Appropriateness for Revascularization in Stable Angina

July 22, 2010


Ramin Shayegan Hastings MD, Jonathan Willner MD, and Steven Sedlis MD

Introduction to Cases:

During the past several weeks, we have posted a series of cases addressing the appropriate treatment for patients with stable coronary artery disease. We have focused on indications for revascularization in stable angina. In all of the cases, the patients have been at high enough risk that stress tests and coronary angiography are performed.

There has been recent data and recommendations on the appropriate indications for revascularization in stable angina. These recommendations are based on clinical symptoms, non-invasive imaging, and catheterization findings. After reading through these cases, we hope you have a better understanding of what the appropriate indications are for revascularization, and the evidence behind them.

Review Case #1

Review Case #2

Review Case #3

Case #4

The patient from Case # 1 (see previous post) comes back to the clinic for a follow up visit.

In review, he is a 54-year-old male with hypertension and tobacco use who presented with anginal chest pain 1 year ago. He was found to have low-risk findings on stress testing, and a cardiac catheterization revealed 2 vessel disease (not affecting the proximal left anterior descending artery (LAD)). He was treated with medical therapy including blood pressure control, treatment of hyperlipidemia with a goal LDL of 100, long-acting nitrates, aspirin, tobacco cessation, and an exercise program.

However, the patient states that his angina has continued despite treatment. Over the past 3 months it has worsened, and now he is not able to continue his work as a plumber because of continuing pain. After walking only short distances, about 2 blocks or one flight of stairs, he develops chest pain. He still has not had any pain at rest, and physical exam is unchanged from previous. ECG is also unchanged from previous.

What is the appropriate next step in treatment?

A. No change in treatment

B. Increase the dose of long-acting nitrates

C. Repeat stress test with catheterization only if new abnormalities are noted

D. Repeat catheterization with subsequent revascularization only if new lesions are noted

E. Repeat catheterization with revascularization of lesions that correlate with areas of ischemia on previous stress or echocardiography

Answer: E

In this case, we have the same patient from the previous post who had low-risk findings on non-invasive testing, CCS class II anginal symptoms off medication, and 2 vessel disease on catheterization. See the previous post about why medical therapy was an appropriate initial treatment strategy for this patient. His symptoms have worsened despite medical therapy.

His symptoms can now be classified as CCS class III angina (1). In addition, his symptoms are now affecting his daily life as he is not able to work. He was started on medical therapy, however we would not consider it optimal medical therapy. Optimal medical therapy would include two or more anti-anginals (beta-blocker, calcium channel blocker, and/or angiotensin converting enzyme (ACE) inhibitor), along with lipid control, exercise program, smoking cessation, and blood pressure control. While recent studies have found there is no mortality benefit with revascularization for the majority of patients with similar findings as this patient (see previous posts), several studies have shown there is a reduction in symptoms of patients undergoing revascularization. Early randomized studies showed that patients often had significant improvements in anginal symptoms after revascularization utilizing coronary artery bypass grafting (CABG). In the Veterans Administration Cooperative Study 38.5% of patients who underwent revascularization were angina free at one year compared with 8.8% in medical therapy (2). However, this improvement was no longer apparent 10 years after randomization (3). Similar findings were noted in the Coronary Artery Surgery Study (CASS), as patients randomized to revascularization had significant improvements in chest pain through 5 years after randomization (63% chest pain free with CABG vs. 38% with medical therapy after 5 years) (4). These studies were before the advent of some newer medical therapies known to improve coronary artery disease.

Studies comparing revascularization with Percutaneous Transluminal Coronary Angioplasty (PTCA, balloon angioplasty) to medical therapy in patients with stable angina painted a similar picture. The Second Randomized Intervention Treatment of Angina (RITA-2) Trial randomized 1,018 patients with stable angina to PTCA or medical therapy. Although they found no mortality benefit with PTCA (see previous post), patients treated with revascularization had a significant improvement in anginal symptoms. 3 months after randomization 19.4% of the PTCA group had angina class II or worse compared to 35.9% of the medical therapy group. This difference remained for five years, however after eight years no significant improvement in symptoms were noted with the group treated with PTCA (4). Newer data shows the improvement in symptoms with revascularization may not be as great as once though. The most applicable study for this patient is the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial which randomized 2,287 patients with stable angina to percutaneous coronary intervention (PCI) with aggressive medical therapy or aggressive medical therapy alone (5). There was no difference in the primary outcome of death and myocardial infarction (MI, see previous post). Subsequent analyses found patients randomized to PCI had an improvement in symptoms at 1 year, although this was no longer present at 3 years (At 1 year 57% were free of angina with PCI vs. 50% free of angina in medical therapy; after 3 years that changed to 59% and 56% respectively).

