Link found between adenovirus infection and left-ventricular failure

How can trials in back surgery be done? straw poll done at a combined meeting of four spinal societies (BritSpine 99, Manchester, UK; March 3–5) showed that none of 220 orthopaedic and neurosurgical spinal surgeons present had had surgery for back problems, and only a few would contemplate such surgery. Perhaps this result indicates the need for definitive proof that spinal surgery works. Trials of back surgery are few and far between. Randomised Aiming straight controlled trials are rare for surgical techniques as a whole, and only about 10% of all surgical trials are for back surgery, said Jeremy

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Fairbank, Nuffield Orthopaedic Centre, Oxford, UK. Blinding in such trials is almost impossible, he explained. In addition, placebo treatment is unethical, and there is variation in surgeon skill, which confounds the results. Gordon Waddell, Glasgow Nuffield Hospital, UK, reported results of a Cochrane review of seven surgical trials in lumbar spondylosis, soon to be published in Spine. The most striking finding, he said, was that most outcome measures were surgical measures assessed by the surgeon, and that very little attention was paid to patients’ assessment of the

results. What is needed, he said, is objective assessment of outcome by independant physicians, rehabilitation or occupational health specialists, or general practitioners. Hardly any of the trials were blinded for assessment of outcome, he continued. Also, the views of patients were seldom sought. The evaluation of disability should include patients’ reports of pain or disability, he stressed, as well as an objective clinical assessment, which should be made 2 years after intervention. Waddell concluded that the days of surgeons deciding that they are satisfied with their results “are over or running out”. Surgeons need to “start looking carefully and honestly at what patients think and how outcomes affect the patient”. Stephanie Clark

Mother Nature inspires new treatments for myocardial infarction

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ardiologists attending the American College of Cardiology meeting (New Orleans, LA, USA; March 7–10) found inspira tion from nature in the battle against myocardial infarction (MI). Straight from the sea came the concept of fish-oil supplements. A new study from the Gruppo Italiano per lo Studio della Sopravivenza nell’Infarto Miocardico—GISSIPrevenzione study—found they were efficacious in preventing re current MI. More than 11 000 sur vivors of heart attack were given omega-3 fish-oil supplements, vita min E, both, or neither. After 3·5 years, mortality, non-fatal MI,

and non-fatal stroke was 12·4% for those who received the fish-oil sup plement and 13·7% for those who did not. This significant difference was because of a decrease in allcause mortality, reported Franco Valagussa (Milan, Italy). The evi dence for a benefit from vitamin E was not significant. “It’s difficult to beat Mother Nature”, admitted Frans van de Werf (University Hospital, Leuven, Belgium), commenting on two studies comparing two new throm bolytic agents with tPA (tissue-type plasminogen activator), nature’s own clot buster. Both new agents are tPA mutants. In the Assessment

of the Safety and Efficacy of a New Thrombolytic Agent (ASSENT 2) trial, 16 950 patients with acute MI received tPA or TNK-tPA (tenecte plase). At 30 days, mortality was 6·2% in both groups, with no signif icant differences in major events. In the Intravenous nPA for Treatment of Infarcting Myocardium Early (InTIME) trial 15 078 patients with acute MI were assigned nPA (lanoteplase) or tPA. Mortality at 30 days was 6·77% and 6·60%, respectively. A drawback to nPA was an excess of intracranial haemorrhages (1·13% vs 0·62%). Larry Husten

Link found between adenovirus infection and left-ventricular failure lthough it has been known for some time that enteroviral infections can lead to myocarditis and dilated cardiomyopathy in adults and children, many experts thought that adenoviral infection was a risk factor restricted to children. Jeffrey Towbin (Baylor College of Medicine, Houston, TX, USA) became convinced that this second group of viruses could also predispose adults to left ventricular dysfunction and sudden death and set out to prove it. Matthias Pauschinger and HeinzPeter Schultheiss (Benjamin Franklin Free University, Berlin, Germany) worked with the Baylor team to assay

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heart-biopsy samples from 94 adult patients with idiopathic left ventricular dysfunction and 14 controls. They used the nested PCR to look for the presence of adenoviral DNA and enteroviral RNA and did histological tests to detect myocardial inflammation. None of the patients had myocarditis but 12 of the 94 were postive for adenovirus and a further 12 were positive for enterovirus. Neither virus was found in controls (Circulation 1999; 99: 1348–54). Nicholas Peters (St Mary’s Hospital, London, UK) finds the results “of great interest”, but warns that “care must be taken not to inter-

pret the results as confirming a causeand-effect relationship. With only 14 controls it remains possible that there is a higher prevalence of virus particles than the sampling failed to detect”. In response Towbin explains that although the paper only discusses 14 controls, his team have assayed several hundreds of control samples in the same way, with the same negative results. He remains convinced of his theory and recommends immunisation against selected adenoviruses and enteroviruses to reduce the risk in future generations. Kathryn Senior

THE LANCET • Vol 353 • March 20, 1999