Stable Angina, Unstable Angina
Conditions
Keywords
Bifurcation, Side branch, Ischemia, Myocardium, Revascularization
Brief summary
This study was performed to investigate the anatomical attributes that determine myocardial territory of diagonal branches and to develop a prediction model for clinically relevant branches using myocardial perfusion imaging (MPI) and coronary CT angiography (CCTA).
Detailed description
Bifurcation lesion is one of the most challenging lesion subsets in the field of percutaneous coronary intervention (PCI). Despite the recent advances in PCI techniques and stent technology, most randomized studies failed to prove the superiority of systematic 2 stenting strategy compared with provisional side branch intervention strategy. A certain amount of ischemic burden is required to achieve the benefit of revascularization over medical treatment. Compared with major epicardial vessels, side branches are smaller, more variable in anatomy, supplying less myocardium and less clinically relevant. Therefore, it is important to assess the myocardial mass at risk of side branches to determine the appropriate treatment strategy for bifurcation lesions. However, how to define the clinically relevant side branches which can be associated with the benefit of revascularization in a cardiac catheterization laboratory is not well-known. The investigators performed this study to investigate the anatomical attributes that determine ischemic burden and myocardial territory of diagonal branches and to develop a prediction model for a clinically relevant diagonal branch using myocardial perfusion imaging (MPI) and coronary CT angiography (CCTA).
Interventions
None listed
Sponsors
Study design
Eligibility
Inclusion criteria
* Patients with severe jailed diagonal branch disease with available MPI in 3 months (MPI arm) * Patients who had available FMM value of diagonal branches from a previous multicenter prospective CCTA registry (CCTA arm)
Exclusion criteria
* Patients with \>50% stenosis at left anterior descending coronary artery (LAD) or left circumflex artery (LCx), regional wall motion abnormality at LAD territory (MPI arm) * Patients with diffuse diagonal branch disease (CCTA arm)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Accuracy of prediction model | through study completion, an average of 1year | Prediction model using anatomical attributes to define clinical relevance of diagonal branches will be developed. |
| Positive predictive value of prediction model | through study completion, an average of 1year | Prediction model using anatomical attributes to define clinical relevance of diagonal branches will be developed. |
| Area under the curve of prediction model | through study completion, an average of 1year | Prediction model using anatomical attributes to define clinical relevance of diagonal branches will be developed. |
| Angiographic attributes for diagonal branches | through study completion, an average of 1year | Angiographic attributes for diagonal branches were visually defined as follows : 1. Size was a binary attribute of vessel diameter ≥ 2.5mm or \< 2.5mm. 2. Number was counted as one, two, and 3 or more diagonal branches. 3. Dominancy in patients with 2 diagonal branches (D1/2 dominancy) was a binary attribute for one of two diagonal branches whose diameter was more than two times larger than its smaller counterpart. 4. LCx dominancy was defined as a left-dominant system or a presence of obtuse marginal branch originating within proximal 1/3 of LCx and crossing LAD at right anterior oblique caudal view. |
| Sensitivity of prediction model | through study completion, an average of 1year | Prediction model using anatomical attributes to define clinical relevance of diagonal branches will be developed. |
| Specificity of prediction model | through study completion, an average of 1year | Prediction model using anatomical attributes to define clinical relevance of diagonal branches will be developed. |
| Negative predictive value of prediction model | through study completion, an average of 1year | Prediction model using anatomical attributes to define clinical relevance of diagonal branches will be developed. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| %Ischemia | through study completion, an average of 1year | Myocardium of perfusion image was divided into 20 segments, and summed rest score (SRS), summed stress score (SSS), and summed difference score (SDS) were scored in each segment according to a 5-grade system (0-4) for the assessment of perfusion status. (1) SSS and SDS of diagonal segments were converted to percent of myocardial ischemia (%ischemia) of diagonal territory by dividing summed scores by 80 and multiplying by 100. |
| %FMM | through study completion, an average of 1year | FMM was calculated using stem-and-crown model as described in the parent study. (2) FMM of each diagonal brach was converted to percent FMM (%FMM) of diagonal branch by dividing each FMM by left ventricular myocardial mass. |
Countries
South Korea