ABSTRACT
OBJECTIVE: To explore possible differential effects between metoprolol and atenolol in patients with coronary artery disease. DESIGN: The study was randomized, double blind, two-way crossover with the Y1 antagonist AR-H040922 given as IV infusion for 2 h or placebo. Most patients were treated with metoprolol or atenolol. In a post hoc analysis we compared the hemodynamic response to exercise of the Y1 antagonist in patients on metoprolol (n = 16) and atenolol (n = 5), and assessed respiratory sinus arrhythmia (RSA), an indirect measurement of cardiac vagal activation, in the placebo phase in patients on metoprolol (n = 26) and on atenolol (n = 24). RESULTS: 1) The Y1 antagonist reduced the systolic blood pressure rise during and after exercise during atenolol, but not during metoprolol, while heart rate and maximal load were similar with the two beta-blockers and not affected by the Y1 antagonist. 2) At equal heart- and respiration-rate 7-8 min after exercise the RSA was significantly lower in atenolol than in metoprolol patients, while no difference was seen at rest before exercise. CONCLUSION: These findings from this hypothesis generating study indicate that peripheral effects of NPY contribute less to cardiovascular stress reactions in patients on metoprolol than in those on atenolol.
Subject(s)
Adrenergic beta-1 Receptor Antagonists/pharmacology , Angina, Stable/physiopathology , Atenolol/pharmacology , Metoprolol/pharmacology , Neuropeptide Y/antagonists & inhibitors , Adrenergic beta-1 Receptor Antagonists/administration & dosage , Adrenergic beta-1 Receptor Antagonists/therapeutic use , Adult , Aged , Angina, Stable/therapy , Atenolol/administration & dosage , Atenolol/therapeutic use , Blood Pressure/drug effects , Coronary Artery Disease/physiopathology , Coronary Artery Disease/therapy , Double-Blind Method , Exercise/physiology , Heart Rate/drug effects , Humans , Male , Metoprolol/administration & dosage , Metoprolol/therapeutic use , Middle Aged , Neuropeptide Y/bloodABSTRACT
BACKGROUND: Inflammation and matrix degradation may play a pathogenic role in chronic heart failure (CHF), and therefore, we examined whether thalidomide, a drug with potential immunomodulating and matrix-stabilizing properties, could improve left ventricular (LV) function in patients with CHF secondary to idiopathic dilated cardiomyopathy (IDCM) or coronary artery disease (CAD). METHODS AND RESULTS: Fifty-six patients with CHF and an LV ejection fraction (LVEF) <40% who were already on optimal conventional cardiovascular treatment were randomized to thalidomide (25 mg QD increasing to 200 mg QD) or placebo and followed up for 12 weeks. Our main findings were as follows: (1) During thalidomide treatment but not during placebo, there was a marked increase in LVEF (&7 EF units) along with a significant decrease in LV end-diastolic volume and heart rate. (2) This improvement in LVEF was accompanied by a decrease in matrix metalloproteinase-2 without any changes in its endogenous tissue inhibitor, suggesting a matrix-stabilizing net effect. (3) Thalidomide also induced a decrease in total neutrophil count and an increase in plasma levels of tumor necrosis factor-alpha, suggesting both proinflammatory and antiinflammatory effects. (4) The effect of thalidomide on LVEF was more marked in IDCM than in CAD, possibly partly reflecting that the former group was able to tolerate a higher thalidomide dosage. CONCLUSIONS: Although our results must be confirmed in larger studies that also examine the effects on morbidity and mortality, our findings suggest a role for thalidomide in the management of CHF in addition to traditional cardiovascular medications.