Coronary Atherosclerosis In Jammu Region - A Random Postmortem Study

Transcription

1 ORIGINAL ARTICLE Coronary Atherosclerosis In Jammu Region - A Random Postmortem Study Sindhu Sharma, Jagriti Singh, P. Angmo, Chavi, K.K. Kaul Abstract Atherosclerosis is a complex and common disease contributing to increased morbidity and mortality in India. Formation of these lesions is preventable through exact health care programs and autopsy study can help in collecting the baseline information. Present study is undertaken to study the prevalence as well as spectrum and distribution of atherosclerotic lesions in the Coronary arteries. Heart specimens were obtained from medico legal autopsies. Sections from representative areas were studied for gross and microscopic evidence of atherosclerosis. Frequency of atherosclerotic lesions in specimens studied (8 males and 8 females) was.%. Atheromatous plaques were observed in.% of male and.89% of female specimens. The significant atheroma appeared in rd decade onwards and gradually increased in frequency and severity up to th decade. The most frequent branches involved were Left Anterior Descending and Right Coronary Artery. Triple vessel disease was seen in 9.8% cases. Autopsy based study of prevalence of Atherosclerotic lesions gives us a fare idea of Coronary artery disease burden in our population. Adequate preventive measures should be instituted as early as third decade of life. Key Words Autopsy, Atherosclerosis/Atheroma, Coronary Arteries Introduction Atherosclerosis is a pathological entity and a multifactorial disease of large and medium sized arteries, characterised by plaque like intimal deposits which contain neutral fats, cholesterol, lipophages, blood elements, at times haemorrhage and calcification. Complications of atherosclerosis are disastrous like- ischaemic heart disease, cerebral stroke, peripheral gangrene and so on (). Global in distribution, atherosclerosis is emerging as the single largest disease accounting for nearly one-third of all deaths in India. An estimated. million Indians died from this in the year. The projected death from Coronary Artery disease by is.9 million, of which % will be < years, % will be < years (). Autopsy is a tool of real value for assessment of pathologies, which are difficult to assess in the living (). As study of atherosclerosis in the living population is difficult, invasive and expensive especially in developing countries, autopsy plays a major role in documenting the prevalence of atherosclerosis in the population (). In view of race, risk factor and geographical diversities present in India, studying the prevalence of this disease in the specific population is of great importance. To the best of our knowledge, very few studies have applied the American Heart Association Classification of Atherosclerosis for assessment of atherosclerosis in Indian population (). Against this background, to assess the magnitude of the problem, a prospective study of autopsied patients for the presence of atherosclerotic lesions of the coronary arteries was undertaken. Thus, the study the prevalence of Atherosclerotic lesions in autopsy specimens of heart and to correlate with age and sex. Also to grade these lesions according to luminal narrowing and American Heart Association Classification. From the Department of Pathology, GMC Jammu. & #Medical Officer, SS Hospital, Jammu- J&K India 8. Correspondence to : Dr. Sindhu Sharma, Department of Pathology, Govt. Medical College Jammu, J&K -india 8 Vol. 8 No., Oct.-Dec

