The Indian consensus guidance on stroke prevention in atrial fibrillation: An emphasis on practical use of nonvitamin K oral anticoagulants.

The last ten years have seen rapid strides in the evolution of nonvitamin K oral anticoagulants (NOACs) for stroke prevention in patients with atrial fibrillation (AF). For the preparation of this consensus, a comprehensive literature search was performed and data on available trials, subpopulation analyses, and case reports were analyzed. This Indian consensus document intends to provide guidance on selecting the right NOAC for the right patients by formulating expert opinions based on the available trials and Asian/Indian subpopulation analyses of these trials. A section has been dedicated to the current evidence of NOACs in the Asian population. Practical suggestions have been formulated in the following clinical situations: (i) Dose recommendations of the NOACs in different clinical scenarios; (ii) NOACs in patients with rheumatic heart disease (RHD); (iii) Monitoring anticoagulant effect of the NOACs; (iv) Overdose of NOACs; (v) Antidotes to NOACs; (vi) Treatment of hypertrophic cardiomyopathy (HCM) with AF using NOACs; (vii) NOACs dose in elderly, (viii) Switching between NOACs and vitamin K antagonists (VKA); (ix) Cardioversion or ablation in NOAC-treated patients; (x) Planned/emergency surgical interventions in patients currently on NOACs; (xi) Management of bleeding complications of NOACs; (xii) Management of acute coronary syndrome (ACS) in AF with NOACs; (xiii) Management of acute ischemic stroke while on NOACs.

Transcatheter closure of coronary artery fistulas.

BACKGROUND: Transcatheter closure of coronary artery fistulas has emerged as a successful alternative to surgery. We describe various techniques and short-term findings in 15 patients who were taken up for transcatheter closure of these fistulas. METHODS AND RESULTS: Fifteen patients (aged 2-55 years; 12 males) with coronary artery fistulas underwent percutaneous transcatheter closure between June 1997 and December 2002. Site of origin of these fistulas were: right coronary artery in 7, left anterior descending coronary artery in 4, left main coronary artery in 2 and left circumflex coronary artery in 2 patients. Drainage site of these fistulas were: right ventricle in 9, right atrium in 4 and pulmonary artery in 2 patients. Out of these 15 fistulas, 14 were congenital and one was iatrogenically produced following inadvertent cutting balloon angioplasty of a septal perforator in a patient with chronic total occlusion of left anterior descending coronary artery. Various occlusion devices used to close these fistulas were: conventional metallic coils in 10, floppy tips of coronary angioplasty guidewires in 2, Amplatzer duct occluder in 1 and Amplatzer septal occluder in 2 patients. One of our patients had a coronary artery fistula draining by two openings into the right atrium, both of which were successfully closed using 2 Amplatzer duct occluders. Check angiogram after the procedure revealed complete occlusion in 13 (86.6%) and small residual flow in 2 patients. Follow-up studies at 3-55 months (mean 18 months) showed complete abolition of shunt in all patients with no evidence of recanalization leading to recurrence of shunt. CONCLUSION: Transcatheter closure of coronary artery fistulas is feasible and safe in the anatomically suitable vessels. Use of floppy tips of coronary angioplasty guidewires reduces the cost of the procedure significantly. which is an important consideration in developing countries like India.

Evaluation of Lp[a] and other independent risk factors for CHD in Asian Indians and their USA counterparts.

Conventional risk factors for coronary heart disease (CHD) do not completely account for the observed increase in premature CHD in people from the Indian subcontinent or for Asian Indians who have immigrated to the USA. The objective of this study was to determine the effect of immigration to the USA on plasma levels of lipoprotein [a] (Lp[a]) and other independent risk factors for CHD in Asian Indians. Three subject groups were studied: group 1, 57 subjects living in India and diagnosed with CHD (CHD patients); group 2, 46 subjects living in India and showing no symptoms of CHD (control subjects); group 3, 206 Asian Indians living in the USA. Fasting blood samples were drawn to determine plasma levels of triglyceride (TG), total cholesterol (TC), low density lipoprotein [LDL cholesterol (LDL-Chol)], high density lipoprotein [HDL cholesterol (HDL-Chol)], apolipoprotein B-100 (apoB-100), and Lp[a]. Apolipoprotein [a] (apo[a]) size polymorphism was determined by immunoblotting. Plasma TG, apoB-100, and Lp[a] concentrations were higher in CHD patients than in control and USA groups. CHD patients had higher levels of TC and LDL-Chol and lower HDL-Chol than control subjects. However, the USA population had higher levels of TC, LDL-Chol, and apoB-100 and lower HDL-Chol than control subjects. Plasma Lp[a] levels were inversely correlated with the relative molecular weight of the more abundant of each subject's two apo[a] isoforms (MAI), and CHD patients showed higher frequencies of lower relative molecular weights among MAI. Our observed changes in lipid profiles suggest that immigrating to the USA may place Asian Indians at increased risk for CHD. This study suggests that elevated plasma Lp[a] confers genetic predisposition to CHD in Asian Indians, and nutritional and environmental factors further increase the risk of CHD. This is the first report implicating MAI size as a predictor for development of premature CHD in Asian Indians. Including plasma Lp[a] concentration and apo[a] phenotype in screening procedures may permit early detection and preventive treatment of CHD in this population.

