Enoximon-echocardiography. A new diagnostic approach for the detection of viable myocardium comparison to dobutamin-echocardiography.

UNLABELLED

Hypo- or akinetic myocardial regions can be identified as viable myocardium through recruitment of inotropic reserve. Both, dobutamine (D) as well as enoximone (E) mediate their inotropic action via an increase in intracellular c-AMP concentration based on a different action. In 10 patients with documented myocardial infarction either D (5 to 40 micrograms/kg/min, increments of 5 micrograms/kg/min every 3 min) or E (1 to 9 micrograms/kg/min, increments of 1 microgram/kg/min every 2 min) was administered intravenously on two consecutive days. Heart rate (HR), systolic and diastolic blood pressure (BP), as well as a wall motion score in 16 segment (WMS) and ejection fraction (EF) with 2D-echocardiography were determined at rest and during each increment. Viability of myocardial regions was assessed with 201thallium-SPECT (Table 1).

RESULTS

*p < 0.05 vs. rest, data: mean +/- SD. While E did not cause any side effects, patients complained about rash (n = 10), headache (n = 8), angina pectoris (n = 5), and anxiety (n = 2) during the administration of D. D and E are both able to recruit a potential inotropic reserve in infarcted myocardium, and thus, identify viable myocardium. In contrast to E, D caused an increase in HR and systolic BP. Enoximone-echocardiography seems to be a new, promising tool for the identification of viable myocardium.