Acute systemic and coronary hemodynamic and serologic responses to cigarette smoking in long-term smokers with atherosclerotic coronary artery disease.

Previous studies suggested that cigarette smoking 1) inhibits an increase in coronary blood flow that should occur with increased myocardial oxygen demands, and 2) alters thromboxane and prostacyclin production, causing vasoconstriction and platelet aggregation. In 38 smokers (26 men and 12 women, aged 50 +/- 8 years [mean +/- standard deviation] ) with coronary artery disease, systemic and coronary hemodynamic and serologic variables were measured before and after smoking two cigarettes (in 8 to 10 minutes) (21 patients) or 8 to 10 minutes without smoking (17 patients; control group). No variable changed in the control group. Smoking increased (p less than 0.05) heart rate-systolic pressure product, cardiac output and maximal first derivative of left ventricular pressure (dP/dt) without significantly changing the coronary sinus concentrations of thromboxane B2 or 6-keto-prostaglandin F1 alpha (the stable metabolites of thromboxane A2 and prostacyclin, respectively). Smoking did not increase coronary flow in 6 of 11 patients with greater than 70% stenosis of the proximal left anterior descending or circumflex coronary artery, or both, whereas it caused an increase in coronary flow in all 10 patients without proximal stenoses (p = 0.006). To determine if smoking altered the response of coronary flow to increased myocardial oxygen demands, 10 smokers (5 men and 5 women, aged 48 +/- 9 years) underwent atrial pacing for 5 minutes followed 15 minutes later by atrial pacing for 5 minutes during smoking. In the five patients without proximal left coronary artery stenoses, coronary flow increased 26 +/- 29 ml/min with pacing and 45 +/- 21 ml/min with pacing/smoking (p = 0.018).(ABSTRACT TRUNCATED AT 250 WORDS)