Quadripolar Left Ventricular Lead in a Patient with CRT-D Does Not Overcome Phrenic Nerve Stimulation

Effective cardiac resynchronization therapy (CRT) requires an accurate atrio-biventricular pacing system. The innovative Quartet lead is a quadripolar, over-the-wire left ventricular lead with four electrodes and has recently been designed to provide more options and greater control in pacing vector selection. A lead with multiple pacing electrodes is a potential alternative to physical adjustment of the lead and may help to overcome high thresholds and phrenic nerve stimulation (PNS).

Gated myocardial perfusion scintigraphy in children with sickle cell anemia: correlation with echocardiography

OBJECTIVES

The heart is one of the organs affected by sickle cell anemia (SCA). This prospective study has aimed to evaluate myocardial perfusion and left ventricle (LV) function in children with SCA by gated myocardial perfusion scintigraphy (G-MPS) and to compare the results with echocardiographic parameters.

METHODS

Forty-three patients with SCA were evaluated by G-MPS and echocardiography. Myocardial perfusion and motion with thickening function were analyzed both visually and quantitatively. End-diastolic (EDV), end-systolic volumes (ESV), ejection fraction (EF), lung-to-heart (L/H) ratio were also calculated.

RESULTS

None of the patients showed stress perfusion impairment in G-MPS. LV dilatation in 15 patients was observed both by G-MPS and echocardiography. EF values were within normal limits. Correlation between EF values calculated by two methods was not statistically significant. However, LV dilatation detected by both methods and EDV-ESV values in G-MPS were correlated to end-diastolic and end-systolic diameters calculated in echocardiography (p<0.05). M-Mode echocardiography revealed higher myocardial performance index (LV-MPI) in patients with LV dilatation. There was also a significant relationship between LV dilatation and frequent blood transfusions (>5/years) and acute chest syndrome (p<0.05).

CONCLUSION

Myocardial perfusion impairment in children with SCA is not frequently observed. Thus, performing the scintigraphy only in patients with cardiac symptoms should be considered. Since EF values of the children with SCA are not deteriorated in early stages, LV-MPI and LV dilatation should be considered as a significant parameter other than EF or perfusion data.

Liver function tests and one year risperidone treatment in children and adolescents

Objective

Risperidone is an atypical antipsychotic agent, despite its many advantages and widespread use, there is increasing attention to the adverse effects associated with long-term exposure to this drug.We aimed to investigate the changes in the liver function tests (LFTs) associated with one year risperidone treatment in children and adolescents.

Methods

One hundred youths who treated with risperidone more than one year were included in the study. For this study, patients’ baseline and follow-up weight and hepatobiliary function tests including alanine aminotransferases(ALT) and aspartat aminotransferases (AST), gamma gluatamyl transerase (GGT), alkaline phosphatase (ALP) and serum bilirubin levels were measured baseline, after the treatment period of six months and one year.

Results

Asymptomatic liver function test abnormalities mostly ALP elevation was found in subjects treated with risperidone. The mean levels of liver enzymes and billuribin of the patients were significantly higher after one year of treatment than the baseline. Also the mean levels of liver enzymes and billuribin of the patients were significantly higher after one year of treatment than the six months. There was significant association between changes in weight, risperidone dose and liver enzymes and billuribin levels.

Conclusions

These findings suggest that risperidone treatment in the long term commonly leads to liver function changes however it rarely may induce a serious hepatic toxicity at therapeutic doses in children and adolescents.

Accuracy of the Polar S810i(TM) Heart Rate Monitor and the Sensewear Pro Armband(TM) to Estimate Energy Expenditure of Indoor Rowing Exercise in Overweight and Obese Individuals

