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Natarajan MK, Velianou JL, Turpie AGG, Mehta SR, Raco D, Goodhart DM, Afzal R, Ginsberg JS. A randomized pilot study of dalteparin versus unfractionated heparin during percutaneous coronary interventions. Am Heart J 2006; 151:175. [PMID: 16368313 DOI: 10.1016/j.ahj.2005.06.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Accepted: 06/09/2005] [Indexed: 01/09/2023]
Abstract
BACKGROUND Direct comparison of low-molecular-weight heparin, dalteparin, with unfractionated heparin (UFH) during percutaneous coronary intervention (PCI) is limited. This study examined the relative effects of dalteparin and UFH on coagulation and angiographic and clinical indices during PCI. METHODS This was a double-blind randomized study, stratified by planned glycoprotein IIb/IIIa inhibitor use. Both UFH and dalteparin were administered as an intra-arterial bolus immediately before PCI. RESULTS All randomized patients received the assigned study drug and underwent PCI. Mean activated clotting time levels were 344 seconds for UFH and 234 seconds for dalteparin (P < .0001). Anti-factor Xa levels were higher for dalteparin at 30 minutes (UFH 1.3 IU/mL vs dalteparin 1.7 IU/mL, P = .005)) and at 4 hours (UFH 0.27 IU/mL vs dalteparin 0.69 IU/mL, P < .0001). Angiographic success was > 90% in both groups, and angiographic complications were similar (UFH 2.5% vs dalteparin 3.8%). The composite of death, myocardial infarction, target vessel revascularization, or bailout glycoprotein IIb/IIIa at hospital discharge was 13.7% in the UFH group and 13.1% in the dalteparin group (P = not significant). There were 2 major bleedings requiring transfusion, both occurring in the UFH group. CONCLUSIONS This study suggests that a single intra-arterial bolus of low-molecular-weight heparin without monitoring is feasible and warrants further investigation as an alternative to UFH during PCI.
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Natarajan MK, Gafni A, Yusuf S. Determining optimal population rates of cardiac catheterization: a phantom alternative? CMAJ 2005; 173:49-52. [PMID: 15997044 PMCID: PMC1167812 DOI: 10.1503/cmaj.050432] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Ahmad M, Schwalm JD, Velianou JL, Natarajan MK. Impact of routine in-hospital assessment of low-density lipoprotein levels and standardized orders on statin therapy in patients undergoing percutaneous coronary interventions. THE JOURNAL OF INVASIVE CARDIOLOGY 2005; 17:518-20. [PMID: 16204743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
BACKGROUND Previous studies have shown that a significant proportion of patients undergoing percutaneous coronary intervention (PCI) are not receiving guideline-recommended statin therapy upon hospital discharge. We evaluated the impact of the implementation of routine cholesterol profile measurements and standardized orders post-PCI on the number of patients receiving statin therapy. METHODS We conducted a prospective, observational study on all patients undergoing PCI in an urban teaching hospital from February 2002 to March 2003. Patient baseline characteristics, statin therapy pre- and post-PCI, and fasting lipid profiles were recorded as part of an ongoing PCI database. A similar cohort of patients undergoing PCI in the one-year time period immediately before the intervention was used as a comparison group. RESULTS A total of 1,748 patients underwent PCI during the study period. Statin therapy was prescribed in 78% of patients pre-PCI and increased to 92% at hospital discharge. In the year before implementation of the standardized post-PCI orders, there was only a 5% absolute increase in statin use after PCI compared to a 14% absolute increase in the study time period (p = < 0.0001). Low-density lipoprotein (LDL) levels were available in 1,268 patients. The median LDL level was 2.08 mmol/L for patients on statin therapy versus 2.40 mmol/L for those not on statins. CONCLUSIONS Routine assessment of LDL levels and lipid-lowering therapy at the time of PCI resulted in a further increase in statin use. However, approximately one-third of patients still had an LDL level above recommended guidelines for secondary prevention.
