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P Satter

Publications and source records attributed to P Satter.

133 records · Page 8Linked to original sources
PubMedDate not supplied

Endothelium-dependent and endothelium-independent flow regulation in coronary vascular regions supplied by arterial and venous bypass grafts.

The endothelium-dependent and endothelium-independent vasodilation of arterial and venous coronary bypass grafts and of epicardial conduit vessels and microcirculatory coronary vessels supplied by these grafts was investigated. Vasodilatory response and flow regulation were tested with cumulative intracoronary doses of acetylcholine (25 and 50 micrograms i.c.), nitroglycerin (0.3 mg i.c.), and papaverine (10 mg i.c.) in 10 patients (age 60 +/- 2.3 years) with arterial grafts and in 16 patients (age 57.7 +/- 1.5 years) with venous grafts. The effect of acetylcholine on arterial and venous bypass grafts and on large conduit arteries was evaluated by quantitative coronary angiography. Coronary blood flow velocity changes as a parameter of microcirculatory function were measured by intraluminal Doppler ultrasound. Indices for coronary flow and coronary resistance were calculated from the mean Doppler flow velocity and the computed cross-sectional vascular area. The coronary resistance decreased endothelium dependent after 25 and 50 micrograms of acetylcholine by 16 +/- 30% (p < 0.05 vs. control) and 22 +/- 25% (p < 0.05 vs. control), respectively, in regions supplied by venous grafts and by 48 +/- 20% (p < 0.05 vs. control and vs. venous graft) and 41 +/- 32% (p < 0.05 vs. control), respectively, in regions supplied by arterial grafts. The coronary resistance decreased endothelium independent after 0.3 mg nitroglycerin and 10 mg papaverine by 18 +/- 56% (p < 0.05 vs. control) and 39 +/- 29% (p < 0.05 vs. control), respectively in regions supplied by venous grafts and by 45 +/- 45% (p < 0.05 vs. control) and 70 +/- 12% (p < 0.05 vs. control and vs. venous graft), respectively in regions supplied by arterial grafts. In conclusion, during the long-term course after coronary artery bypass grafting, vascular regions supplied by arterial grafts have a better preserved endothelium-dependent and endothelium-independent flow reserve as compared with vascular regions supplied by venous grafts.

Acetylcholine↗
PubMedDate not supplied

New surgical treatment for severe limb ischemia.

Revascularization after prolonged complete limb ischemia may result in severe damage to skeletal muscle and systemic alterations (postischemic syndrome). Our previous experimental studies have shown that this injury can be reduced substantially by treating the jeopardized extremity by controlling the conditions of reperfusion and composition of the initial reperfusate. In the present study this concept of controlled limb reperfusion was applied in patients with prolonged severe limb ischemia. Controlled limb reperfusion was used in 14 patients after prolonged complete uni- or bilateral ischemia. The ischemic interval ranged from 5 to 21 h. Two patients were in cardiogenic shock, 11 had associated cardiac disease, and seven coexistent peripheral vascular disease. After systemic heparinization, standard thromboembolectomy was done using a Fogarty catheter. Cannulas were placed into the iliac, profunda, and superficial femoral arteries and were connected to a reperfusion set. Oxygenated blood was drawn from the iliac artery and mixed with an asanguineous solution (ratio 6:1). This controlled reperfusate was delivered into the profunda and superficial femoral arteries using a single rollerpump. The system allows control of the composition of the reperfusate (calcium, pH, osmolarity, glucose, substrate, pO2, free radical scavengers) and the conditions of reperfusion (pressure, flow, temperature). After 30 min of controlled limb reperfusion, the cannulas were removed and normal blood reperfusion started. All 12 patients who were stable hemodynamically before the operation survived the revascularization. Eleven patients, including one with acute aortic occlusion for several hours, were discharged with functional recovery of their extremities. Despite the severe ischemic insult, controlled limb reperfusion avoided amputation and profound systemic complications. Two patients who were in cardiogenic shock preoperatively died from progressive cardiac failure. We conclude that controlled arterioarterial limb reperfusion may reduce the local manifestations of the postischemic syndrome after prolonged periods of ischemia, may salvage limbs thought previously to be damaged irreversibly by prolonged ischemia, and can be done easily in the operating room.

