PCI of LAD Improved Inferoseptal Perfusion in RCA CTO Patient

In the anterior/apical myocardium, the perfusion was normal (2.9 ml/g/min). Global stress-flow was 2.4 ml/g/min. The patient was referred to invasive coronary angiography (ICA) showing a 70% stenosis of the proximal LAD, 90% stenosis of the LAD/D1 bifurcation, and CTO of RCA with retrograde filling from the LAD through the septals and ipsilateral filling from marginal branches from the RCA. Corresponding to the LAD lesion, fractional flow reserve (FFR) was 0.77, coronary flow reserve 2.4, and index of microcirculatory resistance 10. As the patient was part of a research protocol (the Dan-NICAD II trial 3) ), the invasive cardiologist was blinded to the 82 RbPET re-sult, and the revascularization strategy was based solely on the invasive information. Hence, the LAD and LAD/D1 lesions were treated with percutaneous coronary intervention (PCI) using A patient with chest pain and inferoseptal ischemia at Rubidium-82 Positron Emission Tomography ( 82 RbPET) was revascularized in a stenosis in the LAD/D1 bifurcation, while a CTO RCA was left untreated. One-year follow-up with Seattle Angina Questionnaire and repeat 82 RbPET revealed symptom relief and improved inferoseptal perfusion likely through LAD collateralization.