Benefits obtained by the introduction of a coronary-care unit. A comparative study

Red cell distribution width is correlated with all-cause mortality of patients in the coronary care unit

Objective

The predictive value of red blood cell distribution width (RDW) in patients in the coronary care unit (CCU) remains unknown. This study aimed to examine the prognostic value of RDW in these patients.

Methods

Clinical data were extracted from the Medical Information Mart for Intensive Care-III database. Baseline data were collected within 24 hours after patients’ first admission to the CCU. The outcomes of our study were 30-day and 90-day mortality.

Results

A total of 8254 patients were included and their mean age was 66.9 ± 15.8 years (56% were men). For 30-day all-cause mortality, the hazard ratios (95% confidence interval) of the medium RDW (13.7–15.3) and high-RDW groups > 15.3) were 1.72 (1.55, 1.91) and 2.57 (2.33, 2.85), respectively, compared with the reference group in an unadjusted model. This association remained similar in multivariate models. Similar correlations were observed for 90-day all-cause mortality. The areas under the curve of RDW and the Sequential Organ Failure Assessment (SOFA) score were 0.625 and 0.692, respectively.

Conclusions

RDW is correlated with an increased risk of 30-day and 90-day mortality of patients in the CCU. The predictive value of RDW is not as good as that of the SOFA score.

Evolution of the coronary care unit: clinical characteristics and temporal trends in healthcare delivery and outcomes

OBJECTIVE

To describe long-term temporal trends in patient characteristics, processes of care, and in-hospital outcomes among unselected admissions within the contemporary coronary care unit.

DESIGN

Hospital administrative database that records both payment and operation data.

SETTING

Coronary care unit of a large, academic, tertiary-care medical institution.

PATIENTS

A total of 29,275 patients admitted from January 1, 1989 through December 31, 2006.

INTERVENTIONS

Unadjusted time-trend plots were created for all variables of interest, and multivariable modeling of coronary care unit death was performed.

MEASUREMENTS AND MAIN RESULTS

Temporal trends in Coronary Care Unit and in-hospital mortality, length-of-stay, demographic characteristics, discharge diagnoses, Coronary Care Unit procedures, and Charlson comorbidity scores were evaluated. Admission severity increased significantly over time (p < .001), but hospital length-of-stay decreased (p < .001). The proportion of coronary care unit admissions with non-ST-segment elevation myocardial infarction increased (p < .001), whereas ST-segment elevation myocardial infarction decreased (p < .001). The prevalence of non-cardiovascular diagnoses increased, with the rate greatest for comorbid critical illnesses, including sepsis, acute kidney injury, and respiratory failure (all p < .001). The use of non-cardiac procedures, such as mechanical ventilation and central venous catheterization, also increased over time (p < .001). Unadjusted coronary care unit and in-hospital mortality did not change during the study period, although death did decrease in the adjusted setting.

CONCLUSIONS

Substantial changes have occurred over time in patient characteristics, diagnoses, and procedures within the coronary care unit of a large, academic medical center. In particular, there have been significant increases in noncardiovascular critical illness, the results of which may be influencing patient outcomes. These findings underscore an existing need to clarify the role of the coronary care unit in contemporary cardiovascular care and to develop strategies for optimal training, staffing, and clinical investigation.

Prognosis after acute myocardial infarction continues to improve in the reperfusion era in the community of Göteborg

BACKGROUND

The objective of this study was to compare the prognosis of nonselected patients who had an acute myocardial infarction (AMI) during 2 time periods in the thrombolytic era and to describe coronary heart disease (CHD) mortality rates in the community of Göteborg during 1990 to 1995.

METHODS

Patients aged <75 years who were hospitalized in the community of Göteborg for AMI during 1990 to 1991 (period 1) and 1995 to 1996 (period 2) were compared in terms of history, treatment for AMI, and outcome. Information on CHD mortality rates in the community of Göteborg was gathered from the National Registry of Deaths.

