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
In left ventricular dysfunction, the ejection fraction will decrease significantly, causing reduction in stroke volume, hence causing a increase in end-diastolic volume. There may initially be a tachycardia as a compensatory mechanism to try to keep the cardiac output constant. As a result, during the next cycle of systolic phase, the myocardial muscle will be stretched more than usual and as a result cause an increase in myocardial contraction, related to the Frank–Starling physiology of the heart. This in turn results in a stronger systolic pulse.
Causes
Life Threatening Causes
Common Causes
Causes by Organ System
| Cardiovascular | Atrial Septal Defects, cor triatriatum, left heart failure, fallot tetralogy, persistent fetal circulation, mitral valve stenosis, mitral valve insufficiency, ventricular Septal Defect |
| 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 | High Altitude(chronically). |
| Gastroenterologic | Portal Hypertension. |
| Genetic | Alveolar capillary dysplasia with misalignment of pulmonary veins, cholesterol ester storage disease, cystic fibrosis, Gaucher disease, Indian familial childhood cirrhosis[2] |
| Hematologic | Myeloproliferative disorders, paroxysmal nocturnal haemoglobinuria, polycythemia Vera, splenectomy(due to thrombophilia), sickle cell disease. |
| Iatrogenic | No underlying cause |
| Infectious Disease | HHV-8, schistosoma japonicum and schistosoma mansoni |
| Musculoskeletal / Ortho | Idiopathic spinal scoliosis |
| Neurologic | No underlying cause |
| Nutritional / Metabolic | No underlying cause |
| Obstetric/Gynecologic | No underlying cause |
| Oncologic | No underlying causes |
| Opthalmologic | No underlying causes |
| Overdose / Toxicity | Diethylpropion, monocrotaline,[3] phentermine, radiation exposure (fibrosing mediastinitis and pulmonary fibrosis). |
| Psychiatric | No underlying causes |
| Pulmonary | No underlying causes |
| Renal / Electrolyte | Chronic renal failure on dialysis |
| Rheum / Immune / Allergy | No underlying causes |
| Sexual | No underlying causes |
| Trauma | No underlying causes |
| Urologic | No underlying causes |
| Miscellaneous | Gaucher disease, glycogen storage diseases, idiopathic spinal scoliosis, |
Causes in Alphabetical Order
Related Chapters
References
- ↑ Euler D (1999) Cardiac alternans: mechanisms and pathophysiological significance. Cardiovascular Research. Vol. 42. P. 583-590. PMID 10533597
- ↑ Nayak NC, Chitale AR (2013). "Indian childhood cirrhosis (ICC) & ICC-like diseases: the changing scenario of facts versus notions". Indian J Med Res. 137 (6): 1029–42. PMC 3734708. PMID 23852284.
- ↑ Schultze AE, Roth RA (1998). "Chronic pulmonary hypertension--the monocrotaline model and involvement of the hemostatic system". J Toxicol Environ Health B Crit Rev. 1 (4): 271–346. doi:10.1080/10937409809524557. PMID 9776954.