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A patient with aortic valve endocarditis presented with severe aortic regurgitation, large vegetation, and a periannular cavity at transesophageal echocardiography consistent with an abscess. At surgery a common coronary ostium was found, which was responsible for the abnormal periannular image. Such congenital abnormality, although unusual, is an echocardiographic pitfall in the case of endocarditis.

The purpose of this study was to determine in an in vitro model the effect of pulsatile pressure on the decay of echocardiographic contrast agents. Use of contrast agents for quantitative assessment of perfusion requires understanding of the factors controlling their rates of disappearance. Prior studies have shown that constant pressure affects the rate of disappearance of these agents. It is not known whether pulsatile pressure influences the rate of decay of contrast agents. In an in vitro chamber, three contrast agents (Albunex, hand-agitated saline solution, and hand-agitated Angiovist) were exposed to pulses of pressure at three rates (30, 60, and 120 pulsations/min), keeping pressure characteristics (peak, nadir, and mean) within a narrow range. Five injections were performed for each agent at each rate. Two-dimensional echocardiographic images of the effects of contrast material were recorded from injection until total disappearance. Videointensity was measured and time-intensity curves were generated. These curves of intensity decay were fitted to an exponential decay function (I = Ae-lambda t) and the velocity of decay (lambda) was used for comparisons. For all agents, intensity of contrast decreased over time. Saline solution and Angiovist, but not Albunex, showed pulsatile decreases in intensity of contrast with each peak pressure and partial recovery of contrast intensity with each nadir pressure. (ABSTRACT TRUNCATED AT 250 WORDS)

Contrast echocardiography has been applied to identify cardiac structures, shunts, and perfusion territories. Most recently, quantification of flow has been proposed based on disappearance of contrast intensity. This requires that contrast agents are stable and produce a predictable effect. To assess the possible effect of pressure on their stability, the rates of backscatter decay of four echocardiographic contrast agents (Albunex, Levovist, agitated Angiovist, and agitated saline solution) exposed to constant pressures (0, 50, 100, 150, and 200 mm Hg) were quantitated. Contrast was recorded by echocardiography and measured to construct time-intensity curves. The peak decay rate for each agent at each pressure was determined. For all four agents, contrast intensity (I) decreased over time and could be described by the sigmoid function: I = a [e-lambda(t-ts)/1 + e-lambda(t-ts)] + C. Peak decay rate was significantly affected by pressure (p < 0.005) in a proportionate fashion. At pressures of 0, 100, and 200 mm Hg, the rates increased for each agent in the following fashion: Albunex, 0.144 +/- 0.109 to 0.410 +/- 0.142 to 1.442 +/- 0.309; Levovist, 0.060 +/- 0.023 to 0.162 +/- 0.049 to 0.495 +/- 0.142; Angiovist, 0.089 +/- 0.028 to 0.166 +/- 0.057 to 0.224 +/- 0.027; and saline solution, 0.068 +/- 0.039 to 0.110 +/- 0.036 to 0.154 +/- 0.057. The effect of pressure on the peak rate of contrast disappearance (lambda) was significantly different among agents (p < 0.001). Thus attempts to quantitate blood flow with contrast agents must take into account the influence of pressure.