Lipoprotein(a) as an independent risk factor for coronary artery disease in patients below 40 years of age.

Coronary artery disease has assumed alarming proportions in Indians and often affects people at younger age. Traditional risk factors fail to explain the high incidence of disease. Although lipoprotein(a) has been shown to be a powerful risk factor for atherosclerosis, there is very limited data with regard to its significance in premature coronary artery disease. The present study was therefore undertaken to assess lipoprotein(a) levels and its role as a marker of coronary artery disease in patients below the age of 40 years. Lipid profile and lipoprotein(a) levels were estimated in 50 patients of angiographically proven coronary artery disease and an equal number of age-matched healthy controls. There was no significant difference in the family history of coronary artery disease, body mass index and waist-hip ratio between the two groups. Total plasma cholesterol, triglyceride and LDL-cholesterol levels were significantly higher and HDL-cholesterol significantly lower in patients as compared to controls. In patients of coronary artery disease, mean lipoprotein(a) levels, measured by ELISA method, were 35.0 +/- 32.4 mg/dL and the median was 26.7 mg/dL. These values were significantly higher than the mean of 20.3 +/- 17.0 mg/dL (p < 0.002) and the median of 13.8 mg/dL (p < 0.015) in controls. Multiple regression analysis, to assess the influence of various risk factors, showed that low HDL-cholesterol (odds ratio 4.62, 95% CI 1.84-11.60; p < 0.015) and elevated lipoprotein(a) levels (odds ratio 3.06, 95% CI 1.24-7.55; p < 0.001) were independent risk factors, whereas high total cholesterol and triglyceride levels did not have any independent influence on premature coronary artery disease. Our data thus suggest that lipoprotein (a) levels are elevated and constitute an independent risk factor in patients with premature coronary artery disease below 40 years of age.

Treatment of true bifurcation stenosis by elective stent implantation in parent vessel and non-stent dilatation of side branch: immediate and follow-up results.

Data of 67 consecutive patients who underwent stent implantation in the parent vessel and non-stent dilatation of the side branch of a true bifurcation stenosis was retrospectively analysed. The mean age was 53.2 +/- 9.7 years, with majority (89.6%) being males. Forty-seven (70.1%) lesions involved the bifurcation of left anterior descending artery and its major diagonal branch. The parent vessel was treated using balloon angioplasty in 50 (74.6%), rotational atherectomy in 15 (22.4%) and directional coronary atherectomy in 2 (3.0%) patients. All the patients subsequently received an intracoronary stent in the parent vessel. Depending upon the treatment strategy for the side branch, the patients were divided into two groups: (1) Percutaneous transluminal coronary angioplasty group, which included 37 patients in whom the side branch was dilated by plain balloon angioplasty, and (2) Debulking group, in which 30 patients underwent debulking of the side branch using rotablation or directional coronary atherectomy. Overall, the procedure was successful in 64 (95.6%) patients. One (1.5%) patient developed non-Q wave myocardial infarction during the hospital stay. There were no Q-wave myocardial infarction, need for emergency coronary artery bypass surgery or death. Clinical follow-up of at least six months was available in all patients with a mean duration of 9.5 +/- 3.2 months. Recurrence of symptoms developed in 19 (28.4%) patients. Fourteen (20.9%) patients required target vessel revascularisation, of which 11 (29.7%) belonged to the percutaneous transluminal coronary angioplasty group and 3 (10.0%) to the debulking group, the difference being statistically significant (p = 0.045). The freedom from target vessel revascularisation was 93.1 and 89.4 percent at 6 and 12 months in the debulking group, compared to 78.4 and 68.9 percent at the same time in the percutaneous transluminal coronary angioplasty group. This study thus demonstrates that percutaneous intervention for true bifurcation stenosis with stent implantation in the parent vessel and non-stent dilatation in the side branch provides favourable immediate and follow-up results. Debulking in comparison to plain balloon angioplasty of the side branch results in further improvement in clinical outcome and need for target vessel revascularisation on follow-up.

The "hybrid" approach for revascularisation: direct myocardial revascularisation and coronary angioplasty.

