One out of 3 heart attacks misdiagnosed is the finding of this British study. Errors mainly performed in heart failure patients over the age of 80 due to atypical test results and in female patients. Conclusions presented in the European Heart Journal which should recall specific symptoms in women, less known and recognized, which sometimes lead to slower management. Still involved, the progression in women of smoking, obesity and diabetes .
The authors recall the 2 main types of heart attack: the “classic” heart attack, myocardial infarction with elevation of the ST or STEMI segment and myocardial infarction without elevation of the ST or NSTEMI segment. In this second type, the patient presents the same signs, the classic symptoms and results in blood tests, but without elevation of the ST segment on the ECG which indicates the blocking of a cardiac artery. The two types of heart attack are managed differently, in particular, a STEMI diagnosed early enough can motivate anticoagulant treatment and immediate percutaneous coronary intervention (PCI) as well as the placement of a stent to keep the artery open. An NSTEMI is mainly managed with different drugs, but coronary intervention can also be considered at an early stage.
Researchers from the University of Leeds and other British research institutes analyzed data from 564,412 participants in the Myocardial Ischaemia National Audit Project cohort , diagnosed with a heart attack in the past 9 years. Researchers were particularly interested in how a change in diagnosis was associated with survival. Their analysis shows that overall,
· One third of patients diagnosed wrong initially,
· The factors associated with this diagnostic error are:
- the high age, more than 83 years old,
- gender, female: men have a reduced risk of 37% of initial diagnostic error vs women,
- results from atypical tests.
Specifically, 29.9% or 168,534 patients received an incorrect initial diagnosis,
- The diagnostic error generally deprived the patient of the immediate prescription of aspirin or thrombolytic treatment,
- certain factors including older age, rapid heart rate and heart failure have frequently been wrongly associated with NSTEMI.
- Compared to women, men had a reduced risk of 37% of having a wrong diagnosis in case of STEMI, and 29% in case of NSTEMI,
performing an ECG before hospitalization was associated with a better chance of a correct diagnosis.
0.5% of deaths could be avoided: at one year, the death rate for patients with STEMI is 5.6% vs 8.4% for an initial diagnosis of NSTEMI. Patients with NSTEMI have a 10.7% risk of death at 1 year but a 25.5% risk of error in diagnosis. The researchers calculated that if the 3.3% of STEMI patients and 17.9% of NSTEMI patients who received a misdiagnosis had received the correct diagnosis, in total more than 250 deaths could have been prevented.
The potential for improved management of the heart attack is significant, and even more so for the “NSTEMI” than the “STEMI”. But the prevention potential is just as important: everyone can reduce their risk of heart attack by adopting a healthy diet, maintaining a healthy weight, regular physical exercise and the absence of smoking .
New in the diagnosis of heart attack
The accumulation of lipid and calcium plaques in the arteries is a known cardiovascular risk factor. The analysis of the consistency of the coronary plaque, by angiography, allows the diagnosis of a patient’s cardiac risk . What researchers from the Heart Institute at the Intermountain Medical Center have just discovered is that the “soft” lipid-laden plaques, so often in the dock, are less dangerous than calcium deposits, which forms “hard” plaques in the arteries. For this, they analyzed the composition of the plaque of 224 patients for seven years.
“We initially thought that soft plaque was more likely to cause heart attacks. Our new research shows that it is calcified plaque that is most strongly associated with cardiovascular events , “said scientists at the latest scientific conference at the American College of Cardiology.
If their conclusions are confirmed, this would change the situation: it would now be necessary to take into account the “score” of coronary calcium to assess the risk of a patient. Thus, even with high cholesterol (and therefore an increased risk of formation of lipid plaques in the arteries), a patient with a score of zero would not have a risk of heart attack within five years, the researchers believe. This diagnosis would therefore remove unnecessary treatment from a part of the population that until now was considered at risk.