Cardiac ischemia and cardiac infarction are both conditions that result when heart muscles fail. Cardiac ischemia is the condition of the heart whereby there is a decreased supply of blood to the tissues of the heart(Thygesen, et al., 2007). When this happens, an individual is likely to experience angina pectoris or chest pain. Cardiac infarction, on the other hand, is the condition where the heart tissue dies because of lack of blood supply. This condition is caused by cardiac ischemia that is untreated and has lasted for a long time.
The main grounds of the two ailments are the coronary artery spasm and presence of blood clot within the arteries in the heart (Thygesen, et al., 2007). Risk factors such as excessive smoking, high cholesterol levels, hypertension, and diabetes mellitus among others could also lead to the conditions.
An electrocardiogram is an important diagnostic tool used by medical practitioners to test patients who show symptoms and signs of cardiac ischemia and infarction. According to Thygesen et al (2007), positive results show anomalies in QRS complex, T wave and ST-segment. For patients without the cardiac ischemia and infarction, the ECG test would be nonspecific or normal. The presence of the abnormalities is the confirmation that a patient is suffering from the any of the two conditions.
Patients who are found to have cardiac ischemia or infarction would not show the same findings. The findings of ECG are influenced by a number of factors such as the duration that a patient has stayed with the condition, the size of the infection and the anatomic location of the infection (Thygesen, et al., 2007). The different findings would help the medical professionals to know the severity of the condition and then decide on the best measures to help the patient.
The most common life-threatening cardiac arrhythmias are Supraventricular tachycardia and atrial fibrillation. This is an abnormal heartbeat rhythm where the sinoatrial nodes (SA node) are not the ones that control the heart beat(Daubert, et al., 2006). In normal rhythms, SA nodes act as the normal heart timers, but in SVT other areas of the heart beat faster than the normal timers. The source that triggers this abnormal rhythm is above the ventricles (in supra) and the impulse then spreads down to the ventricles. This abnormal impulse forces the heart to beat faster than the normal sinus rhythm. The heart rate could go as high as 140-240 heartbeats in every minute. The episodes could last only for a short time or even go exist for many hours before it stops.
The occurrences are known as episodes and the time gap between them could vary greatly. Victims could experience several short episodes within one day or even have only 2-3 episodes in a whole year (Daubert, et al., 2006). Most people experience episodes that fall between the two extreme ends and may experience them regularly.
Atrial fibrillation is different from SVT in that the source comes from random points within the atria. These impulses then cause the atria to fibrillate (partial contraction) rapidly sometimes it could reach 400 heartbeats per minute. Some of these impulses could reach the ventricles hence making them increase the beats to between 160-180 beats.AF could be permanent or could appear in episodes in the same way as SVT (Daubert, et al., 2006). The condition is most common among the aging people but could also affect younger generation.
The differences between these life threatening cardiac arrhythmias and the sinus rhythm are mainly their varying force and increased heartbeats per minute. In the sinus rhythm, SA controls the beats while the same nodes are not controlling the beats in arrhythmias (Daubert, et al., 2006).
Daubert, J. P., Zareba, W., Hall, W. J., Schuger, C., Corsello, A., Leon, A. R., … & MADIT II study investigators. (2006). Predictive value of ventricular arrhythmia inducibility for subsequent ventricular tachycardia or ventricular fibrillation in Multicenter Automatic Defibrillator Implantation Trial (MADIT) II patients. Journal of the American College of Cardiology, 47(1), 98-107.
Thygesen, K., Alpert, J. S., & White, H. D. (2007). Universal definition of myocardial infarction. Journal of the American College of Cardiology, 50(22), 2173-2195.