Characteristic patterns of the longitudinal and circumferential distribution of calcium deposits by parent coronary arteries observed from computed tomography angiography

Intraoperative transit-time flow measurement and high-frequency ultrasound in coronary artery bypass grafting: impact in off versus on-pump, arterial versus venous grafting and cardiac territory grafted

OBJECTIVES

Despite society guideline recommendations, intraoperative high-frequency ultrasound (HFUS) and transit-time flow measurement (TTFM) use in coronary artery bypass grafting (CABG) has not been widely adopted worldwide. This retrospective review of the REQUEST (REgistry for QUality assESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery) study assesses the impact of protocolled high-frequency ultrasound/TTFM use in specific technical circumstances of CABG.

METHODS

Three REQUEST study sub-analyses were examined: (i) For off-pump (OPCAB) versus on-pump (ONCAB) procedures: strategy changes from preoperative plans for the aorta, conduits, coronary targets and graft revisions; and for all REQUEST patients, revision rates in: (ii) arterial versus venous grafts; and (iii) grafts to different cardiac territories.

RESULTS

Four hundred and two (39.6%) of 1016 patients undergoing elective isolated CABG for multivessel disease underwent OPCAB procedures. Compared to ONCAB, OPCAB patients experienced more strategy changes regarding the aorta [14.7% vs 3.4%; odds ratios (OR) = 4.03; confidence interval (CI) = 2.32-7.20], less regarding conduits (0.2% vs 2.8%; OR = 0.09; CI = 0.01-0.56), with no differences in coronary target changes or graft revisions (4.1% vs 3.5%; OR = 1.19; CI = 0.78-1.81). In all REQUEST patients, revisions were more common for arterial versus venous grafts (4.7% vs 2.4%; OR = 2.05; CI = 1.29-3.37), and inferior versus anterior (5.1% vs 2.9%; OR = 1.77; CI = 1.08-2.89) and lateral (5.1% vs 2.8%; OR = 1.83; CI = 1.04-3.27) territory grafts.

CONCLUSIONS

High-frequency ultrasound/TTFM use differentially impacts strategy changes and graft revision rates in different technical circumstances of CABG. Notably, patients undergoing OPCAB experienced 4 times more changes related to the ascending aorta than ONCAB patients. These findings may indicate where intraoperative assessment is most usefully applied.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT02385344.

Reduced Axial Scan Length Coronary Calcium Scoring Reduces Radiation Dose and Provides Adequate Clinical Decision-Making Before Coronary CT Angiography

Extensive coronary artery calcium (CAC) diminishes the accuracy of coronary computed tomography angiography (CCTA). Many imagers adjust CCTA acquisition parameters depending on a preCCTA Agatston CAC score to optimize diagnostic accuracy. Typical preCCTA CAC imaging adds considerably to radiation exposure, partially attributable to imaging beyond the area known for highest CAC, the proximal coronary arteries. We aimed to determine whether a z-axis reduced scan length (RSL) would identify the majority of CAC and provide adequate information to computed tomography angiography providers relative to a standard full-scan length (FSL) preCCTA noncontrast CT. We retrospectively examined 200 subjects. The mean CAC scores detected in RSL and FSL were 77.4 (95% CI 50.6 to 104.3) and 93.9 (95% CI 57.3 to 130.5), respectively. RSL detected 81% of the FSL CAC. Among false negatives, with no CAC detected in RSL, FSL CAC severity was minimal (mean score 2.8). There was high concordance, averaging 88%, between CCTA imaging parameter adjustment decisions made by 2 experienced imagers based on either RSL or FSL. CAC detected and decision concordance decreased with increasing CAC burden. CAC detected was lower, and false negatives were more common in the right coronary artery owing to its anatomic course, placing larger segments outside RSL. Axial scan length and effective dose decreased 59% from FSL (∼14.5 cm/∼1.1 mSv) to RSL (∼5.9 cm/∼0.45 mSv). This retrospective study suggests that RSL identifies most CAC, results in similar CCTA acquisition parameter modifications, and reduces radiation exposure. Our colleagues corroborated these results in a recently published prospective study.

Proximal left anterior descending coronary artery stenosis should be considered when using the prognostic value of the residual SYNTAX score: Data from 10343 consecutive patients with long-term follow up in the real world

OBJECTIVES

The purpose of this study was to assess the prognostic significance of the residual SYNTAX score (rSS) in a large-scale cohort of consecutive percutaneous coronary intervention (PCI) patients and to analyze whether residual proximal left anterior descending coronary artery (pLAD) lesions affect the prognosis of patients with same or similar rSS levels.