Accurately assessing the energy expenditure (EE) of different types of physical activity is important for exercise prescription in obese individuals. The aim of this study was to examine the accuracy of the Polar S810i Heart Rate Monitor and SenseWear Pro Armband (SWA) for estimating energy expenditure (EE) during indoor rowing versus indirect calorimetry (IC). 43 overweight and obese adults (16 men, 27 women, BMI = 31.2 ± 3.7) participated in the study. Within a week after a maximal incremental test on a rowing ergometer, EE was assessed with Polar S810i, SWA and IC during two different intensities of rowing exercises (at 50% VO2max and 70% VO2max) on a Concept II ergometer. Data were analyzed with Pearson's product moment correlations and repeated measures ANOVA. Post hoc multiple comparisons were performed using the Bonferroni test. Bland-Altman plots were created to assess the agreement between the EE estimates and IC measurements. At 50% VO2max, Polar S810i and SWA significantly overestimated EE by 0.5 ± 0.50 kcal·min(-1) (p < 0.001) and by 0.9 ± 0.92 kcal·min(-1) (p < 0.001), respectively. At 70% VO2max, no significant differences were found between the SWA and IC, and between Polar S810i and IC measurements. Bland-Altman plots showed good agreements between the measured EE and estimates by Polar S810i and SWA at 70% VO2max. At 50% VO2max, there was a poor agreement between SWA and IC measurements. There were high correlations among three methods at both intensities (r = 0.82 to r = 0.95). In conclusion, Polar S810i and SWA showed reasonable concordance with IC for measuring EE of the moderate intensity exercise but not the lower intensity exercise on indoor rowing in the participants of this study. Polar S810i and SWA might be useful to assess EE during indoor rowing for overweight and obese individuals who try to manage their body weight, but it is necessary to develop exercise and population specific algorithms to enhance the accuracy of SWA to estimate energy expenditure during various intensities of physical exercises. Key pointsPolar S810i and SWA when compared to the indirect calorimetry, provide reasonable estimates of energy expenditure on rowing ergometer at the moderate exercise intensity, but not at the low exercise intensity.The monitor of the Concept II Model D rowing ergometer significantly overestimated the energy expenditure during low and moderate intensity exercises. However there was a moderate correlation between EE estimates of this device and indirect calorimetry measurements.

Unusual extraosseous tumoral accumulation of 99mTc-MDP in non-Hodgkin's lymphoma in two cases

The authors describe a rare pattern of soft tissue uptake observed in a (99m)Tc-MDP bone scintigraphy of two patients with the diagnosis of non-Hodgkin's lymphoma. Both patients had abdominal masses and bone scintigraphy revealed unusual (99m)Tc-MDP uptake in the abdominal region. The possible mechanisms of soft tissue uptake of bone seeking agents are discussed.

Non-invasive Indices for the Estimation of the Anaerobic Threshold of Oarsmen

This study compared four common non-invasive indices with an invasive index for determining the anaerobic threshold (AT) in 22 adult male rowers using a Concept2 rowing ergometer. A criterion-standard progressive incremental test (invasive method) measured blood lactate concentrations to determine the 4 mmol/l threshold (La4-AT) and Dmax AT (Dm-AT). This was compared with three indices obtained by analysis of respiratory gases and one that was based on the heart rate (HR) deflection point (HRDP) all of which used the Conconi test (non-invasive methods). In the Conconi test, the HRDP was determined whilst continuously increasing the power output (PO) by 25 W/min and measuring respiratory gases and HR. The La4-AT and Dm-AT values differed slightly with respect to oxygen uptake, PO and HR however, AT values significantly correlated with each other and with the four non-invasive methods. In conclusion, the non-invasive indices were comparable with the invasive index and could, therefore, be used in the assessment of AT during rowing ergometer use. In this population of elite rowers, Conconi threshold (Con-AT), based on the measurement of HRDP tended to be the most adequate way of estimating AT for training regulation purposes.

Protective effect of beta-carotene on methotrexate-induced oxidative liver damage

In this study, the authors aimed to investigate the role of oxidative stress on the hepatic damage caused by methotrexate (MTX) and the possible protective effects of beta-carotene against this damage. The rats were divided into four groups as control, MTX (20 mg/kg ip), beta-carotene (10 mg/kg/day ip) + MTX, and beta-carotene. Histopathologic alterations were evaluated for defining the liver damage. The tissue, malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GP-x) contents and serum aspartate aminotransferase (AST) and alanine aminotranferase (ALT) activities were also examined. Histopathologic damage for each group score findings have been determined as control: 0.66 +/- 0.33; MTX: 7.0 +/- 0.68; beta-carotene + MTX: 3.3 +/- 0.42; and beta-carotene: 0.5 +/- 0.3. In the MTX-treated group, MDA, AST, and ALT values were increased, while SOD and GP-x values were decreased compared with the control group. In the beta-carotene + MTX-treated group, AST and ALT values significantly decreased, while all other parameters were similar to the control group. This study shows that beta-carotene has a protective effect on MTX-induced oxidative hepatic damage. Consequently, it seems that an antioxidant agents like beta-carotene may be useful in decreasing the side effects of chemotherapy.

