<?xml version="1.0" encoding="utf-8"?>
<recommendedContent xmlns="http://api.mspoke.com">
    <recommendedItem id="20100101_19_458"
                     title="Calcium Scoring Misses 20% of CAD Cases (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/Cardiology/AcuteCoronarySyndrome/tb/18387?impressionId=1265758524584"
                     
      &lt;p&gt;Contrary to guidelines, the absence of coronary artery calcium doesn&apos;t rule out coronary artery disease in symptomatic patients, researchers found in a new study.&lt;/p&gt;
&lt;p&gt;In a multicenter clinical trial, 19% of patients with a coronary calcium score of 0 had stenosis of at least 50% in one or more coronary artery segments, according to Carlos E. Rochitte, MD, of the University of S&amp;#227;o Paulo, Brazil, and colleagues.&lt;/p&gt;
&lt;p&gt;Likewise, 20% of vessels seen to be totally occluded on revascularization had no calcium on scans, they reported in the Feb. 16 issue of the &lt;em&gt; Journal of the American College of Cardiology&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;&quot;The absence of coronary calcification should not be used as a gatekeeper and should not prevent a symptomatic patient from undergoing angiography,&quot; the researchers wrote.&lt;/p&gt;
&lt;p&gt;Currently, American Heart Association/American College of Cardiology guidelines suggest that excluding measurable coronary calcium could serve as an effective filter for sending patients on to invasive testing or admitting them.&lt;/p&gt;
&lt;p&gt;One systematic review of 18 studies had indicated that a zero calcium score had a negative predictive value of 93% for stenosis and a positive predictive value of 68% in symptomatic patients.&lt;/p&gt;
&lt;p&gt;However, in Rochitte&apos;s trial  --  CORE64 (Coronary Evaluation Using Multi-Detector Spiral Computed Tomography Angiography Using 64 Detectors)  --  the negative predictive value of a coronary calcium score of 0 was 68%, while the positive predictive value was 81%.&lt;/p&gt;
&lt;p&gt;Overall sensitivity to predict the absence of significant (at least 50%) stenosis was 45%, while specificity was 91%.&lt;/p&gt;
&lt;p&gt;&quot;This apparent lack of predictive value of a calcium scan should be enough to give a clinician pause,&quot; Rita F. Redberg, MD, of the University of California San Francisco, wrote in an accompanying editorial.&lt;/p&gt;
&lt;p&gt;Whatever the reason for the discrepancy, neither the trial nor the review provided any information on how coronary calcium scans add incrementally to traditional predictors of coronary artery disease, such as clinical assessment and stress testing, she said. Nor would she rule out their use entirely for patients with chest pain.&lt;/p&gt;
&lt;p&gt;&quot;Given the significant &lt;a href=&quot;http://www.medpagetoday.com/Cardiology/AcuteCoronarySyndrome/12732&quot; mce_href=&quot;http://www.medpagetoday.com/Cardiology/AcuteCoronarySyndrome/12732&quot; target=&quot;_blank&quot;&gt;radiation risks&lt;/a&gt; of coronary artery calcium scans, however, clinicians must use extreme caution when ordering such scans,&quot; Redberg cautioned.&lt;/p&gt;
&lt;p&gt;The prospective &lt;a href=&quot;http://www.medpagetoday.com/Radiology/DiagnosticRadiology/11927&quot; mce_href=&quot;http://www.medpagetoday.com/Radiology/DiagnosticRadiology/11927&quot; target=&quot;_blank&quot;&gt;CORE64 study&lt;/a&gt; was originally designed to compare diagnostic performance of CT and invasive angiography in symptomatic patients with suspected coronary artery disease. But it also included a coronary calcium scan up to 30 days prior to conventional angiography.&lt;/p&gt;
&lt;p&gt;Of the 291 patients included in the calcium score analysis (73% male, mean age 59.3), 56% had at least 50% coronary stenosis by conventional angiography and 45% had at least 70% stenosis.&lt;/p&gt;
&lt;p&gt;Calcium score only weakly correlated with the highest degree of coronary stenosis found in a patient. Its ability to predict presence of significant lesions was &quot;moderate&quot; (area under the receiver-operating characteristic curve 0.77, &lt;em&gt;P&lt;/em&gt;&amp;lt;0.001).&lt;/p&gt;
&lt;p&gt;A non-zero score was associated with 8.1-fold likelihood of having at least 50% coronary stenosis (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.001) after adjusting for age, sex, hypertension, dyslipidemia, family history of premature heart disease, diabetes, race, and hospitalization.&lt;/p&gt;
&lt;p&gt;Among the 100 patients who went on to revascularization within 30 days of angiography, 13% had a coronary calcium score of 0, 25% had a score of 1 to 10, and 44% had a score over 10 (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.001 for trend).&lt;/p&gt;