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Cantor WJ, Puley G, Natarajan MK, Dzavik V, Madan M, Fry A, Kim HH, Velianou JL, Pirani N, Strauss BH, Chisholm RJ. Radial versus femoral access for emergent percutaneous coronary intervention with adjunct glycoprotein IIb/IIIa inhibition in acute myocardial infarction--the RADIAL-AMI pilot randomized trial. Am Heart J 2005; 150:543-9. [PMID: 16169338 DOI: 10.1016/j.ahj.2004.10.043] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2004] [Accepted: 10/18/2004] [Indexed: 02/07/2023]
Abstract
BACKGROUND Transradial percutaneous coronary intervention (PCI) results in fewer vascular complications, earlier ambulation, and improved patient comfort. Limited data exist for radial access in acute myocardial infarction, where reperfusion must occur quickly. METHODS In a multicenter pilot trial, 50 patients with myocardial infarction requiring either primary or rescue PCI were randomized to radial or femoral access. All operators had previously performed at least 100 transradial cases. Procedure times were prospectively recorded. RESULTS Thrombolysis was used in 66% of the cases and glycoprotein IIb/IIIa inhibitors in 94%. Crossover from radial to femoral access was required in one case. Percutaneous coronary intervention was performed in 47 patients, with stenting in 45. One procedural failure occurred with radial access because of inability to cross the occlusion. The time from local anesthesia to first balloon inflation was 32 (25th percentile 26, 75th percentile 38) minutes for radial access and 26 (22, 33) minutes for femoral access (P = .04). There were no significant differences in contrast use or fluoroscopy time. No patient experienced major bleeding or required transfusion. Doppler studies demonstrated 2 asymptomatic radial occlusions and 2 pseudoaneurysms (1 from each group). One patient in the femoral group died 2 days after PCI. At 30 days, there were no strokes or reinfarctions and no patient required bypass surgery or repeat PCI. CONCLUSIONS Primary and rescue PCI can be performed with high success rates using either radial or femoral access. Although radial access was associated with a longer time to first balloon inflation, the difference was small and likely not clinically significant. In patients without shock, major bleeding and vascular complications are infrequent with either access site despite the high use of thrombolysis and glycoprotein IIb/IIIa inhibitors.
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Mehta SR, Steg PG, Granger CB, Bassand JP, Faxon DP, Weitz JI, Afzal R, Rush B, Peters RJG, Natarajan MK, Velianou JL, Goodhart DM, Labinaz M, Tanguay JF, Fox KAA, Yusuf S. Randomized, Blinded Trial Comparing Fondaparinux With Unfractionated Heparin in Patients Undergoing Contemporary Percutaneous Coronary Intervention. Circulation 2005; 111:1390-7. [PMID: 15781750 DOI: 10.1161/01.cir.0000158485.70761.67] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Factor Xa plays a central role in the generation of thrombin, making it a novel target for treatment of arterial thrombosis. Fondaparinux is a synthetic factor Xa inhibitor that has been shown to be superior to standard therapies for the prevention of venous thrombosis. We performed a randomized trial to determine the safety and feasibility of fondaparinux in the percutaneous coronary intervention (PCI) setting.
Methods and Results—
A total of 350 patients undergoing elective or urgent PCI were randomized in a blinded manner to receive unfractionated heparin (UFH), 2.5 mg fondaparinux IV, or 5.0 mg fondaparinux IV. Randomization was stratified for planned or no planned use of glycoprotein (GP) IIb/IIIa antagonists. The primary safety outcome was total bleeding, which was a combination of major and minor bleeding events. The incidence of total bleeding was 7.7% in the UFH group and 6.4% in the combined fondaparinux groups (hazard ratio, 0.81; 95% confidence interval, 0.35 to 1.84;
P
=0.61). Bleeding was less common in the 2.5-mg fondaparinux group compared with the 5-mg fondaparinux group (3.4% versus 9.6%,
P
=0.06). The composite efficacy outcome of all-cause mortality, myocardial infarction, urgent revascularization, or need for a bailout GPIIb/IIIa antagonist was 6.0% in the UFH group and 6.0% in the fondaparinux group, with no significant difference in efficacy among the fondaparinux doses compared with UFH. Coagulation marker analysis at 6 and 12 hours after PCI demonstrated that fondaparinux was superior to UFH in inducing a sustained reduction in markers of thrombin generation, as measured by prothrombin fragment F1.2 (
P
=0.02).
Conclusions—
In this pilot study of patients undergoing contemporary PCI, factor Xa inhibition with the synthetic anticoagulant fondaparinux in doses of 2.5 and 5.0 mg was comparable to UFH for clinical safety and efficacy outcomes. These data form the basis for further evaluation of fondaparinux in arterial thrombosis.
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Madan M, Labinaz M, Cohen EA, Buller CE, Cantor WJ, Seidelin P, Ducas J, Carere RG, Natarajan MK, Pieper KS, Hafley GE, O'Shea JC, Kitt MM, Califf RM, Tcheng JE. A comparison of clinical outcomes between Canadian and American patients after nonurgent coronary stenting. Can J Cardiol 2004; 20:1343-9. [PMID: 15570357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
BACKGROUND Practice patterns for percutaneous coronary interventions (PCIs) may differ between Canada and the United States. Few data are available comparing PCI outcomes between the two countries in the era of coronary stenting and adjunctive glycoprotein IIb/IIIa inhibition. METHODS In the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial, 2064 patients were randomly assigned to receive eptifibatide or placebo during nonurgent PCI. The 30-day and one-year rates of death, myocardial infarction (MI) and target vessel revascularization (TVR) were compared between Canadian and American patients enrolled in the ESPRIT trial. RESULTS There were 1531 American patients and 533 Canadian patients enrolled. Americans were older and heavier, and had a higher incidence of cardiac risk factors than Canadians (P<0.05 for all variables). Canadian patients had a lower incidence of death, MI and TVR at 30 days (6.2% versus 10.4%, P=0.004) and at one year (14.8% versus 21.5%, P=0.0006). After adjusting for known baseline differences, enrollment in Canada remained a significant predictor of reduced ischemic complications at 30 days (OR=0.53, c2=9.0, P=0.003). Similar results were observed at one year. Eptifibatide was superior to placebo in both groups of patients. CONCLUSIONS This analysis is among the first to show Canadian patients to have fewer adverse events than American patients after nonurgent PCI. This effect was independent of known baseline differences between the patients in each country. The relative treatment effect of eptifibatide in Canadian patients paralleled that observed in the main ESPRIT trial and in American patients.