GRACE risk score as predictor of in-hospital mortality in patients with chest pain

INTRODUCTION

Chest pain and chest discomfort are common problems in the acute care setting. Life-threatening causes of chest pain must be quickly differentiated from other less serious causes. There is a need to stratify risk rapidly in patients presenting to the emergency department (ED) with chest pain. This study evaluates the relationship between the GRACE risk score (GRS) and in-hospital mortality in patients presenting to the ED with chest pain of all causes.

METHODS

We conducted a prospective study of a consecutive sample of 1,014 patients with chest pain and chest discomfort presenting to the medical ED of the University Clinic in Giessen, Germany. The GRS was calculated for each patient at admission. Additionally, the reason for admission into the hospital and the diagnosis on discharge or diagnosis of death were recorded. The relative risk between the risk groups was assessed, and the functional dependency between the GRS and observed in-hospital death was analyzed.

RESULTS

A total of 94 patients died during the stay in the hospital, 83 patients with high risk, 9 with medium risk, and 2 with low risk. The risk of in-hospital death was 24.5% for high-risk patients, 2.6% for medium-risk patients, and 0.6% for patients with low risk. The correlation between the GRS and in-hospital mortality is strongly positive (p < 0.01).

CONCLUSION

This study shows that the GRS accurately stratifies risk of intra-hospital mortality in patients presenting to the ED with chest pain and can guide patient triage and management.

Factor seven ativating potease (FSAP) levels during normal pregnancy and in women using oral contraceptives

INTRODUCTION

Factor seven activating protease (FSAP) is a plasma serine protease involved in haemostasis and remodeling processes. We have investigated whether pregnancy or the use of oral contraceptives (OCs) influences circulating FSAP levels. The effect of female sex hormones on FSAP expression in cultured cells was also determined.

MATERIALS AND METHODS

FSAP levels and activity was measured in plasma samples obtained at different gestation stages from healthy pregnant women (n=101), from non-pregnant women, pre-menopausal women who currently use OCs (n=48), and non-pregnant women who did not use OCs (n=69).

RESULTS

In late pregnancy the plasma FSAP antigen (median 2.28 PEU/ml [range 1.11 to 2.62 PEU/ml]; p<0.001 vs control group) and activity (median 2.98 PEU/ml [range 1.05 to 4.24 PEU/ml]; p<0.001 vs control group) was significantly higher compared with levels in non-pregnant women and remained elevated after delivery. Plasma FSAP levels in women using OCs was also significantly elevated compared to the control group. Ex vivo experiments demonstrated enhanced FSAP expression in monocytes isolated from women using OCs. In vitro experiments showed that FSAP mRNA levels were strongly induced by estradiol in monocytes but not in hepatocytes.

CONCLUSIONS

Increased levels of circulating FSAP in pregnancy and in women using OCs indicate that hormonal status critically influences FSAP expression. Hormonal influences could be observed in monocytes in vivo and ex-vivo but not in hepatocytes indicating cell-specific regulation. Future studies designed to investigate the role of FSAP in haemostasis and remodeling processes should consider the role of female sex hormones on FSAP expression.

Insulin stabilizes microvascular endothelial barrier function via phosphatidylinositol 3-kinase/Akt-mediated Rac1 activation

OBJECTIVE

Insulin is a key regulator of metabolism, but it also confers protective effects on the cardiovascular system. Here, we analyze the mechanism by which insulin stabilizes endothelial barrier function.

METHODS AND RESULTS

Insulin reduced basal and antagonized tumor necrosis factor-alpha-induced macromolecule permeability of rat coronary microvascular endothelial monolayers. It also abolished reperfusion-induced vascular leakage in isolated-perfused rat hearts. Insulin induced dephosphorylation of the regulatory myosin light chains, as well as translocation of actin and vascular endothelial (VE)-cadherin to cell borders, indicating a reduction in contractile activation and stabilization of cell adhesion structures. These protective effects were blocked by genistein or Hydroxy-2-naphthalenylmethylphosphonic acid tris acetoxymethyl ester (HNMPA-[AM](3)), a pan-tyrosine-kinase or specific insulin-receptor-kinase inhibitor, respectively. Insulin stimulated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and NO production, and it activated Rac1. Inhibition of PI3K/Akt abrogated Rac1 activation and insulin-induced barrier protection, whereas inhibition of the endothelial nitric oxide synthase/soluble guanylyl cyclase pathway partially inhibited them. Inhibition of Rac1 abrogated the assembly of actin at cell borders. Accordingly, it abolished the protective effect of insulin on barrier function of the cultured endothelial monolayer, as well as the intact coronary system of ischemic-reperfused hearts.

