ABSTRACT
Nearly forty years ago, Swan and Ganz introduced pulmonary artery catheterization to monitor the hemodynamic status of critical patients. The need for pulmonary artery catheterization in clinical practice has been questioned because it may be related to increased mortality and because alternative techniques that will probably cause less morbidity and mortality have been developed. The introduction of color Doppler echocardiography has been fundamental in the hemodynamic and etiologic evaluation of critical patients and has made it possible to clarify many clinical situations in which the response to treatment was unacceptable. This review aims to discuss the advantages and drawbacks of the Swan-Ganz catheter as the gold standard for monitoring hemodynamics in critical patients. We believe that combining the available techniques should help us evaluate the hemodynamics in critical patients and determine the cause of hemodynamic instability so we can select the most appropriate initial treatment and evaluate the subsequent response.
Subject(s)
Catheterization, Swan-Ganz , Cardiac Output , HumansABSTRACT
BACKGROUND: Sustained ventricular tachycardia (VT) complicating the acute phase of myocardial infarction (AMI) is a quite rare event but with short-term unfavorable prognosis. The clinical characteristics as well as the therapeutic implications have not yet been well defined. HYPOTHESIS: This paper attempts to prove that VT may be considered a marker of inadequate myocardial perfusion after thrombolysis. METHODS: To assess the clinic-electroangiographic characteristics and prognosis of patients with VT occurring within the first 4 days of an AMI, a case-control study was carried out in 23 patients from a total of 1,100 patients (1.9%) hospitalized with AMI between March 1993 and July 1997. These patients were compared with a control group of 131 patients hospitalized consecutively. A statistical analysis was made using the chi-square test, t-test, and logistic regression. RESULTS: There were no differences among groups with regard to age, gender, and area of necrosis. Average time for the onset of VT was 26 h (range 0-92 h). Sixteen patients underwent coronary angiography: 4 patients had left main coronary artery disease, 2 had single-vessel disease, 8 had lesions in two vessels, and 2 had triple-vessel disease. Univariate analysis showed that patients with VT had a higher incidence of creatine phosphokinase (CPK)-MB peak > 300 UI/l (61 vs. 30%; p<0.001), more frequent occurrence of previous AMI (48 vs. 17%; p<0.001), and acute intraventricular conduction disorders (26 vs. 4%; p<0.001). Furthermore, these patients suffered ischemia previous to VT more frequently (65 vs. 11%; p<0.0001), and had a greater mortality rate than that in the control group (35 vs. 4%; p<0.0001). In the multivariant analysis, the variables related to the occurrence of VT were CPK-MB peak > 300 IU/l (OR 5.9; 95% CI 1.6-21), acute intraventricular conduction disorders (OR 9.02; 95% CI 1.7-48), and ischemia immediately prior to VT (odds ratio [OR] 19.64; 95% confidence interval [CI] 5.3-73). CONCLUSIONS: Ventricular tachycardia may be considered a marker of inadequate myocardial perfusion after thrombolysis; therefore, a more aggressive revascularization treatment in these patients would be advisable. The profile of patients with AMI, hospitalized in the coronary care unit, who will likely suffer from VT is previous AMI, CPK-MB peak > 300, acute intraventricular conduction disorders, Killip > I, and ischemia previous to VT.
