A mechanical arm for spatial registration of two-dimensional echocardiographic sections.

The accurate calculation of left ventricular (LV) wall motion from two-dimensional echocardiographs will require the accurate registration of the position from which each two-dimensional (2-D) view was obtained. This paper describes a mechanical arm with five degrees of freedom that was developed so that the position and orientation of 2-D echo sections could be calculated in three-dimensional space. High precision potentiometers, direct or gear driven, permit calibration and measurement of each of the five movements.

Quantitation of aortic insufficiency using a catheter-tip velocity transducer.

Bidirectional instantaneous aortic root blood flow was measured in 18 patients with aortic insufficiency (AI) using a catheter-tip velocity transducer. The magnitude of AI was quantitated by determining total forward systolic flow from the area of the flow velocity curve above the zero baseline and regurgitant diastolic flow from the curve area below the baseline. Effective forward flow (stroke volume) was calculated as the difference between total forward systolic flow and regurgitant diastolic flow.

Echocardiographic analysis of systolic and diastolic left ventricular wall motion during transient myocardial ischemia.

Left ventricular (LV) wall motion (anterior and posterior) and simultaneous LV pressure were recorded during 30-second left anterior descending (LAD) or circumflex (CX) coronary artery occlusions in open-chest dogs to provide an echocardiographic model of the evolution of wall motion changes during myocardial ischemia. Prominent diastolic echocardiographic motion changes of progressive decrease in LV wall rapid-filling velocities (RFS), slow-filling velocities (SFS), and increased end-diastolic diameter were accompanied by a marked increase in initial and end-diastolic pressures (150% and 70%, respectively; all p less than 0.05).

Effects of transient regional ischemia on left ventricular diastolic function.

Simultaneous left ventricular echograms and high-gain pressure recordings were made during 30 s of regional myocardial ischemia induced by snare occlusions of the proximal left anterior descending (LAD) or left circumflex (LCx) coronary arteries in open-chest dogs. Left ventricular diastolic diameter (d) and pressure (p) were measured during slow filling. A normalized (for diameter D) distensibility estimate (DE = delta d/delta p/D) was calculated, as were slow filling slopes (SFSs) of the septum and posterior wall.

Use of catheter-tip velocity--pressure transducer to evaluate left ventricular function in man: effects of intravenous propranolol.

A catheter-tip velocity transducer with two high-fidelity pressure manometers was used to evaluate the left ventricular (LV) hemodynamic effects of intravenous propranolol (10 mg). Nine patients without clinical evidence of heart failure were studied. Pulsatile ascending aortic blood flow velocity and pressure and LV pressure were measured continuously during drug administration.

Echocardiographic analysis of systolic and diastolic left ventricular wall motion in normal man.

Although the motion of the left ventricular wall has been examined by angiographic and by echocardiographic studies in both experimental animals and in man, there are no complete studies of the motion of the left ventricular posterior wall throughout the entire cardiac cycle. Because the posterior wall can be demonstrated echocardiographically in essentially all patients, it offers a potential of wide clinical application in the evaluation of left ventricular function. This study was undertaken to provide a detailed inclusive analysis of the motion of the left ventricular posterior wall.

Intracardiac M-mode echocardiography for continuous left ventricular monitoring: method and potential application.

Because no accurate and readily applied method exists for continuous recording of left ventricular cavity dimensions and wall motion in man, we designed a catheter-mounted echocardiographic probe. The purpose of this report is to describe the instrumentation, technique, limitations, complications and preliminary observations employing the probe in humans. The echo transducer built into a cardiac allowed positioning in the right heart under fluoroscopy.

Angiographic definition of critical coronary artery stenosis.

In summary, it is hazardous to rely solely on coronary angiography to define critical coronary stenosis. Clinically, the physiologic significance of a narrowing observed at coronary angiography can best be evaluated by obtaining additional evidence of myocardial ischemia, i.e.

Pulsatile flow characteristics of aortic valve porcine heterografts in man.

Pulsatile flow characteristics in the ascending aorta were examined in 14 patients 12 months after aortic valve replacement with the glutaraldehyde-fixed porcine aortic heterograft. Analysis of the velocity signals permitted measurement of peak velocity, maximal acceleration, stroke volume, and ejection time in addition to the standard measurement of systolic aortic valvar gradient. Angiographic techniques permitted visualization of a pattern of blood flow in the ascending aorta.

Percutaneous left ventricular catheterisation with an ultraminiature catheter-tip pressure transducer.

Percutaneous left ventricular catheterisation with a 4F (O.D. 1.

Ergonovine testing for coronary artery spasm in patients with angiographic mitral valve prolapse.

Coronary artery spasm (CAS) has been postulated to be a pathophysiologic mechanism in the production of ischemic-like chest pain and ECG changes in patients with idiopathic mitral valve prolapse syndrome. To evaluate the possible role of symptomatic CAS evoked by ergonovine maleate, this agent was administered (0.05 to 0.