<?xml version="1.0" encoding="utf-8"?>
<recommendedContent xmlns="http://api.mspoke.com">
    <recommendedItem id="20100101_19_441"
                     title="Be Ready for Drug-Induced Vfib, Groups Urge (CME/CE)"
                     score="0.014"
                     href="http://www.medpagetoday.com/Cardiology/Arrhythmias/tb/18358?impressionId=1265745575779"
                     
      Awareness of medication-induced torsade de pointes and a preset protocol for treating it could save lives in the hospital with swift action to prevent cardiac arrest, according to a joint statement from two professional associations.&lt;br&gt;
&lt;br&gt;These cases &quot;should be avoidable&quot; with consistent electrocardiographic monitoring of patients receiving drugs known to prolong the QT interval, the American Heart Association and American College of Cardiology wrote in a statement endorsed by the American Association of Critical-Care Nurses.&lt;br&gt;
&lt;br&gt;The rare arrhythmia often provides telltale signs on ECG an hour or so before ventricular fibrillation, according to writing committee chair Barbara J. Drew, RN, PhD, of the University of California San Francisco, and colleagues.&lt;/p&gt;
&lt;p&gt;However, the statement made no one-size-fits-all recommendation on what cardiac monitoring should entail, given hospital-to-hospital differences in equipment that range from fully automated QT-monitoring systems at the high end to a computer-assisted electronic caliper feature at the other.&lt;/p&gt;
&lt;p&gt;&quot;Of utmost importance, however, is that a hospital protocol be established so that a single consistent method is used by all healthcare professionals charged with the responsibility for cardiac monitoring,&quot; Drew&apos;s group wrote.&lt;/p&gt;
&lt;p&gt;This protocol should stipulate which equipment to use for QT measurement, how to determine the end of the T wave, the formula for heart rate correction, lead-selection criteria, and the importance of measuring the same lead in the same patient over time, they said.&lt;/p&gt;
&lt;p&gt;The new statement, published online in &lt;em&gt;Circulation: Journal of the American Heart Association&lt;/em&gt; and the &lt;em&gt;Journal of the American College of Cardiology&lt;/em&gt;, included the following signs of impending torsade de pointes: &lt;ul&gt; &lt;li&gt;An increase of 60 ms in heart-rate&amp;#8211;corrected QT interval (QTc) from the preadministration baseline&lt;/li&gt; &lt;li&gt;Marked QTc interval prolongation of more than 500 ms&lt;/li&gt; &lt;li&gt;The characteristic &quot;twisting&quot; of the points on ECG as T-U wave distortion becomes more exaggerated in the beat after a pause&lt;/li&gt; &lt;li&gt;Visible (macroscopic) T-wave alternans&lt;/li&gt; &lt;li&gt;New-onset ventricular ectopy&lt;/li&gt; &lt;li&gt;Couplets and &lt;span&gt;nonsustained&lt;/span&gt; polymorphic ventricular tachycardia initiated in the beat after a pause&lt;/li&gt; &lt;/ul&gt;&lt;/p&gt;
&lt;p&gt;Prompt recognition of these ECG harbingers allows for treatment with intravenous magnesium, removal of the drug that induced the condition, and correction of electrolyte abnormalities and other exacerbating factors, including the prevention of bradycardia and long pauses with temporary pacing if necessary, according to the new statement.&lt;/p&gt;
&lt;p&gt;Prior guidelines on ventricular arrhythmias provided little help with prevention of torsade de pointes in the hospital but did recommend discontinuation of whatever drug induced long QT syndrome.&lt;/p&gt;
&lt;p&gt;The most common drugs associated with this potentially fatal arrhythmia are antibiotics, antipsychotics, and antiarrhythmia drugs.&lt;/p&gt;
&lt;p&gt;Administration in the hospital is more likely to be associated with torsade de pointes than is treatment of an outpatient population with the same drug, Drew&apos;s group noted.&lt;/p&gt;
&lt;p&gt;Hospitalized patients are often elderly, with comorbidities such as underlying heart disease and renal or hepatic dysfunction. They are also more likely to get intravenous push of the drugs.&lt;/p&gt;
