Читать книгу Practical Cardiovascular Medicine - Elias B. Hanna - Страница 135

There are two types of VT:

 Polymorphic VT is usually an ischemic rhythm that occurs in the first 48 hours of MI or during ischemic recurrences.¹⁴⁰ In contrast to torsades de pointes, this polymorphic VT is usually associated with a normal or a minimally prolonged QT interval. Similar to primary VF, it is associated with increased short-term but not long-term mortality.¹⁴¹

 Monomorphic VT, whether occurring early (in the first 48 hours) or late (>48 hours), is a sign of extensive myocardial damage and por- tends a strikingly increased in-hospital but also long-term mortality, even when it is not accompanied by HF or shock (GUSTO-1 data).135,142,143 It is rarely seen, in ~2% of MI.

Polymorphic VT usually corresponds to active ischemia, many times without underlying anatomic substrate/scar or with less underlying anatomic substrate and higher EF than monomorphic VT.¹⁴⁴ Monomorphic VT, on the other hand, usually reflects the presence of an often large scar and originates in the border zone between viable and infarcted tissue.¹³⁵