Björn W. Karlson

Factors associated with survival to hospital discharge among patients hospitalised alive after out of hospital cardiac arrest: change in outcome over 20 years in the community of Göteborg, Sweden

Objective: To describe the change in survival and factors associated with survival during a 20 year period among patients suffering from out of hospital cardiac arrest and being hospitalised alive. Patients: All patients hospitalised alive in the community of Göteborg after out of hospital cardiac arrest between 1 October 1980 and 1 October 2000 were included. Methods: Patient data were prospectively computerised with regard to factors at resuscitation. Data on medical history and hospitalisation were retrospectively recorded. Patients were divided into two groups (the first and second 10 year periods). Setting: Community of Göteborg, Sweden. Results: 5505 patients suffered from cardiac arrest during the time of the survey. Among them 1310 patients (24%) were hospitalised alive. Survival (discharged alive) was 37.5% during the first part and 35.1% during the second part (NS). The following were independent predictors of an increased chance of survival: ventricular fibrillation/tachycardia as the first recorded rhythm (odds ratio (OR) 3.46, 95% confidence interval (CI) 2.36 to 5.07); witnessed arrest (OR 2.50, 95% CI 1.52 to 4.10); bystander initiated cardiopulmonary resuscitation (OR 2.00, 95% CI 1.42 to 2.80); the patient being conscious on admission to hospital (OR 6.43, 95% CI 3.61 to 11.45); sinus rhythm on admission to hospital (OR 1.53, 95% CI 1.12 to 2.10); and treatment with lidocaine in the emergency department (OR 1.64, 95% CI 1.16 to 2.31). The following were independent predictors of a low chance of survival: age > 70 years (median) (OR 0.65, 95% CI 0.47 to 0.88); atropine required in the emergency department (OR 0.35, 95% CI 0.16 to 0.75); and chronic treatment with diuretics before hospital admission (OR 0.59, 95% CI 0.43 to 0.81). Conclusion: There was no improvement in survival over time among initial survivors of out of hospital cardiac arrest during a 20 year period. Major indicators for an increased chance of survival were initial ventricular fibrillation/tachycardia, bystander cardiopulmonary resuscitation, arrest being witnessed, and the patient being conscious on admission. Major indicators for a lower chance were high age, requirement for atropine in the emergency department, and chronic treatment with diuretics before cardiac arrest.

Mortality and Morbidity in Diabetic and Nondiabetic Patients During a 2-Year Period After Coronary Artery Bypass Grafting

OBJECTIVE To describe mortality and morbidity during a 2-year period after coronary artery bypass grafting (CABG) among diabetic and nondiabetic patients. RESEARCH DESIGN AND METHODS All the patients in western Sweden in whom CABG was undertaken between June 1988 and June 1991 and in whom concomitant procedures were not performed were registered prospectively. The study was a prospective follow-up. RESULTS Diabetic patients (n = 268) differed from nondiabetic patients (n = 1,859) in that more women were included, and the patients more frequently had a previous history of myocardial infarction (MI), hypertension, congestive heart failure, intermittent claudication, and obesity. Diabetic patients more frequently required reoperation and had a higher incidence of peri- and postoperative neurological complications. Mortality during the 30 days after CABG was 6.7% in diabetic patients versus 3.0% in nondiabetic patients (P < 0.01). Mortality between day 30 and 2 years was 7.8 and 3.6%, respectively (P < 0.01). During 2 years of follow-up, a history of diabetes appeared to be a significant independent predictor of death. Whereas the development of MI after discharge from the hospital did not significantly differ between the two groups; 6.3% of diabetic patients developed stroke versus 2.5% in nondiabetic patients (P < 0.001). CONCLUSIONS Diabetic patients have a mortality rate during the 2-year period after CABG that is about twice that of nondiabetic patients during both the early and late phase after the operation.

The epidemiology of out-of-hospital 'sudden' cardiac arrest.

