Amol Bahekar

Cardiovascular Outcomes Using Intra-Aortic Balloon Pump in High-Risk Acute Myocardial Infarction With or Without Cardiogenic Shock: A Meta-Analysis

Background: Intra-aortic balloon pump (IABP) has been widely used ever since it was first developed in 1962 and became part of clinical practice in 1968. It is used to treat patients with complications of acute myocardial infarction (AMI) such as cardiogenic shock, refractory left ventricular failure, and for high-risk patients undergoing angioplasty and coronary artery bypass grafting. However, current literature demonstrates a significant variance in terms of indications for using IABP and its outcomes. The aim of this study is to review the existing literature to analyze whether the use of IABP offers any cardiovascular benefit to the patients with AMI and the complications associated with the use of IABP. Material and Methods: A systematic review of literature identified 16 studies. We analyzed the primary endpoint (in-hospital mortality, reinfarction, recurrent ischemia) and secondary endpoint (incidence of moderate and severe bleeding during hospitalization at 7 days). We estimated the proportion of between-study inconsistency (heterogeneity) due to true differences between studies (rather than differences due to random error or chance) using the I2 statistic. Mantel-Haenszel fixed-effect model was used to calculate the combined relative risks (RRs) when studies were homogenous, and the random effect model was used when studies were heterogenic. A 2-sided α error <.05 was considered statistically significant. Results: Meta-analysis revealed that in-hospital mortality of patients with AMI with and without cardiogenic shock did not differ between IABP group as compared to no IABP group (RR: 1.11; confidence interval [CI]: 0.69-1.78; P = .67). However, analysis of patients with AMI with cardiogenic shock showed statistically significant improvement in mortality (RR: 0.72; CI: 0.60-0.86; P < .0004). There was no significant reduction in the rate of reinfarction (RR: 0.81; CI: 0.30-2.17; P = .67) or recurrent ischemia (RR: 0.78; CI: 0.34-1.78; P = .55) using IABP. Intra-aortic balloon pump was found to significantly increase the risk of moderate bleeding (RR: 1.71; CI: 1.03-2.85; P = .04) and major bleeding (RR: 4.01; CI: 2.66-6.06; P < .0001). Conclusion: The present meta-analysis suggests that patients with high-risk AMI without cardiogenic shock do not seem to benefit from the use of IABP as measured by in-hospital mortality, rate of reinfarction, and recurrent angina. However, in patients with AMI with cardiogenic shock (systolic blood pressure [SBP] < 90), there was significant reduction in mortality using IABP. The use of IABP is associated with increase in the rate of both moderate and severe bleeding.

Complete versus culprit only revascularization in acute ST elevation myocardial infarction: A meta‐analysis

Background: Current guidelines recommend against the revascularization of noninfarct related artery (complete revascularization [CR]) in patients with ST elevation myocardial infarction (STEMI) and no hemodynamic compromise, though level of evidence is C. Aim: Our aim was to examine the available evidence to determine any advantage of CR over culprit only revascularization (COR). Methods: We systematically searched medline using key words—“culprit coronary revascularization,” “complete revascularization myocardial infarction,” and “multivessel STEMI” for studies reporting outcomes after COR versus CR during primary procedure or index hospitalization published in English language and indexed before February 2010. A random effect or fixed effect meta‐analysis, as applicable, was performed using RevMan 5 (Cochrane Center, Denmark). Results: Nine eligible nonrandomized studies amounting to 4,530 patients in CR and 27,323 patients in COR group were included. In addition, two small randomized trials were reviewed and included in secondary analysis. Majority of patients were hemodynamically stable. Major adverse cardiovascular events (Odds ratio [OR] = 0.95, 95% CI 0.47–1.90) and long term mortality (OR = 1.10, 95% CI 0.76–1.59) were similar. The marginal increased odds of in‐hospital mortality was derived from a single study with no difference found after sensitivity and cumulative analysis (OR = 1.21 95% CI 0.85–1.73). Conclusion: Current analysis of heterogeneous studies did not reveal any benefit of CR over COR in patients with STEMI. However, also provide no conclusive evidence of increased in hospital mortality after CR. A randomized trial is needed to confirm these findings and recognize any subgroup which might benefit from CR.

Increased Incidence of In-Stent Thrombosis Related to Cocaine Use: Case Series and Review of Literature

The purpose of this article was to determine the incidence of in-stent thrombosis (IST) after coronary stent implantation in patients with cocaine abuse. A retrospective review was done of medical records of consecutive patients who underwent coronary stent implantation for obstructive coronary artery disease at a single inner-city institution from January 1997 to October 2006. Patients with temporal cocaine use were identified by positive urine drug screen. IST was confirmed angiographically. Of the 81 patients with active cocaine use that underwent coronary stent implantation, 4 (5%) suffered IST (mean period from stent implantation, 28.5 ± 14 days). All procedures were performed successfully and received intravenous IIb/IIIa antagonist intraprocedurally. All patients were prescribed dual antiplatelet therapy with aspirin and clopidogrel at discharge; however, all 4 patients that suffered from IST continued cocaine abuse were noncompliant with the prescribed dual antiplatelet therapy. Of these 4 patients, 2 presented with ST segment elevation myocardial infarction (50%), whereas 2 presented with non-ST-segment elevation myocardial infarction (50%). One was managed medically. Two received repeat percutaneous coronary intervention, and 1 underwent coronary artery bypass surgery. The patient that underwent surgery died in the postoperative period. The remaining 3 patients survived. Patients with active cocaine abuse who undergo successful coronary stent revascularization have a high (5%) incidence of stent thrombosis. A majority of patients that suffer stent thrombosis continue cocaine abuse and are noncompliant with antiplatelet therapy.

