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Purpose

Idiopathic junctional ectopic tachycardia (JET) is typically refractory to antiarrhythmic agents. Catheter ablation for JET is feasible but is associated with high risk of unintended atrioventricular (AV) block. There is limited data on the appropriate procedural technique and clinical outcomes with catheter ablation for idiopathic JET in adults.

Methods

This is a multicenter, retrospective study of all adult patients (age?≥?18 years) who underwent catheter ablation for idiopathic JET. Patient, procedural characteristics, and long-term outcomes were evaluated.

Results

Fifteen patients [radiofrequency ablation (RF)?=?14 and cryoablation?=?1) were treated with catheter ablation. The median age was 58 years with 67% males. All patients underwent mapping of the right atrium and the aortic cusps prior to energy delivery. The location of earliest activation in relation to the atrioventricular (AV) node was postero-superior in 73% (11/15), posterior in 13% (2/15), and superior in 13% (2/15) respectively. Acute success was 100%. Arrhythmia recurrence occurred in 53% (8/15) all of whom underwent a repeat ablation. High-grade AV block requiring permanent pacemaker occurred in 20% (3/15). At 12-month follow-up in the redo-ablation group, 37.5% (3/8) had recurrence of the arrhythmia two of which underwent a third ablation procedure.

Conclusion

Catheter ablation of idiopathic JET in adults is associated with a high rate of recurrence requiring multiple procedures and high risk of AV block requiring a permanent pacemaker. Mapping and ablation of the non-coronary cusp can be considered as the arrhythmia was controlled in 3 patients with no inadvertent AV block.

