Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease

BACKGROUND:

Congestive heart failure afflicts approximately five million Americans and is the leading cause of hospitalization in Americans over the age of 65. Most cases of congestive heart failure are due to CAD. Surprisingly little is known about the relative benefits of medical versus surgical therapy for patients with obstructive coronary disease and congestive heart failure. Randomized studies of medical therapy versus bypass surgery for obstructive coronary disease were conducted in the 1970s and did not include the systematic use of aspirin, arterial conduits, or lipid-lowering medications. In addition, patients with ejection fractions below 35% were specifically excluded from the three large randomized studies of medical therapy versus bypass surgery. While observational data from the 1970s and early 1980s suggest a survival advantage associated with bypass surgery in patients with low ejection fraction and congestive heart failure, biases favoring the referral of the fittest of such patients for bypass surgery may have confounded these comparisons. In addition, medical therapy for congestive heart failure has improved dramatically over the past two decades. Thus, the choice of medical therapy versus bypass surgery for patients with congestive heart failure and obstructive coronary disease is usually decided by guesswork. This study is designed to provide a solid answer.

PURPOSE:

STICH is a multicenter, international, randomized trial that addresses two specific primary hypotheses in patients with clinical heart failure (HF) and left ventricular (LV) dysfunction who have coronary artery disease amenable to surgical revascularization.

The first hypothesis is that restoration of blood flow by means of coronary revascularization recovers chronic LV dysfunction and improves survival, as compared to intensive medical therapy alone. The second hypothesis is that surgical ventricular restoration (SVR) to a more normal LV size improves survival free of subsequent hospitalization for cardiac cause compared to CABG alone.

Patients eligible for either medical therapy or CABG, but not eligible for the SVR procedure (Stratum A), will be randomized in equal proportions to medical therapy alone versus CABG plus medical therapy. Patients eligible for all three therapies (Stratum B) will be randomized in equal proportions to medical therapy alone, CABG plus medical therapy, and CABG plus SVR plus medical therapy. Patients whose severity of angina or CAD makes them inappropriate for medical therapy alone (Stratum C) will be randomized in equal proportions to CABG plus medical therapy versus CABG plus SVR plus medical therapy.

The overall target was to recruit 1200 patients into Hypothesis One and 1,000 patients into Hypothesis Two. Secondary endpoints include the role of myocardial viability, morbidity, economics, and quality of life. Core laboratories for quality of life/economics, cardiac magnetic resonance (CMR), echocardiography (ECHO), neurohormonal/cytokine/genetic (NCG), and radionuclide (RN) studies ensure consistent testing practices and standardization of data necessary to identify eligible patients and to address specific questions related to the stated hypotheses.

IMPORTANCE OF RESEARCH:

The most common cause of HF is no longer hypertension or valvular heart disease as it was in previous decades, but rather CAD. HF is a common worldwide disease and CAD is a frequent cause of HF initiation and progression. HF is responsible for approximately 1 million hospitalizations and 300,000 fatalities annually. The prevalence of HF is increasing, largely due to enhanced survival following acute myocardial infarction and other manifestations of CAD. No randomized trial has ever compared directly the long-term benefits of surgical, medical, or combined surgical and medical treatment of patients with ischemic HF. The STICH trial is the first trial to compare the long term benefits of surgical and medical treatment in patients with ischemic HF. Although modern medical therapy for HF modestly improves quality of life, a more aggressive approach with the surgical therapies being studied in the STICH trial may produce even greater improvements. The common clinical practice of not offering CABG to patients with LV dysfunction in regions found to be nonviable on noninvasive studies is not evidence-based. Since only those patients for whom intensive medical therapy is the only reasonable therapeutic alternative are excluded from this study, the results of the STICH trial should be applicable to most patients with CAD, HF, and systolic LV dysfunction. The results of the STICH trial will also establish whether measurements of neurohormonal and cytokine levels and genetic profiling are useful for directing patient management decisions, for monitoring the effectiveness of therapy, and for refining the optimal approach for selecting the treatment strategy most likely to be effective for the many of these patients.