Jeppe Launbjerg

Rapid Estimation of Left Ventricular Ejection Fraction in Acute Myocardial Infarction by Echocardiographic Wall Motion Analysis

Echocardiographic estimates of left ventricular ejection fraction (ECHO-LVEF) in acute myocardial infarction (AMI) were obtained by a new approach, using visual analysis of left ventricular wall motion in a nine-segment model. The method was validated in 41 patients using radionuclide ventriculography (RNV) and contrast ventriculography measurements of LVEF for comparison. ECHO-LVEF from the 41 patients correlated well with the reference methods (y = 1.5x - 14.7, r = 0.93; linear regression analysis; 95% confidence limit for a single determination of ECHO-LVEF was 17.2). Interobserver variability by linear regression was r = 0.89, SEE = 7.1 with a mean difference between paired observations of -1.5 +/- 6.9 (SD). In a random sample of 18 patients (45 observations), ECHO-LVEF allowed separation between RNV-LVEF values greater than or equal to 40 and less than 40, representing low and high risk groups following AMI. Thus, the results showed that simple, readily available wall motion-derived estimates of LVEF were as closely associated with LVEF measured by standard reference methods as were previously published, more cumbersome, planimetric echocardiographic methods. Reporting on global LVEF function in LVEF units rather than in nonstandardized wall motion scores of index values may facilitate intra- and interhospital communication and the use of optimized echocardiographic risk stratification after AMI.

Long-Term Risk of Death, Cardiac Events and Recurrent Chest Pain in Patients with Acute Chest Pain of Different Origin

The purpose of the study was to describe the prognosis of patients with acute chest pain of different origin, but without myocardial infarction (non-AMI). A total of 204 patients were included. In 56, a definite diagnosis was obtained within 24-48 H of admission. The remaining 148 patients underwent the following examinations: exercise test, myocardial scintigraphy, echocardiography, Holter monitoring, hyperventilation test, oesophago-gastro-duodenoscopy, oesophageal manometry, oesophageal pH monitoring, Bernstein test, physical chest wall examination, bronchial histamine test, chest X-ray and ultrasonic upper abdominal examination. Ischaemic heart disease (IHD) was diagnosed in 64 patients, 81 had gastro-oesophageal disorders, 58 chest wall disorders, 9 pericarditis, 5 pulmonary embolism, 4 pneumonia/pleuritis, 3 pulmonary cancer, 2 dissecting aortic aneurysm, 1 aortic stenosis and 1 herpes zoster. During follow-up of 33 months, 31 of the 64 patients with IHD had a cardiac event (cardiac deaths, non-fatal AMI, bypass surgery or PTCA), whereas only 3 event occurred among the 140 patients without IHD (p < 0.00001). However, the frequency of readmissions and of recurrent episodes of chest pain were similar in the 3 major diagnostic groups (NS). To conclude, the high-risk subset of a non-AMI population can be identified by means of non-invasive cardiac examination. The remainder who have other diagnoses are at low risk. However, the morbidity is high with frequent readmissions and recurrent episodes of chest pain and the need for development of strategies with regard to diagnosis and treatment of these patients are emphasized.

Risk Stratification after Acute Myocardial Infarction by Means of Echocardiographic Wall Motion Scoring and Killip Classification

In order to perform risk stratification, 195 consecutive, unselected patients with acute myocardial infarction (AMI) underwent independent echocardiographic and clinical evaluation of their left ventricular function by means of the wall motion index (WMI) and Killip classification 5 days after AMI. The patients were prospectively allocated to a low, medium or high risk class depending on WMI alone, and the 1-year mortality in these classes was 2, 34 and 37%, respectively (p < 0.0001). The 1-year mortality of the patients in Killip class I, II, or III and IV was 6, 26 and 48%, respectively (p < 0.00001). The number of patients allocated to the low risk group by means of WMI was 87, and the number of patients in Killip class I was 86. Since these groups were not identical, a total of 103 patients, i.e. 53% of the study population, could be identified as low risk patients regarding 1-year mortality 5 days after AMI, when WMI and Killip classification were used in combination. We conclude that the combination of echocardiographic and clinical evaluation of left ventricular function after AMI provides a strong and yet very simple procedure to identify low risk patients, which could be easily implemented in the routine work of coronary care units.

