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Abstract: Introduction: Catheter ablation for idiopathic ventricular arrhythmia is well established but epicardial origin, proximity to coronary arteries, and limited accessibility may complicate ablation from the venous system in particular from the great cardiac vein (GCV). Methods: Between April 2009 and October 2010 14 patients (56±15years; 9 male) out of a total group of 117 patients with idiopathic outflow tract tachycardias were included undergoing ablation for idiopathic VT or premature ventricular contractions (PVC) originating from GCV. All patients in whom the PVC arose from the GCV were subject to the study. In these patients angiography of the left coronary system was performed with the ablation catheter at the site of earliest activation. Results: Successful ablation was performed in 6/14 (43%) and long-term success was achieved in 5/14 (36%) patients. In 4/14 patients (28.6%) ablation was not performed. In another 4 patients (26.7%), ablation did not abolish the PVC/VT. In the majority, the anatomical proximity to the left coronary system prohibited effective RF application. In 3 patients RF application resulted in a coronary spasm with complete regression as revealed in repeat coronary angiography. Conclusion: A relevant proportion idiopathic VT/PVC can safely be ablated from the GCV without significant permanent coronary artery stenosis after RF application. Our data furthermore demonstrate that damage to the coronary artery system is likely to be transient. [Copyright &y& Elsevier]

Background Long-term clinical and molecular remissions in patients with follicular lymphoma (FL) following high-dose therapy (HDT) and autologous stem cell transplantation (ASCT) have been evaluated in only a few studies. Results are especially limited for second-line HDT with BEAM (BCNU, etoposide, cytarabine and melphalan). Patients and methods Sixty patients with FL received ASCT in our institution (18 first-line with total body irradiation and cyclophosphamide, 34 second-line with BEAM and 8 ≥third-line with BEAM). In the case of long-term remission (>6 years; N = 17), peripheral blood was tested for minimal residual disease by t(14;18)- and IGH-PCR. Results Ten-year overall survival, progression-free survival and freedom from progression (FFP) after first-line ASCT were 79%, 57% and 64% after second-line ASCT 41%, 35% and 42%, respectively. Prognostic factors for FFP were treatment line and FLIPI (Follicular Lymphoma International Prognostic Index). Ten-year FFP for second-line ASCT and low-risk FLIPI was 57%, intermediate risk 37% and high risk 33%. No relapses occurred after 6 years following ASCT. Sixteen patients developed sustained long-term clinical and molecular remissions of up to 17.5 years. Conclusion Sustained long-term clinical and molecular remissions can be achieved following ASCT, including HDT with BEAM in second line. [ABSTRACT FROM PUBLISHER]

Background: Electrophysiologic characteristics, mapping strategies, and acute success rates of radiofrequency catheter ablation of atriofascicular accessory pathways are well described. However, data on long-term prognosis and predictors for freedom from arrhythmias are lacking.Objective: To report our 20-year single-center experience on ablation of atriofascicular fibers.Method: Between 1992 and 2010, 34 patients with atriofascicular accessory pathways underwent catheter ablation at our institution because of symptomatic antidromic atrioventricular reentrant tachycardias. Radiofrequency procedures were retrospectively analyzed, and patients were followed for recurrences of tachyarrhythmias. Electrocardiograms (before and after ablation and at follow-up) were analyzed for each patient.Results: Successful catheter ablation of the atriofascicular fiber was achieved in 23 (68%) patients. Mechanical block during mapping occurred in 3 (9%) patients, and in 2 of them ablation was performed at the site of mechanical block. Mere modification of conduction properties of the pathway without complete block was achieved in 5 patients (15%). Fast pathway ablation was performed in 2 (6%) of the patients ablated in the early 1990s. During follow-up of 9.3 ± 5.5 years, 24 patients (71%) remained free of tachyarrhythmias, 7 reported significant improvement, and 3 (9%) had no change in symptoms after ablation. Long-term success was identical between patients from the first (1992-1999) and second (2000-2010) decade (12 of 17 [71%] vs 12 of 17 [71%]). It was 87% in those with complete block of the atriofascicular fiber while all patients with mechanical block during mapping reported recurrences. Fast pathway ablation was complicated by complete atrioventricular block in 1 patient, who required pacemaker implantation 18 years after ablation owing to loss of conduction properties of the atriofascicular fiber over the years. On analyzing patients with preexcitation before ablation (n = 16; 47%), we found that the PR interval after ablation was significantly longer only in those without recurrence (162 ± 21 ms vs 134 ± 21 ms; P = .042). None of the other analyzed electrocardiographic parameters, including PR, QRS duration, and preexcitation, had prognostic impact.Conclusion: Acute success of complete ablation of atriofascicular pathways is associated with excellent long-term success (87%). Mere modification of conduction properties of atriofascicular fibers or ablation at the sites of mechanical block are less promising end points of ablation with high recurrence rates. Technical innovations during decades may not further improve long-term outcome in these patients. [ABSTRACT FROM AUTHOR]

