Predictors of Higher Frequency of Atrial Fibrillation in Patients with Cardiac Resynchronization Therapy.

Background and Objectives: Cardiac resynchronization therapy (CRT) is one of the effective therapeutic options in the treatment of systolic heart failure (HF) with persistent symptoms. This prospective study was designed to determine whether CRT with biventricular pacing would reduce the risk of development of atrial fibrillation (AF) and to identify predictors for AF occurrence. Materials and Methods: The study population consisted of 126 patients, with a mean age of 63.8 ± 9.1 years, who were eligible for CRT with biventricular pacing. Inclusion criteria were left ventricular ejection fraction (LVEF) ≤ 35%, QRS duration ≥ 130 msec, and persistent HF symptoms of New York Heart Association (NYHA) II or III, despite optimal drug therapy. Patients were followed for a period of 24 months and were evaluated through clinical, electrocardiographic, and echocardiographic examination at baseline (prior to CRT implantation), as well as at 6 and 24 months post-implantation. At the end of follow-up, patients were divided into clinical responders and non-responders based on the following criteria: decrease in NYHA class ≥ I, increase in LVEF ≥ 10%, and reduction in QRS duration ≥ 20 msec. Results: At follow-up, CRT was associated with a significant increase in LVEF (20.6 ± 6.9% pre-implantation, 32.9 ± 9.3% 24 months after implantation; p < 0.001), reduction in left ventricular end-diastolic and end-systolic diameters, and decrease in QRS duration (167.6 ± 14.3 msec pre-implantation, 131.7 ± 11.7 msec 24 months after implantation; p < 0.001), while left atrial (LA) diameter was slightly increased (p = 0.070). The frequency of AF occurrence increased after two years of follow-up (52.4% to 56.9%, p < 0.001). Significant predictors of AF occurrence in our study population were response to CRT-AF more frequent in non-responders (B = 8.134; p < 0.001), LA diameter-AF more frequent with larger LA diameter (B = 0.813; p < 0.001), and coronary sinus (CS) lead position-AF more frequent with posterolateral in comparison with lateral CS lead position (B = 5.159; p = 0.005). Conclusions: The results of our study provide new data on AF predictors in patients with HF subjected to CRT. There remains a permanent need for new predictors, which might help in patient selection and improvement in response rate.

Acute Coronary Syndrome Presenting during On- and Off-Hours: Is There a Difference in a Tertiary Cardiovascular Center?

Background and Objectives: ACS presents an acute manifestation of coronary artery disease and its treatment is based on timely interventional diagnostics and PCI. It has been known that the treatment and the outcomes are not the same for all the patients with ACS during the working day, depending on the availability of the procedures and staff. The aim of the study was to explore the differences in clinical characteristics and outcomes in patients admitted for ACS during on- and off-hours. Materials and Methods: The retrospective study included 1873 consecutive ACS patients admitted to a tertiary, university hospital that underwent coronary angiography and intervention. On-hours were defined from Monday to Friday from 07:30 h to 14:30 h, while the rest was considered off-hours. Results: There were more males in the off-hours group (on-hours 475 (56%) vs. off-hours 635 (62%); p = 0.011), while previous MI was more frequent in the on-hours group (on 250 (30%) vs. off 148 (14%); p < 0.001). NSTEMI was more frequent during on-hours (on 164 (19%) vs. off 55 (5%); p < 0.001), while STEMI was more frequent during off-hours (on 585 (69%) vs. off 952 (93%); p < 0.001). Patients admitted during on-hours had more multivessel disease (MVD) (on 485 (57%) vs. off 489 (48%); p = 0.006), as well as multivessel PCI (on 187 (22%) vs. off 171 (16%); p = 0.002), while radial access was preferred in off-hours patients (on 692 (82%) vs. off 883 (86%); p = 0.004). Left main PCI was performed with similar frequency in both groups (on 37 (4%) vs. off 35 (3%); p = 0.203). Death occurred with similar frequency in both groups (on 17 (2.0%) vs. off 26 (2.54%); p = 0.404), while major adverse cardio-cerebral events (MACCEs) were more frequent in the on-hours group (on 105 (12.4%) vs. off 70 (6.8%); p = 0.039) probably due to the more frequent repeated PCI (on 49 (5.8%) vs. off 27 (2.6%); p = 0.035). Conclusions: Patients admitted for ACS during working hours in a tertiary hospital present with more complex CAD, have more demanding interventions, and experience more MACCEs during follow-up mostly due to myocardial infarctions and repeated procedures.

Inappropriate shock delivery as a result of electromagnetic interference originating from the faulty electrical installation.

We present a case report of a 74-year-old male patient with an implantable cardioverter defibrillator who suffered an inappropriate defibrillation shock while bathing in the tub. Insight in the ICD stored electrogram episodes revealed electromagnetic interferences, with a typical 50 Hz electrical artifact mimicking fast ventricular tachycardia as a device misinterpreted. After this event, the maintenance workers investigated the electrical installation in the bathroom and revealed that there was voltage leaking between electrical installation and metal pipes. After the repair was completed without any additional programming, the patient has had no subsequent shocks.

Idiopathic premature ventricular complexes treatment: Comparison of flecainide, propafenone, and sotalol.

BACKGROUND: Beta-blockers (BB) or dihydropyridine calcium channel blockers (CCBs) are still the first choices in the treatment of idiopathic premature ventricular complexes (PVCs), with low-modest efficacy. Antiarrhythmic drugs (AADs) of Ic class are moderate to highly efficient but the evidence on their benefits is still limited. AIM: To compare effectiveness and safety of flecainide, propafenone, and sotalol in the treatment of symptomatic idiopathic PVCs. METHODS: Our single-center retrospective study analyzed 104 consecutive patients with 130 medication episodes of frequent idiopathic PVCs treated with AADs flecainide, propafenone (Ic class) or sotalol (III class). The primary outcome was complete/near complete reduction of PVCs after medication episode (PVCs burden reduction >99%), and the secondary outcome was significant PVC burden reduction (≥80%). RESULTS: The complete/near complete PVCs burden reduction occurred in 31% and was significant in 43% of treated patients. A reduction of PVC burden for >99% was achieved in 56% of patients on flecainide, in 11% of patients on propafenone (p = .002), and in 21% of patients receiving sotalol (p = .031). There was no difference between propafenone and sotalol (p = .174). A reduction of PVC burden for ≥80% was achieved in 64% of patients on flecainide, in 30% of patients on propafenone (p = .009), and 33% of patients on sotalol (p = .020). There was no difference between propafenone and sotalol (p = .661). CONCLUSIONS: The efficacy of AADs class Ic and III in the treatment of idiopathic PVCs was modest. Flecainide was the most effective AAD in the achievement of complete/near complete or significant PVC burden reduction, compared to propafenone and sotalol.