Long-term cigarette smoking impairs endothelium-dependent coronary arterial vasodilator function

Area of Science:

• Cardiovascular Medicine
• Vascular Biology
• Atherosclerosis Research

Background:

• Smoking is a major risk factor for vascular diseases.
• The endothelium plays a crucial role in early atherosclerosis development.
• This study examines smoking's impact on endothelial function in coronary arteries.

Purpose of the Study:

• To investigate if long-term smoking impairs endothelial vasodilator function.
• To determine if this impairment occurs regardless of atherosclerotic lesions.
• To assess the relationship between smoking, endothelial function, and atherosclerosis.

Main Methods:

• Quantitative coronary angiography and intracoronary nitroglycerin were used.
• Epicardial artery diameter was measured to assess dilation.
• Flow-mediated dilation (endothelium-dependent) and nitroglycerin-induced dilation (endothelium-independent) were compared.

Main Results:

• Smokers showed significantly blunted endothelium-dependent, flow-mediated dilation compared to non-smokers.
• The ratio of flow-dependent to nitroglycerin-induced dilation was lower in smokers.
• Impaired flow-dependent dilation was observed even without visible atherosclerosis and worsened with plaque load.

Conclusions:

• Long-term smoking is linked to impaired endothelium-dependent coronary vasodilation.
• This endothelial dysfunction occurs independently of coronary atherosclerotic lesions.
• Smoking and arterial irregularities are independent predictors of reduced epicardial artery dilation.