&lt;p&gt;The fact that significant coronary artery disease occurred in the absence of calcification in almost 20% of patients should not be surprising, since coronary calcification is thought to occur late in the atherosclerotic process, while obstruction can occur earlier, Redberg asserted.&lt;/p&gt;
&lt;p&gt;The researchers also cautioned that the results would not apply to asymptomatic patients with intermediate risk for events, a group in which a score of 0 has been consistently shown to indicate low risk.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was supported by grants from Toshiba Medical Systems, the Doris Duke Charitable Foundation, the National Heart, Lung, and Blood Institute, the National Institute on Aging, and the Donald W. Reynolds Foundation.&lt;/p&gt;&lt;p&gt;Rochitte reported no conflicts of interest. Co-authors reported financial relationships with Toshiba Medical Systems, Bayer, Schering, GE Healthcare, Bracco, Bristol-Myers Squibb, sanofi-aventis, and Vital Images.&lt;/p&gt;&lt;p&gt;Redberg provided no information on conflicts of interest.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_457"
                     title="Long-Term Safety of Drug-Eluting Stents Affirmed (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/Cardiology/Atherosclerosis/tb/18374?impressionId=1265758524584"
                     
      &lt;p&gt;Using sirolimus-eluting stents for the treatment of in-stent restenosis appears safe and effective over four years of follow-up, a study of an Italian registry showed.&lt;/p&gt;
&lt;p&gt;Through four years, there were low rates of target lesion revascularization (11.1%) and stent thrombosis (2.8%), according to Francesco Liistro, MD, of San Donato Hospital in Arezzo, Italy, and colleagues.&lt;/p&gt;
&lt;p&gt;About one in 10 patients (9.8%) died, and 3.2% had a nonfatal myocardial infarction.&lt;/p&gt;
&lt;p&gt;Survival free from a major adverse cardiac event was 80.3% at the end of follow-up, the researchers reported in the Feb. 16 issue of the&lt;em&gt; Journal of the American College of Cardiology&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;Although drug-eluting stents have been shown to be safe and better than balloon angioplasty and vascular brachytherapy for in-stent restenosis in the short term, most previous studies have had limited follow-up.&lt;/p&gt;
&lt;p&gt;Reports of late stent thrombosis following implantation with drug-eluting stents have raised some concern about the long-term safety of these devices in unselected patient groups, according to Liistro and his colleagues.&lt;/p&gt;
&lt;p&gt;To explore the issue, the researchers turned to the Tuscany Registry of Unselected In-Stent Restenosis (TRUE), a prospective, two-center registry.&lt;/p&gt;
&lt;p&gt;All 244 patients included in the analysis underwent antiplatelet therapy with aspirin and either ticlopidine or clopidogrel (Plavix) for at least six months after the sirolimus-eluting stent was implanted.&lt;/p&gt;
&lt;p&gt;An earlier, nine-month analysis of this registry showed safety and effectiveness for the stent. This study confirmed the benefits through four years.&lt;/p&gt;
&lt;p&gt;Of 24 recorded deaths, 11 were from cardiac causes.&lt;/p&gt;
&lt;p&gt;Definite stent thrombosis occurred in five patients, four of whom had stopped taking clopidogrel more than a month before the event.&lt;/p&gt;
&lt;p&gt;Another two patients who were taking aspirin and clopidogrel had probable stent thrombosis.&lt;/p&gt;
&lt;p&gt;Patients who had diabetes were significantly more likely to have target lesion revascularization (OR 0.32, 95% CI 0.14 to 0.71) and major adverse cardiac events (OR 0.38, 95% CI 0.20 to 0.71) through four years.&lt;/p&gt;
&lt;p&gt;A left ventricular ejection fraction less than 50% was associated with higher odds of major adverse cardiac events (OR 0.32, 95% CI 0.13 to 0.80), as was creatinine greater than 1.5 mg/dL (OR 0.23, 95% CI 0.11 to 0.48).&lt;/p&gt;
&lt;p&gt;And patients with peripheral or carotid arterial disease were more likely to need target lesion revascularization (OR 0.35, 95% CI 0.14 to 0.88).&lt;/p&gt;
&lt;p&gt;The authors noted that the registry study was limited by the lack of valid control groups.&lt;/p&gt;
&lt;p&gt;In addition, in patients with a late occurrence of target lesion revascularization, the researchers could not determine whether a stenotic lesion inside the stented segment was a new atherosclerotic lesion or a restenosis.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The authors did not make any financial disclosures.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_348"