Echocardiographic Algorithms for Admission and Predischarge Prediction of Mortality in Acute Myocardial Infarction

To develop improved prognostic algorithms for routine bedside use in acute myocardial infarction (AMI), the prognostic value concerning 2- and 12-month mortality of an early (within 72 hours after AMI) resting echocardiogram was defined in 201 consecutive patients. The relation between (1) the clinical variables (age, sex, prior and repeat AMI, arrhythmias, cardiac arrest, early [less than 72 hours after AMI] and late heart failure, early and maximal in-hospital Killip class, and maximal creatine kinase-MB isoenzyme), (2) early myocardial performance by echocardiography, and (3) mortality was characterized by Kaplan-Meier survival curves and receiver-operating characteristic curves based on Cox regression model. Only age and clinical heart failure in terms of the maximal in-hospital Killip class had independent predictive value of death (p less than 0.05) when an early echocardiographic estimate of left ventricular ejection fraction (LVEF) was included in the multivariate statistical models. The following 2 optimized algorithms for admission and predischarge calculation of risk of mortality at 2 and 12 months were developed based on the Cox model, using combinations of age, maximal Killip class and early echocardiographic LVEF: mortality at 2 months = 1 - exp - [0.051 x exp [0.044 x (age -60) - (0.117 x (LVEF - 40)]]; and mortality at 1 year = 1 - exp - [0.101 x exp [0.408 x (maxKillip - 1) - (0.061 x (LVEF - 40)]]. Discriminative power for prediction of mortality of the predischarge algorithm in an independent population of 195 patients 5 days after AMI compared favorably with that obtained in the original population, confirming the validity of the proposed method of prognostication.

Ten-Year Mortality of Patients Admitted to Coronary Care Units with and without Myocardial Infarction

The purpose was to evaluate the 10-year mortality in patients with acute chest pain suspected of myocardial infarction with (AMI) and without (non-AMI) confirmed diagnosis and to determine risk factors from the medical history and the diagnosis at discharge. One-thousand eight-hundred and ninety-seven non-AMI patients and 1,401 patients with AMI consecutively admitted to 1 of 16 coronary care units participating in The Danish Verapamil Infarction Study were included. During follow-up, 630 deaths occurred among the non-AMI patients and 415 of these could be classified as cardiac deaths. Multivariate analysis identified the following risk factors containing independent prognostic information about mortality for non-AMI patients: age, previous AMI, sex, and diabetes. In patients with AMI the risk factors were: age, previous AMI, clinical heart failure, diabetes, and angina pectoris. By including the diagnosis at discharge for non-AMI patients in the Cox analysis, the prognostic significance was compared to the variables from the medical history. Only the diagnoses bronchopneumonia, musculoskeletal disorders and observatio sine indicatione therapiae added independent prognostic information. We conclude that non-AMI patients are at high risk for mortal events in the long term. High-risk patients can be identified from their medical history, whereas the diagnosis at discharge only adds limited prognostic information. All non-AMI patients should be carefully evaluated regarding coronary artery disease at the time of discharge in order to improve the risk stratification, treatment and prognosis.

Sensitivity and specificity of echocardiographic identification of patients eligible for safe early discharge after acute myocardial infarction

In a prospective clinical trial of 195 consecutive unselected patients with acute myocardial infarction (AMI), systematic blinded clinical and echocardiographic examinations were performed by two observers on day 5. The purpose was to define low-risk patients with regard to in-hospital and 2-month mortality and predict the potential costs (lost patient lives) and benefits (saved in-patient days) if as a routine procedure these low-risk patients were discharged earlier. By design, low-risk patients as defined by clinical criteria were allocated to discharge on days 7 to 10 and by echocardiographic criteria on days 5 to 7 after AMI. The sensitivity of the echocardiographic low-risk identification procedure was more than twofold higher than the sensitivity of clinical low-risk identification (49% vs 24%). Both procedures were safe with a specificity of 100% for cardiac mortality. Optimal identification of low-risk patients was provided by combining data from echocardiographic and clinical evaluations (sensitivity 59%). Results of the study suggest that a bedside echocardiographic approach to estimation of global left ventricular function is more sensitive and equally specific and therefore more efficient for risk stratification on post-AMI day 5 than clinical examination alone. Thus echocardiographic examination allows identification of a larger subset of patients with AMI (greater than 40% of the population alive on day 5) who can be discharged earlier and safely, with a potential saving of in-patient days of 436 days in 87 low-risk patients minus the cost of echocardiographic studies in 195 patients. However, the best prediction was obtained by combining clinical and echocardiographic examination.(ABSTRACT TRUNCATED AT 250 WORDS)

Risk factors related to the 7-year prognosis for patients suspected of myocardial infarction with and without confirmed diagnosis.

This study prospectively evaluates the long-term prognosis of patients admitted with chest pain under suspicion of acute myocardial infarction (AMI) with and without confirmed diagnosis. All patients below 76 years of age, free of other severe diseases and alive at discharge, who were admitted to a coronary care unit of a well-defined region during 1 year, constituted the study population. In all, 275 patients with and 257 patients without confirmed AMI (non-AMI) were included. During 7 years of follow-up, 122 cardiac events (96 cardiac deaths and 26 nonfatal AMI) occurred in the AMI patients, and 69 (44 cardiac deaths and 25 nonfatal AMI) were observed in the non-AMI patients. Using univariate analysis, the following risk variables were significantly related to an impaired prognosis of non-AMI patients: age, a history of previous AMI, angina pectoris, clinical heart failure, diabetes and ST or T changes in the electrocardiogram (ECG) on admission. By multivariate analysis, the following risk factors contained independent prognostic information for non-AMI patients: (1) a history of angina pectoris and (2) ST and T changes on the ECG on admission. We conclude that a subset of non-AMI patients at high risk for cardiac events even in the long term can be identified from the medical history and the ECG on admission. These patients should be carefully evaluated prior to discharge, whereas patients without signs of ischemic heart disease have an excellent prognosis.

