ABSTRACT
Central venous obstruction sufficient to prevent primary pacemaker implantation is rare. We report on such a patient in whom removal of a very large retrosternal goitre led to subsequent procedural success.
Subject(s)
Goiter, Substernal/complications , Goiter, Substernal/surgery , Pacemaker, Artificial , Prosthesis Failure , Sick Sinus Syndrome/therapy , Subclavian Vein/surgery , Venous Insufficiency/surgery , Aged, 80 and over , Constriction, Pathologic/diagnostic imaging , Constriction, Pathologic/etiology , Constriction, Pathologic/surgery , Female , Goiter, Substernal/diagnostic imaging , Humans , Prosthesis Implantation , Radiography , Subclavian Vein/diagnostic imaging , Syncope/therapy , Treatment Outcome , Venous Insufficiency/diagnostic imaging , Venous Insufficiency/etiologyABSTRACT
OBJECTIVE: The effect of caffeine on cardiovascular health remains controversial. Patients with long-standing type 1 diabetes are at risk of autonomic failure and sudden cardiac death. We investigated the effects of caffeine on autonomic dysfunction (as assessed by heart rate variability [HRV]) in this high-risk group and in a control population. RESEARCH DESIGN AND METHODS: Using a randomized blinded, placebo-controlled, crossover design trial, we examined 2 weeks of caffeine consumption (250 mg twice daily) on HRV in 20 type 1 diabetic patients and 10 matched healthy volunteers. RESULTS: Baseline HRV was blunted in the diabetic patients (P < 0.0005 vs. control subjects) and markedly increased by caffeine in both groups (+103% in the group with diabetes [P = 0.009] and +38% in control subjects [P = 0.002]). The caffeine-associated increase in HRV was not statistically different between the control and the type 1 diabetes groups (P = 0.16). CONCLUSIONS: Modest amounts of caffeine improved autonomic function in diabetic patients and healthy volunteers. For individuals with abnormal HRV, regular caffeine use may have the potential to reduce the risk of cardiovascular events.
