Neurohormonal activation with increased plasma renin activity and norepinephrine and vasopressin levels is characteristic of congestive heart failure and contributes to further decompensation and poor prognosis. We treated 20 such patients with the centrally acting sympathoinhibitory drug clonidine 0.15 mg BID and obtained hemodynamic measurements by cardiac catheterization and plasma neurohormone levels before and 2 to 3 hours after the first dose; in 7 patients, these measurements were taken again after 1 week of therapy. The initial dose produced significant decreases of 8% in mean arterial pressure, 23% in right atrial pressure, 21% in pulmonary capillary wedge pressure, 19% in mean pulmonary artery pressure, and 12% in heart rate, a 17% increase in stroke volume; and no significant changes in cardiac output and systemic vascular resistance. All changes remained virtually constant after 1 week. Plasma norepinephrine decreased by 28% after the initial dose and 62% after 1 week (P < 0.1), whereas plasma renin activity remained essentially unchanged. Plasma vasopressin tended to increase, its levels being inversely correlated with those of posttreatment norepinephrine (r = -.48 P < .03). Patients with baseline norepinephrine levels > 0.400 ng/mL has significantly poorer baseline hemodynamic parameters and tended to show more improvement with clonidine, although their data remained significantly worse than patients whose baseline norepinephrine was within the normal range. Sympathetic suppression with clonidine in congestive heart failure reduces preload, heart rate, and arterial pressure, all indexes of myocardial energy demand; the lack of significant reduction in systemic vascular resistance and increase in cardiac output might be attributable in part to enhanced release of vasopressin.2+ f2p4
OBJECTIVE -There are conflicting results regarding the impact of type 2 diabetes on intravenous thrombolysis effectiveness during ST elevation myocardial infarction (STEMI). The present study, using a continuous 12-lead electrocardiogram, examined the possible association of type 2 diabetes with both acute intravenous thrombolysis effectiveness and long-term prognosis in this setting.RESEARCH DESIGN AND METHODS -The study included 726 consecutive subjects (214 type 2 diabetic subjects) with STEMI who received intravenous thrombolysis in the first 6 h from index pain and were followed up for 3.5 years.RESULTS -Type 2 diabetic subjects had significantly lower incidence of sustained Ն50% ST recovery than nondiabetic subjects (P ϭ 0.03). Additionally, the former required a significantly greater time interval through the achievement of this criterion than the latter (P Ͻ 0.001). In both type 2 diabetic (P Ͻ 0.001) and nondiabetic subjects (P Ͻ 0.001), those who had not attained Ն50% ST recovery were at significantly higher risk of cardiac death than subjects who had reached this criterion. The subjects who attained the above electrocardiographic criterion in Ն60 min after thrombolysis initiation were at significantly higher risk compared with those who achieved this criterion in Ͻ60 min (P ϭ 0.02). However, this association was true only for type 2 diabetic subjects (P ϭ 0.01) and not for nondiabetic subjects (P ϭ 0.9).CONCLUSIONS -The present study suggests that type 2 diabetes is a strong predictor of acute intravenous thrombolysis failure during STEMI. This finding may significantly contribute to the worse prognosis for type 2 diabetic subjects compared with nondiabetic ones in this setting.
This study was designed to evaluate in 45 hypertensive patients with left ventricular hypertrophy (LVH) the effects of a 6-month course with one of three different antihypertensive regimens (the calcium channel blocker isradipine, the angiotensin converting enzyme inhibitor spirapril in monotherapy, or a combination of the two drugs, n = 15 per group) on blood pressure, LVH regression, and various functional correlates of LVH. All three treatment modalities decreased significantly LV mass index by an average of 10%, although the combination had the greatest blood pressure-lowering effect and spirapril had the least, as assessed by office resting pressures, ambulatory monitoring, and isometric grip testing. There was no correlation between magnitude of blood pressure lowering and degree of LVH regression. The effects of treatment on pressor hormone profiles differed among groups, as spirapril tended to suppress angiotensin II and norepinephrine, whereas isradipine had opposite effects. Exercise tolerance was prolonged by all three regimens, but significantly more by the combination. All three regimens decreased significantly the double product by 10% to 15%. Indices of electrophysiologic stability calculated from analysis of ambulatory electrocardiogram exhibited significant improvement in several parameters such as QRS duration, presence of late potentials, and measures of heart rate variability, resulting in fewer episodes of simple or complex ventricular arrhythmia. We conclude that all three regimens produce significant LVH regression associated with improved functional capacity and electrical stability. These results reflect the sum of the differential hemodynamic and hormonal effects exerted by each treatment modality.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.