Читать книгу Practical Cardiovascular Medicine - Elias B. Hanna - Страница 192

When should stress testing be repeated in patients with prior negative studies who present with chest pain? Stress tests have “warranty periods” during which the risk of cardiovascular events is low (<1% per year) and during which there is no need to perform a coronary angiogram unless the patient has objective evidence of new CAD, such as ACS with positive cardiac markers or new, severe ischemia on the ECG.

This “warranty period” of a stress test varies according to the context, and is generally 1-2 years, less so for pharmacological testing, older age (>70-80), CAD history, or uncontrolled risk factors.²⁶

When a coronary angiogram shows normal coronary arteries or minimal disease, the risk of coronary events is low for 5 years, and unless there is evidence of MI, the angiogram is not usually repeated within the next 5 years. As per the CASS registry, the 7-year survival is 96% for patients with normal EF and normal coronaries and 92% for patients with mild coronary disease <50% (much better prognosis than obstructive CAD).²⁷

How about patients who had a coronary angiogram showing single- or multivessel moderate disease (30–70%), or showing severe disease (>70%) in a small branch where PCI is not beneficial? If they present with recurrent or persistent chest pain a few months or 1–2 years later, the coronary angiogram may not need to be repeated unless there is an ischemic ST abnormality, a positive troponin, or a dramatic change in the severity of a typical, exertional angina. Also, the true functional significance of moderate stenoses (50–70%) is worth assessing with stress imaging or FFR.

Patients with moderate stenoses that are insignificant by FFR have a very low risk of MI from each individual stenosis, yet the summation risk of MI from all nonsignificant lesions is not negligible, ~1.5% per year (FAME 2 trial).²⁸

These “warranty periods” are used for guidance; ultimately, decisions are based on clinical judgment.