Abstract
Conflicting theories exist as to the occurrence of pulsus alternans. To identify the responsible mechanism, experiments were performed in dogs with spontaneous alternans. The electrocardiogram, aortic and ventricular pressures, stroke volume and segment lengths were monitored simultaneously. Results show insignificant variations in heart rate, left ventricular end-diastolic pressure (P <.01) and end-diastolic lengths (P <.01), but significant difference in aortic pulse pressure (P <.02), stroke volume (P <0.001) and end-systolic lengths (P <.05) between strong and weak beats. In addition, segment work was found to be different among regions. Thus, the present report indicates that the Frank-Starling mechanism is not responsible for the occurrence of pulsus alternans, and that alternating end-systolic dimensions, hence alternating myocardial contractility, sustain ventricular alternans.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 19 |
| Number of pages | 1 |
| Journal | IRCS Medical Science |
| Volume | 10 |
| Issue number | 1 |
| State | Published - 1982 |
All Science Journal Classification (ASJC) codes
- General Biochemistry, Genetics and Molecular Biology