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Updated: Aug 20, 2026

Cardiac Catheterization in Mice to Measure the Pressure Volume Relationship: Investigating the Bowditch Effect
Published on: June 14, 2015
[Effect of vasoactive and coronary drugs on orthostasis in patients with constant-frequency cardiac pacemakers]
Abstract:
It is reported on a group of 31 patients with pacemakers who were exposed to an orthostasis load without additional therapy as well as after an administration of nitrangin, euphyllin, rocornal and ergocomb. The lacking regulation of frequency in these patients can only limitedly be compensated by a volume regulation. Thus the simple standing experiment is already a considerable stress for these patients. Single applications of nitrangin and ergocomb led to an additional orthostatic decrease of blood pressure. This is particularly characterized after application of nitragin and also accompanied by subjective appearances up to the collapse. In the not doubted necessity to treat patients with pacemakers also conserning the coronary blood supply it seems important to take into consideration an additional iatrogenic disturbance of the orthostatic regulation.
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