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101.
102.
The initial surgical attempts to treat atrial fibrillation (AF) were isolation procedures designed to confine the arrhythmia to a specific area of the heart for relief of symptoms. The first surgical attempt to ablate AF was unsuccessful but was quickly followed by the Maze-I procedure on September 25, 1987. Because of several adverse sequelae of the Maze-I procedure, it was sequentially modified to the Maze-II and then Maze-III procedures. The Maze-IV procedure was introduced some 10 years later; these are the only 4 procedures that adhere to the concept of a maze pattern of lesions to ablate AF and leave both atria capable of being activated during normal sinus rhythm. The term maze procedure has become generic for virtually any operation designed to treat AF, but procedures that do not adhere to the concept of creating lesions of conduction block in the pattern of a maze are not maze procedures. These include, among others, the Wolf Mini-Maze, the Left-Sided Maze, and the 5-Box Maze, none of which are truly based on the maze-pattern concept. The cardinal feature of maze procedures that is necessary for both effectiveness and comparability to classical maze procedures includes lines of conduction block that preclude macro-reentry anywhere in either atrium while leaving both atria capable of activation by a sinus-generated impulse. Components essential to achieving this include appropriate lesions in both atria, the absence of gaps that allow electrical activity to bypass an intended line of block, and the absence of alternate pathways by which impulses can reach the intended maze exit.  相似文献   
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This study compares left ventricular (LV) performance during exercise in patients with angiographically documented coronary artery disease (CAD) based on the presence or absence of angina pectoris during the index exercise tests. The patients were divided into 2 groups: Group I included 31 patients who had angina pectoris during the test and Group II included 43 who did not. Multivessel CAD was present in 21 patients (68%) in Group I and 26 patients (60%) in Group II (difference not significant [NS]). There were no significant differences between the 2 groups in age, sex, history of diabetes mellitus, history of myocardial infarction and in the exercise duration, work load, heart rate and systolic blood pressure. Exercise-induced ST-segment depression was present in 48% of the patients in Group I and in 40% in Group II (NS). The mean LV ejection fraction at rest was 52 ± 12% in Group I and 50 ± 17% in Group II (NS). There were significant differences in the 2 groups in the change from rest to exercise in ejection fraction (?4.5 ± 7.6% in Group I vs 1 ± 9.4% in Group II, p < 0.01), end-systolic volume (29 ± 38 ml in Group I vs 9 ± 23 ml in Group II, p < 0.005), the change in systolic blood pressure-to-end-systolic volume ratio (?0.1 ± 0.5 mm Hg/ml in Group I vs 0.3 ± 1.1 mm Hg/ml in Group II, p < 0.05), and wall motion score (?0.4 ± 0.6 in Group I vs 0.09 ± 0.7 in Group II, p < 0.05).Thus, asymptomatic myocardial ischemia may occur in patients with extensive CAD and be associated with abnormal exercise LV function; however, patients with symptomatic CAD have worse exercise LV function than those with asymptomatic CAD.  相似文献   
106.
Forearm glucose uptake (FGU) and other metabolic responses were studied in six normal men for three hours after a 75-g oral glucose load and a mixed meal containing 75 g carbohydrate. After the meal the rise in arterial glucose levels was considerably less than that following the oral glucose load but the overall insulin responses from 0 to 180 minutes were not statistically different. Although the initial rise in FGU was more gradual after the meal, the subsequent elevation was more sustained and, at the termination of the study, exceeded significantly that seen after the oral glucose load. The rise in GIP levels during the first hour was similar after the meal and the oral glucose load, but thereafter concentrations following the oral glucose load fell while those after the meal continued to rise. When the incremental area (delta) is used as the index of response, the results show that while the glucose response (delta G) after the meal (19.1 +/- 5.3 units) was only 26% of that after oral glucose loading (72.7 +/- 7.0 units), the corresponding increase in FGU (delta FGU) reached 62% (55.0 +/- 12.8 units after the meal, 89.2 +/- 20.0 units after the oral glucose load). Thus, the increase in peripheral glucose uptake relative to the glycemic response (delta FGU/delta G) was significantly greater after the meal than following the oral glucose load alone (P less than 0.05). In conclusion, relative to the rise in arterial glucose levels, peripheral glucose uptake is greater after a meal than after glucose loading with an equivalent carbohydrate challenge. Furthermore, the present data support previous studies emphasizing the failure of GIP alone to explain the entero insular axis.  相似文献   
107.
The hospital records of 264 patients with 277 episodes of pneumococcal bacteremia occurring at New York Hospital-Cornell Medical Center over the period 1970 to 1980 were examined to determine whether serotype distribution varied with the underlying disease or age of the patient. The patients were placed into three groups according to their underlying disease. Group A consisted of all patients with significant impairment of their immune system. Group B included those patients with underlying conditions that were not associated with immune deficiency. Group C comprised those patients considered to be normal hosts. Overall, 84 percent of blood isolates were serotypes included in the vaccine. In Group A, only 73 percent of these isolates were vaccine types, compared with 85 percent in Group B and 97 percent in Group C (differences significant at p < 0.001). Vaccine serotypes were more common in children than adults (92 versus 81 percent), but in analysis that controlled for underlying disease, the elderly did not differ from younger adults in serotype distribution. The apparent predilection of nonvaccine serotypes to cause bacteremia in immunocompromised patients may be one factor limiting vaccine efficacy in this high-risk population.  相似文献   
108.
To assess the efficacy, plasma drug concentrations and adverse effects of a new sustained release preparation of procainamlde, 33 patients with heart disease were studied in an acute dose-ranging protocol and a chronic treatment protocol. Patients initially received a daily dose of 3 g of sustained release procainamide; this dose was increased by 1.5 g daily until ventricular premature depolarizations were suppressed by 75 percent or more, adverse drug effects occurred or a total daily dose of 7.5 g of sustained-release procainamide was reached. Twenty-five patients (76 percent) had at least a 75 percent reduction (range 75 to 100 percent [mean ± standard deviation 91 ± 8.2]) in ventricular premature depolarization frequency at a dosage of 4.8 ± 1.46 g/day (range 3.0 to 7.5). Despite the 8 hour dosing interval, the variation between maximal and minimal plasma procainamide and N-acetylprocainamide concentrations under steady state conditions was very small. Mean maximal procainamide and N-acetylprocainamide plasma concentrations were 10.4 +- 6.02 and 12.0 ± 7.40 μg/ml, respectively. The respective mean minimal concentrations were 6.8 ± 4.50 and 8.7 ± 5.99 μg/ml In nine patients (27 percent) treatment with sustained release procainamide resulted in conversion of the antinuclear antibody test from negative to positive. Adverse drug effects occurred in 17 (52 percent) of the subjects. In general, adverse effects were minor and abated within 24 hours after administration of the drug was stopped. One patient had the procainamide-induced systemic lupus erythematosus-like syndrome.  相似文献   
109.