  相似文献   
94.
Even if un to improve long-term prognosis, balloon aortic valvuloplasty (BAV) may be useful in selected patients with symptomatic severe aortic stenosis either as a bridge to surgical or transcatheter valve replacement (aortic valve replacement [AVR] or transcatheter aortic valve implantation [TAVI]) or as a triage strategy for patients with uncertain indications. International guidelines recommend BAV as: a “bridge” to AVR/TAVI, a “trial” in patients with undetermined symptoms, or a “bridge-to-decision” in case of comorbidities. However, in clinical practice, BAV is also used as a palliative measure to improve hemodynamics and quality of life in many patients who are excluded from AVR/TAVI. Finally, BAV is often performed during TAVI to facilitate prosthesis delivery, optimize frame expansion, or for bioprosthetic valve fracture in selected valve-in-valve procedures. Technical innovations, which allow for a mini-invasive approach via transradial access and pacing delivered through the wire, have led to a decrease in complications over time. This review focuses on contemporary BAV with a specific emphasis on new indications, innovative techniques, and specific complex patient subgroups.  相似文献   
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Background and AimsOlder patients with metastatic pancreatic adenocarcinoma (MPDAC) are under-represented in clinical trials.MethodsOur single-center, retrospective study enrolled MPDAC patients ≥ 70 treated with chemotherapyResults105 patients were divided in groups based on the received treatments: 44 gemcitabine or capecitabine monotherapy (A), 34 nabpaclitaxel-gemcitabine (B) 27 4-drugs combinations (gemcitabine, cisplatin, capecitabine plus either nab-paclitaxel or epirubicin or docetaxel) (C). Group A: median age was 78 (70–87) and Karnofsky performance status (KPS) ≥80 was found in 84% of patients; Group B: median age 77 (71–84) and KPS ≥ 80 in 88% of patients; Group C: median age 73 (70–78) and KPS ≥ 80 in 93% of patients. Median OS was 7.9, 11.7 and 14.2 months in group A, B and C respectively; 1 and 2-year OS were 27% and 8% in group A; 44% and 5% in group B; 52% and 22% in group C. When lung metastatic only patients were excluded, patients <75 and ≥ 75 had similar OS in group A (6.4 vs 5.6 months) and in group B (12.3 vs 11.1 months). In group B grade 3 thrombocytopenia, fatigue and peripheral neuropathy were more frequent in patients ≥ 75.ConclusionsIn older patients, combination chemotherapy shows acceptable feasibility and promising efficacy.  相似文献   
97.
Women exhibit less burden of anatomic obstructive coronary atherosclerotic disease as compared with men of the same age, but contradictorily show similar or higher cardiovascular mortality rates. The higher prevalence of nonexertional cardiac symptoms and nonobstructive coronary atherosclerotic disease in women may lead to lack of recognition and appropriate management, resulting in undertesting and undertreatment. Leaders in women’s health from the American College of Cardiology’s Cardiovascular Disease in Women Committee present novel imaging cases that may provoke thought regarding the broad clinical spectrum of myocardial infarction and ischemia with nonobstructive coronary arteries in women. These unique imaging approaches are based on the concept of targeting sex-specific differences in acute and stable ischemic heart disease.  相似文献   
98.
Entry of herpes simplex virus (HSV) 1 into cells requires the interaction of HSV gD with herpesvirus entry mediator or nectin1 receptors, and fusion with cell membrane mediated by the fusion glycoproteins gB, gH, and gL. We report that the gD ectodomain in soluble form (amino acids 1-305) was sufficient to rescue the infectivity of a gD-null HSV mutant, indicating that gD does not need to be anchored to the virion envelope to mediate entry. Entry mediated by soluble gD required, in addition to the receptor-binding sites contained within residues 1-250, a discrete downstream portion (amino acids 261-305), located proximal to the transmembrane segment in full-length gD. We named it as profusion domain. The pro-fusion domain was required for entry mediated by virion-bound gD, because its substitution with the corresponding region of CD8 failed to complement the infectivity of gD(-/+) HSV. Furthermore, a receptor-negative gD (gD(Delta6-259)) inhibited virus infectivity when coexpressed with wild-type gD; i.e., it acted as a dominant-negative gD mutant. The pro-fusion domain is proline-rich, which is characteristic of regions involved in protein-protein interactions. P291L-P292A substitutions diminished the gD capacity to complement gD(-/+) HSV infectivity. We propose that gD forms a tripartite complex with its receptor and, by way of the proline-rich pro-fusion domain, with the fusion glycoproteins, or with one of them. The tripartite complex would serve to recruit/activate the fusion glycoproteins and bring them from a fusion-inactive to a fusion-active state, such that they execute fusion of the virion envelope with cell membrane.  相似文献   
99.
In primary systemic amyloidosis, small numbers of bone marrow plasma cells secrete monoclonal light chains that form extracellular fibrils (amyloid) in various organs. Evidence limited to a few cases suggests that rare clonal elements can also be found in the peripheral blood (PB), and this may be relevant in PB stem cell autotransplantation. Since up to 40% of amyloid clones do not synthesize heavy chains, in order to detect tumor cells with high specificity and sensitivity we developed a seminested allele-specific oligonucleotide polymerase chain reaction for tumor light chains. Clone-related sequences were detected in DNA and/or cDNA from the PB cells of eight of 10 patients at diagnosis and from apheretic collections of three of four cases undergoing PB progenitor autotransplantation. Since there are experimental data suggesting that circulating tumor cells may be involved in the growth of the amyloidogenic clone and may be chemoresistant, these findings are relevant to the use of leukapheresis purging strategies for PB progenitor autotransplantation in amyloidosis.  相似文献   
100.
Previous binding and contractility studies indicate that oxytocin (OT) receptors are present in rabbit epididymis. To investigate the effect of changing endocrine milieu on OT responsiveness, we induced hypogonadism (hypo) in rabbits with a single administration of a long-acting GnRH analog, triptorelin, and we replaced hypogonadal rabbits with different sex steroids. After 2 months from triptorelin administration, testosterone (T) plasma levels were decreased and OT responsiveness abolished. Administration of T to hypo rabbits restored T plasma levels but not OT sensitivity. Because Western blot analysis indicated that both estrogen receptors and aromatase are expressed in the epididymis, we treated hypo rabbits with estradiol valerate (E2v). E2v not only completely restored OT responsiveness but also even amplified it. Accordingly, Northern and Western blot analysis indicated that both OT receptor gene and protein were strongly induced by E2v but not by T. Surprisingly, also the class I estrogen receptor antagonist, tamoxifen restored OT sensitivity in hypo rabbits. To verify whether endogenous estradiol is involved in the regulation of OT receptor responsiveness, we treated intact rabbits with an aromatase inhibitor, letrozole. Blocking aromatase activity almost completely abolished OT sensitivity. These findings suggest a new function of estrogens in the male: regulation of OT responsiveness in epididymis.  相似文献   
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