Therapeutic safety of high myocardial expression levels of the molecular inotrope S100A1 in a preclinical heart failure model.

Low levels of the molecular inotrope S100A1 are sufficient to rescue post-ischemic heart failure (HF). As a prerequisite to clinical application and to determine the safety of myocardial S100A1 DNA-based therapy, we investigated the effects of high myocardial S100A1 expression levels on the cardiac contractile function and occurrence of arrhythmia in a preclinical large animal HF model. At 2 weeks after myocardial infarction domestic pigs presented significant left ventricular (LV) contractile dysfunction. Retrograde application of AAV6-S100A1 (1.5 × 10(13) tvp) via the anterior cardiac vein (ACV) resulted in high-level myocardial S100A1 protein peak expression of up to 95-fold above control. At 14 weeks, pigs with high-level myocardial S100A1 protein overexpression did not show abnormalities in the electrocardiogram. Electrophysiological right ventricular stimulation ruled out an increased susceptibility to monomorphic ventricular arrhythmia. High-level S100A1 protein overexpression in the LV myocardium resulted in a significant increase in LV ejection fraction (LVEF), albeit to a lesser extent than previously reported with low S100A1 protein overexpression. Cardiac remodeling was, however, equally reversed. High myocardial S100A1 protein overexpression neither increases the occurrence of cardiac arrhythmia nor causes detrimental effects on myocardial contractile function in vivo. In contrast, this study demonstrates a broad therapeutic range of S100A1 gene therapy in post-ischemic HF using a preclinical large animal model.

[Renal replacement therapy for refractory heart failure]. / Nierenersatzverfahren bei therapierefraktärer Herzinsuffizienz.

After broad cardiological and nephrological evaluation and consideration of optimal conservative options according to national and international guidelines, renal replacement therapy might be helpful in patients with refractory heart failure even if they are not dialysis-dependent. This is even more important as renal failure is a strong predictor for mortality in patients with severe congestive heart failure (CHF) and CHF is one of the fastest growing morbidities in western countries. Although peritoneal dialysis (PD) is frequently used in patients with CHF its role remains unclear. Acute chronic volume overload in refractory CHF is still an unresolved clinical problem. In patients with acute heart and renal failure with need of management in an intensive care unit, extracorporeal ultrafiltration or a dialysis modality should be preferred. In patients with chronic refractory CHF, volume overload and renal failure, peritoneal dialysis should be the therapy of choice. Due to the limited data available, treatment and outcome parameters should be recorded in the registry of the German Society of Nephrology (http://www.herz-niere.de).