Prognostic value of N-terminal pro-B-type natriuretic peptide for conservatively and surgically treated patients with aortic valve stenosis.

OBJECTIVE: To evaluate the prognostic value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with aortic stenosis being treated conservatively or undergoing aortic valve replacement (AVR). METHODS: 159 patients were followed up for a median of 902 days. 102 patients underwent AVR and 57 were treated conservatively. NT-proBNP at baseline was raised in association with the degree of severity and of functional status. RESULTS: During follow up 21 patients (13%) died of cardiac causes or required rehospitalisation for decompensated heart failure. NT-proBNP at baseline was higher in patients with an adverse outcome than in event-free survivors (median 623 (interquartile range 204-1854) pg/ml v 1054 (687-2960) pg/ml, p = 0.028). This difference was even more obvious in conservatively treated patients (331 (129-881) pg/ml v 1102 (796-2960) pg/ml, p = 0.002). Baseline NT-proBNP independently predicted an adverse outcome in the entire study group and in particular in conservatively treated patients (area under the curve (AUC) = 0.65, p = 0.028 and AUC = 0.82, p = 0.002, respectively) but not in patients undergoing AVR (AUC = 0.544). At a cut-off value of 640 pg/ml, baseline NT-proBNP was discriminative for an adverse outcome. CONCLUSION: NT-proBNP concentration is related to severity of aortic stenosis and provides independent prognostic information for an adverse outcome. However, this predictive value is limited to conservatively treated patients. Thus, the data suggest that assessing NT-proBNP may have incremental value for selecting the optimal timing of valve replacement.

[Mucocele of the chin area. A rare complication after genioplasty with osteocartilagenous nasal bone transplant. Review of the literature and case report]. / Die Mukozele der Kinnregion. Eine seltene Komplikation nach Genioplastik mittels osseokartilaginärem Nasenhöckertransplantat. Literaturübersicht und Fallbericht.

BACKGROUND: This paper describes an infrequent case of an intraosseous mucocele after chin augmentation using a nasal osseocartilaginous graft. Diagnostics, therapy, and clinical course of this rare complication are discussed based on our own experience and a review of the current scientific literature. CASE REPORT: Radiological examination of a 22-year-old patient revealed an oval lucent area approximately 3x1 cm in size with sclerotic rim. Cartilaginous material directly fused to the cyst wall was detected during surgery. The results of histological examination indicated parts of a cyst wall lined with respiratory epithelium located over normally maturing cartilaginous tissue. Postoperative long-term drainage with consecutive reduction of the cyst lumen was followed by cystectomy and concurrent osteoplasty and onlay graft. DISCUSSION: This case presented here is-as far as we know-one of three manifestations of a respiratory implantation cyst published. Its origin is most likely based on epithelium-like cells that have been incompletely removed from the resected nasal hump. Although severe complications of this technique have rarely been described, the surgeon must be aware of possible long-term side effects and should meticulously remove adherent nasal mucosa from the graft.

Effect of the centrally acting agent clonidine on circulating catecholamines at rest and during exercise. Comparison with the effects of beta-blocking agents.

To determine the amount of sympathetic outflow suppression due to the alpha 2-adrenergic receptor stimulating agent clonidine, its effect on heart rate, blood pressure, and on circulating plasma catecholamines was assessed in ten healthy subjects at rest and during submaximal ergometric exercise. Similar exercise studies were performed in eight healthy normotensive persons after beta-blockade using propanolol. In nine healthy subjects the effect of an acute intravenous (IV) intervention of clonidine on plasma catecholamines was compared with the results obtained after IV administration of the cardioselective beta-blocker metoprolol or of both drugs. Clonidine taken orally produced significantly reduced plasma levels of epinephrine and norepinephrine (p less than 0.01). During submaximal ergometric exercise, the sympatholytic effect of clonidine was relatively less marked than at rest (p less than 0.05). After beta-blockade, either orally with propanolol or IV with metoprolol, plasma catecholamines at rest did not change significantly; their plasma levels during exercise, however, exceeded those obtained after administration of placebo (p less than 0.05). Giving IV clonidine and metoprolol combined revealed no significant changes of plasma catecholamines at rest and during exercise; heart rate and blood pressure decreased significantly (p less than 0.001). Clonidine on the one hand and the beta-blocking agents on the other exhibit oppositely directed effects on plasma levels of catecholamines.

Altered beta-receptor responsiveness in uraemic rats.