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Segev A, Kassam S, Buller CE, Lau HK, Sparkes JD, Connelly PW, Seidelin PH, Natarajan MK, Cohen EA, Strauss BH. Pre-procedural plasma levels of C-reactive protein and interleukin-6 do not predict late coronary angiographic restenosis after elective stenting. Eur Heart J 2004; 25:1029-35. [PMID: 15191773 DOI: 10.1016/j.ehj.2004.04.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2003] [Revised: 03/23/2004] [Accepted: 04/29/2004] [Indexed: 11/13/2022] Open
Abstract
AIMS Inflammatory markers may serve as an important prognostic predictor in patients with coronary heart diseases. In patients undergoing coronary interventions, it has been shown that baseline C-reactive protein (CRP) could predict late clinical restenosis. Only a few small studies have examined the possible relationship with angiographic restenosis. In patients with stable angina pectoris,we examined whether baseline CRP and IL-6 predict late coronary angiographic restenosis after stenting. METHODS AND RESULTS Pre-procedural plasma levels of CRP and IL-6 were measured in 216 patients with stable angina pectoris undergoing elective coronary stenting. Angiographic follow-up was performed in all patients at 6 months. Baseline CRP levels were 6.15 +/- 0.78 mg/L versus 5.24 +/- 1.17 mg/L in the patent and restenosis groups, respectively (P=0.64). IL-6 levels were 0.46 +/- 0.03 ng/L versus 0.40 +/- 0.07 ng/L in the patent and restenosis groups, respectively (P=0.50). CRP levels were obtained again at the time of angiographic follow-up and were found to be similar in both groups (2.89 +/- 0.29 mg/L versus 2.61 +/- 0.63 mg/L, P=0.72). Moreover, in a sub-group of 43 patients, serial blood samples were obtained at several time points after the procedure up to 6 months. Both CRP and IL-6 plasma levels increased significantly in response to the procedure. CRP levels peaked at 3 days (11.27 +/- 1.53 mg/L versus 4.26 +/- 0.72 mg/L at baseline, P<0.0001). IL-6 levels reached maximum values after 24 h (1.08 +/- 0.14 ng/L versus 0.53 +/- 0.08 ng/L at baseline, P<0.0001). However, in this sub-group of patients, neither peak CRP nor IL-6 levels were found to predict late angiographic restenosis. CONCLUSIONS Coronary stenting is associated with transient increases in both CRP and IL-6 levels. However, pre-procedural CRP and IL-6 levels do not predict late coronary angiographic restenosis.
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Segev A, Cantor WJ, Cohen EA, Seidelin PH, Natarajan MK, Marquis JF, Lazzam C, Watson RK, Chisholm RJ, Strauss BH. Low Rates of Angiographic and Clinical Restenosis with the New Flexible MedStent for the Treatment of Single Discrete Coronary Lesions. J Interv Cardiol 2004; 17:167-70. [PMID: 15209579 DOI: 10.1111/j.1540-8183.2004.09881.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The use of enhanced designs of new coronary stents continues to expand the spectrum of coronary anatomy and clinical settings amenable to nonsurgical revascularization. The objectives of this clinical trial were to demonstrate the safety and late angiographic restenosis rate of the new flexible MedStent. The study included 117 patients with stable or unstable angina pectoris and a discrete de novo lesion of a native coronary artery. Procedural success, 6-month angiographic findings, and 1-year clinical outcomes were determined. The stent was successfully deployed in all but one patient (99.1%). There were no events in any of the patients within the first 2 weeks after the procedure. At 1 year, a total of 12 patients had 16 clinical events related to the stented artery (1 death, 3 non-Q-wave MIs, 10 repeat PTCAs, and 2 CABG procedures). This represents a target vessel revascularization rate (TVR) of 10.3%. The minimal luminal diameter (MLD) at 6 months for the MedStent was 2.04 +/- 0.71 mm. The 6-month binary angiographic restenosis was 20.0% (95% CI, 12.5%-27.5%). The results of the Medstent study in discrete, de novo native coronary lesions demonstrated low incidence of clinical events as well as favorable angiographic restenosis rate.