&lt;p&gt;Clinical risk factors for torsade de pointes include: &lt;ul&gt; &lt;li&gt;A preexisting long QTc interval of more than 500 ms&lt;/li&gt; &lt;li&gt;Concurrent use of more than one QT-prolonging drug&lt;/li&gt; &lt;li&gt;Rapid infusion of a QT-prolonging drug intravenously&lt;/li&gt; &lt;li&gt;Heart disease, such as MI or heart failure&lt;/li&gt; &lt;li&gt;Advanced age&lt;/li&gt; &lt;li&gt;Female sex&lt;/li&gt; &lt;li&gt;Hypokalemia&lt;/li&gt; &lt;li&gt;Hypomagnesemia&lt;/li&gt; &lt;li&gt;Hypocalcemia&lt;/li&gt; &lt;li&gt;Treatment with diuretics&lt;/li&gt; &lt;li&gt;Impaired hepatic drug metabolism, whether from hepatic dysfunction or drug-drug interactions&lt;/li&gt; &lt;li&gt;Bradycardia&lt;/li&gt; &lt;/ul&gt;&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;Drew reported conflicts of interest with GE Healthcare and Philips.&lt;/p&gt;&lt;p&gt;Co-authors reported conflicts of interest with Medtronic, Pfizer, PGxHealth, FAMILION, GE HealthCare, Philips Healthcare, Abbott, Bristol-Myers Squibb, sanofi-aventis, Schering Plough, Inovise, Siloam, ArgiNOx, Astellas, Daiichi Sankyo/Lilly, Heartscape Technologies, Biosite, Inovise, Medicines Co., Millennium Pharmaceuticals, PDL BioPharma, Roche Diagnostics, Scios, Mortara Instrument, Cardiac Science, MDS Pharma, Medicure, St. Jude, Adolor, ARCA, AstraZeneca, Avanir, Cardiome, CardioDx, Novartis, Ortho Diagnostics, Sanofi, Vanderbilt/Clinical Data, iCardiac Technologies, LipoScience, Anthera, Abbott Vascular, Novo Nordisk, Roche, Biotronic, and Boston Scientific.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_388"
                     title="Laser Cardiac Lead Extraction Gets Better Grades (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/Cardiology/Arrhythmias/tb/18280?impressionId=1265745575779"
                     
      &lt;p&gt;Laser-assisted extraction of implanted heart device leads appears to have become safer and more successful in recent years, researchers said.&lt;/p&gt;
&lt;p&gt;A retrospective multicenter series suggested a 97.7% clinical success rate and complete lead removal in 96.5% of cases attempted with the newer iteration of transvenous excimer laser extraction tools.&lt;/p&gt;
&lt;p&gt;Major procedural complication rates were low at 1.4% with 0.28% procedure-related deaths, Oussama M. Wazni, of the Cleveland Clinic, and colleagues reported 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;&quot;Since the initially reported experiences, which employed earlier editions of the extraction tools and largely represented the learning curve with laser extraction techniques, this consecutive patient experience represents the mature contemporary practice in multiple centers with varying degrees of experience,&quot; the researchers wrote.&lt;/p&gt;
&lt;p&gt;These results suggested improvements, they said, compared with the original PLEXES trial using the first version of a laser sheath for lead extraction, which showed 94% procedural success and 1.96% procedure-related major complications.&lt;/p&gt;
&lt;p&gt;Another study of the total initial U.S. experience of laser lead extraction indicated 90% procedural success with a 1.9% major complication rate and an inhospital death rate of 0.8%.&lt;/p&gt;
&lt;p&gt;The early, relatively small trials and voluntary registry results upon which the perceptions of lead extraction safety and effectiveness were based had painted a &lt;a href=&quot;http://www.medpagetoday.com/Cardiology/Arrhythmias/3162&quot; mce_href=&quot;http://www.medpagetoday.com/Cardiology/Arrhythmias/3162&quot; target=&quot;_blank&quot;&gt;picture&lt;/a&gt; that limited it to patients with life-threatening situations, Wazni&apos;s group explained.&lt;/p&gt;
&lt;p&gt;It used to be felt that removing infected leads was dangerous because of the potential for infected debris to spread through the bloodstream and become lodged in the lungs, commented Ann Bolger, MD, of San Francisco General Hospital and a spokesperson for the American Heart Association.&lt;/p&gt;
