Acta Andina 2001; 9 (1-2): 63 High altitude physiology. Cardiac and respiratory aspects a CIBA Foundation symposium in honour of Profesor Alberto Hurtado Londres, 1971 Dr. Emilio A. Marticorena Profesor Emérito de Medicina, UNMSM Docente Investigador. Fuerza Aérea del Perú Hospital Las Palmas SUMMARY AND CONCLUSIONS Anatomy of the coronary circulation at high altítude. ARIAS- STELLA J Y TOPILSKY M (1) Using the method of preparing casts of the coronary arterial system through aortic injection of rapid1y polymerising acrylic resin at a pressure of 150-200 mmHg, followed by fixation and corrosion, a different patterrí has been found in the vascularization of individuals from Cerro de Pasco (4375 m) from that seen in subjects from sea level. These results are compared with those recently obtained in our laboratory by Dr. Carmelino in subjects from Puno (3466-4287 m), using the post?mortem stereoangiographic method. Both studies show that the number of branches leaving the main coronary trunks is greater and the peripheral ramifications are more numerous at high altitudes. The physiological and clinical significance of these findings is discussed. Coronary blood flow and rnyocardial metabolism in man at high altitude MORET PR (2) Coronary blood flow and rnyocardial metabolism were studied in normal subjects living in Perú and Bolivia at three different altitudes: Lima (150 msnm), La Paz (3700 msnm) and Cerro de Pasco (4375 msnm). Coronary blood flow is lower at high altitude, as is the oxygen consumption of the rnyocardium, with the result that rnyocardial efficiency is greater. The lower coronary flow at high altitude is not compensated for by any increased oxygen transport capacity of the blood. Substrates usually extracted by the heart -glucose, lactate, pyruvate and free fatty acids- are the same at high and low altitude, but at high altitude the heart consumes more carbohydrates, especially lactate, and there are no signs of anaerobic metabolism. The lower coronary blood flow and oxygen consumption and absence of signs of anaerobic metabolism at high altitude suggest an adaptation of cellular metabolism to low oxygen pressure. Six patients with chronic mountain sickness were also Acta Andina 2001; 9 (1-2): 63 studied. Coronary blood flow was higher than in the normal groups, and in some cases the rnyocardium seems to be slight1y underperfused. The percentage oxygen extraction is increased, in contrast to the normal subjects, and the extraction of metabolites also differs. Sorne observations on the blochemistry of the myocardium at high altitude HARRIS P (3) Measurements of succinic dehydrogenase and lactic dehydrogenase activity have been made on rnyocardial homogenates from guinea pigs, rabbits and dogs indigenous to high altitude and compared with measurements made on the same species at sea level. A consistent increase in the activity of succinic dehydrogenase was found in the high altitude animals but no significant difference in lactic dehydrogenase. Analyses of the lipid content of the rnyocardium have shown that there is a consistent increase in total lipid, total phospholipid, cholesterol and sphingornyc1in in the rnyocardium of the three species of animal at high altitude. Utilización de la altura natural y simulada en rehabilitación cardiaca coronaria En 1971, tres de los participantes en el Sympositim Ciba de Fisiología de Altura en 1971 en Londres - Inglaterra, en honor del Profesor Alberto Hurtado; expusieron respectivamente -sus observaciones en: 1) La profusa vasculatura coronaria en individuos de la altura (A) respecto de especímenes de nivel del mar (NM) 1, 2) Menor flujo coronario con mayor eficiencia miocárdica en el nativo de A2 y 3) Mayor actividad enzimática del miocardio 1 dehydrogenasa succinica, en animales menores de A 1. Estos tres enfoques por investigadores separados, orientados a la exploración del miocardio de A y de NM, han contribuido al desarrollo de los procedimientos que actualmente utilizan hipoxia natural (Andes) y Altura Simulada (Cámara Hipobárica) con fines - específicos- de Rehabilitación Cardiaca Coronaria (RCC). En este sentido, es Perú -en el mundo- que desplaza por primera vez a la A (5000 m) pacientes coronarios con y sin infarto de miocardio con fines de RCC4. Retornando a la modalidad de A Simulada (CH), se reporta por Perú en 1994 1. Ese mismo año, se menciona la primera experiencia soviética 1. Actualmente en el Perú se profundizan los mecanismos que pretenden explicar cómo actuaría la H rehabilitando al miocardio, considerando que probablemente es al nivel de la biología molecular donde tales mecanismos tendrían lugar7-8. Finalmente, es un privilegio para el comentarista de estas líneas de investigación, haberse ocupado ajustadamente sobre la trascendencia que significa la contribución de los investigadores: Arias Stella, Moret y Harris en el manejo actual de la RCC con hipoxia, en el Perú y fuera de él. Acta Andina 2001; 9 (1-2): 63 REFERENCIAS BIBLIOGRAFICAS 1. Arias Stella J y Topilsky M: Anatomy of the coronary circulation at high altitude, High Altitude Physiology: Cardiac and Respiratory Aspects, A Ciba Foundation Symposium, Edit. R. Porter and J. Knight, Churchill Livingstone, London, pp. 149-154, 1971. 2. Moret PR: Coronary blood flow and myocardial metabolism in man at high altitude, High Altitude Physiology Cardiac and Respiratory Aspects, A Ciba Foundation Symposium Edit. R. Porter and J. Knight, Churchill Livingstone, London, pp. 131-144, 1971. 3. Harris P: Some observations on the biochemistry of the rnyocardium at high altitude, High Altitude Physiology Cardiac and Respiratory Aspects, A Ciba Foundation Symposium, Edit. R. Porter and J. Knight, Churchill Livingstone, London, pp 125129,1971. 4. Marticorena EA (1984?85) Nueva técnica en rehabilitación cardíaca y prevención primaria coronaria: utilización de las grandes alturas. Areh. Inst. Biol.. and. 13: 189?206. 5. Marticorena EA, Marticorena JM, Contreras A et. al. (1994) Cardiac rehabilitation of coronary bypassed patients natural and simulated high altitude techniques. First World Congress of High Altitude Medicine and Physiology, La Paz, Bolivia. Abst. 101. 6. Thinkov AN, Kotz Yl, Alioshin IA (1994) The first expericnce of treatment of patients with ischemic heart disease using the method of adaptation to intermittent hypoxia in an altitude chamber, Hypoxia Med. J. 2: p. 73, Abst. 115. 7. Marticorena EA (1998) Bases moleculares hipóxicas en rehabilitación cardíaca coronaria con altura natural y simulada, Rev. Peruana de Cardiolog. XXIV: 2:177-186. 8. Marticorena EA y Col. (2001) Factor relajante del endotelio (ON) rehabilitación coronaria con cámara hipobárica, Rev. Peruana de Cardiolog. 27: 2:148-9.