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THE LUNGS IN CONGESTIVE HEART-FAILURE
296 THE LUNGS IN CONGESTIVE HEART-FAILURE CHARACTERISTIC changes in the lungs in heart-failure have long been recognised radiologically. Pulmonary oedema due to acute left ventricular failure produces massive shadows radiating from both hilar regions in the form of a fan or butterfly wing, the base and apex of the lung being unaffected.1 These shadows are caused by extensive transudation of fluid from the capillaries of the lung, and they may persist after the acute heart-failure has clinically resolved. Occasionally the oedema fluid may become thick, gelatinous, or fibrinous, and finally organised, so that the pulmonary shadows may fail to resolve. This has been demonstrated in patients dying of uræmia,2 and more recently in patients with recurrent episodes of hypertensive left ventricular failure who have been kept alive by hypotensive drugs.3 Pleural effusions are common in congestive failure, and they are usually bilateral, but sometimes unilateral (generally left-sided). It is now clear that hydrothorax can occur in pure left-sided heart-failure,4 although it is most common in combined failure of both ventricles ; and it is rare in isolated right-sided failure. Pleural effusion confined to the left side may accompany isolated left-sided failure with sinus rhythm.5 These effusions are associated with enlargement of the heart and main The lung-fields may be hazy, pulmonary arteries. reflecting pulmonary congestion. In left-sided failure, the chest radiograph may also show horizontal lines in the costophrenic sulcus,6—8 similar to those seen in mitral stenosis, and probably attributable to interlobular oedema and engorged lymphatics,9 but not so numerous, well-defined, or persistent as in severe mitral disease. Pleural effusions may be encysted or interlobar, and they may mimic other conditions10 so that more detailed radiological examination may be needed to localise them accurately. Sometimes such effusions may become partially organised, producing pleural thickening and elevation of the diaphragm. Short9 has lately reviewed the radiological appearances in left-sided failure. He studied 51 patients with left-sided failure or left ventricular enlargement unassociated with mitral disease or emphysema. The radioof these were examined without knowgraphs patients ledge of the clinical findings. He detected six types of abnormality due to pulmonary congestion : hilar cloud-
ing, pulmonary clouding, hydrothorax (costophrenic or lamellar), interlobar thickening, interlobular (costophrenic) lines, and venous distension in the upper zones. An abnormal pattern was found in 67 radiographs from 30 patients, and the commonest abnormality was hilar clouding. Pleural involvement was noted in 51 films (hydrothorax in 29 and thickening of the fissures in 22). The hydrothorax was bilateral in 17, right-sided in 10, and left-sided in 2. 13 of the 29 patients with hydrothorax had pure left-sided failure and 16 had failure of both ventricles. The type of failure did not appear to There was influence the localisation of the effusions. generally only moderate clouding of the lung-fields, and frank pulmonary oedema was seen in only 2 cases. Costophrenic lines were seen in 20 films, and in 10 they were accompanied by a small effusion. In 13 radiographs there was of the pulmonary trunk ; and was conclusively demonvenous distension pulmonary strated 8 times. Pulmonary congestion was demonstrated
enlargement
1. Jackson, F. Brit. Heart J. 1951. 13, 503. 2. Doniach, I. Amer. J. Roentgenol, 1947, 58, 620. 3. Doniach, I., Morrison, B., Steiner. R. E. Brit. Heart J. 1954, 16, 101. 4. Bedford, D. E. Lancet, 1939, i. 1303. 5. Bedford. D. E.. Lovibond. J. L. Brit. Heart J. 1941, 3, 93. 6. Kerley, P. Brit. med. J. 1933, ii, 594. 7. Shanks, S. C., Kerley, P. Textbook of X-Ray Diagnosis by British Authors. 2nd ed., London. 1951 ; vol. 2. 8. Fleischner, F. G., Reiner, L. New Engl. J. Med. 1954, 250, 900. 9. Short, D. S. Brit. Heart J. 1956, 18, 233. 10. Newman, W., Jacobson. H. G. Amer. Heart J. 1951, 42, 184.
