The development and evolution of cardiac catheterization into therapeutic percutaneous coronary intervention (PCI) has been the result of the work of a long list of pioneers and of their forward thinking, persistence, and tolerance to risk taking. In 1964 Dotter and Judkins reported the initial results of dilatation of peripheral vessels’ stenosis using tapered, radiopaque, Teflon dilating catheters slipped over a guidewire (“the Dotter effect”) (FIGURES 18.1 and 18.2).¹ Around the same time, Andreas Gruentzig in Switzerland had been developing the concept of balloon dilatation of vessels’ stenosis. His early balloons were made of PVC and connected to a single lumen catheter (FIGURE 18.3).² After several attempts trying to convince catheter companies to build a double lumen catheter, Gruentzig was finally able to develop a double lumen catheter with the help of Mr Schmidt.² The balloon was used in an iliac artery on January 23, 1975 and then it was used on September 16, 1977 to perform the first percutaneous transluminal coronary angioplasty (PTCA).³,⁴ As shown in FIGURES 18.4 and 18.5, the lesion was in the proximal left anterior descending artery before the bifurcation into a diagonal artery. Two balloon inflations were performed. After the second balloon inflation, the residual pressure gradient across the stenosis resolved. As Gruentzig later stated, “his dreams had come true.”² The following years were characterized by a tremendous effort focused on the development of new techniques and the introduction of new technology. The introduction of the steerable guide wire and of low-profile balloons (FIGURE 18.6) allowed tackling lesions in more distal portions of coronary arteries. New applications of coronary angioplasty beyond stable angina, including the management of patients with acute coronary syndromes and ST segment elevation myocardial infarction, were developed. The introduction in the 1990s of coronary stenting further improved the safety of PCI and long-term outcomes,⁵,⁶,⁷,⁸ while restenosis was formally “conquered” in 2000 with the introduction of drug-eluting stents. It is unknown whether Gruentzig, at the time of his humble first report, was predicting the revolution that would ensue and the exponential growth in PCI (FIGURE 18.7).

The mechanism of balloon angioplasty is based on a controlled balloon injury to the arterial wall leading to plaque disruption and enhancement of blood flow (FIGURES 18.8 and 18.9). Ultrasound imaging has shown that the improvement in lumen diameter following PTCA is due to a combination of vessel stretch and local dissection⁹ (FIGURE 18.9). The major limitations of balloon angioplasty include abrupt closure secondary to an uncontrolled dissection and the development of restenosis. Elastic recoil, chronic restrictive remodeling, and intimal hyperplasia can lead to progressive renarrowing of the vessel following PTCA (FIGURES 18.8, 18.9 and 18.10). By providing a scaffolding system to the artery, coronary stenting has addressed most of the intrinsic limitations of PTCA. Our readers are referred to Chapter 20 for a review of coronary stenting. In this chapter, we will review basic concepts of PTCA, as well as some of the pivotal clinical trials evaluating the role of PTCA in the management of patients with coronary artery disease.

Adequate guide catheter support is a critical component of successful PCIs. The guiding catheter design has evolved with a progressive reduction in outer diameter, an increase in inner lumen without a reduction in catheter stiffness and support, and by the development of atraumatic tips (FIGURE 18.11). Critical characteristics of guide catheters include ease of handling, backup support, ability to advance devices through the inner lumen, and atraumatic engagement (Table 18.1). In addition, multiple shapes have become available to allow intubation of coronary arteries with different anatomy and takeoff via the transfemoral, transradial, or brachial approach (FIGURES 18.12, 18.13, 18.14, 18.15, 18.16, 18.17, 18.18, 18.19, 18.20, 18.21, 18.22 and 18.23). An overview of catheters available for transradial approach is provided in Chapter 4. Different shapes are characterized by a primary curve, which is located at the level of the tip of the catheter, and by secondary and occasionally tertiary curves (FIGURE 18.24).

Coaxial alignment of the guide catheter with the ostium of the coronary artery is critical to minimize the risk of guide catheter—induced proximal dissection and to optimize guide catheter support and advancement of devices (FIGURES 18.25 and 18.26). Guide catheters can be divided into 2 broad categories: passive support and active support. Passive support relies on the property of the catheter shaft and tip to maintain position within the ostium of the coronary artery. They are rarely deep seated and they require minimal manipulation. Active support relies on manipulation of the guide catheter, deep seating when needed through rotation of the catheter and it uses the aortic root with different guide catheter curves to provide backup support. Table 18.2 lists factors to be considered in the selection of guide catheters.