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Anemia and renal insufficiency impart an increased risk of mortality in patients with congestive heart failure. There is a paucity of data on the mortality hazard associated with anemia and renal insufficiency in patients undergoing percutaneous coronary intervention in the setting of contemporary practice. We analyzed the short- and long-term outcomes among patients enrolled in EPIC, EPILOG and EPISTENT trials according to degree of kidney dysfunction (glomerular filtration rate [GFR] <60, 60 to 75, and >75 ml/min/1.73 m2) and by hematocrit (<35, 35 to 39 and 40). GFR was calculated as GFR = 186 x (serum creatinine-1.154) x (age-0.203) x 1.212 (if black) or x 0.742 (if female). There were 20 deaths (3.2%) among 638 patients with a hematocrit of <35, 41 deaths among 2,066 patients (2.0%) with a hematocrit of 35 to 39, and 43 deaths in 3,618 patients (1.2%) with a hematocrit >40 at 6 months (p <0.001). Similarly, a significant increase in mortality was seen with lower GFR [33 of 1,168 (2.9%) at GFR <60, 33 of 1,766 (1.9%) at GFR 60 to 75 and 37 of 3,317 (1.1%) at GFR >75, p <0.001)]. Further, GFR and anemia independently and in combination predicted mortality at 3 years. Thus, renal insufficiency and anemia are significant independent and additive predictors of short- and long-term complications in patients undergoing percutaneous coronary intervention.  相似文献   
154.
The effect of the vasodilator prazosin vs placebo on exercise duration until marked dyspnea, and on left ventricular function measured by echocardiography, was evaluated in a double-blind, randomized study in 24 patients with chronic left ventricular failure despite digitalis and diuretic therapy. Compared with the double-blind placebo, prazosin reduced resting systolic and diastolic blood pressure and systolic blood pressure times heart rate, improved clinical symptoms, decreased cardiothoracic ratio measured by chest roentgenography, decreased left ventricular and left atrial dimensions, improved ejection fraction and Vcf measured by echocardiography, and improved treadmill exercise duration. All 12 patients taking prazosin had greater than or equal to 20% improved treadmill exercise duration; none of 12 receiving placebo improved. In six of 12 patients taking prazosin, roentgenographic evidence of pulmonary venous congestion disappeared compared with none of the patients on placebo. These data suggest that prazosin may be effective in treating chronic left ventricular failure.  相似文献   
155.
W S Aronow  J Cassidy 《Circulation》1975,52(4):616-618
The double Master's test, the maximal treadmill stress test, the resting apexcardiogram, and the postexercise apexcardiogram significantly correlated with the development of subsequent coronary heart disease within five years in 100 asymptomatic persons. The maximal treadmill stress test correlated better than the double Master's test in predicting subsequent coronary heart disease. The presence of both an abnormal maximal treadmill stress and an abnormal a-wave ratio in the postexercise apexcardiogram had the best value in predicting subsequent coronary heart disease.  相似文献   
156.
We evaluated the relationship of S1 recorded by phonocardiography at the mitral area with motion of the mitral, tricuspid, and aortic valves, recorded by simultaneous echocardiography in 20 cardiac patients with a normal PR interval. The first major component of S1 coincided with mitral valve closure in 20 of 20 patients (100%) and also with tricuspid valve closure in 14 of 20 patients (70%). The second major component of S1 coincided with aortic valve opening in 20 of 20 patients and also with tricuspid valve closure in six of 20 patients (30%). We conclude that the first major component of S1 coincides with mitral valve closure in all patients but may also coincide with tricuspid valve closure in many patients, and the second major component of S1 coincides with aortic valve opening in all patients but may also coincide with tricuspid valve closure in some patients.  相似文献   
157.
Coronary risk factors should be modified in older persons after myocardial infarction (MI). Aspirin 160–325 mg daily and β blockers should be administered indefinitely. Anticoagulants should be administered post-MI to patients unable to tolerate daily aspirin, to those with persistent atrial fibrillation, and to those with left ventricular thrombus. Nitrates, along with βblockers, should be used to treat angina pectoris. Angiotensin-converting enzyme inhibitors should be administered after MI to patients who have congestive heart failure, an anterior MI, or a left ventricular ejection fraction of =40%. There are no class I indications for the use of calcium channel blockers after MI. Complex ventricular arrhythmias should be treated with βblockers. Persons with life-threatening ventricular tachycardia or ventricular fibrillation or who are at very high risk for sudden cardiac death after MI should receive an automatic implantable cardioverter-defibrillator. There are no class I indications for the use of hormonal therapy in postmenopausal women after MI. Indications for coronary revascularization after MI in older individuals are prolongation of life and relief of unacceptable symptoms despite optimal medical management.  相似文献   
158.
Ivy  SP; Olshefski  RS; Taylor  BJ; Patel  KM; Reaman  GH 《Blood》1996,88(1):309-318
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents.  相似文献   
159.
In this retrospective follow-up study, the authors examined the association between race and the receipt of cardiology care in 1062 Medicare beneficiaries 65 years of age and older who were hospitalized with heart failure. The primary outcome measure was receipt of care from a cardiologist (via admission or consultation). Using logistic regression analyses, crude and adjusted odds ratios (OR) and 95% confidence intervals (95%CI) of receipt of cardiology care were estimated for nonwhite versus white patients. Two hundred (19%) patients were nonwhites and 483 (46%) patients received care from cardiologists. Proportion of patients receiving cardiology care was lower among nonwhite patients (35% versus 48% among whites; P = 0.001), and nonwhite race was associated with a lower odds of receiving cardiology care (crude OR = 0.57; 95%CI = 0.42-0.79). After adjustment for various patient characteristics and process-of-care variables, the magnitude and precision of the association between nonwhite race and a lower odds of receiving care from a cardiologist remained unchanged (adjusted OR = 0.43; 95% CI = 0.30-0.62). These findings suggest that nonwhite elderly hospitalized heart failure patients are less likely to be cared for by cardiologists.  相似文献   
160.
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