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Natarajan MK, Kreatsoulas C, Velianou JL, Mehta SR, Pericak D, Goodhart DM. Incidence, predictors, and clinical significance of troponin-I elevation without creatine kinase elevation following percutaneous coronary interventions. Am J Cardiol 2004; 93:750-3. [PMID: 15019884 DOI: 10.1016/j.amjcard.2003.11.069] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Revised: 11/17/2003] [Accepted: 11/17/2003] [Indexed: 01/29/2023]
Abstract
The objectives of this study were to investigate the incidence, predictors, and clinical significance of isolated postprocedural troponin-I elevations in a consecutive series of patients who underwent percutaneous coronary intervention. We observed, in a series of 1,128 patients, that isolated troponin-I elevations without concomitant creatine kinase elevations occurred in 17% of patients after percutaneous coronary intervention, and that even troponin-I elevations 5 times above the upper limit of normal did not predict events after hospital discharge.
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Segev A, Kassam S, Buller CE, Lau HK, Sparkes JD, Connelly PW, Seidelin PH, Natarajan MK, Cohen EA, Strauss BH. 1121-48 Preprocedural plasma levels of C-reactive protein and interleukin-6 do not predict late coronary angiographic restenosis after elective stenting. J Am Coll Cardiol 2004. [DOI: 10.1016/s0735-1097(04)90319-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Natarajan MK, Yusuf S. Primary angioplasty for ST-segment elevation myocardial infarction: ready for prime time? CMAJ 2003; 169:32-5. [PMID: 12847037 PMCID: PMC164940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
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Natarajan MK, Mehta SR, Holder DH, Goodhart DR, Gafni A, Shilton D, Afzal R, Teo K, Yusuf S. The risks of waiting for cardiac catheterization: a prospective study. CMAJ 2002; 167:1233-40. [PMID: 12451076 PMCID: PMC134132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
Abstract
BACKGROUND Few large, systematic, prospective studies have documented the characteristics and clinical outcomes of patients awaiting cardiac catheterization and the delays that they experience. The primary objective of this study was to quantify the waiting times, morbidity and mortality of patients waiting for catheterization. A secondary objective was to identify predictors of cardiac events that occur while patients are waiting. METHODS A computerized, prospective, central waiting list registry was developed at a regional centre in Hamilton, Ont., serving 2.2 million people in southern Ontario. Between Apr. 1, 1998, and Mar. 31, 2000, 8030 consecutive patients (4725 outpatients and 3305 inpatients) were referred for cardiac catheterization. Major cardiac outcomes while on the waiting list (death, myocardial infarction and congestive heart failure) were documented prospectively and related to requested versus actual waiting time. RESULTS Most of the referrals (7345 [91.5%]) were for a primary diagnosis of suspected coronary artery disease. The median waiting time was 6 (interquartile range [IQR] 4) days for inpatients and 60 (IQR 68) days for outpatients. Actual waiting times correlated with the waiting times requested by the referring physicians. However, only 37% of the procedures overall were completed within the requested waiting time. Of the 8030 patients, 50 (0.6%) died, 32 (0.4%) had a myocardial infarction and 41 (0.5%) experienced congestive heart failure. Overall, 109 patients (1.4%) had a major cardiac event, namely, death, myocardial infarction or congestive heart failure. These events occurred over a median wait of 27 days (2 days for inpatients and 35 days for outpatients), and over half (57%) occurred within the waiting time requested by the referring physician. In the multivariate analysis, predictors of the composite of death, myocardial infarction or congestive heart failure were increasing age (relative risk [RR] 2.39, 95% confidence interval [CI] 1.52-3.75) and New York Heart Association class III/IV symptoms (RR 2.86, 95% CI 1.11-7.33) in inpatients, and increasing age (RR 1.36, 95% CI 1.12-1.66), aortic stenosis (RR 3.70, 95% CI 1.93-7.08) and left ventricular ejection fraction less than 35% (RR 4.35, 95% CI 2.48-7.61) in outpatients. INTERPRETATION Patients awaiting cardiac catheterization may experience major adverse events, such as death, myocardial infarction and congestive heart failure, which may be preventable. Our findings provide a benchmark by which to measure the effect of increased capacity and prioritization schemes that allow earlier access for patients at higher risk, such as those with aortic stenosis and reduced left ventricular function.