&lt;p&gt;&quot;Because there are just more and more patients all the time with these devices and because we went through a phase when we might not have always retrieved wires that were no longer functional completely, there are patients who have what they call abandoned leads,&quot; she said in an interview.&lt;/p&gt;
&lt;p&gt;AHA guidelines released last month now recommend removal of all hardware even in the absence of symptoms for patients with more than a superficial or incisional infection at the pocket site, suggesting percutaneous extraction as the preferred method despite significant risks.&lt;/p&gt;
&lt;p&gt;The AHA agreed with guidelines from the Heart Rhythm Society released last spring cautioning that only experienced centers should do extractions. The HRS went so far as to set &lt;a href=&quot;http://www.medpagetoday.com/MeetingCoverage/HRS/14255&quot; mce_href=&quot;http://www.medpagetoday.com/MeetingCoverage/HRS/14255&quot; target=&quot;_blank&quot;&gt;minimum standards&lt;/a&gt; for operators.&lt;/p&gt;
&lt;p&gt;For a look at more contemporary data, Wazni&apos;s group examined outcomes for 1,449 consecutive patients treated with transvenous laser-assisted lead extraction at 13 U.S. and Canadian centers between January 2004 and December 2007.&lt;/p&gt;
&lt;p&gt;Among the 2,405 procedures, 70% were for pacemakers leads and 29.2% for defibrillator leads, with most being active fixation leads (1,226).&lt;/p&gt;
&lt;p&gt;The extracted leads had been in place for an average of 82.1 months (range 0.4 to 356.8). They were taken out predominantly because of infection (29.2% device-related endocarditis and 27.7% pocket infection).&lt;/p&gt;
&lt;p&gt;More than a quarter were nonfunctional (26.6%), while an additional 11.1% were functional but abandoned.&lt;/p&gt;
&lt;p&gt;Removal was complete for 96.5% of the leads and partial for 2.3%. Clinical success  --  achieving the clinical goals associated with the indication for lead removal  --  was achieved in 97.7% of the cases.&lt;/p&gt;
&lt;p&gt;Clinical failure of the procedure was associated with low patient body mass index (less than 25 kg/m&lt;sup&gt;2&lt;/sup&gt;) and with a lower volume of procedures (60 or fewer) at a center over the four years (&lt;em&gt;P&lt;/em&gt;=0.0128).&lt;/p&gt;
&lt;p&gt;Procedural adverse events, too, were more common for low BMI patients (&lt;em&gt;P&lt;/em&gt;=0.0132).&lt;/p&gt;
&lt;p&gt;Procedural failure was linked to a long implant duration (at least 10 years) and lower center volume (&lt;em&gt;P&lt;/em&gt;=0.0005).&lt;/p&gt;
&lt;p&gt;Although extraction of noninfected but nonfunctional leads is controversial, leaving them in place may just serve as a nidus for infection such that they have to be removed eventually anyway, the researchers suggested.&lt;/p&gt;
&lt;p&gt;Considering extraction in such cases requires carefully weighing patient risks individually, including operator experience in the equation, they wrote.&lt;/p&gt;
&lt;p&gt;A significant learning curve for laser-assisted extraction is not surprising, but the results in experienced hands are encouraging, Bolger concluded.&lt;/p&gt;
&lt;p&gt;By the end of the study, physicians averaged 11.4 years of experience with lead extraction (range 2.0 to 19.0 years) and 7.87 years at laser-assisted lead extraction (range 2.0 to 13.0 years).&lt;/p&gt;
&lt;p&gt;The researchers agreed that the high success and low complication rate may have been due to the experienced centers and operators.&lt;/p&gt;
&lt;p&gt;&quot;However, in the community, these more challenging cases are usually referred to centers experienced in laser-assisted lead extraction,&quot; they wrote.&lt;/p&gt;
&lt;p&gt;They noted that any selection bias in the retrospective study was most likely toward the most challenging cases &quot;as laser-assisted extraction is reserved for leads with ingrown tissue and inability to be removed with traction only.&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 sponsored by Spectranetics, manufacturer of the laser lead removal system.&lt;/p&gt;&lt;p&gt;Wilkoff reported being on the advisory board of Spectranetics.&lt;/p&gt;&lt;p&gt;Co-authors reported financial conflicts of interests with Spectranetics, St. Jude, Medtronic, Boston Scientific, and Biotronik. One is an employee of Spectranetics; another is the senior biostatistician with the company.&lt;/p&gt;&lt;p&gt;Bolger reported no conflicts of interests.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_361"
                     title="Hidden Dangers of Herbal Meds Reviewed"
                     score="0.011"
                     href="http://www.medpagetoday.com/PrimaryCare/AlternativeMedicine/tb/18244?impressionId=1265745575779"
                     
      Herbal medicines are not always the harmless nostrums that many patients and even some physicians think, but may actually contribute to cardiovascular morbidity and mortality, researchers warned in a review covering 44 years of research into the subject.&lt;br&gt;
&lt;br&gt;Many such products, including aloe vera, ginkgo biloba, ginseng, and green tea, can interact with conventional cardiovascular drugs and lead to serious adverse reactions, according to Arshad Jahangir, MD, of the Mayo Clinic in Scottsdale, Ariz., and two other Mayo physicians.&lt;br&gt;
&lt;br&gt;&quot;There is a clear need for better public and physician understanding of herbal products through health education, early detection and management of herbal toxicities, scientific scrutiny of their use, and research on their safety and effectiveness,&quot; they wrote in the Feb. 9 &lt;em&gt;Journal of the American College of Cardiology&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;Jahangir and colleagues also called for increased regulation of such products, at least requiring manufacturers of herbal medicines to register with the FDA and provide evidence of good manufacturing practices.&lt;/p&gt;
&lt;p&gt;&quot;Some of these adverse drug reactions are preventable,&quot; Jahangir told &lt;em&gt;MedPage Today&lt;/em&gt; in a telephone interview. &quot;Simple things like taking a good history or giving that history and discussing these issues, probably we can avoid [such reactions].&quot;&lt;/p&gt;
&lt;p&gt;Other physicians contacted by &lt;em&gt;MedPage Today&lt;/em&gt; and ABC News agreed that the growth in popularity of herbal medicines poses problems for physicians and patients.&lt;/p&gt;
&lt;p&gt;&quot;Because these remedies are &apos;natural,&apos; their potential dangers are not considered the same way they would be if they were medication,&quot; commented Suzanne Steinbaum, MD, a cardiologist at Lenox Hill Hospital in New York City, in an e-mail.&lt;/p&gt;
&lt;p&gt;&quot;For many reasons, patients tend not to disclose to their doctors if they are taking herbal remedies, including fear that their doctors won&apos;t approve or they will be told to stop them,&quot; Steinbaum added. &quot;This lack of knowledge and full-disclosure, for some, might be a fatal omission.&quot;&lt;/p&gt;
&lt;p&gt;Jahangir and colleagues reviewed nearly 90 publications that have addressed herbal or complementary therapies and cardiovascular effects since 1966.&lt;/p&gt;
&lt;p&gt;Their &lt;em&gt;JACC&lt;/em&gt; article listed 15 common herbal medicines known to interact adversely with conventional cardiovascular drugs.&lt;/p&gt;
&lt;p&gt;In many cases, the herbal products compete with the regular medicines for the same drug-metabolizing cytochrome P450 enzymes, potentiating the latter&apos;s effects. In other cases, the herbal products have their own cardiovascular effects.&lt;/p&gt;
&lt;p&gt;Many physicians already know that grapefruit juice occupies the CYP3A4 enzyme, leading to slower-than-expected metabolism and, therefore, higher blood levels of a host of pharmaceuticals.&lt;/p&gt;
&lt;p&gt;These include the statins, calcium channel antagonists, several common anti-arrhythmic drugs, and the angiotensin receptor blocker irbesartan (Avapro), Jahangir and colleagues noted.&lt;/p&gt;
&lt;p&gt;Garlic is one of several common herbal remedies with specific cardiovascular effects in its own right (others include ginkgo biloba, ginseng, and saw palmetto). Garlic inhibits platelet aggregation and thus can lead to increased bleeding risks when combined with aspirin, clopidogrel (Plavix), or warfarin (Coumadin), the researchers noted.&lt;/p&gt;