                     title="No Rebound Seen After Antiplatelet Withdrawal (CME/CE)"
                     score="0.008"
                     href="http://www.medpagetoday.com/Cardiology/PCI/tb/18226?impressionId=1265758524584"
                     
      &lt;p&gt;No evidence of a platelet aggregation rebound occurs with abrupt discontinuation of clopidogrel (Plavix) in patients undergoing percutaneous coronary intervention (PCI), investigators in a randomized clinical trial concluded.&lt;/p&gt;
&lt;p&gt;Values for adenosine diphosphate (ADP)-induced platelet aggregation did not differ significantly between patients whose clopidogrel therapy was withdrawn abruptly and those in whom clopidogrel was tapered before discontinuation, they wrote in an article in the Feb. 9 issue of the &lt;em&gt;Journal of the American College of Cardiology&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;The findings also showed that tapering of clopidogrel does not lead to lower platelet aggregation values after clopidogrel withdrawal, according to Dirk Sibbing, MD, of Technical University Munich in Germany, and colleagues&lt;em&gt;&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;&quot;The time course of platelet aggregation values  --  regardless of the device, the agonist, or the agonist concentration used  --  after clopidogrel cessation provides no evidence for the existence of a rebound phenomenon of platelets after discontinuing clopidogrel,&quot; they wrote in conclusion.&lt;/p&gt;
&lt;p&gt;For patients undergoing PCI, dual antiplatelet therapy with aspirin and clopidogrel has become the mainstay for prevention of thrombotic events. Lifelong aspirin therapy is recommended for patients after PCI, but clinical guidelines recommend discontinuation of clopidogrel after six or 12 months. The standard practice is to withdraw clopidogrel abruptly, the authors noted.&lt;/p&gt;
&lt;p&gt;Recent studies have shown a clustering of thrombotic events in the first few weeks after discontinuation of long-term clopidogrel therapy. The observations have led to the hypothesis of a rebound phenomenon of platelet aggregation. However, the hypothesis had not been examined specifically within the context of clopidogrel withdrawal.&lt;/p&gt;
&lt;p&gt;&quot;Because different studies have demonstrated that insufficient suppression of platelet reactivity to ADP is associated with an increased risk of thrombotic events after coronary stent placement, the observed clustering of adverse events reported in clinical studies might be related to an intermittent status of platelet hyperreactivity or so-called platelet rebound with very high ADP-induced platelet aggregation levels,&quot; the authors wrote.&lt;/p&gt;
&lt;p&gt;&quot;A tapering of clopidogrel treatment over a certain period of time before stopping the intake of the drug completely might provide a beneficial treatment strategy to attenuate this supposed rebound phenomenon of platelets.&quot;&lt;/p&gt;
&lt;p&gt;Sibbing and colleagues designed a randomized clinical trial to determine whether a rebound phenomenon exists after discontinuation of clopidogrel and whether the rebound can be attenuated by a clopidogrel-tapering regimen.&lt;/p&gt;
&lt;p&gt;The investigators enrolled 69 patients receiving clopidogrel in association with PCI procedures. In all cases, discontinuation of clopidogrel was planned.&lt;/p&gt;
&lt;p&gt;The patients were randomized to two strategies of discontinuation: tapering of the clopidogrel dose over four weeks, followed by discontinuation; or treatment for four weeks, as planned, followed by abrupt discontinuation.&lt;/p&gt;
&lt;p&gt;Investigators assessed platelet aggregation at enrollment and during weeks two through eight after randomization. Aggregation was assessed simultaneously by light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA).&lt;/p&gt;
&lt;p&gt;The primary endpoint was the highest rate of ADP-induced platelet aggregation by LTA in weeks five through eight after clopidogrel withdrawal.&lt;/p&gt;
&lt;p&gt;Platelet aggregation by LTA peaked at 73% in the group that had clopidogrel abruptly withdrawn and at 69.3% in the tapering group, resulting in a nonsignificant difference (&lt;em&gt;P&lt;/em&gt;=0.21). The between-group values did not differ across the range of ADP concentrations used (1.25 to 20 &amp;#181;mol/L).&lt;/p&gt;
&lt;p&gt;Results by MEA were similar: The peak aggregation value associated with abrupt withdrawal was 925 AU x min compared with 890 AU x min with clopidogrel tapering (&lt;em&gt;P&lt;/em&gt;=0.55).&lt;/p&gt;
