Issue Highlights

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HomeCirculationVol. 113, No. 21Issue Highlights Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBIssue Highlights Originally published30 May 2006https://doi.org/10.1161/circ.113.21.2473Circulation. 2006;113:2473IMPACT OF TRANSFORMING GROWTH FACTOR-β1 ON ATRIOVENTRICULAR NODE CONDUCTION MODIFICATION BY INJECTED AUTOLOGOUS FIBROBLASTS IN THE CANINE HEART, by Bunch et al.Pharmacological treatment of atrial fibrillation using antiarrhythmic agents or ventricular rate control is challenging because of variable success and medication side effects. Catheter ablation also is not 100% successful and carries the risk of procedural complications. In this issue of Circulation, Bunch and colleagues describe a technique of percutaneously injecting cultured fibroblasts from skin biopsies to modulate atrioventricular (AV) nodal conduction and rate control in a canine model. Using electroanatomic mapping and intracardiac echocardiography to guide delivery, they injected fibroblasts (with or without transforming growth factor-β1) through a NOGA catheter at several AV nodal input regions. Regulation of AV nodal conduction and ventricular rate reduction during induced atrial fibrillation was observed and was more pronounced in dogs receiving transforming growth factor-β1–treated fibroblast injections. There were no major complications or long-term high-grade AV block. Local cell delivery may eventually be a potential therapeutic option, perhaps combined with medication and/or device therapy to modulate ventricular rate control during atrial arrhythmias. See p 2485 (and editorial on p 2474).ENHANCED VENTRICULAR UNTWISTING DURING EXERCISE: A MECHANISTIC MANIFESTATION OF ELASTIC RECOIL DESCRIBED BY DOPPLER TISSUE IMAGING, by Notomi et al.Classical concepts of myocardial function learned by all cardiologists center around pressure-volume relationships in the right and left ventricles. It is important to realize, however, that the sequence and pattern of contraction of the 2 ventricles is different: The right ventricle contracts more like a bellows, but the left ventricle undergoes a complex cycle of twisting and untwisting in systole and diastole. Notomi et al provide a detailed analysis of left ventricular (LV) untwisting both at rest and during exercise using Doppler tissue imaging. Although healthy volunteers enhance the rate of untwisting during exercise, thus increasing the diastolic intraventricular pressure gradient (facilitating LV “suction”), patients with hypertrophic cardiomyopathy have a blunted untwisting response to exercise. The new insights into the dynamic relationship between LV systolic and diastolic function described in this paper offer new tools for evaluating diastolic LV function in a variety of cardiovascular disease states and potentially monitoring the response to therapy. See p 2524.PERCUTANEOUS TREATMENT WITH DRUG-ELUTING STENT IMPLANTATION VERSUS BYPASS SURGERY FOR UNPROTECTED LEFT MAIN STENOSIS: A SINGLE-CENTER EXPERIENCE, by Chieffo et al.Coronary artery bypass grafting (CABG) is the preferred revascularization strategy for left main coronary artery (LMCA) disease. Improvements in results with percutaneous coronary intervention (PCI) with drug-eluting stents (DES) have led interventional cardiologists to perform unprotected LMCA procedures. Clinical trial evidence supporting such an approach is lacking, however. In this issue of Circulation, Chieffo et al report the single-center retrospective experience in patients with LMCA stenosis treated with PCI and DES (n=107) or CABG (n=142). At 1 year, there was no difference in the degree of protection against death, stroke, myocardial infarction, and revascularization between PCI with DES and CABG for LMCA disease. These results support the need for randomized trials with longer clinical follow-up to define optimal revascularization strategies for LMCA disease. See p 2542.Visit http://circ.ahajournals.org:Images in Cardiovascular MedicineUntreated 37-Year-Old Homozygous Familial Hypercholesterolemic Smoker. See p e777.Near Sudden Death From Cardiac Lipoma in an Adolescent. See p e778.Left Ventricular Pseudoaneurysm: A Late Complication of Low-Energy DC Ablation. See p e780. Download figureDownload PowerPointCorrespondenceSee p e782. Previous Back to top Next FiguresReferencesRelatedDetails May 30, 2006Vol 113, Issue 21 Advertisement Article InformationMetrics https://doi.org/10.1161/circ.113.21.2473 Originally publishedMay 30, 2006 PDF download Advertisement