The long-term predictive value of an exercise thallium-201 scintigraphy for patients with acute chest pain but without myocardial infarction.

BackgroundPatients who are hospitalized because of chest pain and suspected acute myocardial infarction, but in whom the diagnosis is ruled out, are at high risk for subsequent cardiac events (cardiac death or nonfatal acute myocardial infarction). Risk stratification was done for 158 such patients who underwent exercise thallium-201 scintigraphy at the time of discharge. MethodsThirty-eight patients (24%) were women, and all patients were followed for 7 years. The diagnostic sensitivity, specificity, and predictive value of thallium scintigraphy for the identification of patients having subsequent cardiac events during follow-up was calculated. ResultsA cardiac event occurred in 41 patients during the follow-up period. Presence of both transient and permanent defects and abnormal ST-segment responses during thallium scintigraphy were significantly associated with an impaired prognosis (P< 0.0001). The highest sensitivity (85%) was achieved by the combination of transient defect with or without persistent defect and with or without abnormal ST-segment response. The highest specificity was provided by a transient defect (90%), and the predictive value of a positive test result was 60%. Seventeen of 29 patients with a transient defect had a cardiac event during follow-up. Patients with normal test results had excellent prognoses; 93% of 82 patients were free of cardiac events during follow-up. ConclusionsExercise thallium-201 scintigraphy is suitable for long-term risk stratification in patients with chest pain and suspected but unconfirmed myocardial infarction, because high- and very low-risk subsets can be identified at the time of discharge.

Frequency of Pulmonary Embolism in Patients Admitted with Chest Pain and Suspicion of Acute Myocardial Infarction but in Whom this Diagnosis Is Ruled Out

The purpose of this study was to determine the frequency of pulmonary embolism in patients admitted with acute chest pain but without myocardial infarction (non-AMI patients). We examined 175 consecutive non-AMI patients without unstable angina pectoris within the first 48 h of admission. The patients were first examined by perfusion pulmonary scintigraphy. If the scintigraphy was abnormal, it was combined with a 81mKr ventilation scintigraphy. Perfusion scintigraphy was abnormal in 21 patients, and the subsequent combined perfusion/ventilation scintigraphy was used to identify 5 patients (2.5%) who had a high probability for pulmonary embolism, which was not clinically suspected at the time of admission. Three of these 5 patients had a decreased arterial oxygen tension upon admission, and 3 had abnormalities in their electrocardiogram. Pulmonary embolism only occurred in 2.5% of the non-AMI patients. The prognosis of untreated patients, however, it markedly worse as compared with treated patients. We, therefore, suggest that pulmonary scintigraphy be performed in non-AMI patients who have uncharacteristic electrocardiographic changes and/or a low arterial partial oxygen tension when no other abnormality has been found within 24 h of admission.

1- and 7-year risk of cardiac events in relation to Holter monitoring in patients admitted with chest pain in whom AMI is not confirmed

The prognostic value of ventricular premature beats (VPBs) was evaluated in 198 patients with chest pain (non-AMI patients) in whom the diagnosis of acute myocardial infarction was ruled out after admission to hospital. VPBs were registered at the time of discharge during a 24-hour Holter monitoring. The amount of cardiac events (CEs) were analyzed after 1 and 7 years follow-up. After 1 year, CEs were seen in 9% of the non-acute myocardial infarction (AMI) patients. After 7 years, 51 CEs (20 nonfatal AMIs and 31 cardiac deaths) had occurred (25%). After 1 year, only pairs of VPBs were associated with an increased risk of CEs. CEs were seen in 25% of the patients with pairs of VPBs and in 6% of the patients without pairs (p<0.01). The occurrence of CEs after 7 years was related to the presence of pairs of VPBs and multiform VPBs. Fifty-five percent of the patients with pairs of VPBs had CEs during the long-term follow-up, compared with 22.5% without pairs (p<0.0005). CE was seen in 48.9% of the patients with multiform VPBs, compared with 19.0% without multiform VPBs (p< 0.0001). Thus, Holter monitoring seems to be of better value for predicting long-term prognosis than for predicting short-term prognosis in non-AMI patients. The presence of multiform VPBs or pairs of VPBs is strongly associated with an increased risk of CE after 7 years. Non-AMI patients with pairs of VPBs or multiform VPBs should be considered as high-risk patients.