We report the cases of two patients where catheter-based laser direct myocardial revascularisation has been coupled with conventional coronary angioplasty at the same sitting using the Biosense left ventricular electromechanically guided laser procedure. In both the cases, the non-revascularizable ischaemic target zone was identified using left ventricular electromechanical mapping signals, and Ho: YAG laser channels were placed at the designated target lesion following successful coronary stenting. The results did not show any procedural complications. This preliminary report suggests the feasibility and safety of this "hybrid" percutaneous approach for myocardial revascularisation.

Silent myocardial ischaemia in patients with type II diabetes mellitus and its relation with autonomic dysfunction.

Accelerated coronary and peripheral vascular atherosclerosis is one of the most common and chronic complications of diabetes mellitus. A relatively recently analysed aspect of coronary artery disease in this condition is its silent or asymptomatic nature. We studied silent/asymptomatic myocardial ischaemia in unselected consecutive middle aged asymptomatic diabetics and controls by 24-hour ambulatory electrocardiographic monitoring, treadmill test and coronary angiography. Also, a relationship was sought between silent myocardial ischaemia and autonomic dysfunction. Thirty asymptomatic diabetics between the ages 35-60 without any documented evidence of coronary artery disease and as many controls (matched for age, sex, smoking habits, blood pressure, serum cholesterol and body mass index) were studied. All the diabetics and controls were subjected to treadmill test and 24-hour ambulatory electrocardiographic monitoring. Coronary angiography was done in those who were positive in treadmill test or 24-hour ambulatory electrocardiographic monitoring. Also five simple bedside tests for autonomic dysfuncton i.e. heart rate response to valsalva, deep breathing and orthostatic variation and blood pressure response to orthostatic variation and sustained handgrip were done in all the subjects. Those with two or more abnormal tests were diagnosed as having autonomic dysfunction. ST segment depression indicating silent myocardial ischaemia was seen in 14 (46.7%) out of 30 diabetics and in 3 (10.0%) out of 30 controls on both Holter and treadmill test (p=0.002). Also, diabetics had higher heart rate and greater number of supraventricular and ventricular ectopics than controls. Coronary angiography done in patients with silent ischaemia revealed higher prevalence of multivessel involvement and diffuse disease in diabetics as compared to controls. Half the diabetics (50%) and none of the control had autonomic dysfunction. Autonomic dysfunction was present in 85.7 percent of diabetics with silent ischaemia compared to 18.7 percent diabetics without silent ischaemia (p=0.001).

Long-term follow-up results after plain balloon coronary angioplasty.

Between September 1987 and June 1992, 571 patients of coronary artery disease underwent percutaneous transluminal coronary angioplasty in our institute. Their ages ranged from 31-82 years (mean 51 +/- 9) and majority (88.3%) were males. At baseline, 318 (55.7%) patients had chronic stable angina, 184 (32.2%) unstable angina, and 57 (10%) underwent PTCA for recurrence of angina in the post-infarction period. Single vessel angioplasty was performed in 406 (71.1%), two-vessel angioplasty in 121 (21.2%) and three or more vessels were dilated in 44 (7.7%). The procedure was successful in 524 (91.8%) patients. Follow-up was available in 438 (83.6%) patients, and ranged from 78 to 135 months (mean 89 +/- 29) with all the patients completing at least 60 months of follow-up. Using Kaplan-Meier statistical analysis, event-free survival (freedom from repeat percutaneous transluminal coronary angioplasty, myocardial infarction, coronary artery bypass surgery, or death) was 72.5 percent at three, 68.0 percent at five, 61.8 percent at seven and 55.6 percent at 10 years of follow-up. Freedom from major adverse cardiac events (myocardial infarction, coronary artery bypass surgery or death) was 88.3, 85.8, 82.0 and 75.4 percent at 3, 5, 7 and 10 years, respectively. Overall survival was 97.4 and 95.2 percent, respectively at 5 and 10 years. Subgroup analysis for all major events was done between males and females, diabetics and non-diabetics, previous history or absence of myocardial infarction, stable versus unstable angina and single versus multivessel disease. Event-free survival rates were compared between the groups using log rank test. On follow-up, the need for surgical revascularisation was more in males compared to females although statistically insignificant, and in patients with unstable angina compared to stable angina (p < 0.02). Similarly, freedom from major adverse cardiac events was significantly better in females compared to males (p < 0.05) and in stable versus unstable angina (p < 0.01). Event-free survival (repeat percutaneous transluminal coronary angioplasty, myocardial infarction, coronary artery bypass surgery, death) was also significantly better in patients with stable angina (p < 0.02). The other outcomes were comparable in all the subgroups. In conclusion, plain balloon angioplasty provides excellent long-term results in patients with coronary artery disease in terms of reduction in major adverse cardiovascular events and need for subsequent revascularisation.