Chronic Apical and Nonapical Right Ventricular Pacing in Patients with High-Grade Atrioventricular Block: Results of the Right Pace Study.

OBJECTIVE: The aim of the study was to compare the two approaches to chronic right ventricular pacing currently adopted in clinical practice: right ventricular apical (RVA) and non-RVA pacing. BACKGROUND: Chronic RVA pacing is associated with an increased risk of atrial fibrillation, morbidity, and even mortality. Non-RVA pacing may yield more physiologic ventricular activation and provide potential long-term benefits and has recently been adopted as standard procedure at many implanting centers. METHODS: The Right Pace study was a multicenter, prospective, single-blind, nonrandomized trial involving 437 patients indicated for dual-chamber pacemaker implantation with a high percentage of RV pacing. RESULTS: RV lead-tip target location was the apex or the interventricular septum. RVA (274) and non-RVA patients (163) did not differ in baseline characteristics. During a median follow-up of 19 months (25th-75th percentiles, 13-25), 17 patients died. The rates of the primary outcome of death due to any cause or hospitalization for heart failure were comparable between the groups (log-rank test, p = 0.609), as were the rates of the composite of death due to any cause, hospitalization for heart failure, or an increase in left ventricular end-systolic volume ≥ 15% as compared with the baseline evaluation (secondary outcome, p = 0.703). After central adjudication of X-rays, comparison between adjudicated RVA (239 patients) and non-RVA (170 patients) confirmed the absence of difference in the rates of primary (p = 0.402) and secondary (p = 0.941) outcome. CONCLUSIONS: In patients with indications for dual-chamber pacemaker who require a high percentage of ventricular stimulation, RVA or non-RVA pacing resulted in comparable outcomes. This study is registered with ClinicalTrials.gov (identifier: NCT01647490).

Access to magnetic resonance imaging of patients with magnetic resonance-conditional pacemaker and implantable cardioverter-defibrillator systems: results from the Really ProMRI study.

Aims: The Really ProMRI study evaluates magnetic resonance imaging (MRI) access for patients with cardiac implantable electronic devices (CIEDs) as well as the performance of magnetic resonance (MR)-conditional leads when undergoing MRI. Methods and results: Patients either with an MR-conditional pacemaker or implantable defibrillator (ICD) system or with at least a component (device or one or more leads) from an MR-conditional system, were asked to fill in a questionnaire when they were referred to a MR scan. The rate of prescription, denial, or execution of MR examinations was evaluated in a 1-year follow-up visit. In total, 555 patients [median age (interquartile range) 72.2 (62.2-78.6); 72% male] were enrolled, 49% (270) with a pacemaker, 51% (285) with an ICD system. Five-hundred and ten patients completed the follow-up period. A total of 37 MRI referrals were reported in 35 patients, with a consequent event rate of 7.0/100 patient-years (CI, 4.9-9.7). Fourteen were denied, while 23 [66%; (CI, 48-81%)] were performed. The number of patients with MR referrals was not statistically different between pacemaker and ICD groups (21 vs. 14; P = 0.178). The rate of scans performed was higher in the pacemaker subjects (19/23 vs. 4/14, P = 0.003), while it was similar between patients with or without a complete MR-conditional system (19/30 vs. 4/7, P = 0.606). Conclusion: In this study, we reported a 7.0/100 patient-year's event rate of MR prescriptions in CIED patients. Many examinations were denied, despite MR-conditional systems, especially in ICD patients. Regulatory and cultural changes are needed to allow wider access to MR imaging in CIED patients with MR-conditional systems.

Minimally invasive implantation of the myopore sutureless myocardial pacing lead.

Cardiac resynchronization therapy improves symptoms and survival of patients with congestive heart failure. Usually, the transvenous placement of the left ventricular lead is feasible, but in case of anatomic abnormalities of the coronary sinus, an unintended left phrenic nerve stimulation, a dislodgement of the percutaneous electrode, or a loss of capture of the electrode, surgical treatment should be considered. From January 2010 to September 2011, 15 patients underwent surgical implantation of the left ventricular lead after failure of transvenous placement. The MyoPore sutureless myocardial pacing lead (MSMPL) was implanted through a left minithoracotomy (~5 cm) under selective right lung ventilation. Time of surgery was 38.5 ± 3.0 minutes, and no surgical complications or early deaths are reported so far. After 10.7 ± 8.3 months of follow-up, no cases of late mortality, dislodgement, or loss of capture of the electrode are described. The use of the MSMPL is not novel, although the association with a minimally invasive approach may represent an alternative for a high-risk population. The screw-in of the lead ensures low impedance and threshold of stimulation (1.1 ± 0.6 V at 0.5 milliseconds) both in early and medium terms. In conclusion, in case of failure of the transvenous approach, the MSMPL may be easily implanted through a left minithoracotomy, and the results are noteworthy.

Efficacy of levetiracetam in the treatment of drug-resistant Rett syndrome.

Rett syndrome (RTT) is a progressive neurological disorder characterized by a wide spectrum of phenotypes. Epilepsy is reported to occur in 50-90% of patients with RTT; some develop medically refractory epilepsy. The aim of this study is to investigate the efficacy of levetiracetam (LEV) in drug-resistant patients with RTT. This prospective, pragmatic, open-label study consisted of an 8-week baseline period and a 6-month evaluation period. Efficacy variable was the mean frequency of monthly seizures before, and after 3 and 6 months of treatment with LEV. Eight female patients, aged 7.5-19 years (M12.8+/-5) entered the study. Mean age at epilepsy onset was 25.8+/-14.1 months. All patients showed MeCP2 mutation. Patients had been treated with a mean of 3.4 AEDs (2-7) before LEV. The mean LEV dose was 44.84+/-18.02mg/kg/day. The mean monthly seizure frequency for all types of seizures during the baseline period was 21.3+/-8.1 (range 10-35); after 3 months it was 3.3+/-4.1 (range 0-9) and after 6 months of LEV treatment it was 1.5+/-2 (range 0-4), p<0.0001. The mean follow-up period was 20.2+/-13 months. Mild sleepiness occurred in two patients, one reported intermittent agitation. Levetiracetam appeared effective in our series of drug-resistant RTT patients. All reported a reduction in seizure frequency and consequently a better quality of life.