Zeitschrift für Kardiologie
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Dobutamine stress echocardiography (DSE) leads to strong hypercontraction, tachycardia, and peripheral vasodilatation. In previous studies systolic obstruction of the left ventricular outflow tract (LVOT) was observed as a result of these factors. To evaluate left ventricular function and morphology in patients (pts) with induced systolic LVOT obstruction, we used continuous wave (CW) doppler registrations in combination with quantitative 2-D-echocardiography in 100 pts during routinely performed DSE (5-40 micrograms/kg/min). In addition left ventricular wall thickness was measured. Symptoms were registered using a standardised questionnaire and cardiac arrhythmias were counted over a two minute interval at rest and during the maximal heart rate of each patient. During DSE dynamic flow acceleration with late systolic peak velocity above 2 m/second (s) was considered to represent LVOT obstruction in pts with normal flow profiles in the LVOT before infusion of dobutamine. For invasive studies pts were investigated with femoral catheterisation by the method of Judkins. A greater than 50% stenosis was judged to be significant. ⋯ Intraventricular obstructions during DSE are often observed in pts with normal systolic function at rest and during peak stress, especially in the case of left ventricular hypertrophy. (ABSTRACT TRU