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An open, dose-titration study of alfuzosin, a new selective post-synaptic alpha 1-adrenoceptor antagonist with additional direct vasodilator properties has been performed. After a 3-week run-in placebo period, 12 patients with essential hypertension received alfuzosin 5 mg oral b.d., and then the dose was doubled every week, up to a maximum of 20 mg q.i.d. if the supine diastolic blood pressure was greater than 90 mm Hg. The study lasted for 4 weeks. Supine blood pressure (SBP) decreased from 160/102 (Day 0) to 148/89 mm Hg and upright blood pressure (UBP) from 151/102 (Day 0) to 137/84 mm Hg. Alfuzosin did not cause any significant change in supine or upright heart rate. In addition, after the first dose of alfuzosin, supine and upright blood pressure and heart rate (SHR and UHR) were measured every 30 min for 5 h. The fall in blood pressure was significant after 90 min and it lasted up to the 5th hour; the maximum effect was observed after 3 h: SBP decreased from 159/103 (time 0) to 137/84 mm Hg and UBP from 150/102 (time 0) to 123/79 mm Hg. SHR was increased from 72 (time 0) to 81 beats/min at the 5th hour and UHR from 87 to 101 beats/min at the 4th hour. A weak but significant correlation was observed between the hypotensive effect 12 h after drug intake and the plasma concentration of the drug at that time. A 10% decrease in supine diastolic blood pressure was found at a drug plasma concentration higher than 7 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

SUMMARY Eighteen patients with chronic aortic insufficiency were evaluated hemodynamically and angiographically 8 months after aortic valve replacement. Both the pulmonary artery diastolic pressure and the left ventricular end-diastolic volume decreased significantly (p < 0.001), but the mean ejection fraction and the cardiac output remained identically lowered, though some individual cases showed improvement. The relative reduction in end-diastolic volume correlated only with the preoperative ejection (p < 0.05) and regurgitation fractions (p < 0.02).In the 10 patients whose left ventricular volume remained high or ejection fraction low, a second evaluation was performed 27 months after surgery. The left ventricular end-diastolic volume was significantly lowered (from 151 to 120 mI/m2, p < 0.05) back to normal in five cases. The systolic and diastolic ventricular shape returned to normal. Cardiac index and ejection fraction were unchanged.These results show a marked improvement a few months after aortic valve replacement, with a further improvement several months later, as shown mainly by the decrease of left ventricular end-diastolic volume and the return to normal of left ventricular cavity shape. However, in most cases, the ejection fraction remained at its preoperative value, suggesting that surgery should be performed early, before myocardial deterioration appears.AORTIC REGURGITATION produces no clinical symptoms at first1' 2 because the left ventricle is initially the only cardiac chamber involved and can compensate for the regurgitation. During this time, the total cardiac volume increases slowly, pulmonary pressures remain normal, and left ventricular function shows no evidence of change. The alteration in left ventricular function is, however, a major factor in the postoperative prognosis.37The best time for valve replacement is difficult to determine, despite precise clinical, hemodynamic and angiographic data, because the relative risks involved in the consequences of prolonged aortic regurgitation, and those inherent in surgery and prosthetic valves, are not easy to determine.Evaluation of the results of valve replacement in relation to the pre-and postoperative hemodynamic and angiographic findings has only been undertaken in a few studies that, for the most part, involved few patients.8"-' The aim of the present study was to determine which preoperative factors have a prognostic value, to assess the reversibility of the left ventricular changes and to ascertain the optimal time for valve replacement. 18-65 years), suffering from an isolated, marked, long-standing aortic regurgitation. Its etiology was rheumatic in 10 cases, infective endocarditis in six and unknown in the other two. No patient had associated coronary disease and coronary arteriography, systematically performed in the 15 patients over 40 years old, was normal. Eleven patients were in functional class I or II of the New York Heart Association and seven were in class III or IV. Seventeen showed an increase in heart size on a standar...

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In order to study the circulatory changes induced by maximal atrial pacing in coronary patients, coronary sinus blood flow (CBF) measured by continuous thermodilution, lactate extraction coefficient (K), arteriovenous difference in oxygen (AVO2 diff), and aortic blood pressure (BP) were measured at basal state and at maximal heart rate (HRmax) in 11 patients without coronary disease (group I) and in 28 patients with severe coronary lesions, divided into two groups according to the absence (group IIa) or the presence (group IIb) of chest pain and ST-segment depression at HRmax X K was inverted in group IIb (24 +/- 17% vs -23 +/- 39%, p less than 0.001), but remained unchanged in group I and group IIa. Despite similar HRmax, percent increase in CBF was significantly lower in group IIb (54 +/- 34%), than in group I (113 +/- 54%, p less than 0.01). This contrasts with the higher values of the product of heart rate times systolic blood pressure (HR X SBP) as well as of diastolic blood pressure (DBP) in group IIb. The decrease in coronary resistances was lower in group IIb than in group I (p less than 0.001), and also lower than in group IIa (p less than 0.05). The ratio MVO2 X CBF/systolic BP X HRmax was significantly lowered only in group IIb (p less than 0.001) confirming the imbalance between myocardial oxygen supply and oxygen demand. In coronary patients, myocardial ischemia induced by atrial pacing is related to an insufficient increase in CBF, well evidenced by continuous thermodilution.