CARP

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McFalls EO, et al. "Coronary-artery revascularization before elective major vascular surgery". The New England Journal of Medicine. 2004. 351(27):2795-2804.
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Clinical Question

In patients with stable CAD undergoing major elective vascular surgery, is there a mortality benefit in preoperative coronary artery revascularization?

Bottom Line

In patients with stable CAD, there is no mortality benefit performing coronary artery revascularization before elective vascular surgery.

Major Points

Patients undergoing elective vascular surgery have a high prevalence of CAD and risk of peri-operative cardiac complications.[1][2] In such patients, clinically significant CAD confers a significant in-hospital and 30-day cardiac mortality rate.[3][4] Prior to CARP, patients with stable CAD often underwent prophylactic preoperative revascularization to lower the risk of cardiac complications when undergoing elective vascular surgery.

The Coronary Artery Revascularization Prophylaxis (CARP) trial compared preoperative coronary artery revascularization to no revascularization. Among 5,859 patients scheduled for elective vascular surgery, 1,190 high risk patients underwent coronary angiogram. Patients with significant LM disease, LVEF ≤20%, or severe aortic stenosis were excluded. The remaining 510 patients (9% of the original cohort) were then randomized to either preoperative revascularization (PCI or CABG) vs. no revascularization. After a median of 2.7 years, there was no difference in the primary outcome of long-term mortality (22% vs. 23% P=0.92). In addition, there was no difference in 30-day postoperative outcomes such as death, MI, stroke, reoperation and LOS.

A major criticism is that high risk patients (patients with severely reduced LVEF, LM and 3VD) who could have benefited from revascularization were excluded, leaving relatively lower risk patients who may not benefit from additional intervention. However, further RCTs in higher risk patients have shown mixed results. The 2007 DECREASE-V Pilot Study[5] randomized 101 high risk patients to revascularization or optimal medical therapy and found no difference in mortality or MI at 30 days or 1 year. On the other hand, the 2009 RCT by Monaco et al. showed that in 208 medium-to-high risk patients there is no short-term benefit to revascularization but potential long-term improvement in mortality and CV events.[6] (The DECREASE trials have mostly been discredited for research misconduct, though the DECREASE-V has not been retracted, the JACC editorial staff warned against trusting the outcomes.)[7]

The 2014 ACC/AHA guidelines maintains the recommendation that preoperative revascularization should be performed only in patients with a pre-existing indication for revascularization.[8]

Guidelines

ACC/AHA guideline on perioperative CV evaluation and management of patients undergoing noncardiac surgery (2014, adapted)[9]

  • Revascularization before noncardiac surgery is recommended in circumstances in which revascularization is indicated according to existing clinical practice guidelines (Class I, level C)
  • It is not recommended that routine coronary revascularization be performed before noncardiac surgery exclusively to reduce perioperative CV events (Class III, level B)

Design

  • Multicenter, double-blind, parallel-group, randomized, controlled trial
  • N=510
    • Preoperative coronary revascularization (n=258)
    • No revascularization (n=252)
  • Setting: 18 VA centers in the US
  • Enrollment: 1999-2003
  • Median follow-up: 2.7 years
  • Analysis: Intention-to-treat
  • Primary outcome: Long-term mortality

Population

Inclusion Criteria

  • Elective vascular surgery for expanding AAA or severe claudication due to PAD
  • ≥1 major coronary arteries with ≥70% stenosis and suitable for revascularization

Exclusion Criteria

  • Urgent or emergent surgery
  • Severe coexisting illness
  • Prior revascularization without evidence of recurrent ischemia
  • Nonobstructive CAD
  • CAD not amenable to revascularization
  • ≥50% stenosis of left MCA
  • LVEF <20%
  • Severe aortic stenosis

Baseline Characteristics

  • Age: 67 years
  • ngina 38%, previous MI 41%, previous CHF 8%, previous TIA/CVA 19%, DM with insulin 19%, current smoker 48%
  • Alb 3.7, Hgb 13.9, TC 179, LDL 106, HDL 37, HgbA1c 6.7%, CRP 0.4, Homocysteine
  • LVEF 55%, 3v CAD 33%, previous CABG 15%
  • Indication for surgery: Abdominal aneurysm 33% or severe symptoms of PAD 67%

Interventions

  • Randomized to either preoperative revascularization or no revascularization (either PCI 59% or CABG 41%) prior to elective major vascular surgery
  • Both arms received standard perioperative medications (85% beta-blockers, 73% aspirin, 54% statins, 93% heparin)
  • Both arms followed-up within 30-days and a year and evaluated with cardiac enzymes, EKG, and echocardiography.

Outcomes

Comparisons are revascularization vs. no revascularization.

Primary Outcomes

All-cause mortality at 2.7 years
22% vs. 23% (RR 0.98; 95% CI 0.70-1.37, P=0.92)

Secondary Outcomes

Post-operative MI within 30 days
Positive enzymes: 11.6% vs. 14.3% (P=0.37)
Positive enzymes and ECG: 8.4% vs. 8.4% (P=0.99)
Stroke within 30 days
0.4% vs. 0.8% (P=0.59)
Limb loss within 30 days
0.4% vs. 2.1% (P=0.11)
Dialysis within 30 days
0.4% vs. 0.4% (P=0.97)
Reoperation within 30 days
7.6% vs. 7.6% (P=0.99)
Total days in the ICU
2 vs. 2 (P=0.25)
Total days in the hospital
6.5 vs. 7 (P=0.29)

Criticisms

  • Patient population largely male (98%) limits generalizability.
  • Majority of study patients had normal LVEF and only one or two vessel disease, which may obscure the benefit of pre-operative revascularization in higher risk patients.

Funding

  • Department of Veterans Affairs

Further Reading

  1. Hertz, NR, et al. “Coronary artery disease in peripheral vascular patients. A classification of 1000 coronary angiograms and results of surgical management.” Ann Surg. 1984 Feb;199(2): 223-233.
  2. Ruby ST, et al. “Coronary artery disease in patients requiring abdominal aortic aneurysm repair. Selective use of a combined operation.” Ann Surg. 1985 Jun;201(6): 758-764.
  3. Sprung J, et al. “Analysis of risk factors for myocardial infarction and cardiac mortality after major vascular surgery.” Anesthesiology. 2000 Jul;93(1): 129-140.
  4. Jamieson WR, et al. “Influence of ischemic heart disease on early and late mortality after surgery for peripheral occlusive vascular disease.” Circulation. 1982 Aug;66(2 Pt 2):l92-7
  5. Poldermans D, et al. "A clinical randomized trial to evaluate the safety of a noninvasive approach in high-risk patients undergoing major vascular surgery: the DECREASE-V Pilot Study." JACC. 2007;49(17):1763-1769.
  6. Monaco M, et al. “Systematic strategy of prophylactic coronary angiography improves long-term outcome after major vascular surgery in medium- to high-risk patients: a prospective, randomized study.” JACC. 2009 Sep 8;54(11)989-996
  7. JACC Editors. "Notice of concern." JACC. 2012;60(25):2696-2697.
  8. Fleisher LA, et al. “2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.” Circulation. 2014 Dec 9;130(24)e278-333
  9. Fleisher LA, et al. “2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.” Circulation. 2014 Dec 9;130(24)e278-333