Detailed diagram: Judging of acute myocardial infarction

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Detailed diagram: Judging of acute myocardial infarction

2021-12-03 13:06:58 85 ℃


Cardiac anatomy and electrocardiogram foundation

The heart is located in the overlook of the chest. Its location is equivalent to the range between the 2nd rib cartilage or the 5-8 thoracic vertebrae. The entire heart is 2/3 to the left side of the body's normal midline.

2/3 on the left side of the center

Direction: Back right - left front

The heart is inverted, and the cone is moving with a torrent of a peach. The heart is blunt, and the left front is adjacent to the chest wall.

1 to 2 cm inside the left fifth rib gap in the left side of the upper left side.

One pointed one: my heart, my heart

Three edges: left edge, right edge, lower edge

Two sides: front (chest rib)

Next () surface

Conduct system nerve domination and blood supply

The conductive system is subject to sympathetic nerves and vagus nerves

The sinus knot is bleeding from the sinus tunnel, 60% from the right coronary artery, 40% of the left crown back

80% of the atriosis of the rooms to the right coronary artery, 20% come from the left coronary artery



Change of T wave in AMI

T-band tip of acute period

(1) Presentation top or spike, voltage can be up to 2 mV

(2) There is a significant value for the early diagnosis of AMI

(3) may appear alone or change with the ST segment

(4) Not all AMI can be recorded

Evolution process of T wave

(1) The ST segment of the T wave is fused to the unidirectional curve;

(2) During the month, T wave is low, flat, inverted, is "coronary T wave";

(3) After several weeks to months, the inverted T wave gradually became shallow and erected.

Change of ST segment in AMI

(1) ST segment is raised for a long time

The ST segment elevation has gradually declined, suggests that myocardial microcirculation has not been perfused. It is common to have an early effective reperfusion intervention (thrombolytic or PCI), or intervention or PCI. There is no repetition of no recovery), and the thrombosis has not been self-suvel. When the ST paragraph is continuously raised for 2 weeks, the room wall tumor may be formed.

(2) ST segment falls in a short time

2 h rebounded by ≥ 50%, suggesting that criminal coronary is replenished, and the myocardium is effectively reperfined. The ST segment is dropped, the greater the decline, the more reperfusion is. More than an early successful reperfusion (thrombolytic or PCI), partially established in time for thrombusolysis or lateral circulation.

ST paragraph change

(3) Rapid fall after a passage of the ST segment

More than the reperfusion treatment, blocking the blood vessel is opened and the reperfusion damage is raised, and the role of the ST segment is reorganized. The role of serving the reperfusion injury disappears or improves, and the myocardial microcirculation has been effectively reperfined, the ST segment will fall again and continue to decline.

(4) ST segment elevation and falling alternate

More than a priority of the fibrillation system and anticoagulant system and anticoagulant system in the secondary in vivo. When the two alternately make the coronary blood vessels, the opening is alternated, and the patient is easily inferior. When the ST segment appears after 24 h, it should be considered that there is an additional infarction.

Change in Q wave in AMI

6 to 14 hours after AMI, a pathological Q wave in most patient ECG. New pathological Q wave is one of the basis for determining the diagnosis of AMI

There are two causes of pathological Q wave:

1 Organized myocardial necrosis, generally manifestative Q wave;

2 顿 心 心 一 电 电 电 电 失 失.. 波 波 波 波 波

Q wave evolution:

➤ Q wave is continuous in the family, suggesting that myocardial tissue is necrosis

➤ The Q wave portion disappears or becomes smaller: as seen in the early days of AMI, the suppression of the heart muscle is saved, and the reperfusion is obtained; if you see the advanced stage of AMI, small lesions, scar retreat and neighboring myocardial hypertrophy

ECG changes after reperfusion

The electrocardiogram ST-T change is a "gold standard" evaluated myocardial microcirculation blood flow reperfusion, and the prognostic information provided exceeds simple coronary angiography.

(1) ECG performance of coronary thrombolysis

➤ Raise the ST segment to fall within 2 h or by 30 min within 30 min (50%)

➤ There are reperfusion ventricular

(2) pathological Q wave

Effective reperfusion can make pathological Q wave do not appear or decrease, and the number of leaders, the proportion of the disappearance is increased (the microcirculation of myocardial tissue is 5 to 6 months after effective reperfusion).