&lt;p&gt;Studies with different agonists of platelet aggregation also yielded similar results in the two patient groups.&lt;/p&gt;
&lt;p&gt;Despite finding no difference between the two strategies for clopidogrel withdrawal, the authors did not rule out the possibility of a beneficial effect of tapering clopidogrel.&lt;/p&gt;
&lt;p&gt;&quot;It could be hypothesized that, apart from the maximal values of platelet aggregation observed, a more gradual increase of platelet aggregation values achieved by a clopidogrel-tapering regimen is beneficial for the reduction of thrombotic events,&quot; the authors wrote.&lt;/p&gt;
&lt;p&gt;&quot;In fact, we observed a relatively rapid increase of platelet aggregation values in the [abrupt withdrawal] group of patients in our study. Whether this rapid increase might be disadvantageous in case of stopping clopidogrel treatment remains uncertain.&quot;&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was supported by Cordis, Medtronic, and Dynabyte.&lt;/p&gt;&lt;p&gt;Sibbing disclosed relationships with Dynabyte and Eli Lilly.&lt;/p&gt;&lt;p&gt;Co-author Adnan Kastrati disclosed relationships with Eli Lilly, sanofi-aventis, and Bristol-Myers Squibb.&lt;/p&gt;&lt;p&gt;Co-author Nicolas von Beckerath disclosed relationships with Eli Lilly and sanofi-aventis.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_316"
                     title="STS: Delay in Treating Blunt Aortic Trauma Works Best (CME/CE)"
                     score="0.006"
                     href="http://www.medpagetoday.com/MeetingCoverage/STS/tb/18180?impressionId=1265758524584"
                     
      &lt;p&gt;FORT LAUDERDALE  --  Researchers here suggest that delaying treatment of selected blunt thoracic aortic injuries appears to improve overall survival of these critically ill patients.&lt;/p&gt;
&lt;p&gt;&quot;Although thoracic aortic injury still accounts for significant mortality during blunt trauma, patients reaching specialized trauma centers can achieve good results with thoracic aortic repair,&quot; said Anthony L. Estrera, MD, of the University of Texas Houston Medical School.&lt;/p&gt;
&lt;p&gt;In fact, since 1997, improved treatments have produced a 5.9% annual reduction in operative mortality and a 3% annual reduction among patients with blunt thoracic aorta injuries, he told colleagues at the annual meeting of the Society of Thoracic Surgeons here.&lt;/p&gt;
&lt;p&gt;Estrera reviewed the evolution of treatment, noting that between 1988 and 1996, his institution&apos;s doctors brought 75 patients to the operating room, 71 of whom had open surgery.&lt;/p&gt;
&lt;p&gt;Since then, treatment has changed with methods that include distal perfusion, the concept of treatment delay, and the development of thoracic endovascular aortic repair (TEVAR) using stent devices.&lt;/p&gt;
&lt;p&gt;At the Houston Level I trauma center, doctors treated 60,091 patients between January 1997 and March 2009, including 250 who were admitted with blunt thoracic aortic injury.&lt;/p&gt;
&lt;p&gt;Estrera said the average age of the patients was 32, and 70% were men. About three-fourths of the patients were riding in vehicles involved in accidents. Other victims included pedestrians and bicyclists, people who suffered falls, and one who was injured in a parachuting accident.&lt;/p&gt;
&lt;p&gt;About 35% died at or near time of admission; the others were ultimately repaired, Estrera reported.&lt;/p&gt;
&lt;p&gt;&quot;The overall mortality for the diagnosis of acute thoracic aorta injury was 44%,&quot; he said, including those who did not receive repair. &quot;Of those who underwent operative repair, mortality was 17%.&quot;&lt;/p&gt;
&lt;p&gt;Some 41% of the patients had delayed repair, which was associated with only one death, Estrata added. There was 28% mortality among those patients who underwent early surgery.&lt;/p&gt;
&lt;p&gt;He said 90 percent of the TEVAR cases involved delayed surgery  --  a median of four days from admission to the operating room.&lt;/p&gt;
&lt;p&gt;When researchers attempted to tease out what might be significant factors in reducing mortality, delayed repair &quot;was the only factor that was protective against mortality in this series,&quot; he said.&lt;/p&gt;
&lt;p&gt;Other surgeons agreed that delayed surgery is far more common now.&lt;/p&gt;
&lt;p&gt;&quot;It used to be that any time there was an indication of thoracic aorta disturbance, the patients was rushed to surgery and they underwent this massive surgery where you had to heparinize them,&quot; said Matthew Williams, MD, assistant professor of surgery at the University of Louisville.&lt;/p&gt;