Background: Molecular remodeling in heart failure includes slowing of repolarization, leading to proarrhythmia.Objective: To evaluate the effects of Na(+)/Ca(2+) exchanger (NCX) inhibition on repolarization as a novel antiarrhythmic concept in chronic heart failure (CHF).Methods and Results: CHF was induced by rapid ventricular pacing in rabbits. Left ventricular function was assessed by echocardiography. Monophasic action potentials (MAPs) showed a prolongation of repolarization in CHF after atrioventricular block and stimulation at different cycle lengths. Sotalol (100 μM, n = 13) or veratridine (0.5 μM; n = 15) resulted in a further significant increase in the MAP duration. CHF was associated with an increased dispersion of repolarization, as compared with sotalol-treated (+22 ± 7 ms; P < .05) and veratridine-treated (+20 ± 6 ms; P < .05) sham hearts. In the presence of a low potassium concentration, sotalol and veratridine reproducibly induced early afterdepolarizations (EADs) and polymorphic ventricular tachyarrhythmias (VTs). SEA0400 (1 μM), a pharmacological inhibitor of NCX, significantly shortened the MAP duration (P < .01) and reduced dispersion (P < .05). It suppressed EAD in 6 of 13 sotalol-treated failing hearts and in 9 of 10 veratridine-treated failing hearts, leading to a reduction in VT (60% in sotalol-treated failing hearts and 83% in veratridine-treated failing hearts). Simulations using a mathematical model showed a reduction in the action potential duration and the number of EADs by the NCX block in all subgroups.Conclusions: In an experimental model of CHF, the acute inhibition of NCX (1) reduces the MAP duration, (2) decreases dispersion of repolarization, and (3) suppresses EAD and VT. Our observations indicate for the first time that pharmacological NCX inhibition increases repolarization reserve and protects against VTs in heart failure. [ABSTRACT FROM AUTHOR]

BACKGROUND: In nonfailing myocardium, beta(3)-adrenergic signaling causes a decrease in contractility via endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO) release. This study investigates the hypothesis that beta(3)-adrenergic signaling undergoes alterations in failing myocardium. METHODS: We compared eNOS- and beta(3)-adrenoceptor expression using Western blot analysis in human nonfailing myocardium versus failing myocardium. With the use of immunohistochemistry, we investigated the distribution of the beta(3)-adrenoceptor protein and eNOS translocation and phosphorylation under basal conditions. beta(3)-adrenergic, eNOS activation, and inotropy were measured in failing myocardium using BRL37344 (BRL, a beta(3)-adrenoceptor agonist). RESULTS: beta(3)-adrenoceptor expression was increased in failing myocardium. Under basal conditions, Akt- and eNOS(Ser1177) phosphorylation were reduced in failing myocardium. During stimulation with BRL in failing myocardium, a further dephosphorylation of eNOS(Ser1177) and Akt was observed, whereas eNOS(Ser114) phosphorylation was increased. These results suggest a deactivation of eNOS via beta(3)-adrenergic stimulation. Nevertheless, BRL decreased contractility in failing myocardium, but this effect was not observed in the presence of the NO blocker L-NMA. In failing myocardium, the beta(3)-adrenoceptor was predominantly expressed in endothelial cells. In the cardiomyocytes, the beta(3)-adrenoceptor was mainly located at the intercalated disks. CONCLUSION: In failing cardiomyocytes, beta(3)-adrenergic stimulation seems to deactivate rather than activate eNOS. At the same time, beta(3)-adrenergic stimulation induced a NO-dependent negative inotropic effect. Because beta(3)-adrenoceptors are expressed mainly in the endothelium in failing myocardium, our observations suggest a paracrine-negative inotropic effect via NO liberation from the cardiac endothelial cells. [ABSTRACT FROM AUTHOR]