2 Materials and Methods A prospective study was conducted in the Post Graduate Department of Pathology, GMC Jammu for a period of one year approximately i.e. -- to -. It comprised of analysis of specimens of heart obtained from the medicolegal autopsies conducted primarily in the department of Forensic Medicine GMC Jammu as well as in other health care centres of the District. The relevant information regarding the age, sex and apparent cause of death were recorded. The specimens were labelled, numbered, weighed and fixed in % buffered formalin. The heart was then opened by modified Virchow's Method following the direction of blood flow (). A detailed gross examination of the heart specimen was carried out with respect to right and left ventricular wall thickness, interventricular septum thickness, gross examination of the major vessels (aorta, pulmonary artery) and the coronary arteries and their branches for the presence of any fatty streaks, or any obvious macroscopic lesion. After routine processing and paraffin embedding, - micrometer thick paraffin sections were cut, dewaxed and stained with Haematoxylin stain and Eosin stain (). Special stains were performed according to need and nature of lesion. A detailed histopathological examination was carried out for the presence of any atherosclerotic changes and lesions were graded according to the American Heart Association Classification and on the basis of percentage of luminal narrowing (8,9,). Luminal narrowing grades I- Artery appeared grossly normal but had microscopic findings of atherosclerosis with less than % luminal narrowing. II- Thickening of vessel wall with % to less than % of luminal narrowing. III- Thickening of vessel wall with -% narrowing of lumen. IV- Thickening and Calcification with more than % narrowing of lumen. American Heart Association Criteria for Grading Atherosclerotic Lesions - Isolated intimal foamy cells (minimal change). - Numerous intimal foamy cells often in layers (fatty streaks). - Pools of extra cellular lipid without a welldefined core (intermediate lesion or pre-atheroma). - Well defined lipid core with luminal surface covered by normal intima (atheroma or fibroplaque). - Lipid core with a fibrous cap with or without 8 calcification (fibroatheroma). - Fibroatheroma with cap defect such as hemorrhage and thrombosis. - Calcification prominent. 8 - Fibrous tissue change prominent. Appropriate statistical analysis were done wherever necessary. Results Out of specimens of heart studied, one of the specimen was autolysed. The mean weight of the heart was determined to be + gms for males and + gms for females. All the cases were divided into the age groups according to the age at death. Majority of the patients belonged to fifth decade of life (.%) followed by sixth decade (8.9%) and about 8 specimens were of males and of females (Table ). Out of the total hearts studied 8 showed some grade of atherosclerosis of which 8 were males and were females (Table ). Overall prevalence of atherlosclerosis was.%. In our study atheroma were seen above the age of years but significant atheroma appeared after third decade onwards and thereafter a gradual increase in both its frequency and severity from third to sixth decade was seen (Table ). Out of total 8 atheromas, (8.%) were grade, 8 (.8%) each were grade and grade and (.9%) were grade, followed by grade, grade and grade (Table ). Out of the various arteries studied, left anterior descending showed the highest frequency i.e..% followed by left coronary artery (.%) and right coronary artery (.%). Amongst the atherosclerotic coronaries on an average % showed calcification and.% showed aortic involvement (Fig. I, II&III). While considering the percentage luminal narrowing, it was found that cases (.9%) showed III lesions, followed by (.%) showed I, 8 (.8%) showed IV and (.8%) showed II luminal narrowing (Table ). Out of 8 cases in the study triple vessel involvement was most common and seen in (9.8%) cases. The single vessel involvement was seen in (.8%) cases and (.%) cases showed double vessel involvement Table. Prevalence of Coronary Atherosclerosis in Males and Females Atheroma Percentage Male 8 8.% Female.89% 8. Vol. 8 No., Oct.-Dec

3 Table. Number of Vessels Involved in Both Sexes Male Female Percentage Single.8% Double.% Triple 9.8% 8 8 respectively (Table ). Discussion The autopsy study provides a means of understanding the basic process which sets a stage for clinically significant atherosclerotic cardiovascular disease. There is no valid method of sampling living population. It was, therefore, considered that deaths suspected due to cardiovascular pathology, probably provide the best sample of the living population for studying atherosclerosis. Many epidemiological studies have brought to light a number of factors that are of indisputable importance in the development of atherosclerosis (). Atherosclerotic lesions develop very early in life starting from age years onwards. The overall prevalence of atherosclerosis was found to be.8% in the present study which is comparable with frequency frequency of atherosclerosis in third decade (.9%) when compared to second decade (%) and also a steep rise in the frequency of atherosclerosis in fourth decade (.8%). After the fourth decade the frequency rises gradually and maximum incidence was seen in the sixth decade (.%) and thereafter gradual decline was seen. The results of the present study are comparable to those shown by Agravat AH et al and Garg M et al who also observed significant atheroma in the third decade and thereafter increased gradually in both their frequency and severity (,). Earlier studies in India by Wig KL et al found significant atheroma in two-third of cases above age and maximum incidence in sixth decade (89.%) (). Tandon OP et al found atherosclerosis in second and third decade (). The sudden increase of atherosclerotic lesions after second decade may be due to the increased stress, competition, employment and settlement related problems, these age groups have to suffer. All these modifiable life style related risk factors are known to increase the risk of atherosclerosis. In the study out of 8 cases of atherosclerosis, 8 cases (.%) cases were males and cases (.89%) were Fig. Photomicrograph Showing Atheromatous Plaque with percent Luminal Narrowing (H&E, x) Fig.. Frequency Distribution of Involvement of Three Major Arteries Fig. Photomicrograph Showing Calcified Atheromatous plaque with percent luminal narrowing (H&E, x) Left Anterior Descending Artery (LAD) -.% Left Coronary Artery (LCA) -.% Right Coronary Artery (RCA) -.% given by Dhruva GA et al (.%) Golshahi et al (8.9%) and Maru M (%) (,,). It was observed that the degree of atheroma vary in different age groups and in two sexes. Significant atheroma appeared third decade onwards and thereafter there is a gradual increase in both frequency and severity from third decade onwards. The present study showed an abrupt increase in the Vol. 8 No., Oct.-Dec 9

