The association between the extent of lipidic burden and delta-fractional flow reserve: analysis from coronary physiological and near-infrared spectroscopic measures

Change in Pd/Pa: Clinical Implications for Predicting Future Cardiac Events at Deferred Coronary Lesions

BACKGROUND

Cardiovascular events still occur at intermediate stenosis with fractional flow reserve (FFR) ≥0.81, underscoring the additional measure to evaluate this residual risk. A reduction in distal coronary artery pressure/aortic pressure (Pd/Pa) from baseline to hyperemia (ie, change in Pd/Pa) reflects lipidic burden within vessel walls. We hypothesized that this physiological measure might stratify the risk of future cardiac events at deferrable lesions.

METHODS

Lesion- (899 intermediate lesions) and patient-based (899 deferred patients) analyses in those with FFR ≥0.81 were conducted to investigate the association between change in Pd/Pa and target lesion failure (TLF) and major adverse cardiac events at 7 years, respectively.

RESULTS

The occurrence of TLF and major adverse cardiac events was 6.7% and 13.4%, respectively. The incidence of target lesion-related nonfatal myocardial infarction was 0.6%. Lesions with TLF had a greater change in Pd/Pa (0.11±0.03 versus 0.09±0.04; P=0.002), larger diameter stenosis (51.0±9.2% versus 46.4±12.4%; P=0.048), and smaller FFR (0.84 [0.82-0.87] versus 0.86 [0.83-0.90]; P=0.02). Change in Pd/Pa (per 0.01 increase) predicted TLF (odds ratio, 1.16 [95% CI, 1.05-1.28]; P=0.002) and major adverse cardiac event (odds ratio, 1.08 [95% CI, 1.01-1.16]; P=0.03). Lesions with change in Pd/Pa ≥0.10 had 2.94- and 1.85-fold greater likelihood of TLF (95% CI, 1.30-6.69; P=0.01) and major adverse cardiac event (95% CI, 1.08-3.17; P=0.03), respectively. Lesions with FFR ≤0.85 had a substantially higher likelihood of TLF when there is a change in Pd/Pa ≥0.10 (12.4% versus 2.9%; hazard ratio, 3.60 [95% CI, 1.01-12.80]; P=0.04). However, change in Pd/Pa did not affect TLF risk in lesions with FFR ≥0.86 (3.8% versus 3.7%; hazard ratio, 0.56 [95% CI, 0.06-5.62]; P=0.62).

CONCLUSIONS

Despite deferrable FFR values, lesions and patients with a change in Pd/Pa ≥0.10 had higher cardiovascular risk. Change in Pd/Pa might help stratify lesion- and patient-level risks of future cardiac events in those with FFR ≥0.81.

Glucagon-like Peptide-1 analogues and delipidation of coronary atheroma in statin-treated type 2 diabetic patients with coronary artery disease: The prespecified sub-analysis of the OPTIMAL randomized clinical trial

Background and aims

Randomized clinical trials have demonstrated the ability of glucagon-like peptide-1 analogues (GLP-1RAs) to reduce atherosclerotic cardiovascular disease events in patients with type 2 diabetes (T2D). How GLP-1RAs modulate diabetic atherosclerosis remains to be determined yet.

Methods

The OPTIMAL study was a prospective randomized controlled study to compare the efficacy of 48-week continuous glucose monitoring- and HbA1c-guided glycemic control on near infrared spectroscopty (NIRS)/intravascular ultrasound (IVUS)-derived plaque measures in 94 statin-treated patients with T2D (jRCT1052180152, UMIN000036721). Of these, 78 patients with evaluable serial NIRS/IVUS images were analyzed to compare plaque measures between those treated with (n = 16) and without GLP-1RAs (n = 72).

Results

All patients received a statin, and on-treatment LDL-C levels were similar between the groups (66.9 ± 11.6 vs. 68.1 ± 23.2 mg/dL, p = 0.84). Patients receiving GLP-1RAs demonstrated a greater reduction of HbA1c [-1.0 (-1.4 to -0.5) vs. -0.4 (-0.6 to -0.2)%, p = 0.02] and were less likely to demonstrate a glucose level >180 mg/dL [-7.5 (-14.9 to -0.1) vs. 1.1 (-2.0 - 4.2)%, p = 0.04], accompanied by a significant decrease in remnant cholesterol levels [-3.8 (-6.3 to -1.3) vs. -0.1 (-0.8 - 1.1)mg/dL, p = 0.008]. On NIRS/IVUS imaging analysis, the change in percent atheroma volume did not differ between the groups (-0.9 ± 0.25 vs. -0.2 ± 0.2%, p = 0.23). However, GLP-1RA treated patients demonstrated a greater frequency of maxLCBI4mm regression (85.6 ± 0.1 vs. 42.0 ± 0.6%, p = 0.01). Multivariate analysis demonstrated that the GLP-1RA use was independently associated with maxLCBI4mm regression (odds ratio = 4.41, 95%CI = 1.19-16.30, p = 0.02).

Conclusions

In statin-treated patients with T2D and CAD, GLP-1RAs produced favourable changes in lipidic plaque materials, consistent with its stabilization.

The effect of continuous glucose monitoring-guided glycemic control on progression of coronary atherosclerosis in type 2 diabetic patients with coronary artery disease: The OPTIMAL randomized clinical trial

BACKGROUND

Continuous glucose monitoring (CGM) improves glycemic fluctuation and reduces hypoglycemic risk. Whether CGM-guided glycemic control favorably modulates coronary atherosclerosis in patients with type 2 diabetes (T2DM) remains unknown.

METHODS

The OPTIMAL trial was a prospective, randomized, single-center trial in which 94 T2DM patients with CAD were randomized to CGM- or HbA1c-guided glycemic control for 48 weeks (jRCT1052180152). The primary endpoint was the nominal change in total atheroma volume (TAV) measured by serial IVUS. The secondary efficacy measure was the nominal change in maxLCBI4mm on near-infrared spectroscopy imaging.

RESULTS

Among the 94 randomized patients, 82 had evaluable images at 48 weeks. Compared to HbA1c-guided glycemic control, CGM-guided control achieved a greater reduction in %coefficient of variation [-0.1 % (-1.8 to 1.6) vs. -3.3 % (-5.1 to -1.5), p = 0.01] and a greater increase in the duration with glucose between 70 and 180 mg/dL [-1.5 % (-6.0 to 2.9) vs. 6.7 % (1.9 to 11.5), p = 0.02]. TAV increased by 0.11 ± 1.9 mm3 in the HbA1c-guided group and decreased by -3.29 ± 2.00 mm3 in the CGM-guided group [difference = -3.4 mm3 (95%CI: -8.9 to 2.0 mm3), p = 0.22]. MaxLCBI4mm, increased by 90.1 ± 25.6 in the HbA1c-guided group and by 50.6 ± 25.6 in the CGM-guided group (difference = -45.6 (95%CI: -118.1 to 26.7) p = 0.21]. A post-hoc exploratory analysis showed a greater regression of maxLCBI4mm in the CGM-guided group [difference = 20.4 % (95%CI:1.3 to 39.5 %), p = 0.03].

CONCLUSIONS

CGM-guided control for 48 weeks did not slow disease progression in T2DM patients with CAD. A greater regression of lipidic plaque under CGM-guided glycemic control in the post-hoc analysis requires further investigation.

Impact of alirocumab on plaque regression and haemodynamics of non-culprit arteries in patients with acute myocardial infarction: a prespecified substudy of the PACMAN-AMI trial

BACKGROUND

Treatment with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on top of statins leads to plaque regression and stabilisation. The effects of PCSK9 inhibitors on coronary physiology and angiographic diameter stenosis (DS%) are unknown.

AIMS

This study aimed to investigate the effects of the PCSK9 inhibitor alirocumab on coronary haemodynamics as assessed by quantitative flow ratio (QFR) and DS% by three-dimensional quantitative coronary angiography (3D-QCA) in non-infarct-related arteries (non-IRA) among acute myocardial infarction (AMI) patients.

METHODS

This was a prespecified substudy of the randomised controlled PACMAN-AMI trial, comparing alirocumab versus placebo on top of rosuvastatin. QFR and 3D-QCA were assessed at baseline and 1 year in any non-IRA ≥2.0 mm and 3D-QCA DS% >25%. The prespecified primary endpoint was the number of patients with a mean QFR increase at 1 year, and the secondary endpoint was the change in 3D-QCA DS%.

RESULTS

Of 300 enrolled patients, 265 had serial follow-up, of which 193 underwent serial QFR/3D-QCA analysis in 282 non-IRA. At 1 year, QFR increased in 50/94 (53.2%) patients with alirocumab versus 40/99 (40.4%) with placebo (Δ12.8%; odds ratio 1.7, 95% confidence interval [CI]: 0.9 to 3.0; p=0.076). DS% decreased by 1.03±7.28% with alirocumab and increased by 1.70±8.27% with placebo (Δ-2.50%, 95% CI: -4.43 to -0.57; p=0.011).

CONCLUSIONS

Treatment of AMI patients with alirocumab versus placebo for 1 year resulted in a significant regression in angiographic DS%, whereas no overall improvement of coronary haemodynamics was observed.

CLINICALTRIALS

gov: NCT03067844.

The Residual Lipid-Rich Coronary Atheroma Behind the Implanted Newer-Generation Drug-Eluting Stent and Future Stent-Related Event Risks

BACKGROUND

Lipid-rich plaque is an important substrate that causes future coronary events. However, the clinical implications of underlying plaque characteristics in coronary lesions after newer-generation drug-eluting stent (DES) implantation remain unknown.

METHODS

The current study analyzed 445 target lesions after newer-generation DES implantation in 416 patients with coronary artery disease (CAD) (chronic coronary syndrome/acute coronary syndrome = 264/181) from the REASSURE-NIRS multicentre registry. Near-infrared spectroscopy (NIRS) imaging was used to evaluate maximum lipid core burden index after stent implantation in target lesions (residual maxLCBI4mm). The primary and secondary outcomes were 3-year lesion-oriented clinical outcomes (LOCO): cardiac death, nonfatal target-lesion-related myocardial infarction (MI), or ischemia-driven target-lesion revascularization (ID-TLR) and patient-oriented clinical outcomes (POCO): all-cause death, nonfatal MI, or ID unplanned revascularization. Outcomes were compared by residual maxLCBI4mm tertile.

