March 30th, 2011
ACC Preview: A STICH in Time
Eric Velazquez is the principal investigator of the STICH (Surgical Treatment for Ischemic Heart Failure) trial. He will present the main results of the trial at the Late’Breaking Clinical Trials II session on Monday morning. Velazquez relates the origins of STICH more than a decade ago and discusses some of the fascinating challenges of completing such a unique trial.
Next week, I will present results of the Surgical Revascularization Hypothesis of the Surgical Treatment for Ischemic Heart Failure, or STICH, trial at the ACC. The trial’s origins go back more than a decade and emanated from three related clinical observations:
1. Heart failure patients were commonly referred for noninvasive testing to determine whether they should be considered candidates for CABG. For many physicians, those test results drove decision making
2. Although, overall, CABG rates were flat, or at some centers even decreasing, the proportion of patients with heart failure and left ventricular dysfunction who were referred for CABG was rising.
3. The Coronary Artery Surgery Study (CASS) and other randomized clinical trials that informed the formulation of CABG guidelines excluded heart failure patients. These studies were performed in the 1970s, before the initiation of contemporary evidence-based medical therapy, leaving substantial clinical uncertainty regarding the incremental value of CABG for such patients.
Medical therapy and CABG have improved dramatically since then for heart failure patients. For instance, aspirin was used in less than a quarter of CASS patients, beta blockers were contraindicated for heart failure, and ACE inhibitors didn’t even exist. In surgery, the internal mammary artery was used in only 11% of cases.
We’ve also changed our interpretation of earlier results. We now believe that CABG benefits those with the highest risk, and we don’t remember that in the CASS trial and in the CASS registry reports, the presence of HF symptoms with no angina suggested no benefit from CABG. Clinical practice has changed: PCI is used preferentially in lower-risk coronary cohorts while CABG is increasingly used in people with low EFs. In the New York database, for instance, upwards of 40% of the population who received CABG had an EF that would have excluded them from previous randomized trials of CABG versus medical therapy.
Beginning in 2000, in response to these developments, we submitted an investigator-initiated request to the NIH to evaluate the role of surgical revascularization in patients with heart failure. We were also interested in, and have previously reported on, the effect of adding SVR to CABG. We enrolled patients whose physicians held in genuine equipoise the question of whether continuing medical therapy or CABG was in that patient’s best long-term interest. This enrollment strategy was challenging, because many patients, cardiologists, and surgeons had preformed ideas on the issue and were hesitant to leave a decision regarding surgery to randomized assignment, but that’s what was needed to clearly answer the question.
With the help of 1212 patients enrolled by 99 clinical investigative teams in 22 countries, the STICH trial went forward. I remember presenting cases at some of the best surgical investigative sites in the world, and watching the debate unfold regarding the best strategy for a particular patient. It was not unusual for several physicians to present completely different perspectives on how the patients should be evaluated and treated. These debates brought home to me that the answers were critically needed, despite any difficulties. There is tremendous heterogeneity in how heart failure patients with similar baseline features are evaluated and treated by excellent, well-intentioned physicians who are hampered by the lack of adequate data and evidence.
We achieved excellent follow-up and are excited to present these results early next week at ACC. Following my presentation of the main results of the trial, Bob Bonow will present the results of an important substudy of patients who had SPECT or dobutamine.
For more of our ACC.11 coverage of late-breaking clinical trials, interviews with the authors of the most important research, and blogs from our fellows on the most interesting presentations at the meeting, check out our Coverage Roundup.