TO THE EDITOR: I would like to clar...

TO THE EDITOR: I would like to clarify a certain of the recommendations from the article, "transient ischemic Attacks: Part I. diagnosis and evaluation, (1)" that appeared in American Family Physician. the authors advocate early referral to the unforeseen occasion department for evaluation and potential treatment with tissue-type plasminogen activator (tPA). they also place this recommendation in their algorithm (Figure 1 (1)) transient ischemic attack (TIA) is not an indication for tPA administration; solitary confirmed strokes have received this indication. In fact, rapidly improving symptoms, as can offer with TIAs, are a contraindication to the administration of tPA.

Further, there has been to a great degree discussion about the role of tPA in patients who have put up withed a stroke. Many authorities frequently quote a 30 percent reduction in disability with this intervention. For the record, the National institute of Neurological diseases and misfortune (NINDS) study group demonstrated a 12 percent absolute reduction in disability (number be in want ofed to treat [NNT] = 8) (2) the 30 percent figure that ofttimes is quoted (including in the Advanced Cardiac Life Support provider manual (3)) is relative risk reduction, which is a statistic that is commonly enlist in one's serviceed to exaggerate the benefits of an intervention. Further, it is always important to point on the outside the harm associated with tPA administration in pat patients. NiNdS demonstrated a 6 percent deterioration caused through intracranial hemorrhage (NNt = 16) the use of tPA in the community hospital setting has been demonstrated to be fraught with enigmas (4)

I agree with the popular conclusions of the Cochrane Collaboration: "the data are promising and may justify the use of thrombolytic therapy with intravenous recombinant tissue plasminogen activator in experienced middles in highly selected patients where a [license] exists. however, the data do not support the widespread use of thrombolytic therapy in routine clinical practice at this time, nevertheless suggest that further trials are straited to identify which patients are most numerous likely to benefit from treatment and the environment in which it may best be given." (5)

ROBERT DACHS, MD

Department of sudden [i]or[/i] unexpected occurrence Medicine and Family Practice

St Clare's Hospital

600 McClellan St

Schenectady, NY 12304

REFERENCES

(1) Solenski NJ Transient ischemic attacks: part I. Diagnosis and evaluation. Am Fam Physician 2004;69:1665-74

(2) Tissue plasminogen activator for acute ischemic misfortune National Institute of Neurological Disorders and hit rt-PA Stroke Study Group. N Engl J M 1995;333: 1581-7

(3) Cummins RO Field JM Hazinski MF Babbs CF American Heart Association. ACLS provider manual. Dallas, Tex: American Heart Asssociation, 2001:202

(4) Bravata DM Kim N Concato J Krumholz HM Brass LM Thrombolysis for acute blow in routine clinical practice. Arch Intern M 2002;162:1994-2001

(5) Wardlaw JM del Zoppo G Yamaguchi T Berge E Thrombolysis for acute ischaemic hit Cochrane Database Syst Rev 2005;(1):CD00213

IN REPLY: I thank Dr Dachs for his interest in the article. (1) We are in agreement that a patient with an accurately diagnosed resolv transient ischemic attack (TIA), defined at the current criteria (transient cerebral ischemic deficit lasting for at least undivided hour) or by the traditional definition (lasting for at least 24 hours), is not a candidate for tissue-type plasminogen activator (tPA) in the nonacute setting. At the time of an acute cerebral ischemia consequence to which the algorithm pertains, the evaluating physician has no way of predicting if the deficit will clear or if it will remain permanent, and, therefore, this presentation could be a TIA or a shock For this reason, it is appropriate to evaluate a patient who at hands with acute symptoms lasting les than 180 minutes for treatment with intravenous tPA regardless of whether the patient ultimately is diagnosed with a TIA or pat the National institute of Neurological diseases and hit (NINDS) trial for tPA in acute misfortune contained a placebo limb and a treatment limb that consisted of potential TIAs and thump patients. It is not appropriate to wait for patients to clear their symptoms of TIA in the acute setting because "time is brain." As Dr Dachs points not at home rapidly improving symptoms or signs may indicate resolution of the cerebral ischemia, in which case the risks of intravenous tPA outweigh the benefits. Interestingly, there are data to give an inkling of that although patients might be exclud at the time of initial evaluation for intravenous tPA upon the basis of "mild or significantly improving neurologic symptoms," 32 percent of in the same state [i]or[/i] condition patients in one study were imagineed dependent at discharge (or deceased). (2)

My article (1) was a review of the evaluation and treatment of TIA and not of the evaluation or treatment of acute visitation the points that Dr. Dachs makes about the administration of tPA for acute rap are well addressed in a previous article in American Family Physician. (3) this article (3) states "that the use of tPA in community hospitals is feasible and safe as drawn out as the American heart Association (AHA) guidelines and NiNdS protocol are followed." (4) the use of tPA for acute ischemic visitation according to strict guidelines has been endorsed by dint of the AHA Stroke Council [now the American hit Association] and the American Academy of Neurology the U sustenance and drug Administration approved tPA 11 years ago, and after more than a decade of experience and use, intravenous tPA remains endorsed on these and other related foundations and academies.