![]() ![]() A wide variety of recordings was also made in other conditions such as congenital heart disease, pericarditis, and other cardio?vascular abnormalities. In the case of mitral stenosis a particularly extensive study was made as surgical operations for relief of mitfal stenosis were being developed at this time. The systolic and diastolic murmurs occurring in apparently normal hearts and in the presence of aortic and mitral valvular disease were also recorded as they were encountered and when precise diagnosis was in doubt. In this way, third heart sounds were recorded in normal hearts and abnormal auscultatory phenomena such as gallop rhythms accompanying hypertension, congestive cardiac failure, congenital heart disease, myocardial infarction and bundle-branch block and other conditions were studied. The only factors that influenced the selection of cases were,therefore, firstly, the fitness of patients and their ability to co-operate without undue fatigue or distress, and, secondly, the desire by the clinician to obtain graphic information of a doubt?ful auscultatory sign which was felt to be of diagnostic import?ance or of medical interest. Later, as techniques improved and as more satisfactory phonocardiograph machines became available, all types of heart sounds and murmurs were recorded as they were encountered in the daily routine. In this way recordings were made week by week, at first of a fairly simple nature and thus, in the early months there was a tendency for recordings to be made of gallop rhythms rather than cardiac murmurs, the reason for this being that the low frequency of the heart sounds make them relatively easy to record when com?pared with the high frequency of heart murmurs. Experience was sought in the study of all varieties of cardiovascular disease and the work was not confined to one particular type of sound, murmur or condition. As a research instrument the phono?cardiograph is of proved value as an adjunct to the teaching of cardiology its value is also obvious but whether or not it can take its place beside the electrocardiograph as an apparatus of practical value to the clinician is still undecided. ![]() It is already clear that, in the past, phonocardiographic analysis of the various heart sounds and murmurs occurring in health and disease has been of great interest to the physiologist and the enquiring physician. The work presented here was originally undertaken with three main objects in view - firstly, to master the technique of phonocardiography secondly, to decide whether accurate visual records of the heart sounds could be made with reasonable ease and, finally, to decide what actual value such recordings might have for the practising physician. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |