Percutaneous Coronary Angioplasty in Diabetes Mellitus: Literature

Diabetes mellitw is a well-loown risk factor for the development of atherosclerotic coronary artery disease. Diabetic patients usually have more extensive and more seyere atherosclerotic disease. PTCA in diabertc patients is associated with high success and low complication rates, afindingwhichis'also confirmedby our own study. Althoughlong term survival is acceptable, diabetic patients may also have a higher rate of infarction and a greater need for additional revascularization procedures, probably because of early restenosis and late progression of coronary artery disease. Diabetes mellins is also associated with progression of coronary artery disease in patients undergoing bypass surgery. The relative merits of PTCA compared to bypass surgery is still not clear. However, a recent report (The Bypass Angbptasty Revascularization Investigation BARI ) indicated that S-year survival was better afier initial treatment with bypass surgery than PTCA. The benefits of newer devices, particularly primary coronary stent implantation, are still being investigated in several sndies. At present, the choice of management strategy is still undetermined and personal preference will play an important part in the decision process. However, medical therapy, with intensive risk factor and liftstyle rnodification, should never be dismissed. This report describes clinical experience with PTCA in the diabeti.c population in Jakarta. The data were derived from1000PTCApatientsofwhoml3lwerediabetics. Angiographicsuccesswasachievedin316of342lesions(92.4Vo)andprocedural successinl18of ljlpartents(90.1Vo). Onepatientunderwentemergencycoronarybypasssurgery,twodevelopedmyocardialinfarction and none died. Our experience showed that PTCA in the diabetics is associated with high success and low major adverse cardiac event rates. The prevalence ofrestenosis was unknown since the majority ofthe patients didnot undergo repeat cardiac catheterizationfor an gio grap hi c follow up. Keyworils : Diabetes mellins, Coronary artery disease, Angioplasty. Division of Cardiobgy, Department of Internal Medicine, University of Indonesia Medical SchooU Dr. Cipn Mangunkuswno Ho spital, Jalcarta, Indonesia Until insulin became available, the association of diabetes with atherosclerosis was virtually unknown. Survival of patients with diabetes before insulin was available was short and death was frequently atVol 6, No 3, JuIy September 1997 uncommon. Since 1920s a large number of studies have identified a high frequency of cardiovascular disease in diabetes and it is well established that coronary artery disease is a major complication of diabetes mellitus. However despite modern treatment the expectation of life of patients with diabetes is still shorter than th without commonest caus patients mellitus is now ic cardiovascular disease. 1'3'4 The main purposes of the present paper are : (a) to review the association of diabetes mellitus and coronary artery disease, (b) to review the results of percutaneous transluminal coronary ( PTCA ) and related procedures in p diabetes mellitus , (c) to review the resul as compared to coronary artery bypass surgery (CABG) in the diaberics, and (d) to present our own experience on PTCA in diabetic patients. Diabetes mellitus and coronary artery disease Much of epidemiological and clinical evidence associating diabetes with atherosclerosis has used as evidence of atherosclerosis clinical syndromes as pectoris, peripheral vascular disease. Although heart failure have also only due to coronary atherosclerosis but appears to be also a result of metabolic abnormalities in the heart muscle itself ( diabetic cardiomyopathy ).s Epidemiological studies confirm that diabetes more than doubles the risk of cardiovascular disease. Diabetes removes the protective effect of the female sex in the development of atherosclerosis. These ef_ fects are independin-t ofthe effects ofother cardiovas_ cular risk factors.6-t J Coronary artery disease is the ultimate cause of death in more.than half of all patients with diabetes mel_ litus.l'3'a Furthermore, myocardial infarction in diabetic patients usually is more extensive and more severe than in nondiabetic patients.14-16 Cardiogenic shocklT and cardiac failurËl8 ur"--o." "o--on io PTCA in Diabetes Mellitus r65 diabetic patients with acute myocardial infarction . The long term survival rate after myocardial infarction among diabetic patients is also lower than that among nondiabetic patiènts.19 In f ct, the 5 year survival rates for diabetic patients after the first major coronary event have been reported to be 3 8 Va and only 25Vo for those with subsequent events, compared with corresponding figures in nond-iabetic patients of 75Vo and 5OVo, respectively.ta'r) An increased prevalence of asymptomatic coronary artery disease ( including : silent myocardial ischemia and silent myocardial infarction ) in diabetic patients seems to be well established. The mechanism is unknown although diabetic autonomic neuropathy seems likely. It is probable that the high frequency of asymptomatic coron ary aftery disease contributes also to the poor prognosis of coronary artery disease in diabetic;.20'2t' Autopsy studies are particularly significant as epidemiological and clinical studies usually rely on less direct methods of diagnosis of atherosclerosis. There is general agreement that coronary atherosclerosis is more severe at all ages and occurs at a younger age in diabetic than in nondiabetic patients. Atherosclerosis in diabetes is not related to the duration of the diabetes, the age of onset of the disease, the blood glucose levels or the type of treatment.22-24 Coronary angiography has also been used to compare the extent of atherosclerosis in diabetic and non_ diabetic patients. The majority of angiographic studies have found that the diabetic patients had an increased number and severity of coronary stenosis, the dif_ ference between diabetic and nondiabetic patients being greater in women than in men.25-28 PTCA and related procedures in diabetes mellitus PTCA is a useful and effective method of revas_ cularization for many patients with atherosclerotic coronary artery disease. With tremendous advances in equipment design, angioplasty techniques, adjunc_ tive procedures ( as coronary stenting, àtherectomy etc. ) and pharmacological agents; PTCA has becomê far safer and more effective over the past 19 years. However, restenosis after pTCA ."màirrs a vexing problem. Because of the prevalence of extensive atherosclerotic disease, diabetics constitute an important segment of the population undergoing pTCA. Stein cs. have recently reported their large population study on the influence of diabetes mellitus on eàrly and