&lt;p&gt;The Mayo group identified 10 herbal products that increase bleeding risks with anticoagulant and antiplatelet drugs, as well as 14 that can induce arrhythmias.&lt;/p&gt;
&lt;p&gt;In all, Jahangir and colleagues listed 27 herbal products that patients with cardiovascular diseases would do well to avoid. These include such common and harmless-seeming products as green tea, capsicum pepper, licorice, and kelp, as well as grapefruit juice and garlic.&lt;/p&gt;
&lt;p&gt;&quot;We need to check with our patients what type of products they are using, to identify these potential interactions,&quot; Jahangir told &lt;em&gt;MedPage Today&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;He cited the previously reported figure of 100,000 deaths annually from drug interactions, adding, &quot;We don&apos;t even know how many of these are due to use of compounds that we are not aware that our patients are taking.&quot;&lt;/p&gt;
&lt;p&gt;Jahangir said he was surprised, in preparing the review, at the scale of hebal medicine use in the U.S.&lt;/p&gt;
&lt;p&gt;He and his colleagues found data from the 1990s suggesting that more patients consult complementary and alternative medicine providers than regular physicians.&lt;/p&gt;
&lt;p&gt;The total annual out-of-pocket expenditure on complementary and alternative medicine services and products also was greater than for conventional physician services.&lt;/p&gt;
&lt;p&gt;&quot;The surprise for me was . . . how much people are willing to spend on a type of therapy which has not shown, in any scientific way, to be effective or safe,&quot; Jahangir said.&lt;/p&gt;
&lt;p&gt;He added that the trend may reflect shortcomings of the conventional medical system.&lt;/p&gt;
&lt;p&gt;&quot;What is the reason people are going there? Is it because there is some unmet type of need that we are not recognizing as practitioners of conventional medicine?&quot;&lt;/p&gt;
&lt;p&gt;Jahangir said it may be that physicians aren&apos;t spending enough time with patients to understand their true needs. He said it appears that, &quot;despite the advancement in our technology and new medicines, there is a demand for alternative therapies that is increasing.&quot;&lt;/p&gt;
&lt;p&gt;He recommended that, in addition to asking patients in detail about herbal and other alternative therapies they may be using, physicians should educate themselves on what these therapies purport to do and what is known about their real biological effects.&lt;/p&gt;
&lt;p&gt;The &lt;a href=&quot;http://nccam.nih.gov&quot; mce_href=&quot;http://nccam.nih.gov&quot; target=&quot;_blank&quot;&gt;National Center for Complementary and Alternative Medicine&lt;/a&gt; at the National Institutes of Health is a good starting point for such information, both for physicians and for patients, Jahangir said.&lt;/p&gt;
&lt;p&gt;Lenox Hill&apos;s Steinbaum said it was important that conventional physicians &quot;become more open-minded and accepting&quot; of alternative medicine, if only because so many of their patients are already practicing it.&lt;/p&gt;
&lt;p&gt;David Meyerson, MD, JD, a Johns Hopkins University cardiologist, told &lt;em&gt;MedPage Today&lt;/em&gt; and ABC News in an e-mail that he advises patients to limit their use of &quot;unstudied and unproven and FDA-unregulated herbal medications.&quot;&lt;/p&gt;
&lt;p&gt;&quot;It&apos;s unfortunately very big business, and potential drug interactions and potential harmful effects abound,&quot; he wrote.&lt;/p&gt;
&lt;p&gt;But another physician criticized the Mayo physicians&apos; emphasis on adverse effects in their review.&lt;/p&gt;
&lt;p&gt;&quot;For many of products listed, evidence for side effects seems to be minimal,&quot; Scott Grundy, MD, of the University of Texas Southwestern Medical Center in Dallas, argued in an e-mail.&lt;/p&gt;
