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Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts
Published on: November 7, 2019
Hemodynamic responses to noninvasive external cardiac pacing.
M D Feldman1, P M Zoll, J M Aroesty
1Charles A. Dana Research Institute, Beth Israel Hospital, Boston, Massachusetts.
The American Journal of Medicine
|March 1, 1988
Summary
Noninvasive external cardiac pacing reliably captures the heart and is hemodynamically safe. This pacing method increases heart pressures and oxygen consumption, potentially causing angina in patients with coronary artery disease.
Area of Science:
- Cardiology
- Cardiovascular Physiology
Background:
- Noninvasive external cardiac pacing offers reliable electrical capture with reduced patient discomfort.
- Hemodynamic responses to this pacing method have not been previously documented.
Purpose of the Study:
- To describe the hemodynamic responses to noninvasive external cardiac pacing.
- To assess the safety and effects of this pacing technique in patients undergoing cardiac catheterization.
Main Methods:
- Noninvasive pacing was applied to 16 patients (13 with coronary artery disease) at increasing heart rates up to 85% of age-predicted maximum.
- Hemodynamic parameters including pressures, cardiac index, arteriovenous oxygen difference, and oxygen consumption were monitored.
Main Results:
- Maximal pacing increased atrial, pulmonary artery, and mean aortic pressures, with unchanged cardiac index due to increased arteriovenous oxygen difference and oxygen consumption.
- Post-pacing, pulmonary artery pressure and oxygen consumption remained elevated, while cardiac index rose.
- Angina and elevated left ventricular end-diastolic pressure occurred in 8 patients with coronary artery disease at peak pacing.
Conclusions:
- Noninvasive external cardiac pacing increases right and left heart filling pressures and oxygen consumption, with persistent effects after pacing.
- This pacing mode may induce angina and hemodynamic changes indicative of myocardial ischemia.
- Noninvasive pacing appears hemodynamically safe, maintaining cardiac index and aortic pressure.
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