Thus, poor ventilation leading to hypercapnia, left heart failure leading to interstitial edema (impairing gas exchange), asthma causing bronchoconstriction (limiting airflow) and muscle fatigue leading to ineffective respiratory muscle action could all contribute to a feeling of dyspnea.Efferent signals are the motor neuronal signals descending to the respiratory muscles. The most important respiratory muscle is the diaphragm. Other respiratory muscles include the external and internal intercostal muscles, the abdominal muscles and the accessory breathing muscles.As the brain receives its plentiful supply of afferent information relating to ventilation, it is able to compare it to the current level of respiration as determined by the efferent signals. If the level of respiration is inappropriate for the bodys status then dyspnea might occur. There is also a psychological component to dyspnea, as some people may become aware of their breathing in such circumstances but not experience the typical distress of dyspnea. Diagnosis
The initial approach to evaluation begins by assessment of the airway, breathing, and circulation followed by a medical history and physical examination. Signs and symptoms that represent significant severity include hypotension, hypoxemia, tracheal deviation, altered mental status, unstable dysrhythmia, stridor, intercostal indrawing, cyanosis, tripod positioning, pronounced use of accessory muscles (sternocleidomastoid, scalenes) and absent breath sounds.A number of scales may be used to quantify the degree of shortness of breath. It may be subjectively rated on a scale from 1 to 10 with descriptors associated with the number (The Modified Borg Scale).
Life expectancy and quality of life are therefore the same or very close to that of the normal population, but check ups are recommended so that those few percent who need further treatment get it in time. History
The condition was largely unidentified until the mid-20th century. History of the condition prior to 1945 has been understood via post-mortem records, the first series of which was published in 1928, which examined cases as far back as 1791. The first surgery for coarctation of the aorta was performed by Clarence Crafoord and G. Nylin on October 19, 1944 in Stockholm, Sweden on a 12-year old boy.An anecdotal history statement describes the first diagnosed case of the coarctation of the aorta in Julia the daughter of the French poet Alphonse de Lamartine after the autopsy in 1832 in Beirut, the referenced manuscript still exists in one of the Maronite monasteries in Mount Lebanon. References
Further reading
Toro-Salazar, Olga H; Steinberger, Julia; Thomas, William; Rocchini, Albert P; Carpenter, Becky; Moller, James H (2002). "Long-term follow-up of patients after coarctation of the aorta repair". The American Journal of Cardiology. 89 (5): 541–7. doi:10.1016/S0002-9149(01)02293-7. PMID 11867038. Brouwer, Rene M.H.J. ; Erasmus, Michiel E.; Ebels, Tjark; Eijgelaar, Anton (1994). "Influence of age on survival, late hypertension, and recoarctation in elective aortic coarctation repair. Including long-term results after elective aortic coarctation repair with a follow-up from 25 to 44 years". The Journal of Thoracic and Cardiovascular Surgery. 108 (3): 525–31. doi:10.1016/S0022-5223(94)70264-0. PMID 8078345. Jenkins, N.P. (1999).