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Mehta SR, Eikelboom JW, Rupprecht HJ, Lewis BS, Natarajan MK, Yi C, Pogue J, Yusuf S. Efficacy of hirudin in reducing cardiovascular events in patients with acute coronary syndrome undergoing early percutaneous coronary intervention. Eur Heart J 2002; 23:117-23. [PMID: 11785993 DOI: 10.1053/euhj.2001.2731] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIMS Although hirudin is superior to unfractionated heparin for prevention of death, myocardial infarction, or refractory ischaemia in patients with non-ST-elevation acute coronary syndrome, it is not clear whether hirudin is also of benefit in acute coronary syndrome patients undergoing early percutaneous coronary intervention. METHODS AND RESULTS In the OASIS 2 trial, 10 141 patients with non-ST-elevation acute coronary syndrome were randomized to 72 h of intravenous hirudin or unfractionated heparin. Percutaneous coronary intervention was performed at the discretion of the investigator. One hundred and seventeen patients underwent percutaneous coronary intervention within the first 72 h ("early percutaneous coronary intervention"). In patients undergoing early percutaneous coronary intervention, hirudin compared with unfractionated heparin was associated with a significantly lower incidence of death or myocardial infarction at 96 h (6.4% vs 21.4%, OR 0.30; 95% CI: 0.10-0.88) and 35 days (6.4% vs 22.9%, OR 0.25; 95% CI: 0.07-0.86). In the unfractionated heparin group, death or myocardial infarction was significantly higher at 35 days in patients undergoing early percutaneous coronary intervention compared with those managed conservatively (22.9% vs 7.3%, OR 3.14, P<0.001) but this early percutaneous coronary intervention-related hazard was not observed in hirudin-treated patients (6.4% vs 6.8%, OR 0.94 P=1.0). A time-dependent covariate for percutaneous coronary intervention was not significant in a Cox regression model, suggesting a similar treatment benefit with hirudin before and after percutaneous coronary intervention. After adjustment for percutaneous coronary intervention propensity, the benefits of hirudin remained significant. There were three major bleeds in patients undergoing early percutaneous coronary intervention, all in patients randomized to hirudin. CONCLUSION In patients with non-ST-elevation acute coronary syndrome undergoing early percutaneous coronary intervention, a direct thrombin inhibitor such as hirudin may be more effective than heparin in reducing the incidence of ischaemic complications.
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Mehta SR, Yusuf S, Peters RJ, Bertrand ME, Lewis BS, Natarajan MK, Malmberg K, Rupprecht H, Zhao F, Chrolavicius S, Copland I, Fox KA. Effects of pretreatment with clopidogrel and aspirin followed by long-term therapy in patients undergoing percutaneous coronary intervention: the PCI-CURE study. Lancet 2001; 358:527-33. [PMID: 11520521 DOI: 10.1016/s0140-6736(01)05701-4] [Citation(s) in RCA: 2177] [Impact Index Per Article: 94.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Despite the use of aspirin, there is still a risk of ischaemic events after percutaneous coronary intervention (PCI). We aimed to find out whether, in addition to aspirin, pretreatment with clopidogrel followed by long-term therapy after PCI is superior to a strategy of no pretreatment and short-term therapy for only 4 weeks after PCI. METHODS 2658 patients with non-ST-elevation acute coronary syndrome undergoing PCI in the CURE study had been randomly assigned double-blind treatment with clopidogrel (n=1313) or placebo (n=1345). Patients were pretreated with aspirin and study drug for a median of 6 days before PCI during the initial hospital admission, and for a median of 10 days overall. After PCI, most patients (>80%) in both groups received open-label thienopyridine for about 4 weeks, after which study drug was restarted for a mean of 8 months. The primary endpoint was a composite of cardiovascular death, myocardial infarction, or urgent target-vessel revascularisation within 30 days of PCI. The main analysis was by intention to treat. FINDINGS There were no drop-outs. 59 (4.5%) patients in the clopidogrel group had the primary endpoint, compared with 86 (6.4%) in the placebo group (relative risk 0.70 [95% CI 0.50-0.97], p=0.03). Long-term administration of clopidogrel after PCI was associated with a lower rate of cardiovascular death, myocardial infarction, or any revascularisation (p=0.03), and of cardiovascular death or myocardial infarction (p=0.047). Overall (including events before and after PCI) there was a 31% reduction cardiovascular death or myocardial infarction (p=0.002). There was less use of glycoprotein IIb/IIIa inhibitor in the clopidogrel group (p=0.001). At follow-up, there was no significant difference in major bleeding between the groups (p=0.64). INTERPRETATION In patients with acute coronary syndrome receiving aspirin, a strategy of clopidogrel pretreatment followed by long-term therapy is beneficial in reducing major cardiovascular events, compared with placebo.