&lt;p&gt;He agreed that the efficacy and safety of such drugs remains largely unproven, but added, &quot;It is mainly for these reasons that they cannot be recommended for use.&quot;&lt;/p&gt;
&lt;p&gt;Creating alarm about side effects &quot;may not be the appropriate way to discourage their use,&quot; Grundy said.&lt;/p&gt;
&lt;p&gt;&lt;em&gt;This article was developed in collaboration with ABC News. &lt;/em&gt;&lt;img src=&quot;http://www.medpagetoday.com/upload/2009/10/1/14357_1.jpg&quot; mce_src=&quot;http://www.medpagetoday.com/upload/2009/10/1/14357_1.jpg&quot; alt=&quot;&quot;&gt;&lt;/p&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_311"
                     title="Long QT Syndrome Diagnosis Aided by Standing ECG (CME/CE)"
                     score="0.006"
                     href="http://www.medpagetoday.com/Cardiology/Arrhythmias/tb/18178?impressionId=1265745575779"
                     
      A brief acceleration of the heart rate when a patient stands up quickly may help diagnose long QT syndrome, researchers found.&lt;br&gt;
&lt;br&gt;The sudden movement provokes a short-lived tachycardia, which allows documentation of the characteristic QT prolongation on the electrocardiogram of affected patients, according to Sami Viskin, MD, of Tel-Aviv Medical Center in Israel, and colleagues.&lt;br&gt;
&lt;br&gt;The response of the QT interval to this tachycardia induced by this simple maneuver was a shortening by 21 ms in normal individuals, on average, compared with an average increase of 4 ms in long QT patients (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.001), Viskin&apos;s group reported online in the &lt;em&gt;Journal of the American College of Cardiology&lt;/em&gt;.&lt;br&gt;
&lt;br&gt;Adding the test to routine ECG evaluation improved diagnostic ability in the study, they concluded.&lt;br&gt;
&lt;br&gt;&quot;This is a very simple maneuver that anyone can do that will help diagnose patients with long QT,&quot; Douglas Zipes, MD, of Indiana University, a past president of the ACC, told &lt;em&gt;MedPage Today&lt;/em&gt;.&lt;p&gt;&lt;/p&gt;
&lt;p&gt;Other diagnostic methods to provoke arrhythmia in diagnostic workup of long QT syndrome include an exercise test on the treadmill or infusion of a drug such as epinephrine, although ultimately a genetic test is often conducted.&lt;/p&gt;
&lt;p&gt;Zipes agreed with the researchers that &quot;you don&apos;t hang everything on this  --  this is simply something that you add to your overall evaluation of the potential long QT patient.&quot;&lt;/p&gt;
&lt;p&gt;But patients with long QT shouldn&apos;t be concerned that standing will bring on arrhythmia, Zipes cautioned. &quot;I don&apos;t think there&apos;s any danger in that,&quot; he said.&lt;/p&gt;
&lt;p&gt;The study included 68 patients with definite or highly probable long QT syndrome (46% with the LQT1 mutation, 41% with the LQT2 mutation, 4% with the LQT3 mutation, and 9% unsuccessfully genotyped). Testing was conducted 26 to 30 hours after the last dosage of beta-blockers for any patients taking them.&lt;/p&gt;
&lt;p&gt;Another 82 similarly-aged, healthy volunteers and asymptomatic relatives of long QT patients without familial mutation were included as controls. None was using medications.&lt;/p&gt;
&lt;p&gt;All had a baseline ECG while lying down for 10 minutes and, while still hooked up for continuous recording, were then asked to get up quickly and stand still for five minutes.&lt;/p&gt;
&lt;p&gt;The researchers found a similar acceleration in heart rate upon standing in the two groups.&lt;/p&gt;
&lt;p&gt;But the response of the QT interval differed during maximal sinus tachycardia for long QT syndrome patients and controls.&lt;/p&gt;
&lt;p&gt;Among controls, 59% had a shortening of at least 20 ms in their QT interval, while 39% had less than a 20 ms change, and only 2% had an increase of at least 20 ms.&lt;/p&gt;
&lt;p&gt;Among long QT cases, just 24% had a drop in QT interval while 34% had an increase (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.001 versus controls). The remainder were unchanged.&lt;/p&gt;
