Atheromatous plaque reflects serum total cholesterol levels: a comparative morphologic study of endarterectomy coronary atherosclerotic plaques removed from patients from the southern part of India and Caucasians from Ottawa, Canada

A weighted angiographic scoring model (W-CTO score) to predict success of antegrade wire crossing in chronic total occlusion: analysis from a single centre

AIMS

The aim of this study was to derive a weighted score model predicting success/failure of antegrade wire crossing in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS AND RESULTS

Four hundred and four consecutive CTO cases (408 lesions) undergoing CTO-PCI between January 2009 and March 2015 were included. Data were divided into two sets, namely "derivation" and "validation", in a 70:30 ratio. The score was derived using multivariate analysis to identify independent predictors of wire crossing failure from the derivation set (n=285 lesions) and validated on the remaining 123 lesions (validation set). The overall procedural success rate was 83.6%. Independent predictors of CTO-PCI failure and their contribution to the weighted score were a blunt stump (beta coefficient 2.12), length of occlusion >20 mm (beta coefficient 1.71), presence of calcification (beta coefficient 0.72), presence of tortuosity (beta coefficient 1.06) and collateral with Rentrop grade <2 (beta coefficient 1.06). The respective scores allotted were +2.0, +1.5, +1, +1, +1 (total 6.5), rounding the coefficient to the nearest 0.5. Score values of 0-2, >2-4 and >4 were classified as low, intermediate and high levels of difficulty for CTO-PCI success and were associated with 98%, 74.2%, and 42.5% (p<0.0001), respectively, of antegrade wire crossing success in the derivation set. This was also validated on the validation set with CTO success in the three derived difficulty levels being 100%, 82.4% and 48.4%, respectively.

CONCLUSIONS

Our weighted angiographic CTO score is a strong predictor of final antegrade wire crossing success and could be used in day-to-day clinical practice of CTO interventions.

Coronary fat content evaluated by morphometry in patients with severe atherosclerosis has no relation with serum lipid levels

The relationship between lipid serum levels and coronary atherosclerotic plaque fat content was studied in 51 necropsy patients. Serum lipids were measured by standard techniques, during life, in the absence of lipid-lowering drugs. Intima, intimal fat and media areas were measured using a computerized system in cryosections of the odd segments of the right, anterior descending and circumflex coronary arteries stained with Sudan-IV. Mean intimal and lipid areas were 5.74 +/- 1.98 and 1.22 +/- 0.55 mm2 (22.12 +/- 8.48%) in 26 cases with high cholesterol (>or=200 mg/dL) and 4.98 +/- 1.94 and 1.16 +/- 0.66 mm2 (22.75 +/- 9.06%) in 25 cases with normal cholesterol (<200 mg/dL; P > 0.05). Patients with high levels of low-density lipoprotein (>or=130 mg/dL, N = 15) had a higher intima/media area ratio than those with normal levels of low-density lipoprotein (<130 mg/dL, N = 13, P < 0.01). No significant difference in the morphometrical variables was found in groups with high or low serum levels of triglycerides (>or=200 mg/dL, N = 13 vs <200 mg/dL, N = 36) or high-density lipoprotein (>or=35 mg/dL, N = 11 vs <35 mg/dL, N = 17). The association between the morphological measurements and serum levels of cholesterol, its fractions, and triglycerides was also tested and the correlation coefficients were low. Although high cholesterol is a risk factor, we show here that in patients with severe atherosclerosis blood cholesterol and triglyceride levels seem to have little influence on coronary lipid content, indicating that other factors may contribute to arterial lipid deposition and plaque formation.

Relation Between Progression and Regression of Atherosclerotic Left Main Coronary Artery Disease and Serum Cholesterol Levels as Assessed With Serial Long-Term (≥12 Months) Follow-Up Intravascular Ultrasound

Background— The relation between serum lipids and risk of coronary events has been established, but there are no data demonstrating directly the relation between serum low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol versus serial changes in coronary plaque dimensions.

Methods and Results— We performed standard analyses of serial intravascular ultrasound (IVUS) studies of 60 left main coronary arteries obtained 18.3±9.4 months apart to evaluate progression and regression of mild atherosclerotic plaques in relation to serum cholesterol levels. Overall, there was (1) a positive linear relation between LDL cholesterol and the annual changes in plaque plus media (P&M) cross-sectional area (CSA) ( r =0.41, P <0.0001) with (2) an LDL value of 75 mg/dL as the cutoff when regression analysis predicted on average no annual P&M CSA increase; (3) an inverse relation between HDL cholesterol and annual changes in P&M CSA ( r =−0.30, P <0.02); (4) an inverse relation between LDL cholesterol and annual changes in lumen CSA ( r =−0.32, P <0.01); and (5) no relation between LDL and HDL cholesterol and the annual changes in total arterial CSA (remodeling). Despite similar baseline IVUS characteristics, patients with an LDL cholesterol level ≥120 mg/dL showed more annual P&M CSA progression and lumen reduction than patients with lower LDL cholesterol.

Conclusions— There is a positive linear relation between LDL cholesterol and annual changes in plaque size, with an LDL value of 75 mg/dL predicting, on average, no plaque progression. HDL cholesterol shows an inverse relation with annual changes in plaque size.

Angiogenic protein therapy

Therapeutic angiogenesis, in the form of growth factor protein administration or gene therapy, has emerged as a new method of treatment for patients with severe, inoperable coronary artery disease. Improved myocardial perfusion and function after the administration of angiogenic growth factors has been demonstrated in animal models of chronic myocardial ischemia. A recent clinical study reported beneficial long-term effects of therapeutic angiogenesis using FGF-2 protein in terms of freedom from angina and myocardial perfusion on nuclear imaging and suggested that protein angiogenic therapy has the potential to extend treatment options to patients who are not optimal candidates for conventional methods of myocardial revascularization. The ultimate role that angiogenesis will play in the treatment of ischemic heart disease will, however, be determined from adequately powered, randomized, double-blind, placebo-controlled trials. It is likely that endogenous antiangiogenic influences, intrinsic lack of response of patients with severe endothelial dysfunction, and other limitations will have to be overcome before angiogenesis becomes standard therapy for the treatment of coronary artery disease.