The Coronary Angiogram and Its Seminal Contributions to Cardiovascular Medicine Over Five Decades

The selective hand injection of contrast media into the right coronary artery of a middle-aged male by Doctor F. Mason Sones on October 30, 1958 introduced a new era in Cardiovascular Medicine. It is the purpose of this presentation to portray the pivotal role the coronary angiogram has played in creating some of the epochal events and discoveries that have characterized the march of progress in the field of cardiology over the past five decades. As the first reliable in vivo marker for the presence of obstructing coronary lesions, the coronary angiogram importantly led to our first studies of the natural history of patients with CAD. The motion studies afforded by cineangiography also permitted dynamic visualization of the contracting ventricle which led to the concept of regional wall motion abnormalities being characteristic of CAD and provided some of our earliest understanding of left ventricular dysfunction. The coronary angiogram also provided the stimulus for the development of aorto-coronary bypass surgery that was introduced by Dr. Rene Favaloro in May 1967. Subsequently, Dr. Andreas Gruntzig astounded the cardiology world by reporting his new percutaneous method of achieving revascularization (PTCA). The coronary angiogram provided the road map necessary for the successful deployment and application of this balloon technology that was soon to rival CABG surgery. The thrombolytic era was heralded in July 1979 when Dr. Peter Rentrop documented the successful reperfusion of a coronary artery in a 57-year old man by first recanalizing the occluding thrombus with a guidewire and then infusing the proteolytic enzyme, streptokinase directly into the artery. Within a year, DeWood made the angiographic observation that spontaneous regression of the totally occluding thrombus occurred among patients undergoing coronary arteriography within the first 24 hours of the onset of symptoms of an acute myocardial infarction. This led to the earliest studies on clot lysis by fibrinolytic agents and also paved the way for the balloon catheter to be used as a mechanical means of achieving coronary reperfusion in the acute setting. In the 1980s it was realized that vigorous lipid lowering with statin drugs did little to effect regression of the established atherosclerotic lesion but it did result in a dramatic decrease in subsequent clinical cardiovascular events. Similar observations were made by Little and others that acute coronary occlusion resulted more often from young, non-obstructing atheromatous lesions than it did from high grade obstructive lesions. This incriminated rupture of the soft, lipid rich atheromatous plaque as the most common mechanism leading to acute MI. In the closing decade of the past century, estimates of coronary blood flow using TIMI flow grades and TIMI frame rates led to the central unifying concept that the early restoration of normal flow (TIMI grade 3) was linearly related to survival after reperfusion therapy whether it be achieved pharmacologically or mechanically. The coronary angiogram was also integral in establishing antiplatelet therapy as the preferred pharmacotherapeutic agents to be used in association with stent deployment compared to coumarin drugs in preventing stent thrombosis. Although the coronary catheter is now used to deliver newer intracoronary devices such as intravascular ultrasound, velocity probes, gene probes and eluting catheters, it has served as the one indispensable form of coronary imaging for five successive decades. As such it has provided far more than is implied by the term "lumenology" and can rightly be called the lumen de lumine, the light of lights, for cardiovascular medicine.