Five hundred patients with myocardial infarction monitored within one hour of symptoms.

Abstract

Of 2886 patients monitored during acute myocardial infarction, 500 were observed within one hour of the onset of symptoms. Half of the early admission group were admitted in response to emergency 999 calls and 435 of them travelled in resuscitation ambulances, where surveillance for arrhythmias was instituted. Pulmonary oedema occurred in 130 patients (26%), cardiogenic shock supervened in 60 (12%), and 115 (23%) died in hospital. Ventricular fibrillation was observed in 98 patients (20%). Forty two of them survived to be discharged, including 20 of the 24 with primary fibrillation which had occurred first in hospital. In only one case did primary ventricular fibrillation occur after the first 10 hours of onset of illness. Sinus bradycardia, atrial fibrillation, ventricular tachycardia, and ventricular fibrillation were all observed more frequently in patients admitted within one hour after the onset of symptoms than in those admitted later.An element of selection is inevitable when early admission is encouraged by the existence of a resuscitation ambulance system; this will depend in part on the early recognition of risk and the geographical location of the attack. These factors may bias the group towards relatively high risk. Nevertheless, prompt admission after myocardial infarction should improve survival by permitting successful management both of ventricular fibrillation and of other arrhythmias which may influence short term and long term prognosis. IntroductionLittle information is available in world reports on the complications of myocardial infarction when patients come under observation very early after the onset of symptoms. A series representing an unselected population cannot be obtained because data are collected only from those who seek treatment. In 1971 Adgey and colleagues reported' on the incidence of arrhythmias among 284 patients observed within one hour in a mobile coronary care unit manned by medical staff and, at that time, intended to operate in response to calls from general practitioners. Selection may not necessarily be similar in a community encouraged to make use of the emergency (999) telephone system for patients with severe chest pain or collapse; the Belfast results may also have been influenced by the availability of medical skills.Information on the results of early intervention is of particular value because of a resurgence of interest in prehospital care and early hospital admission. In Britain the Department of Health no longer actively discourages the creation of new coronary care and resuscitation ambulance programmes.2 3 District health authorities considering setting up such schemes within financial constraints will wish to know the potential benefits of early intervention.Taking advantage of data collected since the creation of an ambulance system4 -6 based on emergency services without direct medical intervention, we have reviewed retrospectively the records of 500 patients with confirmed myocardial infarction observed within 60 minutes of the onset of chest ...

Significance of arrhythmias during the first 24 hours of acute myocardial infarction treated with alteplase and effect of early administration of a beta-blocker or a bradycardiac agent on their incidence.

“…In previous studies (albeit without the use of Holter recording), it was reported to occur in 2.3% to 5.3% of patients during the first day"',24 and in 2.5% to 15% of patients during the first 2 weeks.22'25-28 The incidence is always lower in thrombolysed patients (eg, in the ISAM study, 4.3% versus 5.3% on day 124; in the ISIS-2 study, 4.4% versus 5.0% within 10 days25), but the very low incidence in our series may also be related to (1) the low-risk profile of our patients as discussed above and (2) a delayed start of the recording, missing the first 2.5 hours of chest pain. 3 The incidence of nonsustained VT (75%) or of AIVR (71%) in our series is much higher than the previously reported data of trials without Holter recording24 or with recording during a limited time period,29 since the benign hemodynamic effect of these arrhythmias may calculated figures in some smaller studies using Holter: 70% to 90% for nonsustained VT22,27,30 and 77% to 90% for AIVR.2227303' A noteworthy observation is that none of the patients with major arrhythmias during the first day had malignant recurrences during the ensuing 2 weeks (and vice versa). The limited size of our study and the low incidence of major events in our low-risk patients, Summarizing, we may conclude that (1) our data do not support the hypothesis that ,-blockers or bradycardiac agents might reduce the incidence of arrhythmias when used in conjunction with thrombolytic therapy, with the possible exception of atrial fibrillation in the alinidine group; (2) the pathogeneses of VT and VF early during acute myocardial infarction are clearly distinct; (3) VT or VF during the first 2 weeks is a marker for a larger infarct; (4) we could not detect a relation between malignant arrhythmias on day 1 and recurrences within the following 2 weeks; and (5) the presence of ST-segment normalization combined with the occurrence of a long run of AIVR predicts coronary reperfusion.…”

“…(2) The pathogeneses of VT and VF early during AMI are clearly distinct. (3) VT or VF during the first 2 weeks is a marker for a larger infarct. (4) We could not detect a relation between malignant arrhythmias on day 1 and recurrences within the following 2 …”

III Diretriz sobre tratamento do infarto agudo do miocárdio

“…O maior risco de fibrilação ventricular ocorre durante as primeiras 4h após o início dos sintomas 599,609 . A fibrilação ventricular observada na fase aguda (geralmente nas primeiras horas) do infarto, chamada de "fibrilação ventricular primária", ocorre em 4% a 18% dos pacientes com infarto [610][611][612] .…”

Analysis of the Treatment of Acute Myocardial Infarction Using Ambulance Records in Japanese Cities

“…Reports have described the shortening of decision time by means of early recognition of symptoms by education of patients, 5 the 'chain of survival' concept advocated by the American Heart Association, 6 thrombolytic therapy, 7-13 anticoagulant therapy, 7,8,14,15 emergency PTCA, 13,[16][17][18][19][20][21][22][23] assisted circulation 24,25 and a system to determine the effect of prehospital-initiated treatment of myocardial infarction. 26,27 Many reports have shown that case-fatality rates of AMI patients arriving quickly at specialty institutions are decreased by recanalization therapy and assisted circulation in contrast to patients not so treated.…”