Systematic review of biological therapies for atrial fibrillation.

Biological therapies that increase or suppress the expression of transcripts underlying atrial fibrillation (AF) progression are increasingly being explored to create novel treatment paradigms beyond simply suppressing or destroying tissue. To date, there has been no systematic overview of the preclinical evidence exploring manipulation of fundamental biological principles in the treatment of AF. As such, the objective of this study was to establish the effect of biological approaches used in the treatment of AF within large and small animals. We performed a systematic search using predefined terms, which yielded 25 studies. We determined the effect of biological approaches on primary efficacy outcomes and assessed the quality of included studies or possible bias in the treatment of AF. Compared with non-transduced or transduced controls, biological therapies reduced AF inducibility (85% less AF; odds ratio 0.15; 95% confidence interval [CI] 0.07-0.35; P < .01) and atrial scar burden (6.7% smaller scars; 95% CI 4.2-9.2; P < .01) or increased number of days in sinus rhythm (6.4 more days in sinus rhythm; 95% CI 5.83-6.97; P < .01). Similar effects were seen in both large and small animals, while a minor tendency to higher risk of bias was observed in small animal studies. In conclusion, treatment with any biological therapy significantly improved AF in preclinical animal models compared with controls. Although biological therapies target markedly different fundamental mechanisms, we observed a consistent difference in their effect on AF outcomes.

Nanoengineered Electroconductive Collagen-Based Cardiac Patch for Infarcted Myocardium Repair.

We have prepared and tested in vivo a novel nanoengineered hybrid electroconductive cardiac patch for treating the infarcted myocardium. Of the prepared and tested patches, only those containing spherical nanogold were able to increase connexin-43 expression in neonatal rat cardiomyocytes cultured under electrical stimulation. In vivo data indicated that only nano-gold-containing patches were able to recover cardiac function. Histological analysis also revealed that connexin-43 levels and blood vessel density were increased, while the scar size was reduced for animals that received the nanogold patch. Thus, our study indicates that the incorporation of electroconductive properties into a collagen-based cardiac patch can improve its therapeutic potential for treating myocardial infarction.

Remote magnetic navigation-assisted catheter ablation enhances catheter stability and ablation success with lower catheter temperatures.

BACKGROUND: It has been suggested that remote magnetic navigation (RMN) may provide enhanced catheter stability and substrate contact to aid in ablation. To date, no study has examined this claim. Accordingly, we compared the characteristics of the successful ablation of atrioventricular reentry tachycardia (AVNRT) using RMN with a matched population ablated using a conventional (CON) manual approach. METHODS: Sixteen patients who underwent RMN-assisted ablation of typical AVNRT were matched with 16 patients who had a CON-AVNRT ablation. RESULTS: All patients had successful slow pathway modification without complication. The mean catheter temperature achieved with the successful ablation was significantly lower with RMN than with CON (42 +/- 7 degrees C vs 47 +/- 3 degrees C, P