**9. Current trends in PCI versus CABG in North America**

The practice patterns regarding PCI and CABG have changed dramatically within the last 10-15 years. In the earlier part of this last decade, rates of PCI have been observed to be on the rise both in the United States and in Canada despite relatively more static rates of CABG over that same period [75, 76]. Furthermore, although there is some signal that the trend in PCI rates have begun to plateau or reverse in the latter part of this decade both in the United states and in Canada, there is still a consistent increase in the overall PCI: CABG ratio [77, 78].

These recent trends have been an area of increasing research interest, as it seems paradoxical in the context of relatively consistent practice guidelines from the ACC and the ESC supporting the use of CABG as the first line mode of revascularization in prognostically important stable

**Figure 9.** Variation in Revascularization for Multivessel Disease Across 17 Cardiac Centers in Ontario. Reproduced with permission from Schwalm JD et al. SYNTAX Score and Real World Revascularization Patterns. Canadian Cardiovascular Congress 2011 Vancouver, BC. Abstract Presentation.

ischemic coronary artery disease [Figure 9] [14, 26]. In fact, recent data has demonstrated a rise in PCI with DES in patients with Class I recommendation for surgery [25].

SignificantvariabilityinPCI:CABGratiobetweenprovinces/states,betweenhospitalsandeven betweenindividualinterventionalists suggests thatthe trends inrevascularizationpractices are not entirely explained by changes in population or advancements in revascularization techniques [76-80].InOntario,Canada,PCItoCABGratiosvaryconsiderablybetweenhospitals from 1.3 to 6.1 [81]. In multivessel disease, this ratio ranges from 0.24 to 5.0 [figure 9] [82]. The physician performing the diagnostic catheterization (interventional cardiologist versus noninterventional cardiologist), the coronary anatomy (LM, 3VD, 2VD), and the treating hospital were the three strongest determinants of the ultimate therapeutic strategy [58].

**9. Current trends in PCI versus CABG in North America**

intervention. NEJM 2009. 360(3):213-224.

338 Artery Bypass

The practice patterns regarding PCI and CABG have changed dramatically within the last 10-15 years. In the earlier part of this last decade, rates of PCI have been observed to be on the rise both in the United States and in Canada despite relatively more static rates of CABG over that same period [75, 76]. Furthermore, although there is some signal that the trend in PCI rates have begun to plateau or reverse in the latter part of this decade both in the United states and

**Figure 8.** Kaplan-Meier Survival Curves according to study group PCI guided by angiography alone versus PCI guided by FFR in addition to angiography. FFR=fractional flow reserve, PCI=percutaneous coronary intervention. Reproduced with permission from Tonino PAL et al. Fractional flow reserve versus angiography or guiding percutanous coronary

These recent trends have been an area of increasing research interest, as it seems paradoxical in the context of relatively consistent practice guidelines from the ACC and the ESC supporting the use of CABG as the first line mode of revascularization in prognostically important stable

in Canada, there is still a consistent increase in the overall PCI: CABG ratio [77, 78].

Two possible hypotheses for the presence of such dramatic variability in the management of multi-vessel disease include misinterpretation of the evidence and misclassification of disease complexity at the time of diagnostic angiogram. There are complex interacting variables upon which the final therapeutic decision is based, including: (1) complexity of coronary anatomy, (2) presence or absence of prognostically important factors favoring surgery, (3) degree of active functional ischemia, (4) complex co-morbid state of patient, (5) patient preferences and social factors, (6) local resources and expertise. All of these factors may affect the patient's suitability for CABG and likelihood to benefit prognostically from surgical revascularization. Application of the large body of evidence in this variable clinical milieu is a complex process. The management algorithm is further complicated when considering the patient's role in the decision-making process and the steps required to ensure truly "informed" patient consent.
