Tachycardia in Diabetic Patients

In diabetic patients the body cannot break down food into glucose and carry it throughout the body as they lack insulin to turn glucose into energy. The blood glucose levels rise and over time can damage the blood vessels and nerves that control the heart. The longer a person has diabetes, the higher his chances for developing heart disease are. Moreover, blood vessels in diabetics are more susceptible to other risk factors, such as high blood pressure, high cholesterol and smoking, and as a result diabetic patients may develop cardiac rhythm disorders associated with diabetes itself as well as with other concomitant conditions – ischemic heart disease, arterial hypertension, etc. The character of rhythm disorders in diabetics is fairly different and not all of them require medical interference. Many of these disorders remain unchanged throughout life, but some of them can progress and lead to severe complications therefore require urgent medical intervention. Not all cardiac rhythm and conduction disorders may clinically manifest and therefore can be spotted only during electrocardiographic examination. At the same time the disorders can manifest with different symptoms, which patients not always associate with arrhythmias. Thus, besides typical sensations of erratic heartbeat, rhythm disorders may have other clinical manifestations:

• Palpitations (fluttering in chest)
• Dizziness
• Lightheadedness
• Sinking heart
• Shortness of breath
• Sudden weakness
• Faintness.

Sometimes rhythm disorders are discovered when taking pulse with a complete lack of subjective perceptions. In all the above mentioned cases reference to a doctor is required. Only thorough examination and sound medical judgment will allow your doctor to choose a proper treatment. A number of symptoms, especially among young patients with chronic diabetes, can be due to diabetic autonomic neuropathy (DAN)– the least recognized complication of diabetes, when there is diffused and widespread damage to peripheral and autonomic nerves, as well as small vessels. When diabetic neuropathy affects the autonomous nervous system, it can damage other body systems, including cardiovascular and neurovascular ones, and impair metabolic functions such as glucose counter-regulation. This leads to cardiac autonomic neuropathy (CAN) - damage of the autonomic nerve fibers that innervate blood vessels and the heart, resulting in heart rate control abnormalities and vascular dynamics. It represents a significant risk of cardiac arrhythmias and sudden death. In simple words, CAN is a diabetes complication at which cardiac nerves are damaged due to chronic high blood sugar. It is these nerves damage that is responsible for heart rhythm disorders. The symptoms:

• sinus tachycardia even at rest with fixed heart rate 90-100 up to 130 beats per minute
• respiration not affecting heart rate variability (normally heartbeat rate decreases with deep breathing)
• require special examination to assess nervous control of cardiac function and prophylactic use of drugs to prevent neuropathy progressing.

Damage to sensory nerve fibers leads not just to tachycardia, but to atypical ischemic heart disease progression as well. Diabetic patients may not have sensation of ischemic pain, which delays visiting a doctor and can even suffer silent myocardial infarction, which can be life threatening. To sum up, diabetic patients must consult their doctor if stable tachycardia is present in order to timely prevent the progression of diabetic cardiovascular autonomic neuropathy.