Research in Experimental Medicine

, Volume 189, Issue 5, pp 363–370 | Cite as

Acute induction of sustained ventricular tachycardia: A new porcine model

  • C. Schmid
  • J. Nitsch
  • B. Lüderitz
Original Papers

Summary

In this study we evaluated the possibility of initiating long-lasting ventricular tachycardias acutely, using isolated porcine hearts and thus avoiding an open-chest operation model. This set-up was designed especially to investigate defibrillating or antitachycardiac pacing devices, which terminate these malignant arrhythmias if medical treatment fails.

The experiments were performed on 42 pigs, weighing 20–25 kg. After thoracotomy their hearts were removed and adapted to a Langendorff perfusion system. Supplied with their own blood, beating hearts were manipulated in three different ways: direct current impulses (4.5 V, 750 ms) or programmed ventricular stimulation, creation of a small myocardial infarction, and application of antiarrhythmic drugs (ajmalin, lidocaine, sotalol). Out of all possibilities the combination of ajmalin (mean concentration 0.041 µg/ml) and a small anteroapical myocardial infarction (3–6 cm2) along with direct current impulses (4.5 V), led to sustained ventricular tachycardias in the highest proportion (93%) of trials (P < 0.001). The heart rate was 251 beats per minute on average. Lidocaine trials were less successful (53%), while programmed ventricular stimulation and sotalol failed to induce ventricular tachycardias. This study supports the evidence that the combination of ajmalin and a small myocardial infarction with direct current impulses is a reliable model for sustained ventricular tachycardias in isolated pig hearts. Although it is a rather artificial organ model, tachycardias can be induced acutely without any long-term pretreatment. Animal models based on chronic myocardial infarctions will therefore be unnecessary for the investigation of defibrillating systems and antitachycardiac pacing devices.

Key words

Ventricular tachycardia Antiarrhythmic drug Isolated pig heart Langendorff perfusion 

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Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • C. Schmid
    • 1
  • J. Nitsch
    • 2
  • B. Lüderitz
    • 2
  1. 1.Dept. of Thoracic and Cardiovascular SurgeryHannover Medical SchoolHannoverFederal Republic of Germany
  2. 2.Dept. of CardiologyUniversity of BonnBonnFederal Republic of Germany

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