2.8. Assessment of health-related quality of life using Seattle Angina Questionnaire (SAQ)

SAQ was given to patients at the time of their CMR scans (baseline and follow-up). It is a widely used questionnaire to assess health outcome measures in patients with coronary artery disease. It consists of a 9-item scale of physical limitations (how daily activities are limited by angina), 1-item scale for angina stability (assesses change in frequency of angina at patient most strenuous level of activity), 2-item scale for angina frequency (frequency of symptoms and use of medications), a 3-item for perception scale (effect of angina on quality of life), and a 4-item treatment satisfaction scale quantifies patients’ satisfaction with their current treatment. All items use 5 point descriptive scales and scores are calculated summing all the single scores within each group and transforming them to a scale of 0–100, where 0 is the worst and 100 is the best [19,20].

Short term outcome: (6 months follow up)

It was performed 6 months after successful CTO-PCI.

Assessment of HRQOL: through SAQ.

CMR follow-up study to assess LV end systolic volume (ESV), LV end diastolic volume (EDV), LVEF and WMSI to detect functional recovery of systolic function and reverse myocardial remodeling. Good LV functional recovery was defined as 5% increase in ejection fraction on follow up study. This definition is concordant with recent large meta-analysis [18].