Contemporary Methods to Evaluate Obstructive CAD
A 78-year-old male patient with a medical history of hypertension, hyperlipidemia, coronary artery disease (CAD), and smoking presents for the evaluation of chest pain. The patient reports episodic chest pain that is retrosternal with left arm radiation for the last 3 months. The pain is largely related to exertion; however, he notes at times it occurs at rest as well without clear triggers. Each episode of chest pain lasts roughly 20 minutes before resolution. He had an inferior ST-segment elevation myocardial infarction 5 years before, and the coronary angiogram then showed total right coronary artery (RCA) occlusion, which was revascularized with a drug-eluting stent. The remainder of the angiogram at that time demonstrated nonobstructive plaque in the other coronary vessels. His medications include aspirin 81 mg daily, metoprolol 25 mg daily, losartan 50 mg daily, isosorbide mononitrate 60 mg daily, and atorvastatin 80 mg daily.
On examination, his heart rate is 68 bpm and blood pressure is 128/72. Cardiovascular examination discloses normal first and second heart sounds with no murmurs. The remainder of the examination is unremarkable. An electrocardiogram shows normal sinus rhythm with Q waves in the inferior leads, unchanged when compared with prior. He is referred for cardiac catheterization that shows a moderately obstructive focal lesion in the proximal left circumflex artery (LCx) that is graded as 60% by visual approximation, mild-moderate nonobstructive lesion in the mid LCx, unchanged mild nonobstructive disease in the left anterior descending artery (LAD), and a patent RCA stent with minimal restenosis. A hemodynamic assessment with instantaneous wave-free ratio (iFR) is performed at the proximal LCx site, which demonstrates a ratio of 0.81, and a drug-eluting stent is successfully placed with Thrombolysis in Myocardial Infarction 3 post-percutaneous coronary intervention (PCI) angiographic flow.
Which of the following testing strategies may provide additional prognostic information regarding symptoms and major adverse cardiovascular outcomes?