RESULTS

The numbers of patients in the 2 cohorts were 926 and 861, respectively. The incidence rate for AMI per 100,000 inhabitants and year was 200 for period 1 and 183 during period 2. During period 2, there was an increased use of percutaneous transluminal coronary angioplasty, coronary artery bypass grafting, angiotensin-converting enzyme inhibitors, heparin, and intravenous nitroglycerin. On the other hand, there was a decreased use of thrombolytic agents, diuretic agents, digitalis, long-acting nitrates, calcium-channel blockers, and lidocaine. The hospital case-fatality rates were 9.4% during period 1 and 6.0% during period 2 (P =.01). The adjusted risk ratio for period 2 versus period 1 was 0.65, with 95% confidence limits of 0.45 to 0.94. The mortality rate over a period of 3 years was 26.5% during period 1 and 17.8% during period 2 (P <.0001). The adjusted risk ratio for period 2 versus period 1 was 0.67, with 95% confidence limits of 0.54 to 0.82. Among inhabitants aged 30 to 74 years in the community of Göteborg, the CHD mortality rate decreased in 1995 as compared with 1990 (age-adjusted odds ratio 0.79, 95% confidence limits 0.68 to 0.92).

CONCLUSIONS

For consecutive patients aged <75 years who were hospitalized for AMI in the community of Göteborg, we found that in the thrombolytic era, major changes in medical and nonmedical treatment still took place associated with a continuing decrease in mortality rates during 3 years of follow-up. A similar reduction of CHD mortality rates was seen in the same age group within the community of Göteborg.

A description of the characteristics and outcome of patients hospitalized for acute chest pain in relation to whether they were admitted to the coronary care unit or not in the thrombolytic era

OBJECTIVES

To describe the characteristics and outcome of patients hospitalized for acute chest pain in relation to whether they were admitted to the coronary care unit (CCU) or not.

DESIGN

Prospective observational study with a follow-up of 2 years.

SETTING

Sahlgrenska University Hospital in Göteborg, Sweden.

SUBJECTS

All patients hospitalized due to acute chest pain during 6 months.

MAIN OUTCOME MEASURES

Mortality, use of medical resources, complications and previous history.

RESULTS

In all 1.592 patients were admitted to hospital for chest pain, of whom 1.136 (71%) were not directly admitted to the CCU. These patients differed from those directly admitted to the CCU, being older, including more women, having a higher prevalence of known congestive heart failure and a lower degree of initial suspicion of acute myocardial infarction (AMI). Among all patients with confirmed AMI only 58% were directly admitted to CCU. Overall, the occurrence of complications and the use of medical resources were less frequent in the patients not admitted to the CCU. The mortality during the subsequent 2 years was 16.8% for patients not admitted to the CCU and 18.5% for patients admitted to the CCU. When adjusting for various factors at baseline, patients admitted to the CCU had a relative risk of death during 2 years of follow-up being 1.23 0.87-1.73 (P=0.24) as compared with those not admitted to the CCU.

CONCLUSION

In a Swedish university hospital, more than two thirds of patients hospitalized for acute chest pain were not directly admitted to the CCU. They differed from those admitted to the CCU in several aspects. However, their unadjusted and adjusted mortality during the subsequent 2 years did not significantly differ from those admitted to CCU.

Comparison of mortality from acute myocardial infarction between 1979 and 1992 in a geographically defined stable population

This study documents mortality from acute myocardial infarction (AMI), in hospital and at 1 year, for each of 3 selected 1-year periods in a stable community over a 13-year period beginning in 1979 and continuing into the thrombolytic era, to detect any changes occurring in conjunction with the introduction of new therapies. Every patient with AMI occurring in a geographically defined stable community (Hamilton, Ontario, Canada) in 3 1-year periods (1979 to 1980 [n = 816], 1986 to 1987 [n = 816], and 1991 to 1992 [n = 831]) was identified and clinically characterized by standardized criteria. Subsequent in-hospital and 1-year survival were ascertained prospectively. The 3 cohorts were similar in prognostic factors. Mean age was progressively greater over the study period from 63 years in 1979 to 1980, to 67 years in 1991 to 1992 (p = 0.02). There was no change in in-hospital mortality rates from 1979 to 1980 (17%) and 1986 to 1987 (16%). However, from 1986 to 1987 and 1991 to 1992, in-hospital mortality decreased from 16% to 9% (p < 0.001) and 1-year mortality decreased from 26% to 19% (p < 0.001). For patients who survived the hospital phase of AMI, 1-year mortality did not change and was between 11% and 12% in each of the 3 study periods. From 1986 to 1987 and 1991 to 1992, there was an increase in the use of thrombolytic therapy from 5% to 44% of patients. The acute use of aspirin increased from 30% to 88% and the acute use of beta blockers increased from 19% to 48% of patients. The observed increase in use of these agents could account for half of the actual mortality reduction observed. This prospective population-based survey demonstrates improved in-hospital survival after AMI associated with increased use of established effective therapies between 1987 and 1992. The 1-year mortality of hospital survivors of AMI was unchanged throughout the period of study, remaining at 11% to 12%.

