VASCULAR SURGICAL REPAIR

Vascular Surgical Repair: Stenting or Graphing

Vascular Surgical Repair: Stenting or Graphing

In Meredith Willson's “The Music Man,” sleepy River City, Iowa, comes under musical assault from a smooth and self-assured confidence man, Professor Harold Hill. He declares that restless youth (who are not so restless) are in moral peril but may be saved through an effortless acquisition of musical skill requiring only the purchase of uniforms and instruments, and the use of the “think” method. Of course, the think method is a sham promulgated to convince these offbeat Iowans to enrich the good professor and gain little in return. Fortunately, the sham and its purveyor are very entertaining.

You may ask how this pertains to revascularization therapy. The common ground lies in the glee with which our surgical colleagues point to the application and failures of balloon angioplasty, which offers a comparison in which cardiologists are Professor Hill and percutaneous transluminal coronary angioplasty (PTCA) is the “think” method. In this scenario, the cardiologist identifies every coronary lesion as a source of peril. Salvation is offered, with less musical distraction but equal reward, in the form of morbidity-free angioplasty, and patients are diverted from a more effective means of revascularization.

There is a kernel of truth in this argument. Not every lesion requires revascularization. Angioplasty is not without risk and frequently fails within the first 6 months after the procedure. In populations whose survival is unlikely to be affected by any revascularization procedure, PTCA compares favorably to coronary bypass surgery, albeit with a substantially greater need for more procedures. Worse still, in the high-risk diabetic subpopulation with multivessel coronary stenosis, a 1st choice of PTCA carries a heavy toll in both the need for repeat procedures and, more importantly, survival. However, I hope to convince you that with the recent advances in stent-assisted angioplasty (recently acquiring the abbreviation PCI, for percutaneous coronary intervention) proper application now offers a very good alternative to surgery. But, as Professor Hill was admonished as he disembarked in River City to begin his confidence game, “you've gotta know the territory.”

The introduction of coronary artery bypass grafting (CABG) was an enormous advance in the treatment of coronary artery disease. Successful bypass reduced angina and improved exercise capacity. When studied in randomized trials of early surgical referral CABG proved effective in reducing mortality. However, 3 central principles of that survival impact quickly became apparent: 1) the amount of potential survival benefit was roughly proportional to the patient's risk of death from the next coronary event, whether estimated using clinical, angiographic, or physiological variables; 2) revascularization was not a treatment for atherosclerosis, but a means of reducing the impact of later disease progression; and 3) benefit lasted only as long as the grafts remained patent.

When we examine the outcome of the VA Cooperative trial,4-6 these principles can be seen clearly. Early on, procedural risk obscured the impact of successful revascularization; but by 5 years, improved survival in surgically treated patients was apparent. This apparent difference was statistically verified only in patients ...