The time period of the above indicators is significantly different, and the ST segment changes were observed in the early (after reperfusion, 90 min after reperfusion), and the T wave change was observed 12 to 24 h.

T-wave electrical alternation

When the T-wave electrical alternating point is complete, the amplitude, morphology and polarity of the electrocardiogram T wave appears step-up change. When the variation is low, the naked eye cannot be distinguished (microast-grade voltage), the microvolt type T wave is called alternating. The AMI has a T-wave electrode alternating is an independent predictor of malignant ventricular arrhythmia and sudden death.

Early detection of T-wave electrodes may predict the occurrence of malignant arrhythmia in acute period. T-wave electrical alternation in 4 to 6 weeks after myocardial infarction makes sense.

Sinus heart rate shock

Normal people often have sinus heart to accelerate the double phase change after acceleration, and the balance of autonomic neur is broken or disappeared from the balance of autonomic nerves. The sinus heart rate of AMI is weak, and the mortality rate is increased, and the malignant ventricular arrhythmia is immortal.

J wave

AMI is a j-hour prognosis, which belongs to the secondary J wave, and is often extended by QT intervals. Easy to send malignant chamber arrhythmia caulk 03

Myocardial infarction and electrocardiogram positioning

Left-to-hand-drying volatility

"6 + 2 phenomenon"

There are at least 6 leading ST sections and 2 leading ST sections.

ST segment lift: AVR ↑, and raise the level AVR ↑> V1 ↑

The ST segment pressure is low: V2-V6 (most evolving in V4-V6), and II, III, AVF (II leader most obvious), AVL pressure is not obvious or low

ECG can be manifested normal: seeing multiple vascular complex lesions or paid

Left-to-triathral electrocardiogram

n Male, 56 years old, left primary dried disease, A illustrated unopened electrical map, B illustrates chest pain episodes, I, II, III, AVF, V2-V6 lead ST segment significantly lower slope, T wave negative Two-way, AVR lead ST segment is high

Identification of forerunge infarction site

ECG Positioning myocardial infarction site flow chart


Cardiography Special ECG

Myocardial infarction with lbb

Electrocardiogram: lbbb combined with myocardial infarction. LBBB makes the chest transfer or lowering becomes unreliable, usually cover the heartbeat. The LBBB can be identified by a wide QRS wave group, a V6 lead-oriented RS wave recognition. In addition, T-wave is opposite to the main wave direction of the QRS wave group. ECG also shows III, AVF lead T wave two-way and inverted (arrows), opposite to the main wave of QRS, suggesting ischemia. These performances are specific, but the sensitivity to ischemic or infarct is not particularly high.

AMI and lbb diagnosis

• In 1996, the "New England Medical Journal" (NEngJMED) published the LBBB combined with AMI diagnostic criteria (Sgarbossa scoring criteria). Subsequent studies have proven that for lbb patients, Sgarbossa scores ≥ 3, diagnosed AMI specificity> 90%. Among them, the ST segment and QRS-waveness elevation elevation is LBBB combined with AMI specific diagnostic standards, and it helps to improve the detection rate of patients with vascular infarction patients with positive patients and angiography in myocardial markers.

For more than ten years, many documents including the 2013 US Cardiological Society / American Heart Society (ACC / AHA) Guide have adopted Sgarbossa standards as the diagnosis of LBBB combined with AMI. Some scholars have improved their original standards for problems with low SGARBOSSA score standards (rating ≥ 3, sensitive). SMIS (Smith), etc. shows that if the electrocardiogram is excessible, the ST segment lift / S wave vagration ≤ -0.20, the diagnostic sensitivity can reach 84%.

Myocardial infarction with lbb

Examples of lbbb combined with myocardial infarction (occurred). I, AVL leads can be seen that Q Waves, V5-V6 leads can be seen that the ST segment is lifted.