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Barolet AW, Nili N, Cheema A, Robinson R, Natarajan MK, O'Blenes S, Li J, Eskandarian MR, Sparkes J, Rabinovitch M, Strauss BH. Arterial elastase activity after balloon angioplasty and effects of elafin, an elastase inhibitor. Arterioscler Thromb Vasc Biol 2001; 21:1269-74. [PMID: 11498452 DOI: 10.1161/hq0801.093589] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Increased proteolytic activity may be a factor in intimal hyperplasia after balloon angioplasty (BA). The objectives of this study were to assess elastase activity after BA in a rabbit arterial double-injury model and the effects of elastase inhibition. Elastase activity increased immediately after BA, reached an 8-fold peak at 1 week, and declined to baseline levels by 4 weeks. Elastin zymography showed that the elastase activity was associated predominantly with a molecular mass of 25 kDa. Elastase activity was significantly inhibited in vitro by elafin and phenylmethylsulfonyl fluoride, selective inhibitors of serine elastases. A second group of animals was transfected after BA with a plasmid containing the cDNA for either elafin or a control (chloramphenicol acetyltransferase, CAT) construct by using a hemagglutinating virus of Japan-liposome transfection technique. Arterial segments were obtained at 48 hours, 1 week, and 4 weeks to assess transgene expression, arterial wall elastase activity, and intimal cross-sectional area, respectively. Elafin transgene expression was evident at 48 hours and resulted in a significant (80%) inhibition of elastase activity compared with chloramphenicol acetyltransferase-transfected arteries. There was a 43% reduction in intimal cross-sectional area in elafin-transfected arteries (0.28+/-0.22 versus 0.16+/-0.07 mm(2) for CAT-transfected versus elafin-transfected arteries, respectively; P<0.05). These data suggest that an early increase in serine elastase activity after BA contributes to intimal hyperplasia. Serine elastase inhibition may be a potential therapeutic approach to inhibit intimal hyperplasia.
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Bhattacharya S, Kanungo R, Natarajan MK, Mahalakshmi VN, Srinivasan K. Unimicrobial appendicitis due to non-vaccine serotype of streptococcus pneumoniae: Implications for and management and prevention. Indian J Med Microbiol 2001; 19:59-61. [PMID: 17664810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The aetiology of appendicitis is usually polymicrobial. We report a rare case of appendicitis caused by Streptococcus pneumoniae as the only causative organism. The case assumes significance because it occurs in the absence of any predisposing factor for invasive pneumococcal infection, it is unimicrobial, it may lead to the misdiagnosis of primary peritonitis due to pneumococcus, and it undermines the efficacy of polyvalent pneumococcal vaccine.
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Bhattacharya S, Kanungo R, Natarajan MK, Mahalakshmi VN, Srinivasan K. UNIMICROBIAL APPENDICITIS DUE TO NON-VACCINE SEROTYPE OF STREPTOCOCCUS PNEUMONIAE: IMPLICATIONS FOR AND MANAGEMENT AND PREVENTION. Indian J Med Microbiol 2001. [DOI: 10.1016/s0255-0857(21)03375-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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118
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Jong P, Cohen EA, Batchelor W, Lazzam C, Kreatsoulas C, Natarajan MK, Strauss BH. Bleeding risks with abciximab after full-dose thrombolysis in rescue or urgent angioplasty for acute myocardial infarction. Am Heart J 2001; 141:218-25. [PMID: 11174335 DOI: 10.1067/mhj.2001.112239] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND The bleeding risk associated with platelet glycoprotein IIb/IIIa inhibition in patients undergoing percutaneous transluminal coronary angioplasty (PTCA) after full-dose thrombolysis for acute myocardial infarction (AMI) is unclear. We examined the risk and predictors of bleeding complications in patients with AMI who received abciximab during rescue or urgent PTCA after full-dose thrombolytic therapy. METHODS A multicenter retrospective cohort of 147 consecutive patients who underwent PTCA within 48 hours after full-dose thrombolysis for AMI was studied. Bleeding events (major, minor, nuisance) from the onset of AMI to discharge were compared between those who received abciximab (n = 57) and those who did not (n = 90). RESULTS Baseline clinical characteristics were similar between the two groups. Despite lower doses of procedural heparin, the incidence of non-coronary artery bypass graft-related major and minor bleeding was higher in the abciximab group than in controls (63% vs 39%, P =.004). Although the risk of major bleeding was 4-fold with abciximab (12% vs 3%, P =.04), only one intracranial and one fatal bleeding event occurred. Multivariable regression identified abciximab therapy as the most powerful independent predictor of combined major and minor bleeding, with a hazard risk ratio of 1.9 (P =.04). CONCLUSIONS In the setting of rescue or urgent PTCA within 48 hours after full-dose thrombolytic therapy after AMI, major and particularly minor bleeding were frequently encountered. The adjunctive use of abciximab increased these bleeding risks by approximately 2-fold.
