Clinical Significance of Ultrasound Classification Changes of Carotid Arteries
in Patients with Coronary Disease

Milan Đorić, Branko Lović, Ivan Tasić
Institut za prevenciju, lečenje i rehabilitaciju reumatičnih i kardiovaskularnih bolesti "Niška Banja"

Note: summary in Serbian
Napomena: sažetak na srpskom jeziku

INTRODUCTION

Colour Doppler echosonography is the first method of choice for the evaluation of neck blood vessels, which significantly increases reabillity of diagnosis and decreases the number of invasive diagnostic procedures.
During the years of clinical investigation a certain need for examination of carotid disease has been established, as well as its connections with coronary disease in etiological, diagnostic and therapeutic aspect. According to the present experiences and literary data, those two locations are strongly connected. So, we can freely say that its material mistake is to ignore one in clear clinical manifestation of the other especially in the presence of multiple risk factors, which are more or less common for both localisations (1,2,3).
Cerebro vascular disease occupies a very important place in medicine and is very important on socio-economic level. Mortality is in the third place, right behind cardiovascular disease and neoplasms. Morbidity per year is about 160 on 100.000 of the examined, and it exponentially grows during the process of aging. Man got it 5 times more often than women.
Consequences of cerebrovascular insults are very serious: 71 % of the patients after the period of 6 months have neurological sequels and only 10% fully manage to recover and come back to previous social and professional life (4).
Anatomic changes which may cause cerebrovascular insult are in 56% located in bulbus, 10% in vertebral arteries, 9% in truncus brachiocephalicus and 9% in art.carotic communis (5, 6) .
According to the literary data and personal experiences as well as during the clinical observation of our patients we noticed that the size of atheromathosis plaques was an important factor for both diagnosis and treatment of those patients. Therefore, we started systematically to examine carotid arteries in patients with the detected coronary disease.

AIM

The aim of our study was to estimate the presence, relations and influence of the plaques on cerebrovascular events

MATERIAL AND METHOD

Our study group had 32 patients, all with angiographically detected coronary disease, 20 males and 12 females, the average age 62 ± 7 years.
Colour Doppler echosonography of the main neck blood vessels on Aquson Sequoa C256 was performed on all our patients using linear transducer of 7 Mhertz and 50 mm deep slices. We examined intraluminal atherosclerotic changes with B mode way, defined intimo-medial thickness over 0,05cm and plaque like focal change of intima bigger than 2mm. Intimo-medial thickness was measured on the posterior wall of common carotid artery and we took 3 measures during diastole. The size of the plaques was determined by Moore's method:

1. minimal arterial ulcerations or irregularities smaller than 10mm²
2. significantly bigger ulcerations area 10 to 40mm²
3. big, unhomogen ulcer, area more than 40mm²

RESULTS

DISCUSSION

The problem of atheromathosis and stenotic lesions of carotid arteries is clinically significant, not only like isolated carotid disease but it is connected with some other diseases which require medicament or surgical treatment (cardiovascular disease, strictly controlled diabetes, big intra abdominal surgery, transplantations, even some orthopaedic procedures) (7, 8).
It is well-known that brain of healthy, young adult has circulation of about 800-1000ml/min.Brain consumes 15 % of volumen, 20%of calories, 20% of blood and about 20% of oxygen consumption.
Brain flow is directly connected with pressure and resistance in blood vessels. Further more, structural changes of vessels and changes in blood viscosity have direct impact on cerebral perfusion although brain is capable of auto regulating mechanisms in orderto keep perfusion on a certain level. Changes of blood pressure, frequency and volumen have direct influence on perfusion of other organs. This is possible due to the permanent accommodation in small cerebral arteries, arteriolas and capilars so, brain flow is last which is compromited in cardial and peripheral circulatory insufficiency.
Serious compromitation of cerebral auto-regulation is present after certain period of unregulated hypertension, prolonged hypotension and acidosys. The loss of cerebral auto regulations is present after 20 minutes of hypoxia, and is re-established after 6-7 hours of regular oxygenation. Brain circulation is constant and doesn't change with changes of systemic blood pressure if its between 60-170 mmHg. Chromnic hypertension is getting auto regulating mechanisms on higher levels.
Moor and his assistant showed a direct correlation between stenosis, size and characteristics of plaques. Therefore, we should identified the risk groups among asymptomatic patients which have stenosis with degeneration of plaques, according to the previous authors. Doppler result is 94 % of the patients sensitive to intrapalqual hemorrhagic, while it is specific in 88%. Embolism from exulcerated plaques brings up the transitor ischemic attack or cerebrovascular insult and if the silent zones of brain are affected it can pass by like clinically unrecognised.
Symptomatic ulcerogened lesion, although homodynamic insignificant is nowadays an absolute indication of endartherectomy (8).
Our results are fully in accordance with the references and states from literature. Therefore, such results make us very confident in our efforts to promote this Moore method as a practical one, not only in routine clinical praxis but in further scientific examinations of coronary disease as well.

CONCLUSION

1. Colour Doppler echosonography of carotid arteries offers detection and estimation of pathoanatomical and pathophysiological changes in carotid arteries of coronary patients.
2. Using Moores method of classification of severity and significance of carotid arteries plaques is important for the evaluation of cerebrovascular sypthomatology and proper treatment.
3. This method is non-invasive, reproducible and should be a part of diagnostic algorithm for every proved coronary patient.

REFERENCES

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3. Consensus Group, Consensus statement on the management of patients with asymptomatic atherosclerotic carotid bifurcation lesions ,International Angiology1995, Vol 14 N0 1-.92-104
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