Adult↗
PubMedDate not supplied

Studies of reperfusion injury in skeletal muscle: preserved cellular viability after extended periods of warm ischemia.

Four hours of complete normothermic ischemia in the rat hindlimb has been thought to produce extensive and irreversible damage and no possibility of salvage by reperfusion. This study tests the hypothesis that, in contrast to conventional wisdom, the cellular integrity is preserved after 4 hours of complete warm ischemia and control of the initial reperfusion can restore immediate contractility in these limbs. Ninety-two rat hindlimbs were isolated and 26 of the 92 did not undergo ischemia or reperfusion and served as controls. Sixty-six limbs were subjected to 4 hours of complete warm ischemia; of those 34 were assessed after the ischemic period without reperfusion and 32 were reperfused after the ischemic period. Nineteen hindlimbs were reperfused with Krebs-Henseleit buffer at a pressure of 100 mmHg to simulate embolectomy (uncontrolled reperfusion). In 13 legs a modified reperfusate at a pressure of 60 mmHg was used during the initial 30 minutes followed by an additional 30 minutes of reperfusion with 100 mmHg using Krebs-Henseleit buffer (controlled reperfusion). At the end of each experimental protocol, limbs were assessed by the following methods: muscle contraction, water content, volume, high energy phosphate content, muscle pH, effluent pH, mitochondrial function, ultrastructure, flow, and creatinkinase activity in the effluent. Data are expressed as mean +/- SEM. Significant differences were defined as probabilities for each test of p less than 0.05. Four hours of complete warm ischemia resulted in a severe reduction of adenosine triphosphate (4.0 +/- 0.8 vs 27.1 +/- 6.7 mumol/gm protein, p less than 0.001) and no contractions could be stimulated (0.0 +/- 0.0% CC). Muscle pH fell to 6.3 +/- 0.1 (p less than 0.001), and ultrastructural damage occurred (score 3.3 +/- 0.4 vs 0.8 +/- 0.1, p less than 0.002). However, there was only a slight increase in water content of the soleus muscle (78.7 +/- 0.2% vs 74.8 +/- 1.1%, p less than 0.05) without increase in limb volume (103.6 +/- 0.6% CV). In addition mitochondrial function was preserved well: mitochondrial oxidative phosphorylation capacity remained at 94% of control levels, ST3 at 93%, and ADP/O at 100% of control. Most importantly, controlled reperfusion restored immediate contractility in all limbs and was superior in all parameters investigated compared to uncontrolled reperfusion. These data support our inference that necrosis of skeletal muscle does not invariably occur after four hours of complete warm ischemia and suggest that muscle salvage by controlled reperfusion is possible after at least 4 hours of warm ischemia.

Adenosine Triphosphate↗
PubMedDate not supplied

Early and long term results of cardiac surgery in dialysis patients.

OBJECTIVES: The risk of cardiac surgery in dialysis patients is increased compared with other patient groups. We analyzed early and long term results following various cardiac procedures. METHODS: Between 1981 and 1992, 40 patients underwent cardiac surgery with a mean age of 55.7-years (range 31-71 years). Cardiac procedures: Coronary artery bypass grafting (CABG) n = 20, aortic valve replacement (AVR) n = 6, mitral valve replacement (MVR) n = 4, AVR+CABG n = 1, MVR+CABG n = 1, AVR+MVR n = 2, combined heart and renal transplantation n = 2, atrial septal defect-closure n = 1, pericardial decortication n = 3. The preoperative NYHA functional classes were: NYHA II 5%, III 52.2%, IV 42.5%. Operative mortality was 15% (6/40). Hospital survivors were in NYHA functional classes I (3%), II (88.2%) and III (8.8%). A follow-up study was performed at 35 months (mean, range 1-93 months) postoperatively. RESULTS: There were 11 late deaths. The actuarial survival of all patients was 91% (1 year) and 69% (5 years). Following CABG it was 95% (1 year) and 72% (5 years). Survivors were in NYHA functional classes I 4.7%, II 85.8%, III 9.5%. CONCLUSION: Cardiac surgery in dialysis patients is associated with an acceptable hospital mortality. The quality of life of long term survivors is increased significantly. Thus we advocate surgical treatment in patients with symptomatic heart disease. Early diagnosis and surgical intervention in the NYHA functional class II may lead to a lower perioperative mortality.

Adult↗