CABG following an attempted primary PCI

What are the situations in which patient is taken up for coronary artery bypass grafting (CABG) following an attempted primary percutaneous coronary intervention (PCI)?

CABG following an attempted primary PCI may be considered when:

  1. Coronary anatomy not suitable for PCI
  2. Coronary artery perforation
  3. Inability to cross a critical lesion causing recurrent ischemia

But these indications are not always definite indications for CABG as the PCI technology is evolving. Many of the lesions which were not considered suitable for PCI are now amenable with the availability of newer hardware and operator expertise.

Coronary perforations can be tackled in the cathlab with covered stents, avoiding an emergent CABG as well as improving the prognosis as the time lag for emergent CABG is always significant and can cause significant hemodynamic deterioration in between.

Inability to cross critical lesions have also become less often due to better hardware, newer techniques of PCI and ancilliary devices as well as better operator experience in tackling difficult lesions.

In general, CABG is utilised in only about 5% cases of acute myocardial infarction as other modalities of reperfusion like thrombolysis and PCI provide much faster restoration of coronary blood flow, whereas CABG is always associated with unavoidable delays [1]. It may be noted that urgent CABG may be needed for mechanical complications of acute myocardial infarction like  acute mitral regurgitation, rupture of the interventricular septum and rupture of the left ventricular free wall.

Reference

  1. William Y. Shi and Julian A. Smith. Chapter 16: Role of Coronary Artery Bypass Surgery in Acute Myocardial Infarction. Primary Angioplasty: A Practical Guide [Internet]. Watson TJ, Ong PJL, Tcheng JE, editors. Singapore: Springer; 2018.