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Y Agmon

Publications and source records attributed to Y Agmon.

28 records · Page 2Linked to original sources

Single physician approach to radiofrequency catheter ablation in patients with supraventricular tachycardia.

The minimal requirements for safe and effective performance of catheter ablation using radiofrequency current are still unclear. To determine the feasibility and safety of single physician approach to catheter ablation of supraventricular tachycardia substrate using radiofrequency energy, the results of the ablation procedure in 52 consecutive patients were evaluated. The procedures were performed during 1 year by the same physician and nurse. Twenty-one patients had selective atrioventricular (AV) nodal pathway ablation and 31 patients had accessory AV pathway ablation. Forty-eight patients (89%) had the diagnostic and the ablative procedure during the same electrophysiological test. In the 21 patients with AV nodal reentrant tachycardia, all had successful selective ablation of the fast (13) or the slow (8) pathways. Eight patients had recurrence of the clinical tachycardia and had a successful reablation. No patient developed complete AV block or other significant complications. The mean fluoroscopy time during the procedure was 16.0 +/- 8.6 minutes. In the eight patients with Wolff-Parkinson-White syndrome, all concealed accessory pathways were successfully ablated with a mean fluoroscopy time of 30.0 +/- 27.9 minutes. Two patients had recurrence of the conduction through the accessory pathway and had a successful reablation. Eighteen of 19 patients with a single overt accessory pathway had successful ablation, with a fluoroscopy time of 22.7 +/- 20.6 minutes. Three patients had an early recurrence of the conduction through the accessory pathway, reablation was successful in two of them. Ten accessory pathways were ablated in four patients with multiple pathways during nine procedures. Only two patients developed minor peripheral vascular complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Disparate effects of adenosine A1- and A2-receptor agonists on intrarenal blood flow.

Endogenous adenosine, secreted locally by the kidney during tissue hypoxia, induces heterogeneous renal hemodynamic responses. We investigated the cortical and outer medullary blood flow responses to intrarenal infusions of adenosine and adenosine A1- and A2-receptor agonists in anesthetized rats. These agents were infused into the renal interstitium through chronically implanted capsules, and blood flow was measured by laser-Doppler probes. Short (1 min, 0.05 ml) intrarenal infusions of adenosine (0.5 mumol) lowered cortical blood flow to 27 +/- 10% of baseline (n = 7, P < 0.0005). Medullary blood flow response was biphasic, i.e., a transient decrease in flow to 52 +/- 8% of baseline (n = 17, P < 0.0001) followed by a more-sustained increase in flow to 135 +/- 6% (n = 17, P < 0.0001). N6-cyclopentyladenosine, an adenosine receptor A1 agonist, reduced both cortical and medullary blood flow to 59 +/- 4% (n = 10, P < 0.0001) and 38 +/- 5% (n = 11, P < 0.0001) of baseline, respectively. By contrast, 2-[p- (carboxyethyl)phenethylamino]-5'-N-ethycarboxamidoadenosine (CGS-21680C), an adenosine receptor A2 agonist, increased dramatically the medullary blood flow to 184 +/- 15% of baseline (n = 12, P < 0.0005), without major changes in cortical flow. We conclude that intrarenal adenosine reduces cortical blood flow and predominantly increases medullary flow via A1 and A2 receptors, respectively. These hemodynamic responses could play a role in protection of the outer medulla from hypoxia.

Adenosine↗

Acute renal failure: a multifactorial syndrome. Pathogenesis and prevention strategies.

Professor Geoffrey M. Berlyne has devoted many years of his productive life to improve our understanding of kidney physiopathology and to enhance our treatment modalities for renal failure. This review of acute renal failure, with emphasis on some recent progress in our understanding of this syndrome, is dedicated to honor Professor Berlyne's 60th birthday.

Acute Kidney Injury↗

Effects of nonsteroidal anti-inflammatory drugs upon intrarenal blood flow: selective medullary hypoperfusion.

Nonsteroidal anti-inflammatory drugs (NSAIDs) predispose to acute and chronic renal failure, possibly due to intrarenal hemodynamic effects. In anesthetized volume-expanded rats, total renal blood flow (RBF) was measured by an ultrasonic flowmeter placed around the left renal artery, superficial cortical blood flow (sCBF) by a flunt laser-Doppler probe placed over the kidney surface, mid-cortical (mCBF) and outer medullary blood flow (oMBF) by a needle laser-Doppler probe inserted into the renal parenchyma. Indomethacin (5 mg/kg i.v.) caused no significant change in RBF (n = 9) or mCBF (n = 6) and slightly increased sCBF (to 106 +/- 2% of baseline; n = 8, p < 0.05). By contrast, oMBF dropped significantly (to 55 +/- 4% of baseline; n = 8, p < 0.0001) within 30 min of indomethacin administration. Similarly, acetylsalicylate (50 mg/kg i.v.) slightly increased sCBF (to 110 +/- 3% of baseline; n = 5, p < 0.05) but caused a significant drop in oMBF (to 54 +/- 2% of baseline; n = 5, p < 0.0001). These results suggest that NSAIDs cause a profound and selective reduction in oMBF which may predispose to acute or chronic intrarenal damage by aggravating medullary hypoxia.

Animals↗