&lt;p&gt;The QTc interval was already different between groups at baseline. But the difference increased during standing &quot;since the QT interval decreased less than the RR interval during standing-induced tachycardia.&quot;&lt;/p&gt;
&lt;p&gt;The QTc interval increased during maximal tachycardia by only 50 ms (13% from baseline) in controls, compared with 89 ms (20% from baseline) in long QT patients (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.001).&lt;/p&gt;
&lt;p&gt;At the point of maximal QT interval stretching, the QTc interval rose by 54 ms in controls, versus 94 ms in affected patients (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.001).&lt;/p&gt;
&lt;p&gt;Even after excluding long QT syndrome patients with &quot;very long&quot; baseline QT intervals or unknown genotype, the differences between controls and cases were statistically significant.&lt;/p&gt;
&lt;p&gt;The effect was particularly apparent in patients with the LQT2 mutation.&lt;/p&gt;
&lt;p&gt;Area under the receiver-operating characteristic curves showed incremental diagnostic value to the test, the researchers said.&lt;/p&gt;
&lt;p&gt;In one analysis, these curves of QT and QTc intervals at maximal heart rate showed significantly better diagnostic accuracy than those at baseline (&lt;em&gt;P&lt;/em&gt;=0.008 and &lt;em&gt;P&lt;/em&gt;=0.026, respectively).&lt;/p&gt;
&lt;p&gt;The authors noted that some individuals in the control group had QT interval stretching in response to standing similar in magnitude to those with long QT syndrome.&lt;/p&gt;
&lt;p&gt;While these &quot;outliers&quot; might represent false positives with the standing test, the investigators suggested further research to examine whether they might have repolarization reserve abnormalities.&lt;/p&gt;
&lt;p&gt;&quot;Accurate diagnosis of the long QT syndrome is crucial because this is a potentially lethal disorder for which effective therapy exists,&quot; Viskin&apos;s group wrote.&lt;/p&gt;
&lt;p&gt;They cautioned that baseline T-wave morphology and QT interval may have unblinded the investigator in some cases, leading to the possibility of biased measurements.&lt;/p&gt;
&lt;p&gt;They also warned against overinterpreting the standing test results in isolation.&lt;/p&gt;
&lt;p&gt;Another technical issue to be aware of is that movement may create an artifact in the ECG, so making sure patients stand very still after rising would be important, Zipes added.&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 a grant from by the Netherlands Heart Foundation. The researchers provided no information on conflicts of interest.&lt;/p&gt;&lt;p&gt;Zipes reported no relevant 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_297"
                     title="Ablation Therapy Controls Atrial Fibrillation (CME/CE)"
                     score="0.005"
                     href="http://www.medpagetoday.com/Cardiology/Arrhythmias/tb/18152?impressionId=1265745575779"
                     
      If initial drug therapy fails to control paroxysmal atrial fibrillation, the next step should be radiofrequency catheter ablation, researchers said.&lt;br&gt;
&lt;br&gt;In a prospective randomized trial, catheter ablation succeeded in preventing fibrillation and other forms of treatment failure in 66% of patients, according to David J. Wilber, MD, of Loyola University Medical Center in Maywood, Ill., and colleagues.&lt;br&gt;
&lt;br&gt;By comparison, only 16% of patients who got renewed drug therapy were free from treatment failure by the end of nine months of follow-up, Wilber and colleagues reported in the Jan. 27 issue of the &lt;em&gt;Journal of the American Medical Association&lt;/em&gt;.&lt;br&gt;
&lt;br&gt;The trial was stopped early, in fact, after a Bayesian analysis showed the predictive probability of success for the catheter treatment to be 99.9%.&lt;p&gt;&lt;/p&gt;
&lt;p&gt;The study &quot;confirmed resoundingly&quot; that catheter ablation is the way to go after a patient has failed an initial attempt to control the heart rhythm with drugs, Wilber told &lt;em&gt;MedPage Today&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;&quot;This is really a procedure that&apos;s come of age,&quot; he said.&lt;/p&gt;