Metodologia para a estimativa de padrões de qualidade: o caso do infarto agudo do miocárdio

Os passos para estimar padrões de qualidade para a assistência médica a serem utilizados em programas de melhoria de qualidade e em mecanismos de financiamento são apresentados, tomando o exemplo do infarto agudo do miocárdio. A metodologia é baseada em evidências científicas existentes relativas a tecnologias atualmente em uso no tratamento daquela condição no país. A letalidade hospitalar foi estimada para conjuntos tecnológicos selecionados, correspondentes a unidades mais ou menos complexas. Os parâmetros básicos utilizados na estimativa de padrões foram a eficácia (percentual de redução na taxa de mortalidade) e o percentual correspondente ao referente (indicações) associado a cada tecnologia. Os padrões foram ajustados para idade e tempo decorrido até a admissão hospitalar. A letalidade hospitalar padrão estimada variou de 28% (assistência tradicional em enfermarias) a 8,5% (unidades coronarianas relativamente complexas). É apontada a escassez de dados relevantes sobre as características, especialmente a gravidade de pacientes com infarto agudo do miocárdio no Brasil. Outras possíveis limitações da metodologia proposta são discutidas.

Improved prognosis since 1969 of myocardial infarction treated in a coronary care unit: lack of relation with changes in severity

OBJECTIVE

To study changes from 1969 to 1983 in the prognosis of patients with acute myocardial infarction treated in a coronary care unit.

DESIGN

Mortality follow up of all patients with definite acute myocardial infarction.

SETTING

The coronary care unit of the Royal Melbourne Hospital, a tertiary referral centre.

SUBJECTS

4253 Patients (3366 men, 887 women) admitted from 1969 to 1983.

MAIN OUTCOME MEASURE

Mortality recorded at discharge from hospital and 12 months after admission.

RESULTS

Details of clinical findings, history, electrocardiograms, arrhythmias, and radiological findings were recorded on admission. Mean ages were 63 for women and 57 for men, and women had haemodynamically more severe infarcts than men. In the later years patients were older and had less severe infarcts. Overall, hospital mortality in men was 16.7% in 1969-73 and 8.5% in 1979-83 and declined in all grades of the Norris and Killip infarct severity indices compared with a constant 19.2% in women. Even after adjustment for age and severity by logistic regression, hospital mortality fell in men by an average of 8% (95% confidence interval 4% to 11%) a year but remained constant in women. By 1983 male mortality was 60% that of women of similar age and comparable severity of infarction. Mortality of hospital survivors at 12 months declined by 7% (4% to 9%) a year in both sexes, even after adjustment for age and severity, with a male to female mortality ratio of about 0.8. New indices were derived to predict mortality in hospital and at 12 months.

CONCLUSION

The observed declines in mortality cannot be explained by changes in severity of infarction or in prognostic characteristics of patients.

Mortality from myocardial infarction in different types of hospitals

Hospitals ranging from large urban teaching hospitals to small country hospitals were stratified into four levels of care and examined for their effectiveness of coronary care in relation to these levels. The crude hospital mortality among 2265 patients admitted for definite or possible acute myocardial infarction was 21% at level 1 (the most elaborate level), 22% at level 2, 21% at level 3, and 19% at level 4 (the least elaborate). Adjustment for age or other prognostic factors produced no significant differences across levels either for coronary care unit care or for combined coronary unit and ward care. Success in resuscitation was also similar across levels. These findings suggest that increased resources for coronary care units--whether for new services or for upgrading existing ones--may not be required.

