Doppler Ultrasound Evaluation of Circulatory Support Devices

Abstract

In the setting of mechanical circulatory support devices, including ventricular assist devices, extracorporeal membrane oxygenation, intraaortic balloon pumps, and the total artificial heart, the spectral Doppler waveform is significantly altered, reflecting systemic hemodynamic changes. As the prevalence of these devices increases, a better understanding of both the devices themselves and their associated Doppler ultrasound findings is necessary for accurate image interpretation. This article reviews the clinical indications, pathophysiology, and sonographic findings of these devices, with emphasis on the variation in arterial Doppler waveforms that can be seen with normal function, as well as the major complications.

Intraoral Ultrasonography for the Exploration of Periodontal Tissues: A Technological Leap for Oral Diagnosis

“…Elastographic analysis can even measure the elasticity of periodontal tissues [26]. Doppler ultrasound, for its part, makes it possible to visualize and measure vascularization, a predictive factor for gingival surgery [27]. Ultrasound imaging is also an important way to increase the sensitivity and specificity of our diagnosis.…”

Manifestations of circulatory assist devices in noninvasive arterial duplex evaluation: A pictorial review

“…Therefore, LVADs with centrifugal pump designs produce a more pulsatile waveform relative to LVADs with axial pump designs. 5,6 In addition to pump design, the systolic pulsatility of the Doppler waveforms of LVAD patients depends on the device settings, and the patient’s myocardial reserve. 6 Patients with poor myocardial reserve will have a decreased pulsatility as compared to patients with a preserved myocardial reserve.…”

“…5,6 In addition to pump design, the systolic pulsatility of the Doppler waveforms of LVAD patients depends on the device settings, and the patient's myocardial reserve. 6 Patients with poor myocardial reserve will have a decreased pulsatility as compared to patients with a preserved myocardial reserve. Furthermore, the HeartMate III can be programmed using pump speed modulation to generate more pulsatility from the LVAD and to intermittently increase flow from the left ventricle during systole and diastole.…”

“…9 Doppler waveform in the presence of ECMO demonstrates a high-flow, low-resistive pattern with variable systolic pulsatility, depending on the myocardial reserve of a patient and degree of ECMO support. 6 Monophasic lowresistive spectral Doppler waveform with diminished systolic pulsatility suggests poor myocardial reserve but may also be seen with increased VA ECMO support (Figure 6A). High-flow, monophasic, low-resistive spectral Doppler waveform with systolic pulsatility suggests preserved myocardial reserve (Figure 6B).…”