The nearest 2013 Stemi Guide is more consistent with our recommendation and recognizes the difficulties and uncertainty of LBBB-related cardiological diagnosis. In the latest version of the guide, LBBB is no longer equivalent to STEMI. Conversely, the guide that recognizes that the LBBB of most cases may not be new, especially when there is no contrast in the electrocardiogram; when the diagnosis is new or possible, the new LBBB has rarely occurs, may interfere with the ST segment elevation analysis, should not be used as an independent diagnosis The standard of acute myocardial infarction. These new guides no longer recommend emergency reperfusion treatment for new or possible new LBBBs as Stemi, which gives LBBB patients to diagnose acute myocardial infarction, recommended for chest ultrasonic electrocardiogram, troponin and patient clinical The state is evaluated. If it is still unclear that acute myocardial infarction, it should be converted to an interventional contrast examination to guide treatment.

Myocardial infarction with rbbb

ECG suggests that the right bundle belt block (RBB) combined with the front wall myocardial infarction, the patient's condition is critically ill, PCI treatment

DE Winter syndrome

DE WINTER syndrome?

The electrocardiogram related to DE Winter syndrome is: 1 Chest V1-6 lead J point is 1-3mm, ST segment is moved downward, then the T wave symmetry is high; 2QRS wave is usually not wide or mild Coading; 3 part patients have poor thoracic lead R wave rises; 4 most patient AVR lead ST sections lightly lift.

Verouden and DE Winter et al. Then summarized this electrocardiogram change into the paper, and the results suggest that de Winter accounts for approximately 2.0% of ACS patients. The average ECG recording time is 1.5 hours after the symptom. Emergency coronary angiography did not find significant left primary dried disease, about 2/3 patients were preceding a single disease. The criminal lesion is in front of the pre-drop, 86% of patients before the postoperative LAD blood flow is TIMI 0-1, and the ECG phenomenon after emergency PCI.

Typical de Winter integrated monogram

Typical de Winter integrated monogram

Typical de Winter integrated monogram

DE WINTER synthesis monitors must not evolve?

DE Winter integrated monoclutum changes is considered to be a "super acute phase" change, but this statement often corresponds to early T wave tip of STEMI patients. The same is completely occluded for the left front degradation. The DE WINTER syndrome does not only have T wave high changes, but also with the ST segment, the slope is low, and early views believe that this change is static, which can be directly developed as a turbulent myocardial infarction, basically Will not dynamically evolve into STEMI.

As the case reported, we found that DE Winter syndrome can also evolve into STEMI. This type of patient should be considered early changes in STEMI, or a special type of acute coronary syndrome, it is difficult to give Exact definitions, but regardless of the relationship between DE Winter syndrome and STEMI, it should be considered as Stemi's "Stemi Equivalent".

How much proportion of DE Winter syndrome can only be developed for STEMI, it is only necessary to rely on clinical observation. It is difficult to confirm by research. The reasons are two: 1DE Winter syndrome is relatively rare, and the high sample research fee is expensive. If the emergency PCI is in time The electrocardiogram may not be changed to the evolution. 2 It has been clear that the de Winter syndrome is caused by the proximal occlusion, and is a deadly myocardial infarction that requires emergency treatment. The clinical encounters such patients The task is the opening of the blood vessel this morning, rather than observing whether it evolved.

A case progressed as a DE WINTER syndrome of the front wall STEMI: V3-6 leaders can still be seen on the residual ST segment, but V1-2, I, AVL lead has been visible to the ST segment is high, with a lower wall Mirror change

Differential diagnosis of DE WINTER Comprehensive Exemptory ECM?

1 identify the super-acute ST-T change in acute myocardial infarction: super-epitonal electrocardiogram characteristic changes to the chest lead T wave, can be asymmetrical, the base portion is wide. It is an early change in coronary artery occlusion, and as myocardial ischemic injury is aggravated, it finally evolved into STEMI.

2 Differentiated with the slope of the ST segment at the ST segment at the rate of heart rate: the heart rate increases (if the flat moving test) often occurs on the ST segment, the slope is low, and it is currently related to the atrial complex, and there is no myocardial ischemia. . The simplest discovery is the simplest, important identification point is that DE Winter ST-T changes appear when heart rate does not increase.

3 identification with high potaemia: patients with hyperkalemia mainly appear to be a narrow substrate and symmetrical, high T wave, but not accompanied by the expression of slopes on the ST segment, combined with patient chest pain symptoms, myocardial injury markers Check, not difficult to identify.

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