&lt;p&gt;Although anti-arrhythmic drugs are the usual first-line therapy, they are only inconsistently effective, Wilber said  --  about half of all patients will have a recurrence of fibrillation within six months to a year.&lt;/p&gt;
&lt;p&gt;Also, he said, the drugs have a range of adverse events associated with them that range from nuisance effects, such as dizziness, to more serious consequences, such as inflammation of the liver, lung, or thyroid.&lt;/p&gt;
&lt;p&gt;Several smaller studies have suggested that catheter ablation is more effective and has fewer adverse events, but Wilder and colleagues conducted a study that eventually analyzed results in 167 patients from several centers in the U.S. and elsewhere.&lt;/p&gt;
&lt;p&gt;The primary endpoint was freedom from symptomatic atrial fibrillation, although total atrial fibrillation was also measured. The protocol also defined treatment failure in some other cases, including a need for a repeat ablation procedure more than 80 days after the first.&lt;/p&gt;
&lt;p&gt;Patients were eligible for the study if they did not respond to at least one anti-arrhythmic drug and had experienced at least three symptomatic fibrillation episodes within the six months before randomization, the researchers reported in the journal.&lt;/p&gt;
&lt;p&gt;Most of those randomized to the drug therapy arm of the study were treated with either flecainide (Tambocor) or propafenone (Rythmol).&lt;/p&gt;
&lt;p&gt;Analysis showed that, at the end of the nine-month effectiveness evaluation period: &lt;ul&gt; &lt;li&gt;66% of patients in the ablation group remained free from protocol-defined treatment failure compared with 16% of those treated with drugs. The hazard ratio was 0.30 (with a 95% confidence interval from 0.19 to 0.47, which was significant at &lt;em&gt;P&lt;/em&gt;&amp;lt;0.001). &lt;/li&gt; &lt;li&gt;70% of ablation patients had no recurrences of symptomatic atrial arrhythmia compared with 19% of those getting drugs. (The hazard ratio was 0.24, with a 95% confidence interval from 0.15 to 0.39, which was significant at &lt;em&gt;P&lt;/em&gt;&amp;lt;0.001). &lt;/li&gt; &lt;li&gt;63% of patients treated by ablation were free of any recurrent atrial arrhythmia, symptomatic or not, compared with 17% of those treated with drugs. (The hazard ratio was 0.29; with a 95% confidence interval from 0.18 to 0.45, also significant at &lt;em&gt;P&lt;/em&gt;&amp;lt;0.001).&lt;/li&gt; &lt;/ul&gt;&lt;/p&gt;
&lt;p&gt;Major treatment-related adverse events within the first 30 days occurred in 8.8% of patients treated with drugs and 4.9% of those treated with catheter ablation, the researchers said.&lt;/p&gt;
&lt;p&gt;The study has some limitations, the researchers said, including the fact that most of the investigators had considerable experience with the ablation procedure. Outcomes in centers with less experience may vary, they said.&lt;/p&gt;
&lt;p&gt;In addition, the study did not address longer-term outcomes such as mortality, risk of stroke, heart failure, or progression of atrial fibrillation into a more persistent arrhythmia.&lt;/p&gt;
&lt;p&gt;The researchers also noted that study volunteers were relatively young and had less cardiovascular comorbidity than most people with paroxysmal atrial fibrillation. The result may not generalize to patients with significant left ventricular dysfunction, more persistent forms of fibrillation, or advanced heart failure, they 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;The study was supported by funded by Biosense Webster, which provided the catheters used.&lt;/p&gt;&lt;p&gt;Wilber reported financial links with Biosense Webster, Boston Scientific, Medtronic, St. Jude Medical, sanofi-aventis, and Blackwell/Futura. Most other authors reported financial links with a range of industrial organizations, including Biosense Webster. Two authors are employees of the company.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
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