CONCLUSIONS

Insulin stabilizes endothelial barrier via inactivation of the endothelial contractile machinery and enhancement of cell-cell adhesions. These effects are mediated via PI3K/Akt- and NO/cGMP-induced Rac1 activation.

Pneumopericardium and pneumomediastinum as a late complication of defibrillator implantation after coronary artery bypass graft surgery

A 69-year-old male underwent implantation of a cardioverter-defibrillator with cardiac resynchronization therapy (CRT) for symptomatic ventricular tachyarrhythmia (VT) and severe left ventricular (LV) dysfunction with an ejection fraction (EF) of 30 % and dyssynchrony via a left subclavian venous access. Twenty days after the procedure, the patient complained of shortness of breath and was found to have a 30 % apical left pneumothorax on chest X-ray as a not unusual complication of the subclavian venous access. A computed axial tomography of the chest revealed pneumopericardium and associated pneumomediastinum as a complication of the CRT implantation and persisting microscopic pleuro-pericardial fistula as a consequence of previous coronary artery bypass graft surgery (CABG), accidentally diagnosed three years after the procedure. The pneumothorax and pneumopericardium were small and did not require chest tube placement. The patient was treated conservatively and his subsequent course was excellent.

Do gender differences exist in pacemaker implantation?--results of an obligatory external quality control program

AIMS

The aim of the study was to evaluate the effects of patient gender onto primary pacemaker implantation, evaluating the database of the Institute of Quality Assurance Hessen in the federal state of Hessen, Germany.

METHODS AND RESULTS

The database of the obligatory external quality control program for the years 2003-2006 was evaluated retrospectively. In 72 centres, 17 826 patients undergoing stationary primary pacemaker implantation have been registered. Male patients had more AV blocks when compared with women and less sick sinus syndrome and atrial fibrillation with bradycardia. In patients being 80 years and older, men received significantly more dual-chamber devices than women for the indications: AV block and sick sinus syndrome. In women, atrial pacing thresholds were significantly higher and P-wave amplitudes were significantly lower. Women had, independent from age or pacing system implanted, significantly more acute complications than men, with significant differences for pneumothorax and pocket haematoma.

CONCLUSION

This large-scale real-life patient cohort of primary stationary pacemaker implantation showed that gender has an impact onto pacemaker implantation, with less favourable outcomes for women.

Prospective randomized comparison of durability of bidirectional conduction block in the cavotricuspid isthmus in patients after ablation of common atrial flutter using cryothermy and radiofrequency energy: the CRYOTIP study

BACKGROUND

Recent studies have shown that cryoablation and radiofrequency (RF) ablation are comparable with regard to success rates and safety in the treatment of common atrial flutter (AFL). Long-term success requires persistence of bidirectional conduction block (BCB) in the inferior cavotricuspid isthmus (CTI).

OBJECTIVE

The purpose of this study was to determine the persistence of BCB in a prospective randomized multicenter trial of the two ablation techniques.

METHODS

A total of 191 patients were randomized to RF ablation or cryoablation of the CTI using an 8-mm-tip catheter. In all patients, BCB was defined as the ablation end-point. Primary end-point of the study was nonpersistence of achieved BCB and/or ECG-documented relapse of common AFL within 3-month follow-up.

RESULTS

Acute success rates were 91% (83/91) in the RF group and 89% (80/90) in the cryoablation group (P = NS). Invasive follow-up after 3 months with repeated electrophysiologic study was available for 60 patients in the RF group and 64 patients in the cryoablation group. Persistent BCB could be confirmed in 85% of the RF group versus 65.6% of the cryoablation group. The primary end-point was achieved in 15% of the RF group and 34.4% of the cryoablation group (P = .014). As a secondary end-point, pain perception during ablation was significant lower in the cryoablation group (P <.001).

