Natural Ischaemic Preconditioning Before First Myocardial Infarction
There is a sharp rise in the rate of coronary heart disease diagnoses and chest pain consultations in the 90 days before a first heart attack. There is some evidence that chest pain and angina symptoms in this period have a beneficial effect on heart attack outcomes in hospital and shortly after discharge. However, the available evidence is lacking in three key areas. First it is based on a retrospective patient report of symptoms after the heart attack has occurred; this means that patients are required to survive their heart attack and may make errors when reporting prior symptoms. Second, evidence for an effect on longer term outcomes, and coronary outcomes in particular (e.g. coronary death, further heart attacks) are unknown. Third, there is conflicting evidence that these effects might differ by age, in men and women, and according to treatment in hospital.
The investigators hope to address the limitations in the evidence by performing a large, prospective study of the occurrence, timing and effect of different types of symptoms and disease diagnoses occurring before heart attack.
The investigators hypothesise that prospectively collected, clinical measures of chest pain symptoms and cardiovascular diagnoses in primary care will have a beneficial effect on short term coronary mortality and may have a beneficial effect on longer term coronary outcomes.
Coronary Heart Disease
Peripheral Arterial Disease
|Study Design:||Time Perspective: Retrospective|
|Official Title:||Natural Ischaemic Preconditioning Before First Myocardial Infarction: an Analysis of Prospectively Collected UK Electronic Primary Care Records Linked to the National Registry of Acute Coronary Syndromes|
- Recurrent myocardial infarction [ Time Frame: Up to seven years ] [ Designated as safety issue: No ]Myocardial infarction occurring thirty or more days after the study start date.
- Coronary mortality [ Time Frame: Up to seven years ] [ Designated as safety issue: No ]Coronary mortality, using ONS mortality statistics (ICD-10 codes I20-I25)
|Study Start Date:||September 2009|
|Estimated Study Completion Date:||December 2014|
|Estimated Primary Completion Date:||December 2013 (Final data collection date for primary outcome measure)|
MI without ischaemic preconditioning
Myocardial infarction unheralded by any previous cardiovascular disease diagnosis and without symptoms of chest pain in the previous 90 days.
MI with longstanding disease
Patients with myocardial infarction who have had diagnosed atherosclerotic disease for longer than 90 days preceding infarct.
MI with only chest pain
Patients with chest pain in the 90 days preceding MI, but with no prior atherosclerotic disease diagnoses.
MI with disease and chest pain
Myocardial infarction occurring with previously diagnosed atherosclerotic disease of longer than 90 days' duration, but with chest pain in 90 days preceding infarct.
|London School of Hygiene and Tropical Medicine|
|London, United Kingdom, WC1E 7HT|
|Principal Investigator:||Emily Herrett, MSc||London School of Hygiene and Tropical Medicine|
|Study Director:||Harry Hemingway, FRCP||University College, London|