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[Phonomechanography of recent myocardial infarct: the jugulogram and carotidogram]
Insights
Mechanographic tracings reveal abnormal left systolic time in myocardial infarction patients. The ratio of pre-ejection period to left ventricular ejection time (PPE/LVET) may indicate long-term left ventricular function and recovery.
Area of Science:
- Cardiology
- Physiology
- Medical Diagnostics
Context:
- Myocardial infarction (MI) significantly impacts cardiac function.
- Assessing left ventricular function post-MI is crucial for patient management.
- Traditional diagnostic methods like jugular venography have limitations in MI assessment.
Purpose:
- To compare mechanographic tracings in recent myocardial infarction patients with control groups.
- To evaluate the utility of specific mechanographic parameters in reflecting cardiac changes post-MI.
- To identify reliable indicators of left ventricular dysfunction and recovery after myocardial infarction.
Summary:
- Mechanographic tracings from 30 MI patients showed shortened transmission time and rising phase duration, indicative of high peripheral resistance.
- Mean left systolic time, excluding qB2, was abnormal in MI patients and persisted for at least one month.
- The ratio of pre-ejection period to left ventricular ejection time (PPE/LVET) correlated with infarct size and was a lasting measure of depressed left ventricular function.
Impact:
- The PPE/LVET ratio shows promise as a long-term indicator of left ventricular function recovery post-MI.
- This ratio could guide patient lifestyle advice and monitor therapeutic efficacy.
- Further long-term studies are warranted to validate the prognostic value of PPE/LVET in myocardial infarction.
Abstract:
The mechanographic tracings of 30 patients with recent myocardial infarction, usually uncomplicated and without mitral incompetence, were compared with those of two control groups. The jugular venogram was unhelpful; full measurements can be made in only 40% of cases, and the scatter of normal values is too great. The carotid arteriogram is usually of the "arterial" type. Transmission time and the duration of the rising phase were both shortened. These findings result from the high level of peripheral resistance. The mean left systolic time was, except for qB2, abnormal, and remained so at the end of the first month. In this series there were neither maximal changes in J3, nor significant improvement from J12 nor J30. The largest increases in PPE and PPE/LVET were found in cases with large infarcts, and the largest reduction of LVET was in a case with left ventricular failure. There was no particular peculiarity corresponding with the site of the necrosis. Alteration in the ratio PPE/LVET is often a lasting measure of depressed left ventricular function. It would be most useful to study this ratio in the long term and to use it as a measure of recovery of function and as a guide to advising the patient on his future life style.