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Mehta SR, Eikelboom JW, Natarajan MK, Diaz R, Yi C, Gibbons RJ, Yusuf S. Impact of right ventricular involvement on mortality and morbidity in patients with inferior myocardial infarction. J Am Coll Cardiol 2001; 37:37-43. [PMID: 11153770 DOI: 10.1016/s0735-1097(00)01089-5] [Citation(s) in RCA: 250] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVES We sought to evaluate the prognostic impact of right ventricular (RV) myocardial involvement in patients with inferior myocardial infarction (MI). BACKGROUND There is uncertainty regarding the risk of major complications in patients with inferior MI complicated by RV myocardial involvement. Whether these complications are related to RV myocardial involvement itself or simply to the extent of infarction involving the left ventricle (LV) is also unknown. METHODS We examined the incidence of death and mechanical and electrical complications in patients with (n = 491) and without (n = 638) RV myocardial involvement and in patients with anterior MI (n = 971) in an analysis from the Collaborative Organization for RheothRx Evaluation (CORE) trial. Left ventricular infarct size was assessed by technetium-99m-sestamibi single-photon emission computed tomography and peak creatine kinase, and LV function was assessed by radionuclide angiography. We also performed a meta-analysis in which we pooled the results of our study with previous smaller studies addressing the same question. RESULTS Six-month mortality was 7.8% in inferior MI compared with 13.2% in anterior MI. Among patients with inferior MI, serious arrhythmias were significantly more common in patients with RV myocardial involvement who also had a trend toward higher mortality, pump failure and mechanical complications. However, this was not associated with a difference in LV infarct size or function. A meta-analysis of six studies (n = 1,198) confirmed that RV myocardial involvement was associated with an increased risk of death (odds ratio [OR] 3.2, 95% confidence interval [CI] 2.4 to 4.1), shock (OR 3.2, 95% CI 2.4 to 3.5), ventricular tachycardia or fibrillation (OR 2.7, 95% CI 2.1 to 3.5) and atrioventricular block (OR 3.4, 95% CI 2.7 to 4.2). CONCLUSIONS Patients with inferior MI who also have RV myocardial involvement are at increased risk of death, shock and arrhythmias. This increased risk is related to the presence of RV myocardial involvement itself rather than the extent of LV myocardial damage.
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MESH Headings
- Arrhythmias, Cardiac/diagnosis
- Arrhythmias, Cardiac/drug therapy
- Arrhythmias, Cardiac/mortality
- Double-Blind Method
- Female
- Hospital Mortality
- Humans
- Male
- Middle Aged
- Myocardial Infarction/diagnosis
- Myocardial Infarction/drug therapy
- Myocardial Infarction/mortality
- Poloxamer/therapeutic use
- Prognosis
- Radionuclide Angiography
- Risk
- Shock, Cardiogenic/diagnosis
- Shock, Cardiogenic/drug therapy
- Shock, Cardiogenic/mortality
- Survival Analysis
- Tomography, Emission-Computed, Single-Photon
- Ventricular Dysfunction, Left/diagnosis
- Ventricular Dysfunction, Left/drug therapy
- Ventricular Dysfunction, Left/mortality
- Ventricular Dysfunction, Right/diagnosis
- Ventricular Dysfunction, Right/drug therapy
- Ventricular Dysfunction, Right/mortality
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Velianou JL, Strauss BH, Kreatsoulas C, Pericak D, Natarajan MK. Evaluation of the role of abciximab (Reopro) as a rescue agent during percutaneous coronary interventions: in-hospital and six-month outcomes. Catheter Cardiovasc Interv 2000; 51:138-44. [PMID: 11025564 DOI: 10.1002/1522-726x(200010)51:2<138::aid-ccd2>3.0.co;2-u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Abciximab is effective for the prevention of complications when administered prior to percutaneous coronary intervention (PCI). The efficacy and safety of abciximab as an unplanned or rescue agent for complications of PCI is unknown. Rescue versus planned use was compared in 186 consecutive patients. Primary or rescue PCI for acute myocardial infarction (MI) and shock were excluded. Rescue abciximab use was undertaken in 101 patients (54.3%) and planned abciximab was used in 85 (45.7%). The rescue abciximab patients had a lower incidence of previous MI, preprocedural thrombus, multivessel, and vein graft intervention. In-hospital endpoints in the rescue versus planned abciximab patients were death (1.0% vs. 1. 2%, P = 1.0), Q-wave MI (2.0% vs. 2.4%, P = 1.0), any MI (14.9% vs. 9.4%, P = 0.3), target vessel revascularization (TVR; 0% vs. 1.2%, P = 1.0), and composite (15.8% vs. 10.6%, P = 0.3). At 6 months, events were death (4.0% vs. 2.3%, P = 0.69), MI (14.9% vs. 9.4%, P = 0.26), TVR (20.8% vs. 4.7%, P = 0.001), and composite (30.7% vs. 15. 3%, P = 0.01). In-hospital complications between the rescue and planned abciximab patients of major bleed (1.0% vs. 1.8%, P = NS), stroke (0% vs. 1.8%, P = NS), and thrombocytopenia (3.0% vs. 1.8%, P = NS) were similar. There was a significantly higher procedural time (99.6 min vs. 86.1 min, P = 0.02), contrast volume (278.8 ml vs. 223. 5 ml, P = 0.04), and heparin use (8984 u vs. 6003 u, P = 0.0006) in the rescue group. In this nonrandomized comparison, rescue abciximab allowed for the safe discharge from hospital in the majority of patients. However, during a 6-month follow-up, more patients treated with rescue abciximab required TVR with either repeat PCI or CABG. Further studies are warranted to evaluate the overall strategy of rescue abciximab use in PCI.
