Showing papers by "Ronald L. Menlove published in 1988"

Changes in spontaneous variability of ventricular ectopic activity as a function of time in patients with chronic arrhythmias.

Abstract: Previous determinations of spontaneous variability in ventricular arrhythmia have often been based on measurements from consecutive days in small patient populations, whereas clinical determinations of drug efficacy typically compare measurements at intervals of 1 week and longer to baseline. We, therefore, sought to determine whether spontaneous arrhythmia variability changes as a function of time during periods ranging from 1 day to 1 year or longer. The percent reduction in the frequency of total premature ventricular complexes (PVCs) and repetitive ventricular beats required to show true drug effect rather than spontaneous variability in PVCs was determined in 47 consecutive patients with chronic ventricular arrhythmias who underwent multiple ambulatory monitor recordings while off active drug treatment (during placebo therapy). The variability in PVC rate was determined during the intervals of 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks, and 1 year or longer. The percent reductions in total PVCs required to exceed the 95% confidence limits of spontaneous variability at these intervals were 55%, 85%, 86%, 93%, 96%, and 96%, respectively. Corresponding values for repetitive beats were 75%, 95%, 92%, 95%, 94%, and 98%, respectively. The percent increase in total PVCs and repetitive beats required to establish "arrhythmia aggravation" caused by an antiarrhythmic drug with a 95% confidence limit also was calculated for this study population and was 124% and 303%, respectively, at 1-day intervals and 2,269% and 4,091%, respectively, at 1-year (or longer) intervals for the 24-hour monitor recordings. Variability was not substantially affected by underlying heart disease or ejection fraction. PVC rate showed a modest negative correlation with variability (r = 0.3). Thus, variability is substantially greater at 1 week, the usual time for clinical assessment of antiarrhythmic drug efficacy, than at 1 day (p less than 0.01). Suppression of more than 85% of total PVCs and more than 95% of repetitive beats appears to be necessary after 1-2 weeks to be confident of a true drug effect. Even greater variability is observed after 1 month and up to 1 year so that reductions of up to 95% in total PVCs and 98% in repetitive beats may represent spontaneous change.(ABSTRACT TRUNCATED AT 400 WORDS)

Dependence of assessment of coronary artery reperfusion during acute myocardial infarction on angiographic criteria and interobserver variability.

Abstract: The angiographic films of 240 patients with acute myocardial infarction were studied in a randomized trial of intravenous anisoylated plasminogen streptokinase activator complex (APSAC) versus intracoronary streptokinase therapies The interobserver variability of grading coronary artery perfusion by the Thrombolysis in Myocardial Infarction Study Group (TIMI) criteria was measured as well as the effect of different definitions of reperfusion on the determination of reperfusion rate There was good agreement in the reading of infarct artery flow grades between 2 blinded observers for each grade considered separately (k = 0726 +/- 0014) and for grades 0 or 1 (no perfusion) versus grades 2 or 3 (perfusion) (k = 0905 +/- 0011) Discordance between grades 0 or 1 versus 2 or 3 occurred in 74 (5%) of the 1,615 angiographic readings Discrepancies of clinical significance which affected qualification for study entry, reperfusion or reocclusion status occurred in only 15 patients (6%) Grade 1 flow was found to have the most variable interpretation Reperfusion rates for APSAC and streptokinase differed significantly when reperfusion was defined by 3 different criteria The reperfusion rate ranged from 51 to 72% for APSAC and from 60 to 75% for streptokinase depending upon criteria selected For comparison of the results of different thrombolytic studies, a standard semiquantitative system for grading infarct artery perfusion should be used, readings should be blinded and the criteria used for the definition of reperfusion should be clearly specified

The economic impact of DRG payment policies on air-evacuated trauma patients.

Abstract: This study assessed the injury severity, patient outcome, the cost of care, and the economic impact of Medicare DRG payment policies on patients referred to a Level I trauma center. Only 11 of 283 admitted traumatized patients were Medicare patients. Yet, these 11 Medicare patients left the trauma center with a deficit of $249,601. No significant differences were found between the Medicare and non-Medicare groups for Trauma Score, CRAMS Score, Glasgow Coma Score, Injury Severity Score, ICU or hospital length of stay, disability, or mortality. Under DRG's, Medicare payments ($4,237 +/- 2,351/patient) have fallen to 20% of prior cost-based Medicare reimbursements ($21,542 +/- 34,170/patient), are providing only 16% of hospital costs ($26,928 +/- 42,713/patient), and are significantly (p less than 0.0001) less than non-Medicare reimbursements ($15,288 +/- 17,111/patient). Despite the high financial losses occurring when the trauma center treats referred traumatized Medicare patients, when all referred Medicare and non-Medicare patient trauma reimbursements are combined, overall trauma revenues have declined by only 4.3% under DRG's. If Medicare DRG payments were to be adopted by all third-party payers, reimbursement ($5,058 +/- 4,090/patient) would be significantly (p less than 0.0001) less than current hospital reimbursements ($14,801 +/- 16,537/patient) and costs ($16,121 +/- 17,624/patient). These results indicate that although high financial losses result when caring for traumatized Medicare patients, DRG's have not had a major financial effect upon centers receiving referred trauma patients because of the low numbers of admitted traumatized Medicare patients. However, if third-party payers were to enact the Medicare payment system, devastating economic losses would be inflicted upon major trauma centers.

Effect of preoperative hemodynamic support on survival after cardiac transplantation.

Abstract: The accessibility and success of cardiac transplantation promotes transplantation for a broad range of recipients, including those requiring intravenous inotropes or mechanical-assist devices. To determine if survival is dependent on preoperative requirements for hemodynamic support, we studied 230 patients who underwent transplant at the Loyola, Stanford, and UTAH programs from December 1, 1984 through November 30, 1986, and who were followed up for 34 months postoperatively. Group 1 (n = 132 of 230, 57%) patients required only oral medical therapy to maintain hemodynamic compensation; Group 2 (n = 69 of 230, 30%) patients were dependent on intravenous inotropic support; and Group 3 (n = 29 of 230, 13%) patients required mechanical assistance. Pretransplant characteristics showed that dilated cardiomyopathy was more common in Group 2 patients, and lower cardiac index and ejection fraction were more prevalent in Group 3 patients as expected. Although survival was lower in Group 3 only at 1 month (Group 1, 98.5%; Group 2, 92.8%; and Group 3, 86.2%; p less than 0.01), the survival advantage in Groups 1 and 2 was lost by 3 months, with 1-year survival rates of 88.6% in Group 1, 81.2% in Group 2, and 82.8% in Group 3. Allograft survival and cause of death were not different among the three groups. Acute rejection occurred at a lower monthly frequency in the first 4 months in Group 3 (Group 1, 0.47 +/- 0.03; Group 2, 0.47 +/- 0.05; and Group 3, 0.29 +/- 0.06; p less than 0.01), whereas infectious complications occurred at similar frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunofluorescence Microscopy in the Diagnosis and Follow-up of Patients Suspected of Having Inflammatory Heart Disease

Abstract: In a previously published study, we showed that immunofluorescence (IF) microscopy can help to distiguish myocarditis from idiopathic dilated cardiomyopathy [1]. However, since the previous study was relatively small, consisting only of 79 patients, an evaluation of differing patterns of IF staining as well as serial changes in patients biopsied on several occasions were not reported. We now report our findings in an expanded series of 286 endomyocardial biopsies (208 patients) which were prospectively examined by light and IF microscopy. Our findings suggest that IF microscopy is a complementary technique which serves to define better the presence and type of inflammatory heart disease found in such patients.