in 7 patients in whom the presence of In general, th uncertain clinically. radiological signs corresponded to the clinical course o the heart-failure, clearing rapidly when clinical signs o failure disappeared. Short considers that careful X-ray examination may permit a diagnosis of congestive hear failure before clinical signs appear. Certainly his paperi of radiography and a useful reminder of the value the in of heart and fluoroscopy lungs patients with aetl1J or threatened left-sided failure.
radiologically
heart-failure
was
MYXOMATOSIS WITH the possible exception of foot-and-mouth disease no infectious disease of animals has excited wider interea in this country in recent years than myxomatosis 1 rabbits. The advisory committee set up by the Govern ment considered the effects that any great reduction ir the number of rabbits might have on agriculture, forestry and the trade in fur felt and rabbit meat. In its report. made in 1954, the committee suggested that to restrict the spread of the disease would serve no useful purpose ; in other words, myxomatosis should he allowed to run its course. Since then myxomatosis ha, spread, irregularly but progressively, throughout tht country, though not without protests from animal loven and warnings from animal ecologists about the effect ou rabbit predators such as foxes, stoats, and buzzard.. which have been deprived of much of their naturdl food. Myxomatosis may spread by direct contact between rabbits, but there is much evidence incriminating fleas and mosquitoes as vectors of the disease ; and an important method of transmission, at least in Australia. Work on the virus forms of is by mosquito bite. encephalitis has shown that after mosquitoes become infected by ingesting virus-containing blood, the vims multiplies within the insect ;and there is a latent period during which mosquito bites do not carry infection. But the concentration of virus in the mosquito rapidly reache; a peak and thereafter does not greatly decrease with time. Workers in Australia2 have investigated the possibility of a similar course of events in rabbit myxomatosis ;but they found that the transmission of myxoma virus differs radically from that of the encephalitis viruses in that myxoma virus does not multiply in the vector but is transferred mechanically by the con taminated mouthparts of mosquitoes which have bitten through the skin lesions of infected rabbits. Moreover. the various species of mosquito differ in their capacity to transmit the disease, and this difference may be related to the biting habits of the insects, the anatomy of their mouthparts, and their propensity for feeding if interrupted. Deep probing and persistent attempts to feed after interruption would undoubtedly favour the transmission of myxomatosis. Another problem which has been investigated in Australia is the variation in transmissibility between different strains of virus. Fenner et a1.3 concluded that this variation depends, not on the intensity and duration of vir2emia, as is the case in encephalitis, but on the extent to which the virus multiplies in the skin of the rabbit and on the average duration of life of infectious rabbits. Several strains of virus have been studied experimentally and in the field, and the survival potenti,ù of these strains under field conditions was found to be related to the length of time during which an infected rabbit presents lesions to the insect vectors which iua settle upon it. A long illness in a rabbit with extensive lesions will increase the opportunities for insect vectors to feed upon it ;; and this would explain the presen:
repeated
1. See Lancet, 1954, i, 920. 2. Day, M. F., Fenner, F., Woodroofe, G. M. J. Hyg., Camb. 1956, 54, 258. 3. Fenner, F., Day, M. F., Woodroofe, G. M. Ibid, p. 284.
ing, pulmonary clouding, hydrothorax (costophrenic or lamellar), interlobar thickening, interlobular (costophrenic) lines, and venous distension in the upper zones. An abnormal pattern was found in 67 radiographs from 30 patients, and the commonest abnormality was hilar clouding. Pleural involvement was noted in 51 films (hydrothorax in 29 and thickening of the fissures in 22). The hydrothorax was bilateral in 17, right-sided in 10, and left-sided in 2. 13 of the 29 patients with hydrothorax had pure left-sided failure and 16 had failure of both ventricles. The type of failure did not appear to There was influence the localisation of the effusions. generally only moderate clouding of the lung-fields, and frank pulmonary oedema was seen in only 2 cases. Costophrenic lines were seen in 20 films, and in 10 they were accompanied by a small effusion. In 13 radiographs there was of the pulmonary trunk ; and was conclusively demonvenous distension pulmonary strated 8 times. Pulmonary congestion was demonstrated
enlargement
1. Jackson, F. Brit. Heart J. 1951. 13, 503. 2. Doniach, I. Amer. J. Roentgenol, 1947, 58, 620. 3. Doniach, I., Morrison, B., Steiner. R. E. Brit. Heart J. 1954, 16, 101. 4. Bedford, D. E. Lancet, 1939, i. 1303. 5. Bedford. D. E.. Lovibond. J. L. Brit. Heart J. 1941, 3, 93. 6. Kerley, P. Brit. med. J. 1933, ii, 594. 7. Shanks, S. C., Kerley, P. Textbook of X-Ray Diagnosis by British Authors. 2nd ed., London. 1951 ; vol. 2. 8. Fleischner, F. G., Reiner, L. New Engl. J. Med. 1954, 250, 900. 9. Short, D. S. Brit. Heart J. 1956, 18, 233. 10. Newman, W., Jacobson. H. G. Amer. Heart J. 1951, 42, 184.
