Testing for Troponin-T in Potential
Myocardial Infarction Patients
By Daryl Shaw, Medical Student

The following is a synopsis of an article in the May/June issue of RETTUNGSMAGAZIN. I have condensed and translated it and will include additions re: muscle/cardiological physiology for easier understanding.:

More than 250,000 persons suffer an AMI per year in Germany. Approx. 20% of these expire within 2 hours of ischamic begin. For this reason, it was of great importance that an objective test be found to confirm or indicate AMI in the preclinical (EMS) theater.

It was discovered that the cardial enzyme Troponin-T, a deciding factor in the Actin-Myosin contractile system typical to all muscles, especially striped muscle and, histologically related, cardial myocardial muscle. The component Troponin-T of the Actin strand is responsible, along with Tropomyosin, for the contraction in the individual muscle strand, in that they interact with calcium to allow or block the contraction cycle.

It has been determined that ischemia results in the release of Troponin-T from the damaged area of the myocard, whereby concentrations above 0.2 ng/ml blood are pathological and can be illustrated with the test.

The best situation for the use of the test is AMI suspect patients where ECG conformation is not definite or the symptomatic picture is "unappropriate". Dr. Motschwiller from Boehringer Mannheim stresses the fallicy of sole usage for AMI diagnosis, "The Tropt-Test should not be overestimated...(it) is primarily for the conformation of a suspected (AMI) diagnosis"(Due to individual cardiovascular kinetics and release rate, enzyme conformation may take up to 30 mins. after ischemia beginning.).

The test is composed of documentation card, test stick and syringe. 150 microliter anti-coagulated blood (i.e. from blood lab tube/Vacutainer) is put in window of test stick and covered with included flap. The stick is attached to the documentation card and the necessary information including start time is included. After "a few" (5) minutes a result can be visually registered; 1 stripe (control): negative , 2 stripes: positive. When negative, a waiting period of 20 minutes is advisable (kinetics). This test is only of qualitative value; a quantitive evaluation must be done in the treating facility. Due to the kinetics of release, a negative test result can occur up to 12 hours post ischemia.

Finally, there is the problem of storage; the test must be kept between 2 and 8 degrees celsius and only is good for a week at room temperature, hence the need for a cool storage area, i.e. a refridgerator.

The tests cost DM 179,98 for 10 sets or DM 100,40 for 5 Sets.

Contact Address:

Boeringer Mannheim
Dr. E. Motschwiller
Sandhofer Strasse 116
68298 Mannheim GERMANY

Author's note:

Obviously, the arena in the U.S. differs from ours. We (rarely) use a First Responder system, and due to legalities, the EMS physician is on scene within 15 minutes. The closest hospital is (for us) anywhere between 5-10 mins. away, whereby I can be in 6-8 hospitals within 15-20 mins. Perhaps the most aggrevating item is that , technically, we cannot perform ANY invasive procedures, including i.v. admin. with LR or NSS. Luckily, most Drs. are open to anybody willing to help. On the local level (see first response), anything above the most basic Advanced First Aid is forbidden, and doing anything above that is costly to your life span in the org., even if it was "appropriate" ( I speak from experience! ) or you are trained to do more than the rest (as I am) or you know better (AHEM!!). Therefore, I do not believe anybody below the medical level will gain very much (EMS) experience with the Troponin-T test unless major changes are made.

Daryl Shaw Stud.med./Rett.Ass. Zwingenberg, Germany

(P.S.: pardon my English, I'm new at this...Thank you.)