RESULTS

Median residual maxLCBI4mm was 183; 16% of lesions had residual maxLCBI4mm > 400. Higher residual maxLCBI4mm was not associated with a greater likelihood of LOCO or POCO during the observational period (LOCO, log-rank P = 0.76; POCO, log-rank P = 0.84). Mixed-effects logistic regression demonstrated that residual maxLCBI4mm does not predict LOCO (odds ratio [OR], 1.000; 95% confidence interval [CI], 0.997-1.003; P = 0.95). There was no significant relationship between residual maxLCBI4mm and POCO (OR, 1.001; 95% CI, 0.999-1.002; P = 0.30).

CONCLUSIONS

Residual maxLCBI4mm is not associated with LOCO or POCO in patients with CAD after newer-generation DES implantation. Our findings suggest that NIRS-derived underlying lipid-rich plaque is not associated with the risk of stent-related events and patient-based outcomes in patients with CAD who have received newer-generation DESs.

Impact of coronary plaque morphology on the precision of computational fractional flow reserve derived from optical coherence tomography imaging

Background

Computational fractional flow reserve (FFR) was recently developed to expand the use of physiology-guided percutaneous coronary intervention (PCI). Nevertheless, current methods do not account for plaque composition. It remains unknown whether the numerical precision of computational FFR is impacted by the plaque composition in the interrogated vessels.

Methods

This study is an observational, retrospective, cross-sectional study. Patients who underwent both optical coherence tomography (OCT) and FFR prior to intervention between August 2011 and October 2018 at Wakayama Medical University Hospital were included. All frames from OCT pullbacks were analyzed using a deep learning algorithm to obtain coronary plaque morphology including thin-cap fibroatheroma (TCFA), lipidic plaque volume (LPV), fibrous plaque volume (FPV), and calcific plaque volume (CPV). The interrogated vessels were stratified into three subgroups: the overestimation group with the numerical difference between the optical flow ratio (OFR) and FFR >0.05, the reference group with the difference ≥-0.05 and ≤0.05, and the underestimation group with the difference <-0.05.

Results

In total 230 vessels with intermediate coronary artery stenosis from 193 patients were analyzed. The mean FFR was 0.82±0.10. Among them, 21, 179, and 30 vessels were in the overestimation, the reference, and the underestimation group, respectively. TCFA was higher in the underestimation group (60%) compared with reference (36.3%) and overestimation group (19%). Besides, it was not associated with numerical difference between OFR and FFR (NDOF) after multilevel linear regression. LPV was associated with NDOF as OFR underestimated FFR with -0.028 [95% confidence interval (CI): -0.047, -0.009] for every 100 mm3 increase in LPV.

Conclusions

High lipid burden underestimates FFR when OFR is used to assess the hemodynamic importance of intermediate coronary artery stenosis. TCFA, FPV, and CPV were not independent predictors of NDOF.

Discrepancy between plaque vulnerability and functional severity of angiographically intermediate coronary artery lesions

This study sought to investigate the relationship between physiological severity and plaque vulnerability of intermediate coronary artery stenoses as assessed by fractional flow reserve (FFR) and near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). We included vessels where both FFR and NIRS-IVUS were performed. A positive FFR was defined as FFR ≤ 0.80. Lipid core burden index of the entire target vessel (TV-LCBI), maximum LCBI in 4 mm (maxLCBI_4mm), and maximum plaque burden (PB) were evaluated using NIRS-IVUS. A vulnerable plaque was defined as a lipid-rich plaque (maxLCBI4_mm ≥ 400) with large PB (≥ 70%). A total of 59 vessels of 45 patients were included. Median FFR value was 0.75 [interquartile 0.72, 0.82]. An FFR value of ≤ 0.80 was observed in 42 vessels (71%). TV-LCBI (correlation coefficient [CC] = - 0.331, p = 0.011), lesion length (CC = - 0.350, p = 0.007), and PB (CC = - 0.230, p = 0.080) negatively correlated with FFR value, while maxLCBI_4mm did not (CC = - 0.156, p = 0.24). The prevalence of vulnerable plaques (26.2% vs. 29.4%, p > 0.99) and mean TV-LCBI, maxLCBI_4mm, and PB values were not significantly different between the vessels with FFR ≤ 0.80 and those with FFR > 0.80. In multivariable logistic models, diabetes mellitus (p = 0.003) and hemoglobin A1c (p = 0.012) were associated with the presence of a vulnerable plaque. In conclusion, the results of the present study suggested that FFR may reflect total lipid burden but not necessarily plaque vulnerability. In patients with coronary artery disease and a high likelihood of rapid atherosclerosis progression, such as diabetes mellitus patients, assessing plaque vulnerability in addition to the functional severity of coronary artery lesions may help stratify better the risk of future events.