Pulsus alternans
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Varun Kumar, M.B.B.S.
Overview
Pulsus alternans is a physical finding with arterial pulse waveform showing alternating strong and weak beats.[1] It is almost always indicative of left ventricular systolic impairment, and carries a poor prognosis.
Pathophysiology
The mechanism of pulsus alternans was referred to Starling's law of the heart.[2] The ejection fraction will decrease significantly in cases of left ventricular dysfunction, which is the most important cause of pulsus alternans, causing reduction in stroke volume, and this reduction results in an increase in the end-diastolic volume. As explained by Starling's law, during the next cycle of systolic phase, the myocardial muscle will be stretched more than usual and causes an increase in myocardial contraction, this in turn results in a stronger systolic pulse.
Causes
Overview
Life Threatening Causes
Common Causes
Causes by Organ System
| Cardiovascular | No underlying causes |
| Chemical / poisoning | No underlying causes |
| Dermatologic | No underlying causes |
| Drug and Toxin Side Effect | No underlying causes |
| Ear Nose Throat | No underlying causes |
| Endocrine | No underlying causes |
| Environmental | No underlying causes |
| Gastroenterologic | No underlying causes |
| Genetic | [No underlying causes |
| Hematologic | No underlying causes |
| Iatrogenic | No underlying cause |
| Infectious Disease | No underlying causes |
| Musculoskeletal / Ortho | No underlying causes |
| Neurologic | No underlying cause |
| Nutritional / Metabolic | No underlying cause |
| Obstetric/Gynecologic | No underlying cause |
| Oncologic | No underlying causes |
| Opthalmologic | No underlying causes |
| Overdose / Toxicity | [No underlying causes |
| Psychiatric | No underlying causes |
| Pulmonary | No underlying causes |
| Renal / Electrolyte | No underlying causes |
| Rheum / Immune / Allergy | No underlying causes |
| Sexual | No underlying causes |
| Trauma | No underlying causes |
| Urologic | No underlying causes |
| Miscellaneous | No underlying causes |
Causes in Alphabetical Order
References
- ↑ Euler D (1999) Cardiac alternans: mechanisms and pathophysiological significance. Cardiovascular Research. Vol. 42. P. 583-590. PMID 10533597
- ↑ GLEASON WL, BRAUNWALD E (1962). "Studies on Starling's law of the heart. VI. Relationships between left ventricular enddiatolic volume and stroke volume in man with observations on the mechanism of pulsus alternans". Circulation. 25: 841–8. PMID 13899176.