What is a septal infarct?
A septal infarct is a subtype of a heart attack. It happens when a part of the septum does not receive blood and oxygen. The lack of oxygen causes the heart cells behind the blockage to die.
Septal infarction can happen when an artery supplying the blood becomes occluded. A common cause of septal infarcts is an obstruction of the left anterior descending artery [1].
The most common cause of heart infarction is coronary artery disease. This condition is caused by atherosclerosis, which leads to obstruction of the blood flow [2].
The septal infarction results in a necrotic patch of non-functional cardiac tissue. With time, the affected region in the septum will turn pale. It will be a scar filled with fibrotic tissue.
The symptoms of septal infarction are the same as those of infarction in other parts of the heart. Among the most common presentations are:
- pain and pressure in the chest,
- pain radiation to the arm, jaw, or abdomen,
- shortness of breath,
- sweating,
- nausea,
- syncope [2].
In addition to the symptoms, a septal infarction will also present with changes in the ECG and elevated biochemical markers.
Common finding on ECG in septal infarction in ST-segment elevation in the lead V1, 2, 3, and 4. However, in septal infarcts, the elevation is most prominent in V1 and 2.
Biochemical markers characteristic of a heart infarction are troponin, myoglobin, and creatine kinase-MB.
However, sometimes the septal infarction can be silent without any symptoms or go unnoticed.
A myocardial infarction can go unnoticed when the symptoms are very mild. It is also possible that the symptoms will resemble a common, not dangerous, condition like indigestion [3].
A patient who suffered from a silent or unrecognized infarction in the past will still have changes in their ECGs. Often, they will be diagnosed with a septal infarction of unknown age.
Can a septal infarct kill you?
Yes, a septal infarct can potentially be fatal.
Any septal infarction can lead to complications. However, the bigger the infarction area, the more severe the consequences. Also, the deeper the dead tissue, the worse the outcome.
One of the most serious complications of a septal infarction is ventricular septal rapture. It is a very dangerous condition with a high mortality rate [4].
A rupture of the septum between the ventricles leads to acute heart failure. More than half of the affected patient collapses and suffers cardiogenic shock [5].
Other complications of a septal infarction can also be dangerous. Among them are:
- arrythmias,
- mitral regurgitation,
- left ventricular aneurism,
- emoboli [6].
What is the diagnosis of septal infarction?
The diagnosis of a septal infarction is based on typical symptoms. However, confirmation is often done by ECG and biochemical markers.
The doctors can diagnose an acute septal infarction or a septal infarction of an undetermined age. The second is a septal infarction that occurred in the past [3].
Classical changes on the ECG in a septal infarct are ST segment elevations in V1 to 4, with maximal elevations in V1 and V2.
Additionally, in acute septal infarcts, biochemical markers will be increased. The biochemical markers that are an indication of an infarction are troponin, myoglobin, and creatinine kinase-MB.
In cases where there is suspicion but the classical diagnostic methods fail, doctors can use more complex tools. For example, nuclear imaging can confirm an unclear diagnosis of a septal infarction.
Helpful in the differentiation of the septal infarction can also be echocardiography. This method can be especially useful in the identification of septal rapture (a dangerous complication of septal infarction) [7, 8].
Also, other methods like MRI or CT can be used by physicians to identify the septal infarct.
How often is a septal infarct misdiagnosed?
Septal infarcts can be serious and lead to dangerous complications and even death. Therefore, the time from the onset of a septal infarct until the treatment should be as short as possible.
Sadly, not all septal infarctions get diagnosed in time. Particularly atypical presentations of septal infarcts can be misdiagnosed. This can lead to life-long consequences, like heart failure.
It is difficult to say how often septal infarcts get misdiagnosed. There are differences between the cities, states, and countries.
Furthermore, there are also differences in the misdiagnosis rates between sexes. Women present more often with atypical symptoms of infarction. Generally, women have a nearly 60% higher chance of misdiagnosis than men [9].
A misdiagnosis can also occur after a technical mistake. One such example is the wrong placement of the ECG leads [10].
In the broader context of myocardial infarctions, rates of misdiagnosis range from 1.4 to 13% [11, 12, 13].
Some septal infarctions can also be silent or unrecognized. The silent septal infarction will not cause any symptoms. The unrecognized condition can be mistaken by the patient as an undangerous condition.
The unrecognized septal infarction can be mistaken, for example, for indigestion. In such cases, the patient might not even look for medical help. Unrecognized infarctions account for up to 40% of all infarctions [14].
However, as long as the patient has not visited the ED or a doctor with his condition, the unrecognized infarction does not count as misdiagnosed.
What is the treatment for a septal infarction?
Treatment of septal infarcts depends on the degree and size of the affected heart area. The treatment can consist of pharmacological therapy, lifestyle changes, and, in acute cases, cardiological interventions. In some cases, to deal with certain complications, surgery will be needed.
Among the commonly given drugs are
- morphine,
- oxygen,
- aspirin,
- betablockers,
- nitroglicerin,
- anticoagulats,
- antithrobotics,
- ACE inhibitors,
- statins [15].
Some septal infarctions will need international treatment. Typically, the most acute STEMI or ST-elevation myocardial infarction will require an intervention as soon as possible.
Also, a non-STEMI or non-ST elevation myocardial infarction may need interventional therapy. However, in the case of non-STEMI, the time window for the intervention is larger.
The type of intervention performed by the doctor in the case of an acute septal infarction is reperfusion therapy. It is called percutaneous coronary intervention, or PCI. This method allows for the resolution of the obstruction in the artery that causes the infarction.
In cases of ventricular septal rupture, surgical repair is the traditional treatment. However, percutaneous transcatheter repair using an occlude device is an emerging approach [16].
Generally, after one infection, the chances of getting a second one increase. Therefore, to lower this risk, lifestyle changes are prescribed to the patient.
The primary objective of the lifestyle adjustments is to lower blood pressure and cholesterol when they are too high [3].
Among the typically recommended changes are
- weight normalization,
- regular physical activity,
- healthy diet,
- reduction of stress,
- limitation of sodium and coffee,
- cessation of tobacco and alcohol [3].