CONCLUSION

Persistence of BCB in patients treated with cryoablation reinvestigated after 3 months is inferior to that patients treated with RF ablation, as evidenced by the higher recurrence rate of common AFL seen in this study.

Beneficial effects of intravenously administered N-3 fatty acids for the prevention of atrial fibrillation after coronary artery bypass surgery: a prospective randomized study

BACKGROUND

Atrial fibrillation (AF) is a common complication after coronary artery bypass grafting operation (CABG). Experimental data have shown antiarrhythmic effects of n-3 polyunsaturated fatty acids (PUFA) on myocardial cells. Orally administered PUFA could significantly reduce the rate of postoperative AF. We assessed the efficacy of PUFA for the prevention of AF after CABG. PUFA were given intravenously to prevent variation in bioavailability.

METHODS AND RESULTS

52 patients were randomized to the interventional group, 50 served as controls. In the control group free fatty acids (100 mg soya oil/kg body weight/day) were infused via perfusion pump, starting on admission to hospital and ending at discharge from intensive care. In the interventional group PUFA were given at a dosage of 100 mg fish oil/kg body weight/day. Primary end point was the postoperative development of AF, documented by surface ECG. Secondary end point was the length of stay in the ICU. The demographic, clinical and surgical characteristics of the patients in the two groups were similar. Postoperative AF occurred in 15 patients (30.6 %) in the control and in 9 (17.3 %) in the PUFA group ( P < 0.05). After CABG, the PUFA patients had to be treated in the ICU for a shorter time than the control patients. No adverse effects were observed.

CONCLUSIONS

Perioperative intravenous infusion of PUFA reduces the incidence of AF after CABG and leads to a shorter stay in the ICU and in hospital. Our data suggest that perioperative intravenous infusion of PUFA should be recommended for patients undergoing CABG.

Reduction of myocardial infarction by postischemic administration of the calpain inhibitor A-705253 in comparison to the Na(+)/H(+) exchange inhibitor Cariporide in isolated perfused rabbit hearts

The calpain inhibitor A-705253 and the Na(+)/H(+)-exchange inhibitor Cariporide were studied in isolated perfused rabbit hearts subjected to 60 min occlusion of the ramus interventricularis of the left coronary artery (below the origin of the first diagonal branch), followed by 120 min of reperfusion. The inhibitors were added to the perfusion fluid solely or in combination at the beginning of reperfusion. Hemodynamic monitoring and biochemical analysis of perfusion fluid from the coronary outflow were performed. Myocardial infarct size and area at risk (transiently not perfused myocardium) were determined from left ventricular slices after a special staining procedure with Evans blue and 2,3,5-triphenyltetrazolium chloride. The infarcted area (dead myocardium) was 72.7+/-4.0% of the area at risk in untreated controls, but was significantly smaller in the presence of the inhibitors. The largest effect was seen with 10(-6) m A-705253, which reduced the infarcted area to 49.2+/-4.1% of the area at risk, corresponding to a reduction of 33.6%. Cariporide at 10(-6) m reduced the infarct size to the same extent. The combination of both inhibitors, however, did not further improve cardioprotection. No statistical difference was observed between the experimental groups in coronary perfusion, left ventricular pressure, heart rate, and in the release of lactate dehydrogenase and creatin kinase from heart muscle.

Clinical and arrhythmic outcomes after implantation of a defibrillator for primary prevention of sudden death in patients with post-myocardial infarction cardiomyopathy: The Survey to Evaluate Arrhythmia Rate in High-risk MI patients (SEARCH-MI)

Aims

To evaluate clinical and arrhythmic outcomes in post-infarction cardiomyopathy patients implanted with a defibrillator (ICD) for primary prevention of sudden death.

Methods and results

The SEARCH-MI registry is a European multi-centre, prospective, observational study enrolling patients after myocardial infarction, chronic left ventricular dysfunction and an ICD implanted for primary prevention of sudden death. Data on 556 patients with at least one recorded follow-up are presented. Survey to Evaluate Arrhythmia Rate in High-risk MI (SEARCH-MI) patients were sicker than those enrolled in MADIT-II with higher New York Heart Association class and left bundle branch block. Total mortality was 10.4%. Close to one-third (30%) of patients experienced episodes of sustained ventricular arrhythmia. One-quarter (23%) received at least one appropriate therapy and 10% inappropriate therapy. Gender (25% males vs. 5% females, P = 0.0009) and history of non-sustained ventricular tachycardia (24% with vs. 18% without P = 0.037) were predictive of appropriate ventricular therapy.