Glycoprotein IIb/IIIa inhibitors with or without thienopyridine pretreatment improve outcomes after primary percutaneous coronary intervention in high-risk patients with ST elevation myocardial infarction--a meta-regression of randomized controlled trials.

Recent studies have casted a doubt on usefulness of routine glycoprotein IIb/IIIA inhibitors (GPI) in patients, pretreated with aspirin and clopidogrel, undergoing primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI).

Prevention of Recurrent Atrial Fibrillation With Angiotensin-Converting Enzyme Inhibitors or Angiotensin Receptor Blockers: A Systematic Review and Meta-Analysis of Randomized Trials:

Background: Controversy persists regarding the efficacy of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) in the prevention of recurrent atrial fibrillation (AF). We performed a meta-analysis of randomized controlled trials (RCTs), not designed a priori to test this hypothesis, to explore whether ACEs and ARBs reduce recurrent AF. Methods: We performed a systematic literature search for RCTs using ACEIs or ARBs and providing data on the outcome of recurrent AF. Statistical heterogeneity across the trials was tested using the Cochran Q statistic and I2 was computed to quantify heterogeneity. A 2-sided α error of less than .05 was considered statistically significant (P < .05). Results: The analysis was based on 8 RCTs including 2323 patients. The Mantel-Haenszel random-effect model was used to calculate relative risk (RR) for studies using ACEIs or ARBs, and for studies using ARBs. The fixed-effect model was used to calculate RR for studies using ACEIs. Meta-analysis of the studies revealed that ACEIs or ARBs significantly reduced the incidence of recurrent AF (RR, 0.611; 95% CI, 0.441-0.847; P = .003). The RR for recurrent AF was 0.643 (95% CI, 0.439-0.941; P = .023) for studies using ARBs and 0.54 (95% CI, 0.377-0.80; P = .002) for studies using ACEIs. Conclusion: In this meta-analysis of RCTs not designed a priori to test the hypothesis, ACEs and ARBs were associated with a significant reduction in recurrent AF. Large-scale randomized trials designed a priori to test the hypothesis are necessary to complete the totality of evidence.

Tirofiban Use With Clopidogrel and Aspirin Decreases Adverse Cardiovascular Events After Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction: A Meta-analysis of Randomized Trials

Current guidelines deemed usefulness of routine early glycoprotein IIb/IIIa inhibitor (GPI) administration in ST-elevation myocardial infarction (STEMI) before primary percutaneous coronary intervention (PCI) with dual antiplatelet therapy as uncertain. We aimed to examine the current evidence for the use of tirofiban, a nonpeptide glycoprotein IIb/IIIa inhibitor, in STEMI patients treated with dual antiplatelet therapy. We performed systematic searches of MEDLINE, EMBASE, and CENTRAL databases for randomized controlled trials (RCTs) of tirofiban use in STEMI patients treated with aspirin and clopidogrel which reported clinical and/or angiographic outcomes after primary PCI. Data were combined using random effect and fixed effect models for heterogeneous and homogeneous outcomes respectively using Review Manager 5 (The Nordic Cochrane Centre, The Cochrane Collaboration, 2008). Six randomized controlled trials were eligible for the inclusion; involving 708 patients in tirofiban group and 721 control subjects. Routine tirofiban use decreased the major adverse cardiovascular events (odds ratio [OR] 0.50; 95% confidence interval [CI], 0.26-0.94). Corrected thrombolysis in myocardial infarction (TIMI) frame count was also reduced with tirofiban (mean difference -8.48 [95% CI, -12.62 to -4.34]). There were no significant differences in the rates of postprocedure TIMI flow grade 3 and TIMI myocardial perfusion/blush grade 3, major bleeding by TIMI criteria, or mortality in the 2 groups. Current analysis of available studies suggests that routine and early tirofiban use before primary PCI may decrease the major cardiovascular events in STEMI patients treated with aspirin and clopidogrel without any significant increase in major bleeding. An adequately powered randomized trial is urgently needed to confirm the above findings and estimate the effect size.

Adjunctive Low Molecular Weight Heparin During Fibrinolytic Therapy in Acute ST‐Segment Elevation Myocardial Infarction: A Meta‐Analysis Of Randomized Control Trials

Recent data suggests that low molecular weight heparins (LMWHs) may be superior to unfractionated heparin (UFH) as an adjunct to fibrinolytic therapy in patients with acute ST‐segment elevation myocardial infarction (STEMI).

Is Appropriate Use Criteria for Cardiac Radionuclide Imaging in Asymptomatic Diabetic Patients Evidence Based

We write in reference to the recent article in the Journal , the 2009 Appropriate Use Criteria for Cardiac Radionuclide Imaging (RNI), which was published by the American College of Cardiology and endorsed by many other professional societies ([1][1]). This document was anticipated to impact

DIAGNOSTIC ACCURACY OF HIGH SENSITIVITY TROPONIN: A META-ANALYSIS

Recently, high sensitive troponin (HsTrop) assays consistent with professional societies’ recommendations, with a level of detection and 10% coefficient of variation (CV) below 99 percentile of the normal population became available. We aimed to summarize the available evidence on diagnostic

Rebuttal: Culprit only versus complete revascularization in st elevation myocardial infarction

We read the letter to the editor regarding our metaanalysis with great interest. It is an articulate representation of prevailing concerns in cardiology community regarding complete revascularization in patients with ST elevation myocardial infarction (STEMI). The writer correctly points out the variability in definitions used across the studies to describe the complete revascularization procedure. In particular, studies have defined the complete revascularization to encompass the revascularization of nonculprit vessels performed during the index procedure, index hospitalization or as staged procedure postindex hospitalization [1,2]. To deal with this ambiguity, we restricted our meta-analysis to studies, which performed complete revascularization during index hospitalization. The writer has raised several other important issues.