4 Table. Grading of Atherosclerosis in Different Age Groups According to AHA Classification Age Gp U/k %.%.8%.9%.% 8.%.% No. of cases Percentage.%.9%.8% 8.9%.% % % %.8% Table. Age Distribution of Cases According to Luminal Narrowing s Age Gp U/k I 8 II III IV 8 %.%.89%.9%.8% females. This prevalence is comparable with the studies conducted by Golshahi J et al with male female prevalence being 89.% and.8% respectively (). The reason being that males are bread earners and females usually do household work which makes males prone to stress and males also indulge more in smoking and alcoholism. In the present study we have graded atherosclerotic lesions according to two grading systems, one according to American Heart Association Classification of Atherosclerotic Lesions and also according to Luminal Narrowing s (8,9,). It was proposed that these 9 8 lesions progressed from one type to the next. The Plaque rupture is established to be the most significant determinant of thrombus mediated acute coronary syndrome (). The fibroatheromas ( ) was the most common type in our study (8.%), next in frequency were fatty streaks and calcified lesions (.8%) followed by preatheromas i.e. (.9%). Virmani et al in a similar study found out ruptured plaque as the most common type (8). Incidence of Coronary involvement in Left Anterior Descending Artery was (.%), Right Coronary Artery Vol. 8 No., Oct.-Dec

5 . Gamble M,Wilson I. The Hematoxylins and Eosins; Bancroft JD, Gamble M (ed), Theory and Practice of Histological Techniques; th edition; Churchill Livingstone, ;.pp Virmani R. Lessons from sudden coronary death- A comprehensive morphological classification scheme for atherosclerotic lesions. Arterioscler Thromb Vase Biol ; : Stary HC. The histopathological classification of atherosclerotic lesions in Coronary arteries. In: Fuster V, Tpol EJ, eds. Atherosclerosis and Coronary artery disease. Philadelphia: Lippincott-Ravan, 99: 8-.. Stary HC. Natural History and Histological Classification of Atherosclerotic lesions: An update. Arterioscler Thromb Vasc Biol ; ; -8.. Dhruva GA. Atherosclerosis of coronary arteries as predisposing factor in myocardial infarction: An autopsy study. Online J Health Allied Sciences ; (): -.. Golshahi J. Frequency of atherosclerotic lesions in coronary arteries of Autopsy specimens in Isfahan Forensic Medicine Centre. J Research Medical Sciences ; : -9.. Maru M. Coronary Atherosclerosis and myocardial infarction in autopsied patients in Gondar, Ethiopia. JR Soc Med 989; 8 (): Agravat AH. Clinicopathological study of Coronary artery disease. Int Journal Biomedical Advance Research ;: -.. Garg M. Coronary atherosclerosis and myocardial infarction- An Autopsy Study. J Ind Academic Forensic Medicine ; (): 9-.. Wig KL. Prevalence of Coronary atherosclerosis in Northern India. British Med J 9; (): -.. Tandon OP. Coronary and aortic atherosclerosis. Indian Heart J 99; :. Fausto N. Atherosclerosis in young people: The value of the autopsy for studies of the epidemiology and pathobiology of disease. Am J Pathol 998; : Naher S et al. Percentage area of intimal surface of the abdominal aorta affected by atherosclerosis: A post-mortem study. J Med Sci Res ; 9: -. Virmani R. Coronary Heart Disease in 8 autopsy patients years old and younger. Arch Pathol Lab Med 98; (): Thej MJ. Atherosclerosis in Coronary Artery and Aorta in a semi-urban population by applying modified American Heart Association Classification of Atherosclerosis: An Autopsy Study. J Cardiovasc Dis Res ; : -. Sudha ML. Coronary Atherosclerosis in sudden Cardiac Death: An Autopsy study. Ind J Pathol Microbiol 9; (): Yazdi. Prevalence of atherosclerotic plaques in autopsy cases with non cardiac death. Iranian J Pathology 9; (): -. (.%) and Left Coronary Artery (.%). This was in concordance with the data given by Sudha et al who showed Left Anterior Descending Artery as the most common site for plaque (%) and Yazdi et al who showed Left Anterior Descending Artery as the most commonly involved artery (%) followed by Right Coronary Artery (%) and Left Circumflex Artery (.%) (9,). Single vessel involvement was seen in.8% while two vessels and three vessels involvement was seen in.% and 9.8% cases respectively. Three vessel involvements was the most common in our study correlating well with the study of Yezdi et al (). Conclussion In the twenty first century, cardiovascular disease has become a ubiquitous cause of morbidity and a leading contributor to mortality in most countries including India and atherosclerosis is the leading cause of cardiovascular related deaths. Autopsy based studies for evaluating the prevalence of atherosclerosis in a population are cost effective procedures and help in estimating the future disease burden in the population particularly in developing nations like India. In the present study an increased autopsy prevalence of atherosclerosis was found in the males compared to females indicating that preventive measures, screening of cardiovascular risk factors, life style modifications and change of dietary habits should be instituted early in the third decades of young Indians. References. Prabhu MH. Atherosclerosis of Coronary Arteries- an autopsy study. Global J Medical Research Surgeries Cardiovascular System ; (); 9-.. Indrayan A. Forecasting vascular disease cases and associated mortality in India. NCMH Background Papers: Burden of Disease in India. National Commission on Macroeconomics and Health, Government of India. ; Ahmad M. An autopsy study of sudden cardiac death. J Pak Med Ascoc ; (): 9-. Vol. 8 No., Oct.-Dec