A kerfuffle ensued recently when an oncologist and expert on evidence based medicine took the field of cardiology to task over the evidence for placement of the ubiquitous coronary stent. What started with a lengthy article in Propublica that included coronary stenting for stable coronary disease as a prime example of a procedure done without evidence to back it up turned into this fiery twitter exchange between Drs. Kirtane (cardiology) and Prasad (oncology).
The crux of the debate revolves around placement of coronary stents in patients with stable coronary artery disease. Stable coronary artery disease refers to narrowing of the arteries by a build of plaque that has occurred slowly over time. Unstable coronary artery disease refers to eruptions that occur within the coronary vessel when a plaque ruptures, quickly leading a patent vessel to become completely occluded or nearly occluded. Unstable coronary artery disease, otherwise referred to as an acute coronary syndrome is regarded as an emergency that requires urgent intervention by skilled operators (interventional cardiologists) who must race against time to abort a process that if left unchecked may lead to death or severe damage of the heart muscle.
Figure 1. Stable angina/Acute Coronary syndromes
Stable coronary artery disease on the other hand is not considered an emergency, but can result in patients being symptomatic because of diminished blood flow through the culprit artery. Angina pectoris is the descriptor one uses to describe chest pain that relates to a mismatch between the blood flow the heart muscle needs and what it receives. It is almost always the case that angina in stable coronary disease is triggered by activities such as physical or emotional stress that require more blood flow than the narrowed artery can supply.