Acute myocardial infarction: sex-related differences in prognosis

In 641 patients (535 men and 106 women) with acute myocardial infarction (AMI), a mortality of 16.63% was recorded among the former and one of 42.45% among the latter. No significant difference was observed in the age groups up to 40 years, in the group from 41 to 55 years, and in those over 71; the difference between percentages (17.09 vs 38.23) was instead statistically significant (p less than 0.01) in patients in the age group from 56 to 70 years. This difference was significant (p less than 0.01 or 0.001) with regard to mortality in diabetics (21.36% vs 46.34%), nondiabetics (13.09% vs 30.36%), hypertensives (19.72% vs 37.70%) and nonhypertensives (12.86% vs 36.11%), as well as in patients with previous infarction (33.36% vs 81.82%) and in those with first infarction (12.18% vs 31.39%). Since this phenomenon does not seem related to any particular feature of infarction nor to a particular predisposition to specific causes of death, the reasons for such severe prognosis in women require clarification.

Care of patients with a low probability of acute myocardial infarction. Cost effectiveness of alternatives to coronary-care-unit admission

We conducted a cost-effectiveness analysis to examine the clinical and economic consequences of alternatives to admission to a coronary-care unit for patients who have a relatively low probability of acute myocardial infarction. Despite the fact that all our assumptions were slanted to favor the current standard policy of admission to a coronary-care unit, our analysis shows that admission to an intermediate-care unit providing resuscitative facilities and prophylactic lidocaine is highly cost effective. For patients with about a 5 per cent probability of infarction, admission to a coronary-care unit would cost $2.04 million per life saved and $139,000 per year of life saved, as compared with intermediate care. For the expected number of such patients annually in the United States, the cost would be $297 million to save 145 lives. At probabilities of infarction up to about 20 per cent, the incremental cost to save a year of life by choosing a coronary-care unit over an intermediate-care unit would be higher than the estimated cost of saving a year of life by treating a 40-year-old man with mild hypertension. Our results suggest that many patients who have a low risk of acute myocardial infarction would be appropriate candidates for admission to an intermediate-care unit.

The course of patients with suspected myocardial infarction. The identification of low-risk patients for early transfer from intensive care

The hospital course of all patients admitted to a medical intensive-care unit (ICU) with suspected myocardial infarction was reviewed to test the feasibility of identifying patients suitable for earlier transfer from the ICU. Three hundred sixty patients admitted after presentation with uncomplicated chest pain could be stratified into three risk groups within 24 hours of admission to the ICU. One hundred sixty-eight patients (47 per cent), who were without major complications, elevation of total serum creatine phosphokinase, or electrocardiographic evidence of transmural infarction during the first day, could be designated "low-risk" patients. Three per cent of the low-risk patients subsequently met clinical criteria for infarction, 2 percent had late complications in the ICU, and none died. Rates of infarction, late complications in the ICU, and mortality in the hospital were significantly higher for patients at intermediate and high risk. Identification of low-risk patients for whom early transfer may be routinely indicated is feasible and could reduce by 55 per cent the total number of days that such patients spend in the ICU.

A Marxian interpretation of the growth and development of coronary care technology

Cost containment efforts will fail if they continue to ignore the structural relationships between health care costs and private profit in capitalist society. The recent history of coronary care shows that apparent irrationalities of health policy make sense from the standpoint of capitalist profit structure. Coronary care units (CCUs) gained wide acceptance, despite high costs. Studies of CCU effectiveness, using random controlled trials and epidemiologic techniques, do not show a consistent advantage of CCUs over non-intensive ward care or simple rest at home. From a Marxian perspective, the proliferation of CCUs and similar innovations is a complex historical process that includes initiatives by industrial corporations, cooperation by clinical investigators at academic medical centers, support by private philanthropies linked to corporate interests, intervention by state agencies, and changes in the health care labor force. Cost-effective methodology obscures the profit motive as a basic source of high costs and ineffective practices. Health-policy alternatives curtailing corporate involvement in medicine would reduce costs by restricting profit.

The elderly patient in the coronary care unit. I. Acute myocardial infarction

In a Coronary Care Unit (CCU) with no age barrier for admission, 21 percent of the patients admitted in 1976 were aged 70 or older. Myocardial infarction was documented in 55 of 130 elderly patients. The overall incidence of arrhythmias was similar to that for younger patients. The mean duration of stay in the unit and the CCU mortality (9.1 percent) were similar in both elderly and younger patients, as was the in-hospital mortality rate. Of the patients who survived hospitalization, 75.6 percent were still living 18.1 months after the myocardial infarction. The elderly patient is as likely as the younger one to benefit from admission to a CCU.

