Evaluation of non-ST segment elevation acute chest pain syndromes with a novel low-profile continuous imaging ultrasound transducer.

Background: This investigation was designed to test the hypothesis that continuous cardiac imaging using an ultrasound transducer developed in our laboratory (ContiScan) is superior to electrocardiogram (ECG) monitoring in the diagnosis of coronary artery disease (CAD) in patients with acute non-ST segment elevation chest pain syndromes.

Methods: Seventy patients with intermediate to high probability of CAD who presented with typical anginal chest pain and no evidence of ST segment elevation on the ECG were studied. The 2.

Implications of acute left ventricular remodeling during squatting stress echocardiography.

Background: We previously demonstrated that squatting induces left ventricular (LV) wall motion abnormalities (WMA) in areas subtended by stenotic coronary arteries. In addition, it was observed that some subjects developed acute changes in LV shape (acute left ventricular remodeling [ALVRM]) during squatting.

Objective: This study tested the hypothesis that patients with ALVRM during squatting echocardiography have higher incidences of severe coronary artery disease (CAD).

Comparison of squatting stress echocardiography and dobutamine stress echocardiography for the diagnosis of coronary artery disease.

Background: Dobutamine stress echocardiography (DSE) is commonly used for the diagnosis for coronary artery disease (CAD). We previously demonstrated that squatting induces wall motion abnormalities (WMA) in areas subtended by stenotic coronary arteries.

Objective: This study was designed to test the hypothesis that dobutamine and squatting stress echocardiography are equally useful for the diagnosis of CAD.

Detection of wall motion abnormalities during ambulatory echocardiography using a novel ultrasound transducer.

Background: This investigation was designed to determine whether transient wall motion abnormalities due to myocardial ischemia induced by walking could be detected by ambulatory echocardiography.

Methods: Two groups were studied. Group 1 consisted of 10 males (mean age 34 years) who had no symptoms of angina.

Changes in abdominal aortic diameter in response to the cold pressor test and nitroglycerin: a new noninvasive model for the assessment of endothelial-dependent and endothelial-independent vascular relaxation.

Coronary vascular responses to the cold pressor test (CPT) have been shown to parallel changes caused by infusion of acetylcholine. Whereas the CPT is a method of assessing endothelial-dependent vasodilation, nitroglycerin produces endothelial-independent vasodilation. We performed histological studies on autopsy specimens of abdominal aorta and demonstrated that it is predominantly muscular artery.

Usefulness of transthoracic echocardiography in demonstrating coronary blood flow after coronary artery bypass grafting.

In this pilot study, we used transthoracic echocardiography to measure coronary sinus blood flow in 15 patients before and after coronary artery bypass grafting. Coronary sinus blood flow before and after revascularization was 274 +/- 95 and 451 +/- 102 ml/min, respectively (p <0.001).

Continuous recording of pulmonary artery diastolic pressure and cardiac output using a novel ultrasound transducer.

Background: The feasibility of hands-free transthoracic continuous determination of pulmonary artery (PA) diastolic pressure (PAD) and cardiac output (CO) by Doppler ultrasound has not been previously demonstrated. We developed a 2.5-MHz spherical transducer mounted in an external housing to permit steering in 360 degrees (Contison).

Detection of Barrett's epithelium by acoustic microscopy.

Barrett's esophagus is associated with increased risk of adenocarcinoma of the gastroesophageal junctional region. The presence of goblet cells (intestinal metaplasia) in columnar cell-lined esophageal mucosa defines Barrett's change. The diagnosis of Barrett's esophagus is based on the presence of intestinal metaplasia in a biopsy from an endoscopically visualized abnormal columnar epithelium.

Transesophageal Echocardiographic Assessment of Lesions of the Right Ventricular Outflow Tract and Pulmonic Valve.

To establish the role of biplane transesophageal echocardiography (TEE) in the assessment of congenital and acquired lesions involving the right ventricular outflow tract (RVOT) and pulmonic valve (PV), 28 consecutive RVOT and PV lesions in 22 consecutive patients were studied by two-dimensional and color Doppler transthoracic echocardiograms (n = 22), horizontal (n = 22) and vertical (n = 22) plane TEEs, cardiac catheterization (n = 15), cardiac surgery (n = 6), and magnetic resonance imaging (n = 1). Sixteen patients had congenital lesions, and six had acquired lesions. Longitudinal TEE clearly imaged 25 of 28 abnormalities, transverse TEE clearly imaged 12 of 28, and transthoracic echocardiography clearly imaged 9 of 28.