Based on these data, the American College of Cardiology (ACC) and American Heart Association (AHA) recommend PCI or CABG “for patients who have not been successfully treated with medical therapy and can undergo revascularization with acceptable risk,” as a class IB recommendation (6). Medical treatment has failed this patient, as his symptoms have continued to worsen despite adequate medical treatment. In addition, he is having disabling angina and the appropriateness criteria for revascularization released by the ACC rated revascularization appropriate in patients with CCS class III or IV angina with almost any disease noted on angiography (except 1-2 vessel disease off treatment with low/intermediate risk findings on stress) (7). Revascularization with PCI or CABG would be appropriate in this patient, even if no further disease is noted on cardiac angiography. In addition, as stated above, an increase in his medical management with beta-blockers, calcium channel blockers, and ACEI is indicated as well.

As you can see, we have laid out two different indications for revascularization in patients with stable angina. The first is to improve survival, as may be the case in patients with high-risk findings on angiography or non-invasive testing (see previous post). The other is for symptom control in patients who have disabling angina or when symptoms are not adequately controlled with medical therapy alone.

 

References

1. Campeau L. The Canadian Cardiovascular Society grading of angina pectoris revisited 30 years later. Can J Cardiol2002 Apr;18(4):371-9. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11992130

2. Peduzzi P, Hultgren HN. Effect of medical vs surgical treatment on symptoms in stable angina pectoris. The Veterans Administration Cooperative Study of surgery for coronary arterial occlusive disease. Circulation1979 Oct;60(4):888-900. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=113129

3. Eighteen-year follow-up in the Veterans Affairs Cooperative Study of Coronary Artery Bypass Surgery for stable angina. The VA Coronary Artery Bypass Surgery Cooperative Study Group. Circulation1992 Jul;86(1):121-30. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=1617765

4. Rogers WJ, Coggin CJ, Gersh BJ, Fisher LD, Myers WO, Oberman A, Sheffield LT. Ten-year follow-up of quality of life in patients randomized to receive medical therapy or coronary artery bypass graft surgery. The Coronary Artery Surgery Study (CASS). Circulation1990 Nov;82(5):1647-58. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=1977531

5. Boden WE, O’Rourke RA, Teo KK, Hartigan PM, Maron DJ, Kostuk WJ, Knudtson M, Dada M, Casperson P, Harris CL, Chaitman BR, Shaw L, Gosselin G, Nawaz S, Title LM, Gau G, Blaustein AS, Booth DC, Bates ER, Spertus JA, Berman DS, Mancini GB, Weintraub WS. Optimal medical therapy with or without PCI for stable coronary disease. N Engl J Med2007 Apr 12;356(15):1503-16. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17387127

6. Gibbons RJ, Chatterjee K, Daley J, Douglas JS, Fihn SD, Gardin JM, Grunwald MA, Levy D, Lytle BW, O’Rourke RA, Schafer WP, Williams SV. ACC/AHA/ACP-ASIM guidelines for the management of patients with chronic stable angina: executive summary and recommendations. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients with Chronic Stable Angina). Circulation1999 Jun 1;99(21):2829-48. http://circ.ahajournals.org/cgi/content/full/99/21/2829

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10351980

7. Patel MR, Dehmer GJ, Hirshfeld JW, Smith PK, Spertus JA. ACCF/SCAI/STS/AATS/AHA/ASNC 2009 Appropriateness Criteria for Coronary Revascularization: A Report of the American College of Cardiology Foundation Appropriateness Criteria Task Force, Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, American Association for Thoracic Surgery, American Heart Association, and the American Society of Nuclear Cardiology: Endorsed by the American Society of Echocardiography, the Heart Failure Society of America, and the Society of Cardiovascular Computed Tomography. Circulation2009 Mar 10;119(9):1330-52. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19131581