Background: Long QT syndrome (LQTS) is associated with sudden cardiac death resulting from torsades de pointes (TdP), which are triggered by early afterdepolarizations (EADs). The cardiac Na(+)/Ca(2+) exchanger (NCX) has been suggested to work as a trigger for EADs.Objective: The purpose of this study was to test the hypothesis that inhibition of NCX with a newly developed selective NCX inhibitor (SEA0400) reduces TdP.Methods and Results: In 34 Langendorff-perfused rabbit hearts, the I(Kr)-blocker sotalol (100 microM; n = 18) as well as veratridine (0.5 microM; n = 16), an inhibitor of sodium channel inactivation, led to a significant increase in monophasic action potential (MAP) duration thereby mimicking LQTS2 and LQTS3. In bradycardic hearts, recordings of eight MAPs demonstrated an increased dispersion of repolarization (sotalol: 67%; veratridine: 89%; P <.05). After lowering of potassium concentration, sotalol (56%) and veratridine (63%) induced TdP. Perfusion with SEA0400 (1 microM) suppressed EADs in 15 of 16 sotalol hearts and in seven of 13 veratridine hearts. SEA0400 significantly shortened MAP duration and reduced dispersion of repolarization in both groups (P <.05). This reduced TdP incidence in the sotalol group (100%) and in the veratridine group (77%). To investigate the effects of NCX inhibition on the cellular level, we used a computer model of the rabbit ventricular myocyte. I(Na) and I(Kr) were modified to mimic the effects of veratridine and sotalol, respectively. Consistent with our in vitro experiments, reduction of NCX activity accelerated repolarization of the cellular action potential and prevented EADs.Conclusion: In an intact rabbit heart model of LQT2 and LQT3 as well as in a computer model of the rabbit cardiac myocyte, inhibition of NCX is effective in preventing TdP due to a suppression of EADs, a reversion of action potential prolongation, and a reduction of dispersion of repolarization. Our observations suggest a therapeutic benefit of selective NCX inhibition in LQTS. [ABSTRACT FROM AUTHOR]

Background: Pattern and outcome of disease recurrence after autologous stem-cell transplantation (autoSCT) for follicular lymphoma (FL) is not well known. [ABSTRACT FROM PUBLISHER]

The European Society for Medical Oncology (ESMO) consensus conference on mature B-cell lymphomas and chronic lymphocytic leukaemia (CLL) was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (i) the elderly patient, (ii) prognostic factors suitable for clinical use and (iii) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address four clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the four questions assigned to their group. These recommendations were then presented to the entire panel and a consensus was reached. This manuscript presents recommendations dedicated to the second area of interest, i.e. prognostic factors suitable for clinical use. The four topics [i.e. interim positron emission tomography (PET), TP53 mutations, cell of origin (COO) and minimal residual disease (MRD)] were primarily chosen because of the bulk of available data together with the lack of clear guidance regarding their use in clinical practice and within clinical trials. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript. The panel acknowledged that detection of TP53 inactivation by deletion or mutation in CLL should be implemented in clinical practice (level of evidence I, strength of recommendation A). Due to their potentially high prognostic value, at least in some lymphoma entities, implementation of interim PET, COO and MRD was highly recommended in the context of clinical trials. All expert panel members approved this final article. [ABSTRACT FROM AUTHOR]