Effect of a coronary care unit on mortality from acute myocardial infarction

The mortality from acute myocardial infarction was compared for 2 years before the introduction of a coronary care unit (C.C.U.), and three and a half years after. The difference was not significant statistically (18% before, and 15% after). There was no reduction in the incidence of cardiac arrest in the C.C.U. period, but resuscitation from cardiac arrest was more successful. The results are considered in the light of previous studies, and the current status of coronary care in district general hospitals is discussed.

Distributing medical care services. Coronary care units in the United States and Sweden

Planning in the United States is based on an institution's perceived need, whereas in many other countries it is based on population need. These unique approaches to planning have led to widely differing distributions of facilities and services. Planning by the U.S. method leads to a more generous provision of services than does population-based planning. In both planning systems, the planning process appears of paramount importance, while the fundamental questions of effectiveness outcome and impact of medical care services are usually ignored. Even population-based planning either cannot or will not deal with the conflict between professional desire for highly developed technology on the one hand and treatment effectiveness on the other. Nevertheless, population-based planning has at least the virtue of providing a less expensive yet more efficient system. Physicians and the public appear able to adjust to the quite different resource provisions of the two planning systems; both the abundant U.S. supply and the restricted supply in Sweden are perceived as adequate.

Utilization of coronary care units in Sweden

Coronary care unit usage has expanded rapidly in all high income countries with little attention to effectivity or cost. A study of six randomly chosen Swedish units showed that larger units in teaching hospitals had significantly lower age-adjusted mortality rates, higher proportions of myocardial infarction patients, and greater productivity and efficiency. Comparisons with a study from the United States showed better results in the Swedish hospital units according to all variables measured. Although proof of effectiveness of CCU's is lacking, their continued use is assured. A less than optimal solution is a rational distribution of units based upon epidemiologically determined need, while stressing good organization and efficiency.

Histopathology of the conduction system in patients with atrioventricular or intraventricular conduction disturbances

In 9 lethal cases where clinical signs gave rise to the suspicion of acute myocardial infarct (AMI) where well-characterized e.c.g.-changes, permanent or intermittent, were found by monitoring, a very careful autopsy of the heart was carried out, combined with a meticulous histological investigation of the conduction system. Acute changes of mild degree in the conduction system were found only in one case, possibly explaining the left bundle branch block found in this case. In the remaining cases, nothing but chronic changes were found and they did not exceed significantly the changes otherwise to be found in the agegroups concerned in a "control series" of violent deaths not preceded by symptoms of heart disease. According to an estimate there was good correlation between the conduction disturbances demonstrated and the localization of histopathological changes in seven of nine patients; in one of the latter correlation was relatively good; correlation was dubious only in one case. On this basis the authors conclude that present changes in the conduction system which are assumed mainly to be age-related, are the factors to determine the type of conduction disturbances from which the patient will suffer if acute heart ischaemia sets in, for instance due to an AMI, in fact, changes by which he will be predisposed to such disturbances.

Myocardial infarction: a comparison between home and hospital care for patients

To compare the results of home and hospital treatment in men aged under 70 years who had suffered acute myocardial infarction within 48 hours 1895 patients were considered for study in four centres in south-west England. Four-hundred-and-fifty patients were randomly allocated to receive care either at home by their family doctor or in hospital, initially in an intensive care unit. The randomised treatment groups were similar in age, history of cardiovascular disease, and incidence of hypotension when first examined. They were followed up for up to a year after onset. The mortality rate at 28 days was 12% for the random home group and 14% for the random hospital group; the corresponding figures at 330 days were 20% and 27%. On average, older patients and those without initial hypotension fared rather better under home care. The patients who underwent randomisation were similar to those whose place of care was not randomised, except that the non-randomised group contained a higher proportion of initially hypotensive patients, whose prognosis was poor wherever treated. These results confirm and extend our preliminary findings. Home care is a proper form of treatment for many patients with acute myocardial infarction, particularly those over 60 years and those with an uncomplicated attack seen by general practitioners.

Mortality from acute myocardial infarction before and after establishment of a coronary care unit

A retrospective study of the mortality rate of acute myocardial infarction in two groups of patients treated before and after a coronary care unit was established showed no difference between them. Though it is difficult to compare two series retrospectively so far there are no well controlled studies to demonstrate clearly the value of coronary care units.