At its height, the popularity of surgical coronary revascularization spurred improvement in catheter-based technology—first for imaging quality and later for attempted therapy. In 1974, Andreas Gruentzig completed development of the double-lumen balloon catheter that was miniaturized for use in coronary arteries. Soon afterward, techniques for percutaneous transluminal coronary angioplasty (PTCA) expanded as technical breakthroughs were applied to subselective catheters, devices, guidewires, balloon materials, and lastly, coronary stents. Presently trial evidence attests that percutaneous therapy is useful as a treatment in patients with unacceptably controlled angina whose anatomy does not imply a survival benefit from revascularization or for patients with uncontrollable, unstable symptoms. However, surgical and percutaneous revascularization cannot be considered equivalent.1
In the early balloon angioplasty era, several technical limitations restricted percutaneous techniques to low-risk patients with proximal, discrete coronary artery stenoses, and procedural outcomes lacked predictability. As advances in tools and techniques were developed, higher-risk patients became candidates for percutaneous therapy. Over time, several principles for safety and success were recognized (Table 20-1).
Table 20-1 Principles of Percutaneous Coronary Intervention ||Download (.pdf)
Table 20-1 Principles of Percutaneous Coronary Intervention
|1. The patient's outcome is a function of age and comorbidity.|
|2. The procedure's outcome is a function of anatomy and proper planning (ie, sequence and equipment choices, such as guidewires and device).|
3. Proximal and distal control of the treated vessel must be maintained.
a. Choose proper guide catheter support.
b. Maintain distal wire position.
c. Keep the guide, device, and distal wire tip visible during any movement of any device.
4. Needs and limits to treatment options such as devices, adjuvant medical therapy, contrast use, and circulatory support are determined by
a. Vascular access
b. Clinical setting (eg, stable angina or acute myocardial infarction)
c. Ventricular function
d. Comorbidities: diabetes mellitus, renal insufficiency
5. The following factors can lead to failure:
a. Incomplete understanding of the three-dimensional anatomy of the course to be taken and lesion to be treated
b. Unrealistic interpretation of
i. The capacity of available techniques to achieve success
ii. The allowance of specific anatomy to accept percutaneous manipulation
iii. Ignorance or inattention to technique in subselective device movement
c. Inattention to anticoagulation
d. Inattention to catheter hygiene (minimizing blood and contrast stagnation within the guiding catheter or other devices)
Guiding catheters differ from diagnostic catheters in that a wire-braid supports a thin catheter wall, allowing for a larger central lumen and providing enough rigidity to support the advance of subselective catheters to the distal regions of the coronary bed. The anatomy of the ascending aorta and the origin of the treated coronary artery determine the shape of the guiding catheter that will provide the most secure positioning (Fig. 20-1). The choice of guiding catheter often is the deciding factor for success ...