in 7 patients in whom the presence of In general, th uncertain clinically. radiological signs corresponded to the clinical course o the heart-failure, clearing rapidly when clinical signs o failure disappeared. Short considers that careful X-ray examination may permit a diagnosis of congestive hear failure before clinical signs appear. Certainly his paperi of radiography and a useful reminder of the value the in of heart and fluoroscopy lungs patients with aetl1J or threatened left-sided failure.
radiologically
heart-failure
was
MYXOMATOSIS WITH the possible exception of foot-and-mouth disease no infectious disease of animals has excited wider interea in this country in recent years than myxomatosis 1 rabbits. The advisory committee set up by the Govern ment considered the effects that any great reduction ir the number of rabbits might have on agriculture, forestry and the trade in fur felt and rabbit meat. In its report. made in 1954, the committee suggested that to restrict the spread of the disease would serve no useful purpose ; in other words, myxomatosis should he allowed to run its course. Since then myxomatosis ha, spread, irregularly but progressively, throughout tht country, though not without protests from animal loven and warnings from animal ecologists about the effect ou rabbit predators such as foxes, stoats, and buzzard.. which have been deprived of much of their naturdl food. Myxomatosis may spread by direct contact between rabbits, but there is much evidence incriminating fleas and mosquitoes as vectors of the disease ; and an important method of transmission, at least in Australia. Work on the virus forms of is by mosquito bite. encephalitis has shown that after mosquitoes become infected by ingesting virus-containing blood, the vims multiplies within the insect ;and there is a latent period during which mosquito bites do not carry infection. But the concentration of virus in the mosquito rapidly reache; a peak and thereafter does not greatly decrease with time. Workers in Australia2 have investigated the possibility of a similar course of events in rabbit myxomatosis ;but they found that the transmission of myxoma virus differs radically from that of the encephalitis viruses in that myxoma virus does not multiply in the vector but is transferred mechanically by the con taminated mouthparts of mosquitoes which have bitten through the skin lesions of infected rabbits. Moreover. the various species of mosquito differ in their capacity to transmit the disease, and this difference may be related to the biting habits of the insects, the anatomy of their mouthparts, and their propensity for feeding if interrupted. Deep probing and persistent attempts to feed after interruption would undoubtedly favour the transmission of myxomatosis. Another problem which has been investigated in Australia is the variation in transmissibility between different strains of virus. Fenner et a1.3 concluded that this variation depends, not on the intensity and duration of vir2emia, as is the case in encephalitis, but on the extent to which the virus multiplies in the skin of the rabbit and on the average duration of life of infectious rabbits. Several strains of virus have been studied experimentally and in the field, and the survival potenti,ù of these strains under field conditions was found to be related to the length of time during which an infected rabbit presents lesions to the insect vectors which iua settle upon it. A long illness in a rabbit with extensive lesions will increase the opportunities for insect vectors to feed upon it ;; and this would explain the presen:
repeated
1. See Lancet, 1954, i, 920. 2. Day, M. F., Fenner, F., Woodroofe, G. M. J. Hyg., Camb. 1956, 54, 258. 3. Fenner, F., Day, M. F., Woodroofe, G. M. Ibid, p. 284.