Background

Although used as criterion for early drain removal, postoperative day (POD) 1 drain fluid amylase (DFA) ≤ 5000 U/L has low negative predictive value for clinically relevant postoperative pancreatic fistula (CR-POPF). It was hypothesized that POD3 DFA ≤ 350 could provide further information to guide early drain removal.

Methods

Data from a pancreas surgery consortium database for pancreatoduodenectomy and distal pancreatectomy patients were analyzed retrospectively. Those patients without drains or POD 1 and 3 DFA data were excluded. Patients with POD1 DFA ≤ 5000 were divided into groups based on POD3 DFA: Group A (≤350) and Group B (>350). Operative characteristics and 60-day outcomes were compared using chi-square test.

Results

Among 687 patients in the database, all data were available for 380. Fifty-five (14.5%) had a POD1 DFA > 5000. Among 325 with POD1 DFA ≤ 5000, 254 (78.2%) were in Group A and 71 (21.8%) in Group B. Complications (35 (49.3%) vs 87 (34.4%); p = 0.021) and CR-POPF (13 (18.3%) vs 10 (3.9%); p < 0.001) were more frequent in Group B.

Conclusions

In patients with POD1 DFA ≤ 5000, POD3 DFA ≤ 350 may be a practical test to guide safe early drain removal. Further prospective testing may be useful.  相似文献   
110.
Pulmonary perfusion scintiphotographs in patients with acute, extensive pulmonary embolism have disclosed instances in which Scintiphotographic changes thought to indicate embolic recurrence were not substantiated by clinical-angiographic observations. These spurious Scintiphotographic recurrences reflected changes in the regional distribution of pulmonary vascular resistance secondary to different rates of embolic resolution or distal migration of emboli. To document the influence of changes in vascular resistance upon perfusion scintiphotographs, studies were performed in animals subjected to various sequences of pulmonary arterial obstruction by balloon catheters. Scintiphotographic changes mimicking, but not representing, recurrence of embolism were produced. Observations in both animals and man indicate that the diagnosis of embolic recurrence based on Scintiphotographic changes alone should be made with caution, particularly in patients with multiple emboli and pulmonary hypertension.  相似文献   
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