Effects of propofol on ventricular repolarization and incidence of malignant arrhythmias in adults.

BACKGROUND: Propofol is commonly used for procedural sedation in interventional electrophysiology. However, ventricular arrhythmias under Propofol have been reported. Our aim was to investigate ventricular repolarization and incidence of ventricular arrhythmias under Propofol infusion in adults with cardiac arrhythmias. METHODS: QRS, QTcB (Bazett), QTcFri (Fridericia), JTc, measurement of T peak to Tend time (Tp-e) at baseline and under Propofol infusion was performed in 235 patients. Screening for unexpected ventricular arrhythmias was performed in 1165 patients undergoing EP procedures under Propofol. RESULTS: A significant prolongation of Tp-e under Propofol infusion (79.7±17.3 vs. 86.4±22.5ms, p<0.001) and of QTcFri (429.3±35.8 vs. 435.5±36.5, p=0.033) was detected. No significant change of the QTcB interval, JTc interval or QRS duration was observed. One case (0.09%) of ventricular fibrillation during rapid ventricular pacing under Propofol occurred. CONCLUSION: Although transmural dispersion of ventricular repolarisation is increased under Propofol, incidence of malignant ventricular arrhythmias is low. For evaluation of QT interval under Propofol, Fridericia's correction formula should be used rather than Bazett's formula.

Catheter ablation of premature ventricular contractions in elderly patients: feasibility and success.

BACKGROUND: Catheter ablation has become a standard curative treatment for symptomatic, drug refractory premature ventricular contractions (PVC). The aim of this study was to investigate the efficacy and safety of this procedure in elderly patients. METHODS AND RESULTS: A total of 101 consecutive patients (mean age 50.7 ± 16.9, 53 % women) presenting to our center for ablation of PVC were included and assigned to two age groups (<65 and ≥65 years). Clinical characteristics, procedural parameters, complications and success after 6-month follow up were compared between the two groups. Patients ≥65 years (n = 27) showed a higher rate of hypertension (78 vs. 27 %, p < 0.001), coronary artery disease (19 vs. 12 %, p = 0.01), renal insufficiency (22 vs. 1 %, p < 0.001) and diabetes (22 vs. 3 %, p = 0.001). Left ventricular ejection fraction did not differ between the two groups (56.6 vs. 57.4 %, p = 0.497). In patients <65 years the origin of the PVC was significantly more often in RVOT or LVOT (95 vs. 70 %, p = 0.001). Acute success rates (67 vs. 73 %, p = 0.545) and success rates after 6 months (81 vs. 86 %, p = 0.795) were not different between the two groups. Two complications were observed, both occurred in the <65 years group (1 pericardial effusion and 1 large groin hematoma). CONCLUSION: Catheter ablation of PVC is feasible in elderly patients without overt heart disease. Success rates are not significantly different compared to patients <65 years. Procedural complications are rare in both the groups. Ablation of this arrhythmia can therefore be regarded as a promising curative treatment in advanced age.