Beta-receptor responsiveness was evaluated in 24-hour nephrectomised rats. Heart rate responses following intravenous isoproterenol injections into conscious uraemic (n = 9) and sham operated controls (n = 7) were measured. These preliminary results indicate that heart rate at rest and after blockade of the autonomic nervous system was slower in uraemic rats. Blood pressure before and after autonomic blockade was not different between groups, Maximal heart rate increase following intravenous isoproterenol was significantly less pronounced in uraemic than 0.05). The blood pressure decreasing effect of intravenous isoproterenol was enhanced in the nephrectomised group (p less than 0.01).

Myocardial catecholamine metabolism in patients with chronic aortic regurgitation.

In 17 patients suffering from severe chronic aortic regurgitation (AR) (New York Heart Association functional class III), right atrial biopsies were taken during aortic valve replacement. In these samples, we determined the myocardial content of norepinephrine (NE), normetanephrine (NM), epinephrine (E) and dopamine (DA). Two to 4 days before valve replacement, plasma catecholamines were measured at rest and during isometric exercise. Fifteen patients with secundum atrial septal defect (ASD) served as controls. In patients with chronic AR who had no clinical signs of cardiac failure, the myocardial content of NE (p less than 0.025), NM (p less than 0.05) and E (p less than 0.05) was significantly reduced compared with that in patients with ASD. The right atrial content of DA was not different in the two groups. All patients had normal levels of plasma catecholamines at rest. During isometric exercise, however, the increase in plasma NE was significantly higher in patients with AR than in the control group (p less than 0.005). We conclude that patients with chronic AR who have an exaggerated increase in sympathetic activity during isometric exercise probably have a decrease in myocardial NE tissue content as well. Therefore, clinical demonstration of a hyperadrenergic response during isometric exercise indicates alteration in myocardial metabolism in patients with severe chronic AR.

[Metabolism of myocardial catecholamines and plasma catecholamine levels in patients with chronic aortic regurgitation (author's transl)]. / Veränderungen des myokardialen Katecholamin-Stoffwechsels und Verhalten der Plasma-Katecholamine bei Patienten mit chronischer Aorteninsuffizienz.

In 17 patients suffering from severe chronic aortic regurgitation (class III N.Y.H.A.), during aortic valve replacement right atrial biopsies were taken. In these samples myocardial content of norepinephrine, normetanephrine, epinephrine and dopamine were determined. 2-4 days before valve replacement, plasma catecholamines were measured at rest and during isometric exercise. 15 patients with atrial septum defect (foramen secundum) served as controls. In patients with aortic regurgitation demonstrating no clinical signs of cardiac failure, myocardial content of norepinephrine, normetanephrine and epinephrine was significantly reduced compared to tissue content of patients with atrial septum defect. Right atrial content of dopamine did not reveal any difference between the two groups. In all patients, plasma catecholamines at rest were within normal limits. During isometric exercise, however, the increase of plasma norepinephrine in patients with aortic regurgitation was significantly higher compared to the control group. It is concluded from these data that patients with aortic regurgitation, demonstrating an exaggerated increase in sympathetic activity during exercise, probably show a decrease in myocardial norepinephrine tissue content. Therefore, clinical demonstration of hyperadrenergic response during exercise represents a simple metabolic parameter indicating alteration in myocardial metabolism in patients with chronic aortic incompetence. Since decision for aortic valve replacement should be done before irreversible damage of myocardium has established, it is supposed that assessment of sympathetic activity, at rest and during exercise, may reveal practical clinical importance.

[Effect of clonidine on plasma-catecholamine levels at rest and on ergometric exercise (author's transl)]. / Einfluss von Clonidin auf die Plasma-Katecholaminspiegel unter Ruhebedingungen und unter ergometrischer Belastung.

The effect of clonidine on peripheral venous-plasma catecholamine concentration was assessed in ten subjects with normal circulation, at rest and on submaximal bicycle exercise. Three hours after oral intake of 300 micrograms clonidine in single dose there was significant lowering of the plasma adrenaline and noradrenaline levels. Six hours after intake the lowest plasma catecholamine level was reached, but after 24 hours the clonidine effect had largely disappeared. The sympatholytic effect of clonidine was relatively less marked with bicycle exercise than at rest. When clonidine had been given for only a short period at moderate dosage, there was no exaggerated catecholamine rise. Clonidine administration did not effect plasma dopamine levels. These results indicate that clonidine decreases plasma adrenaline and noradrenaline levels without significant effect on circulatory regulation.