST segment elevation in the precordial leads V1 to V2, not explained by ischemia, electrolyte disturbances, toxic ingestion, or structural heart disease (coronary and right ventricle angiograms as well as biopsies of the right ventricle were normal). ECG image was compatible with the so-called Brugada syndrome, first described in 1992. This entity is very rare. Missed diagnosis can be disastrous because life-threatening ventricular arrhythmias often develop in patients.

Adult↗
PubMed1999

Multicenter results of TADpole heart wire system used to treat postoperative atrial fibrillation.

OBJECTIVE: Postoperative atrial fibrillation (AF) affects 20-30% of patients undergoing open-heart surgery, delays mobilization and impairs hemodynamics. Implantation of TADpole Heart Wires offers a new method of applying internal low-energy-shocks to terminate AF. The safety and efficacy of the TADpole system to treat postoperative AF was evaluated in this multicenter trial. METHODS: Two atrial wires, configured with a highly flexible 11.5 cm distal shocking and a 0.5 cm proximal pacing electrode were sutured onto the right and left atrium. Upon detection of AF, R-wave synchronized low-energy-shocks were administered via an energy attenuating External Defibrillator Interface Module or ICD programmer. RESULTS: A total of 296 patients (65+/-9.2 years, 74.7% male) have been enrolled to date in six European centers. The wire placement time was 4.2+/-2.2 min, 65 patients had a total of 83 episodes of AF treated by the TADpole Heart Wire system with a conversion rate of 88.5% (approximate energy of 6+/-2 J), early recurrence of AF was observed in ten patients (12.8%). No clinical complications were reported. The shocks were well tolerated with slight sedation. The ease of withdrawal was 2.3+/-1.2 on a graded scale of 0 (easy) to 10 (difficult). CONCLUSIONS: These multicenter results indicate that postoperative atrial cardioversion using TADpole Heart Wires is both safe and efficient. It is expected that hospital length of stay and its associated economic impact can be reduced with this therapy.

Aged↗
PubMed1999

Adaptive mechanisms of arterial and venous coronary bypass grafts to an increase in flow demand.

OBJECTIVE: To compare the mechanisms by which arterial and venous grafts increase their flow during pacing induced tachycardia, early and later after coronary bypass surgery. DESIGN: 43 grafts (13 epigastric artery, 15 mammary artery, 15 saphenous vein) evaluated early (9 (3) days (mean (SD)) after bypass surgery were compared with 41 other grafts (15 epigastric, 11 mammary, 15 saphenous vein) evaluated later after surgery (mean 23 months, range 6 to 168 months) by quantitative angiography and intravascular Doppler velocity analysis during atrial pacing. Controls were 17 normal coronary arteries. RESULTS: Baseline graft flow tended to be lower later after surgery than early (41 (16) v 45 (21) ml/min, NS). Blood flow increased during pacing by 30 (16)% early after surgery, less than later after surgery (+46 (18)%, p < 0.001) and less than in normal coronary arteries (+54 (27)%, p < 0.001 v early grafts; NS v late grafts). There was no difference between venous and arterial grafts. No significant vasodilatation was observed during pacing early after surgery in arterial and venous grafts. Later after surgery, significant vasodilatation was observed only in arterial grafts (mammary and epigastric grafts), from 2.41 (0.37) to 2.53 (0. 41) mm (+5.1% v basal, p < 0.001). Early after surgery and in venous grafts later after surgery, the increase in flow was entirely due to an increase in velocity. In later arterial grafts, the relative contribution of the increase in velocity to the increase in flow during pacing was lower in arterial grafts (70 (22)%) than in venous grafts (102 (11)%, p < 0.001) and similar to normal coronary arteries (68 (28)%). CONCLUSIONS: Early and later after surgery, arterial grafts and venous grafts both increase their flow similarly during pacing. Early arterial grafts and venous grafts increase their flow only through an increase in velocity. Later after surgery, arterial grafts act as more physiological conduits and increase their flow in the same way as normal coronary arteries, through an increase in velocity and calibre mediated by the endothelium.

Adaptation, Physiological↗
PubMed1997

Radiofrequency catheter ablation of sustained monomorphic ventricular tachycardia in hypertrophic cardiomyopathy.

INTRODUCTION: Incessant monomorphic ventricular tachycardia (VT) with a right bundle branch block morphology and a northwest axis is a rare arrhythmic complication in a patient with hypertrophic cardiomyopathy and apical left ventricular aneurysm. METHODS AND RESULTS: The origin of this VT was localized using the following criteria: the presence of entrainment without fusion, equal intervals from the stimulus to the beginning of the QRS complex and from the electrogram to the QRS complex during VT, and the first postpacing interval identical to the tachycardia cycle length. Radiofrequency energy applied to the septoapical part of the apical left ventricular aneurysm terminated the tachycardia within 2 seconds. CONCLUSION: Using criteria to guide radiofrequency (RF) ablation of VT in patients with coronary artery disease, an incessant monomorphic VT in a patient with hypertrophic cardiomyopathy was successfully ablated.

Aged↗