BACKGROUND

The rSS, measured after PCI, has been assessed as an independent predictor of long-term clinical outcome and a tool for quantification of incomplete revascularization, and still needs to be validated in various PCI populations. When using rSS to determine an objective level of reasonable incomplete revascularization, it is currently undefined whether a pLAD lesion deserves more attention.

METHODS

The calculations of baseline SYNTAX scores (bSS) and rSS were performed in 10,343 consecutive patients undergoing PCI in Fuwai Hospital from January 2013 to December 2013. The primary endpoint was major adverse cardiac events (MACE), defined as a composite of all-cause death, myocardial infarction (MI), and any revascularization. Secondary endpoints included the individual components of the MACE, cardiac death, and all-cause death/MI.

RESULTS

MACE and cardiac death rates were significantly higher among patients with residual pLAD stenosis ≥70%. rSS and residual pLAD stenosis ≥70% were both strong independent predictors of MACE. Compared with rSS, rSS plus residual pLAD stenosis was superior in predicting 30-month MACE (P = .0016).

CONCLUSIONS

rSS is a strong independent predictor of long-term adverse clinical outcomes. Residual pLAD lesions affect the prognosis of patients with same or similar rSS levels.

Sex-related differences in serum matrix metalloproteinase-9 screening non-calcified and mixed coronary atherosclerotic plaques in outpatients with chest pain

The objective of this study is to evaluate the clinical feasibility of serum matrix metalloproteinase-9 (MMP-9) for screening plaque composition as assessed by coronary computed tomography angiography (CCTA) in outpatients with chest pain,and the effects of sex on this feasibility. Eight hundred and sixty-two consecutive outpatients with chest pain were divided into three groups according to the results of CCTA: non-plaque (NP, n = 474), calcified plaques (CPs, n = 179), non-calcified and mixed plaques (NCPs and MPs, n = 209). We found that serum MMP-9 levels were significantly higher in patients with NCPs and MPs compared to those with either NP or CPs, especially in women (649.7 ± 279.8 vs. 485.7 ± 231.6 ng/mL or 515.7 ± 274.5 ng/mL, P < 0.001). MMP-9 showed better identification of NCPs and MPs than other related factors and was an independent predictor for NCPs and MPs both in women and men. The receiver operating characteristic analysis indicated a substantial superiority in women with area under the curve of 0.75 (95% CI 0.69-0.82, P < 0.01), compared with men of 0.59 (95% CI 0.53-0.65, z = 3.71, P < 0.01). The diagnostic tests revealed a moderate risk of the presence of NCPs and MPs with MMP-9 ≥531.6 ng/mL in female patients.

Predominant location of coronary artery atherosclerosis in the left anterior descending artery. The impact of septal perforators and the myocardial bridging effect

Introduction

Coronary artery atherosclerosis presents characteristic patterns of plaque distribution despite systemic exposure to risk factors. We hypothesized that local hemodynamic forces induced by the systolic compression of intramuscular septal perforators could be involved in atherosclerotic processes in the left anterior descending artery (LAD) adjacent to the septal perforators’ origin. Therefore we studied the spatial distribution of atherosclerosis in coronary arteries, especially in relation to the septal perforators’ origin.

Material and methods

64-slice computed tomography angiography was performed in 309 consecutive patients (92 male and 217 female) with a mean age of 59.9 years. Spatial plaque distribution in the LAD was analyzed in relation to the septal perforators’ origin. Additionally, plaque distribution throughout the coronary artery tree is discussed.

Results

The coronary calcium score (CCS) was positive in 164 patients (53.1%). In subjects with a CCS > 0, calcifications were more frequent in the LAD (n = 150, 91.5%) compared with the right coronary artery (RCA) (n = 94, 57.3%), circumflex branch (CX) (n = 76, 46.3%) or the left main stem (n = 42, 25.6%) (p < 0.001). Total CCS was higher in the LAD at 46.1 (IQR: 104.2) and RCA at 34.1 (IQR: 90.7) than in the CX at 16.8 (IQR: 61.3) (p = 0.007). In patients with calcifications restricted to a single vessel (n = 54), the most frequently affected artery was the LAD (n = 42, 77.8%). In patients with lesions limited to the LAD, the plaque was located mostly (n = 37, 88.1%) adjacent to the septal perforators’ origin.

Conclusions

We demonstrated that coronary calcifications are most frequently located in the LAD in proximity to the septal branch origin. A possible explanation for this phenomenon could be the dynamic compression of the tunneled septal branches, which may result in disturbed blood flow in the adjacent LAD segment (milking effect).