It is difficult to assemble data from an out-of-hospital cardiac arrest since there is often lack of objective information. The true incidence of sudden cardiac death out-of-hospital is not known since far from all of these patients are attended by emergency medical services. The incidence of out-of-hospital cardiac arrest increases with age and is more common among men. Among patients who die, the probability of having a fatal event outside hospital decreases with age; i. e. younger patients tend to more often die unexpectedly and outside hospital. Among the different initial arrhythmias, ventricular fibrillation is the most common among patients with cardiac aetiology. The true distribution of initial arrhythmias is not known since several minutes most often elapse between collapse and rhythm assessment. Most patients with out-of-hospital cardiac arrest have a cardiac aetiology. Out-of-hospital cardiac arrests most frequently occur in the patients home, but the prognosis is shown to be better when they occur in a public place. Witnessed arrest, ventricular fibrillation as initial arrhythmia and cardiopulmonary resuscitation are important predictors for immediate survival. In the long-term perspective, cardiac arrest in connection with acute myocardial infarction, high left ventricular ejection fraction, moderate age, absence of other heart failure signs and no history of myocardial infarction promotes better prognosis. Still there is much to learn about time trends, the influence of patient characteristics, comorbidity and hospital treatment among patients with prehospital cardiac arrest.

Early prediction of acute myocardial infarction from clinical history, examination and electrocardiogram in the emergency room

The possibility of early prediction of acute myocardial infarction (AMI) was assessed in 7,157 consecutive patients coming to our emergency room during a 21-month period with chest pain or other symptoms suggestive of AMI. Of these patients 921 developed an AMI during the first 3 days in the hospital. Of the 4,690 patients admitted to hospital, 1,576 (34%) had a normal admission electrocardiogram, and 90 of these (6%) developed AMI. Of 1,964 patients with an abnormal electrocardiogram without signs of acute ischemia (42% of those admitted), 268 (14%) developed AMI, and 563 (51%) of 1,109 patients with acute ischemia on the electrocardiogram (24%) developed AMI. All patients were prospectively classified in the emergency room on the basis of history, clinical examination and electrocardiogram into 1 of 4 categories, according to the initial degree of suspicion of AMI. Of 279 admitted patients judged to have an obvious AMI (6% of the 4,690), 245 (88%) actually developed AMI; of 1,426 with a strong suspicion of AMI (30%), 478 (34%) developed one; of 2,519 with a vague suspicion of AMI (54%), 192 (8%) developed one; and of 466 with no suspicion of AMI (10%), 6 (1%) developed one. Thus, only a low percentage of the patients with a normal initial electrocardiogram or a vague initial suspicion of AMI developed a confirmed AMI.

Effect of a media campaign on delay times and ambulance use in suspected acute myocardial infarction

The early phase in suspected acute myocardial infarction (AMI) is particularly critical. More than 50% of deaths from coronary artery disease occur outside the hospital mainly due to ventricular fibrillation.1 Recent experiences strongly indicate that early intervention with thrombolysis2–4 and β blockers5,6 can limit myocardial damage and thereby improve prognosis. Delay times in suspected AMI have remained stable over the years. Therefore, a media campaign was started in the urban area of Goteborg, Sweden, with the intention to shorten delay times and to increase ambulance use in patients with suspected AMI.

Localization of pain in suspected acute myocardial infarction in relation to final diagnosis, age and sex, and site and type of infarction

OBJECTIVES To describe the localization of pain in consecutive patients admitted to the coronary care unit for possible acute myocardial infarction (AMI) and to relate it to the development of AMI, age, and gender. DESIGN Prospective evaluation. SETTING Sahlgrenska Hospital, covering half the area of the city of Göteborg, with half a million inhabitants. SUBJECTS Nine hundred three consecutive patients admitted to the coronary care unit for possible AMI between 24 and 87 years old with a mean age of 64 years. OUTCOME MEASURES Localizations of pain according to a self-constructed figure. Patient were approached between 1 and 14 days after onset of symptoms and asked to describe the localization of pain according to the figure, including nine positions on the chest, left and right arm, neck, and back. RESULTS AMI developed in 50% of patients during the first 3 days in hospital. Patients in whom AMI developed localized their pain to an extent similar to those without AMI in seven of nine chest areas. However, patients with AMI reported pain in the upper right square of the chest more frequently (p < 0.001) and in the middle left square of the chest less frequently (p < 0.01) than did patients without AMI. Pain in both the right (p < 0.001) and left arms (p < 0.01) was more frequently reported by patients who had AMI. Among patients with AMI, women reported pain in the neck (p < 0.05) and in the back (p < 0.01) more frequently than did men. Compared with elderly patients, younger patients reported pain more frequently in the left arm (p < 0.01), right arm (p < 0.01), and neck (p < 0.05). CONCLUSIONS Among consecutive patients with possible AMI admitted to the coronary care unit, patients who had confirmed AMI reported pain in both arms more frequently than did patients without AMI. However, both groups described their chest surface distribution of pain similarly in the majority of positions, thereby indicating that the localization of chest pain is of limited use in predicting which patients will eventually have AMI.