&lt;p&gt;&quot;Since then, this idea of surgical delay has come forth. We let the patient&apos;s injuries calm down and take care of the other injuries and then do the thoracic aorta repair on sort of an elective basis.&lt;/p&gt;
&lt;p&gt;&quot;The combination of this idea and TEVAR has created the major chance in the management of blunt aortic thoracic injury. There is good data now to support this strategy, but if you have a patient that dies while you are waiting, there might be a problem with litigation. That may make some people a little bit reticent.&quot;&lt;/p&gt;
&lt;p&gt;Estrera said surgeons still have some concerns about TEVAR itself. &quot;The problem with TEVAR is the unknown factor of what is the durability of the TEVAR device especially in the younger patients,&quot; he said.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;Estrera and Williams did not have any relevant disclosures.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_284"
                     title="STS: Leg Artery Access Linked to Dissection (CME/CE)"
                     score="0.004"
                     href="http://www.medpagetoday.com/MeetingCoverage/STS/tb/18139?impressionId=1265758524584"
                     
      &lt;p&gt;FORT LAUDERDALE  --  Avoiding femoral artery cannulization during cardiac surgery might eliminate some of the rare but potentially catastrophic aortic dissections that occur during the procedure, researchers said here.&lt;/p&gt;
&lt;p&gt;Doctors identified the femoral location as an increased risk factor in an analysis of records from the Society of Thoracic Surgeons&apos; national database of more than 2.2 million cardiac surgeries. That search yielded 1,294 incidents of aortic dissection.&lt;/p&gt;
&lt;p&gt;&quot;Prevention is the key,&quot; Matthew Williams, MD, of the University of Louisville, said at the annual meeting of the Society of Thoracic Surgeons here.&lt;/p&gt;
&lt;p&gt;Williams and colleagues reported that aortic dissection occurs in only 0.06% of cardiac surgeries but accounts for almost one percent of perioperative deaths.&lt;/p&gt;
&lt;p&gt;&quot;Aortic dissection is a low frequency but catastrophic event,&quot; Williams said, noting that 48% of aortic dissections during surgery prove fatal. Some 9% of the survivors suffer strokes and 14% experience kidney failure.&lt;/p&gt;
&lt;p&gt;He recalled becoming interested in the research after one of his patients, a woman, experienced aortic dissection during a procedure. &quot;She walked out of the hospital,&quot; he said.&lt;/p&gt;
&lt;p&gt;He told &lt;em&gt;MedPage Today&lt;/em&gt; that &quot;the incidence of these aortic dissections is so small that only a large database project such as this one could possibly get at these cases.&quot;&lt;/p&gt;
&lt;p&gt;According to his presentation materials, researchers created a logistic regression model based on 2004-2007 STS data. The analysis turned up nine significant risk factors, including femoral cannulization, preoperative steroids, and Asian race. Diabetes appeared to be protective.&lt;/p&gt;
&lt;p&gt;When aortic dissection occurs during surgery, Williams said, doctors generally stop the operation and attempt to restart it by cannulization in another area.&lt;/p&gt;
&lt;p&gt;He said he has considered femoral access as a last resort and prefers either central aortic cannulization or axial cannulization.&lt;/p&gt;
&lt;p&gt;He said improving outcomes and identifying what causes aortic dissection in these surgical cases may require changes and updates in the information captured by the database. He said a clinical trial would require so many patients that it would not be practical.&lt;/p&gt;
&lt;p&gt;Aubrey Galloway, MD, of the New York University School of Medicine, who was the discussant for Williams&apos; talk, said that the imprecise nature of the way the data are gathered might have misidentified the femoral access point as a culprit procedure.&lt;/p&gt;
&lt;p&gt;&quot;It may be that femoral access was employed in response to another dissection site,&quot; he said.&lt;/p&gt;
&lt;p&gt;Williams responded that by tweaking the information acquired by the database it might be possible to better determine these associations.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;Williams listed no relevant disclosures; Galloway disclosed financial relationships with Medtronic and Edwards Life Sciences and Estech.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
</recommendedContent>