Suggestive Effects on the Diameter of Coronary Arteries (SUGO-KO)

The present study is a randomized controlled double-blind single center study in order to investigate the effects of verbal suggestions ('vasodilatation') in combination with either a placebo-intervention (sodium chloride 0.9%) or an underdosed vasodilating medication (nitroglycerine) on the diameter of coronary arteries. 60 patients with a clinical indication to undergo a coronary angiogram were recruited in the German Heart Centre Munich. Patients with acute myocardial events and the necessity for coronary intervention were excluded from the study. Patients were randomized into one of four arms of the two experiments:

Experiment A: Intracoronary (i.c.) placebo-infusion together with a standardized verbal suggestion of coronary vasodilation vs. i.c. placebo-infusion without verbal suggestion.

Experiment B: i.c. infusion of a very low dosed nitroglycerin together with a standardized verbal suggestion of coronary vasodilation vs. i.c. nitroglycerine infusion without verbal suggestion.

To our best knowledge this study is the first to investigate the modulating effects of verbal suggestions going along with medical interventions on the diameter of coronary arteries during heart catheterization.