Prognosis in myocardial infarction in relation to gender

We studied 921 consecutive patients admitted to a single hospital for acute myocardial infarction during a period of 21 months and related their prognosis to gender. Women (n = 300, 33%) were on average 7 years older (p < 0.001) and more frequently had a previous history of hypertension (p < 0.001) and congestive heart failure (p < 0.001) than did men. They also tended to delay longer in seeking medical treatment and more often presented with only vague symptoms (p < 0.05). The in-hospital mortality for women was 19% versus 12% for men (p < 0.01). Women more often showed signs of congestive heart failure (p < 0.05) despite smaller infarcts as estimated from enzyme levels (p < 0.05). Total mortality during 1 year was 36% in women and 25% in men (p < 0.01). In a multivariate analysis, female gender did not appear as an independent risk factor for death. During 1 year of follow-up no differences in morbidity were observed between the sexes. We conclude that if women fare worse than men after suffering an acute myocardial infarction, the increased mortality is accounted for by older age.

Patients admitted to the emergency room with symptoms indicative of acute myocardial infarction

Abstract. All 7157 patients (55% men) admitted to the emergency room with chest pain or other symptoms indicative of acute myocardial infarction during a period of 21 months were registered consecutively. Chest pain was reported by 93% of the patients. On the basis of history, clinical examination, and electrocardiogram in the emergency room, all patients were prospectively classified in one of four categories: (i) obvious infarction (4% of all patients): (ii) strongly suspected infarction (20%): (iii) vague suspicion of infarction (35%); and (iv) no suspected infarction (41%). In patients with no suspected infarction (n = 2910), musculoskeletal (26%), obscure (21%) and psychogenic origins (16%) of the symptoms occurred most frequently. We conclude that few of the patients had an obvious infarction on admission, and that a musculoskeletal origin of the symptoms occurred most frequently in patients with no suspected infarction.

Determinants of an impaired quality of life five years after coronary artery bypass surgery

OBJECTIVE To identify determinants of an inferior quality of life (QoL) five years after coronary artery bypass grafting (CABG). SETTING University hospital. PARTICIPANTS Patients from western Sweden who underwent CABG between 1988 and 1991. MAIN OUTCOME MEASURES Questionnaires for evaluating QoL before CABG and five years after operation. Three different instruments were used: the Nottingham health profile (NHP), the psychological general wellbeing index (PGWI), and the physical activity score (PAS). RESULTS 2121 patients underwent CABG, of whom 310 died during five years’ follow up. Information on QoL after five years was available in 1431 survivors (79%). There were three independent predictors for an inferior QoL with all three instruments: female sex, a history of diabetes mellitus, and a history of chronic obstructive pulmonary disease. Multivariate analysis showed that a poor preoperative QoL was a strong independent predictor for an impaired QoL five years after CABG. An impaired QoL was also predicted by previous disease. CONCLUSIONS Female sex, an impaired QoL before surgery, and other diseases such as diabetes mellitus are independent predictors for an impaired QoL after CABG in survivors five years after operation.

An evaluation of the results of media and educational campaigns designed to shorten the time taken by patients with acute myocardial infarction to decide to go to hospital.

OBJECTIVE: To describe the benefits and pitfalls of educational campaigns designed to reduce the delay between the onset of acute myocardial infarction (AMI) and its treatment. METHODS: All seven educational campaigns reported between 1982 and 1994 were evaluated. RESULTS: The impact on delay time ranged from a reduction of patient decision time by 35% to no reduction. One study reported a sustained reduction that resulted in the delay time being halved during the three years after the campaign. The use of ambulances did not increase. Only one study reported that survival was unaffected. There was a temporary increase in the numbers of patients admitted to the emergency department with non-cardiac chest pain in the initial phase of educational campaigns. CONCLUSION: The challenge of shortening the delay between the onset of infarction and the start of treatment remains. The campaigns so far have not been proved to be worthwhile and it is not certain that further campaigns will do better. New media campaigns should be run to establish whether a different type of message is more likely to change the behaviour of people in this life-threatening situation.