Use of Reactivated DEFINITY or LUMASON in Patients Undergoing Rest or Stress Echocardiography

Overview

Use of Reactivated DEFINITY® in or LUMASON Patients Undergoing Rest or Stress Echo Purpose of the study: Each patient undergoing a rest or stress echocardiogram uses a full vial of DEFINITY® or LUMASON contrast agent. During infusion, this often condenses back to its liquid phase due to manual pressure applied in the syringe. At this point, it is not optimal to be used at current ultrasound settings for stress echocardiography. This research project will test whether this condensed DEFINITY® or LUMASON can be reactivated by ultrasound using the same transducer used to image the patient. Eligibility: Same criteria as required for stress echo procedure. Interventions and Evaluations: Inject condensed DEFINITY® or LUMASON at end of stress test Follow Up: The patient would be observed by echo lab staff for half an hour following completion of the stress test. There would be no longitudinal follow up.

Patients undergoing previously scheduled rest or stress echocardiography with the primary investigator as the supervising physician will be identified and consented. The standard stress echocardiography procedure will be performed. Definity® or LUMASON will be removed from refrigeration and agitated for 45 seconds to vaporize into its gaseous phase. One mL of Definity® or LUMASON will then be diluted in 29 mL of isotonic, sterile saline. Patients will undergo baseline echocardiography followed by stress with either dobutamine or exercise. Standard Definity® or LUMASON will be injected intravenously into the subject via peripheral intravenous access obtained prior to the study by a registered nurse at the end of the rest or stress portion of the procedure coinciding with image acquisition. Contrast enhanced echocardiography by standard acoustic acquisition will be performed following rest or stress for the indicated diagnostic purpose of the test. By the end of the exam, the gaseous Definity® or LUMASON will have undergone manual compression via manual pressure and condensed back to its liquid phase. At this point, the compressed Definity® or LUMASON will be given intravenously with repeated transthoracic echocardiography. During this second round of image acquisition, real time (RT) imaging (35 Hertz) and 1:1 triggered (Tr) end systolic imaging at various mechanical indices (MI's) up to 1.2 will be performed in standard transthoracic echocardiography windows. Acoustic Intensity (AI) within the left ventricular (LV) cavity, the anterior myocardium (AM) and inferolateral myocardium (ILM) at end systole will be obtained at each MI setting with real time or triggered imaging. Differences in AI between Tr and RT imaging within the AM and ILM at each MI will be used to quantify bubble activation/destruction. Following image acquisition, the patient will be observed for 30 minutes by echo lab staff with nearby resuscitative equipment per current protocol. If no adverse events are noted, the patient will then be dismissed.