The use of the phonocardiograph in clinical cardiology.

The phonocardiograph was born soon after the electrocardiograph, but their growth has been unequal in that the latter has been applied immediately to clinical medicine and has flourished while the former test, used to display such murmurs as the presystolic and the one identified with patent ductus arteriosus, has become largely exhibitional and for that reason has lost ground. More recently, however, phonocardiography has shown signs of coming into its own, and he now predicted for it a place in cardiology not far behind electrocardiography. He proposed to show some of the ways in which the test had already contributed to our knowledge and to point the way in which it could be usefully developed in the future. In the first place, it had confirmed the clinical classification for Triple Heart Rhythm. Such a classification had become necessary owing to the confused terminology connected with this rhythm. All cases of triple heart rhythm fall naturally into three groups. First, from addition of the third heart sound which immediately follows the second sound; secondly, from addition of the fourth heart sound which immediately precedes the first heart sound, and thirdly, from addition of a sound in late systole. This third variety was an innocent condition and only assumed importance in its differentiation from the presence of the third heart sound. The first kind of triple heart rhythm was found in healthy subjects and in those conditions that produce right heart failure: this included mitral stenosis, hypertensive heart failure, emphysema, pulmonary embolism, primary pulmonary hypertension, auricular septal defect, constrictive pericarditis, cardiac infarction, and anxmia. He spoke briefly about each of these forms of triple heart rhythm. The second variety from addition of the fourth heart sound was found in prolonged A-V conduction or in left ventricular heart failure as in hypertensive heart failure, aortic incompetence and failure, and in cardiac infarction. Turning to Heart Murmurs, he stressed the importance of the phonozardiograph in confirming the reliability of certain clinical signs which had been assembled for the differentiation of innocent heart murmurs into five main varieties, and he outlined such signs. Concerning the murmurs of organic heart disease he mentioned how common it was for the phonocardiograph to show that the systolic murmur of mitral disease actually occurred during auricular systole as in the case of the presystolic murmur. The mid-diastolic murmur of mitral stenosis was even more important in the light of this newer test, so that in 74 cases of undoubted mitral stenosis the test had shown the presence of this murmur in all of them, but more cases need to be tested before one could say that it was an invariable finding. He then dealt with the murmurs of aortic valvular disease, hypertension, congenital heart disease, anemia, and heart block. Dr. Evans believed in the importance of the test not only for research purposes but also for clinical diagnosis in specific instances. The test had come to stay. We would not be able to live without it and for the good reason that our patients would not be able to live so well without it. In conclusion, he stressed three things in clinical auscultation. First, the advantage to clinical diagnosis of finding and placing the added heart sound which created a triple heart' rhythm. Secondly, that the quality and intensity of murmurs matter far less than their place in the cardiac cycle and in relation to the heart sounds. Thirdly, and above all else, the phonocardiograph had emphasized the importance of self catechism during clinical auscultation. He mentioned six questions which should be applied when the bell of the stethoscope rested on any part of the chest in the search for heart disease.