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Kanungo R, d'Lima D, Rajalakshmi B, Natarajan MK, Badrinath S. Throat carriage of pneumococci in healthy school children in the Union Territory of Pondicherry. Indian J Med Res 2000; 112:100-3. [PMID: 11094855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
BACKGROUND & OBJECTIVES Colonisation of Streptococcus pneumoniae in the throat is common among children the world over. Little is known about the relationship of nasopharyngeal carriage and invasive disease or the way it spreads within the households and close confines. There is a paucity of data on the colonization of Strep. pneumoniae in the throat of healthy children in India. To determine the prevalence of pneumococcal carriage in school children of urban and rural Pondicherry, a study was undertaken. METHODS Throat swabs of healthy school-going children between 5-10 yr of age were examined for pneumococcal carriage, by standard bacteriological techniques. RESULTS A prevalence rate of 24.3 per cent was noted. There was no difference in the carriage rate among the rural children when compared to urban children. No age, sex or geographical predilection of pneumococcal carriage was noted. A statistically significant seasonal variation, however, was seen. Carriage rate increased during the colder months and was found to be the highest in the months of March and November. INTERPRETATION & CONCLUSIONS Strep. pneumoniae circulates in the community among healthy children. Carriage rate is influenced by seasonal variation.
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Strauss BH, Lau HK, Bowman KA, Sparkes J, Chisholm RJ, Garvey MB, Fenkell LL, Natarajan MK, Singh I, Teitel JM. Plasma urokinase antigen and plasminogen activator inhibitor-1 antigen levels predict angiographic coronary restenosis. Circulation 1999; 100:1616-22. [PMID: 10517732 DOI: 10.1161/01.cir.100.15.1616] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The fibrinolytic system is intimately involved in several processes that contribute to restenosis, including clot dissolution, cell migration, and tissue remodeling. However, the role of the individual activators (urokinase [uPA] and tissue plasminogen [tPA] activators) and inhibitors (plasminogen activator inhibitor [PAI-1]) of the fibrinolytic system in maintaining patency after coronary artery angioplasty and stenting is unclear. METHODS AND RESULTS We prospectively studied 159 patients with stable angina who underwent successful elective angioplasty (n=110) or stenting (n=49) of de novo native coronary artery lesions. Plasma samples were drawn at baseline (before angioplasty) and serially after angioplasty (immediately afterward and 6 hours, 24 hours, 3 days, 7 days, 1 month, 3 months, and 6 months afterward). Antigen and activity assays were performed for uPA, tPA, and PAI-1. Follow-up quantitative coronary angiography was performed in 92% of eligible patients. The overall angiographic restenosis rate (diameter stenosis >50%) was 31% (37% in PTCA patients, 17% in stented patients). At all time periods, including baseline, uPA antigen levels were significantly higher and PAI-1 antigen levels were significantly lower in patients with restenosis. Restenosis rates for patients in the upper tertile of baseline uPA antigen levels were 2-fold higher than for those in the lower 2 tertiles (46% versus 24% and 22%, respectively; P<0.004). In a stepwise regression multivariate analysis, obstruction diameter after the procedure and uPA antigen were significant predictors of follow-up diameter stenosis. CONCLUSIONS Plasma uPA antigen levels and PAI-1 antigen levels identify patients at increased risk for restenosis after percutaneous coronary revascularization.
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Srinivasan R, Reddy RA, Rene S, Kanungo R, Natarajan MK. Bacterial contamination of anterior chamber during IOL surgery. Indian J Ophthalmol 1999; 47:185-9. [PMID: 10858775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
PURPOSE To study the nature and frequency of bacterial contamination during cataract surgery. METHODS The preoperative smears from the conjunctiva and anterior chamber (AC) fluid aspirates during extra-capsular cataract surgery (ECCE) with posterior chamber intraocular lens (PCIOL) implantation in 40 eyes were analysed for aerobic and anaerobic bacteria. Any change in the bacterial strains isolated before and after cataract surgery was also studied. RESULTS AC fluid aspirates were positive for bacteria in 15 eyes (37.5%). Coagulase-negative Staphylococcus was the most common aerobe (39.4%) and Propionibacterium acnes the most common anaerobe. Of the 15 cases with positive AC fluid cultures, 6 showed an organism in the AC aspirate different from the conjunctival smear. CONCLUSION Clinically there was no endophthalmitis in any of the eyes. Factors such as preoperative antibiotic use, the antibacterial properties of aqueous, or low inoculum size could explain this. The preoperative conjunctival smear may not be useful in predicting the AC fluid contamination or outcome of cataract surgery.
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Natarajan MK. Use of abciximab is beneficial in stenting and balloon angioplasty. EVIDENCE-BASED CARDIOVASCULAR MEDICINE 1998; 2:107. [PMID: 16379857 DOI: 10.1016/s1361-2611(98)80046-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
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