Is increased apolipoprotein B-A major factor enhancing the risk of coronary artery disease in type 2 diabetes?

OBJECTIVES: An association of Apolipoprotein B (Apo B) with coronary artery disease (CAD) independent of LDL cholesterol (LDLc) concentrations has been reported in white population. This analysis was taken up to study whether the higher CAD risk in Asian Indians with diabetes could be explained by possible alterations in Apo B and Apolipoprotein A1 (Apo A1) concentrations. METHODS: The study group consisted of four hundred and forty seven men aged > or = 25 years, 167 with CAD and 280 with no CAD, classified by coronary angiography. Plasma lipid profile including total cholesterol, LDLc, Apo A1 and Apo B were done. Glucose tolerance was evaluated in all. RESULTS: Age, BMI, Apo B, and Apo A1 were significantly associated with CAD in a multiple regression analysis. Hyper Apo B was more common than hyper LDLc in CAD (73.6% vs 20.4%, chi2 = 157, P < 0.001). Apo B concentrations were increased in diabetic subjects even in the presence of normal levels of LDLc and in the absence of CAD. CONCLUSIONS: The study has shown that the apolipoproteins B and A1 provide better information regarding the risk of CAD. Apo B abnormalities exist in large percentages of CAD subjects despite having normal levels of LDLc. Diabetes per se enhances the Apo B concentrations and this could probably be one of the mechanisms of accelerated CAD in diabetes. Hyper Apo B may be an index of CAD risk.

Off-pump versus on-pump CABG: a comparison.

BACKGROUND: The off-pump technique reduces the complications of coronary artery bypass grafting performed with extracorporeal circulatory assistance. This hypothesis was tested by analyzing the results of 53 patients operated with and 48 without cardiopulmonary bypass by a single surgeon (ARR) from February 2001 to September 2001. METHODS AND RESULTS: The angiograms of all the patients scheduled for isolated coronary artery bypass grafting were carefully analyzed and a plan for revascularization made. After sternotomy and inspection of the vessels, a decision was taken to perform the surgery on- or off-pump. All the demographic, operative and postoperative data were prospectively collected and analyzed statistically. Major end-points, such as mortality, perioperative infarction and organ dysfunction, were not different between the two techniques. The incidence of renal and pulmonary dysfunction was similar. There were no neurological problems in either group. In contrast to many reports. bleeding complications and the use of blood products were the same in both groups (1.6+/-2.3 in the on-pump group and 0.8+/-1.7 in off-pump group: p=0.06). The only important difference between the two groups was the incidence of low cardiac output and use of inotropes, being more common in the on-pump group. CONCLUSIONS: Off-pump coronary artery bypass grafting is as safe as that done on-pump. The claims of a lower incidence of organ dysfunction and blood product use in the off-pump group were not substantiated in this study. The incidence of low cardiac output and use of inotropes was significantly lower in the off-pump group.

Surgical repair of left ventricular aneurysms: a comparative evaluation of linear versus Dor's repair.

BACKGROUND: Resection and linear repair of aneurysms of the left ventricle alter its geometry and thereby reduce its performance over the long term. Hence, Dor's circular patch repair was advocated to maintain the geometry of the left ventricle. However, the superiority of this procedure over linear repair is debatable. METHODS AND RESULTS: We retrospectively analyzed 95 cases of left ventricular aneurysm repair--28 cases by Dor's procedure and 67 by linear repair. The age group, symptoms, risk-factor profile and severity of coronary artery disease were comparable in both the groups, but the cardiopulmonary bypass and mean aortic cross-clamp time were longer in those treated with Dor's procedure. The left internal mammary artery could be grafted to the left anterior descending artery or diagonal branch in 13 cases in the group undergoing Dor's procedure (group I) versus 14 cases in the group undergoing linear repair (group II). There was no mortality in group I while there were 7 deaths in group II. Patients in group I were followed up for up to 2 years and those in group II for up to 13 years. During follow-up, 16/2 8 remained in NYHA functional class I or II in group I versus 24/67 in group II. The mean preoperative left ventricular ejection fraction was 34.9% in group I which improved to 39.7% during follow-up. In group II, the mean preoperative left ventricular ejection fraction was 37.2% which improved to 41.5% during follow-up. This difference was not statistically significant. CONCLUSIONS: In our retrospective study, we did not observe any superiority of Dor's repair over linear repair for left ventricular aneurysm as regards NYHA functional class and left ventricular ejection fraction. However, follow-up with Dor's repair was short (up to 2 years). Hence, no definite conclusions can be drawn.

The future of cardiothoracic surgery in India.

The population of India had just crossed one billion mark when we entered the new millennium and open-heart operations were carried out in 42,000 cases last year which is in sharp contrast of 42 operations/million population as compared to 1700/annum/million in USA. Cardiovascular diseases are major contributors to mortality and morbidity in India. Each year between 48,000 and 128,000 children are born in India with congenital heart diseases. In 1999, 6750 operations were done for congenital heart diseases. Though excellent results were achieved, but enough surgeries could not be done. There are more than one million rheumatic heart diseases in India and 50,000 new episodes are added every year. Well over 100,000 valve replacements have taken place during the last two decades. But the cost of valve replacement surgery is beyond common man's reach. There is need to set up an agency to provide heart valves at a subsidised rate. The rapid escalation of coronary heart disease in India is a matter of concern. In 1980, coronary by-pass surgery made up less than 10% of the work that was done by a cardiac surgeon. Today it is more than 60%. At present only 25,000 coronary by-pass operations and 12,000 coronary angioplasty procedures are done in a year. The Human Organs Transplantation Act though passed in 1994, but still only 50 heart transplants have been performed. The past two decades have seen remarkable changes in cardiac surgery in the country. The public hospitals need to be upgraded. The time has come for the MCI to permit joint training programmes between public and private hospitals. As insurance sector has come to the field, so a dramatic growth of health care facilities is expected. Until now, cardiac surgery in our country has developed in an unplanned manner. Progress has been the result of individual initiative. While significant progress has been made, it has not reached the nation's needs. With a planned approach, co-ordinated by IACTS, we can do better.

Techniques and follow-up results of coronary artery by-pass grafting with special reference to Indian subset of patients.

Coronary artery by-pass surgery is fast becoming the most commonly performed major operation even in our country. Coronary heart disease in Indian patients has a lot of peculiarity which distinguishes it from the western population. Indian patients are younger in age, more often diabetic and hyperlipidaemic. Smoking and obesity are not as common as in the west. The coronary arteries are smaller in diameter and are affected diffusely with the atherosclerotic process. These factors make the operation technically more difficult. The techniques have been perfected to a very high level and are being performed in India with results comparable to the western world. The average operative mortality for coronary artery by-pass grafting (CABG) is around 2%.