Conclusion

SEARCH-MI represents the current clinical management of post-MI patients with left ventricular dysfunction indicated to defibrillator implant for primary prevention. European routine clinical practice was influenced by landmark trials and guidelines which impacted on the implantation of cardiac resynchronization therapy in over 25% of such patients. Non-sustained ventricular tachycardia identifies subjects with a higher incidence of appropriate ICD therapy.

Prognostic value of heart rate variability after acute myocardial infarction in the era of immediate reperfusion

INTRODUCTION

The incidence and significance of impaired heart rate variability (HRV) after acute myocardial infarction (AMI) have not yet been evaluated in cohorts of patients in whom early reperfusion was systematically attempted. Therefore, HRV was evaluated in 412 unselected patients with AMI (311 men, mean age: 60+/-12 years, anterior AMI in 172 patients) treated with direct coronary angioplasty (PTCA) within 12 hours of symptom onset (mean 3.5+/-2.0 h). Standard deviation of normal RR intervals (SDNN), square root of the mean of the sum of the squares of differences between adjacent RR intervals (RMSSD) and left ventricular ejection fraction (LVEF, mean: 55+/-15%) were measured 11+/-9 days after AMI before discharge. Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers were prescribed at discharge in 81.1% and 70.1% of patients, respectively.

RESULTS

Mean SDNN was 94+/-30 ms (range 14-155). SDNN was <50 ms in 7% of patients. Mean RMSSD was 34+/-32 ms (range 2-234). RMSSD was <15 ms in 21% of patients. Low SDNN (<50 ms) was unrelated to gender, age, infarct location or extension of CHD but was related to low LVEF (p<0.001, logistic regression analysis). During mean follow-up of 4.3+/-3 years, there were 31 deaths; 24 were cardiac. SDNN was higher in long-term survivors (102+/-39 ms) as compared to nonsurvivors (81+/-33 ms, p=0.02) but RMSSD was unrelated to the long-term vital status. Four-year survival of patients with a SDNN <50 ms vs >50 ms was 80% vs 92%, respectively (p<0.001, Kaplan Meier analysis). Low SDNN (odds ratio OR=2.0, p<0.05) but not RMSSD was an independent denominator for long-term mortality as were low LVEF (OR=1.0 decrease in LVEF, p<0.01, proportional hazards model) and age (OR=1.1, p<0.001). Only 3/31 fatalities and 1/24 cardiac deaths were predicted by a SDNN <50 ms and only 5/31 fatalities by a RMSSD <15 ms.

CONCLUSION

The incidence of severely depressed HRV in patients after AMI is low (<10%) in the era of early reperfusion of the infarct vessel using direct PTCA. Mortality in patients with a very low HRV when assessed by SDNN is substantial but the positive predictive value of this parameter is low.

Managed ventricular pacing vs. conventional dual-chamber pacing for elective replacements: the PreFER MVP study: clinical background, rationale, and design

AIMS

Several clinical studies have shown that, in patients with intact atrioventricular (AV) conduction, unnecessary chronic right ventricular (RV) pacing can be detrimental. The managed ventricular pacing (MVP) algorithm is designed to give preference to spontaneous AV conduction, thus minimizing RV pacing. The clinical outcomes of MVP are being studied in several ongoing trials in patients undergoing a first device implantation, but it is unknown to what extent MVP is beneficial in patients with a history of ventricular pacing. The purpose of the Prefer for Elective Replacement MVP (PreFER MVP) study is to assess the superiority of the MVP algorithm to conventional pacemaker and implantable cardioverter-defibrillator programming in terms of freedom from hospitalization for cardiovascular causes in a population of patients exposed to long periods of ventricular pacing.

METHODS AND RESULTS

PreFER MVP is a prospective, 1:1 parallel, randomized (MVP ON/MVP OFF), single-blinded multi-centre trial. The study population consists of patients with more than 40% ventricular pacing documented with their previous device. Approximately, 600 patients will be randomized and followed for at least 24 months. The primary endpoint comprises cardiovascular hospitalization.

CONCLUSION

The PreFER MVP trial is the first large prospective randomized clinical trial evaluating the effect of MVP in patients with a history of RV pacing.