DR ZIAD NOFAL CARDIOLOGIST DAMASCUS HOSPITAL

 Involvement of peripheral and autonomic nervous systems  Most common complication of diabetes  Underdiagnosed and Undertreated  Substantial morbidity/mortality (CAN)

 Least recognized and understood complications of diabetes.  Can involve the entire autonomic nervous system (ANS)  May be either clinically evident or subclinical

DDistal symmetric polyneuropathy FFocal Mononeuropathies AAutonomic neuropathy PPolyradiculopathies MMononeuropathy multiple

 CAN is defined as the impairment of autonomic control of the cardiovascular system in the setting of diabetes after exclusion of other causes.

 Cardiac denervation can occur in diabetic patients with advanced autonomic neuropathy. It is characterized by a  fixed heart rate, in the range of 80 to 90 beats per minute, and is associated with painless myocardial infarction and sudden death.  QT prolongation.

 Most studied and clinically important  Increased CV mortality  damage to the autonomic nerve fibers that innervate the heart and blood vessels, resulting in abnormalities in heart rate control and vascular dynamics.

1. Perioperative unstability 2. Resting tachycardia 3. Loss of reflex heart rate variations 4. Hypertension Exercise intolerance 5. Orthostatic hypotension 6. Postprandial hypotension 7. Silent myocardial ischaemia 8. Left ventricular dysfunction and hypertrophy 9. QT interval prolongation 10. Impaired baroreflex sensitivity 11. Non-dipping, reverse dipping 12. Sympathovagal imbalance 13. Dysregulation of cerebral circulation 14. Sympathetically mediated vasodilation of coronary vessels 15. Arterial stiffness 16. Peripheral vascular function 17. Peripheral blood flow and warm skin 18. Arteriovenous shunting and swollen veins 19. Venous pressure Leg and foot oedema

 Clinically, the impairment in autonomic function is associated with  resting tachycardia  exercise intolerance  orthostatic hypotension  intraoperative cardiovascular instability  silent cad  increased mortality

1. Tachycardia (HR >100 bpm) 2. Decreased exercise tolerance 3. Orthostasis (>20mmHg fall in systolic BP upon standing without compensationHR) 4. Cardiac denervation syndrome= SILENT MI 5. Paradoxic supine or nocturnal hypertension 6. Intraoperative and perioperative cardiovascular instability 7. Left ventricular diastolic dysfunction

1. Decreased thermoregulation 2. Decreased sweating 3. Altered blood flow 4. Impaired vasomotion 5. Edema

1. Exercise intolerance is usually due to impaired augmentation of cardiac output resulting from inadequate sympathetic modulation. 2. Sympathetic tone may be increased during the day and parasympathetic tone decreased at night, which may predispose to nocturnal arrhythmogenesis. 3. prevalence of QT prolongation was 16 percent overall (11 percent in men, 21 percent in women. 4. fixed heart rate in the range of 80 to 90 beats per minute, and is associated with painless myocardial infarction and sudden death.

 There is day-to-day variability of symptoms that may be exacerbated by insulin therapy, which can provoke hypotension in both diabetic and nondiabetic patients with autonomic failure.  In occasional patients, supine and standing systolic blood pressures may fall profoundly after meals (postprandial hypotension)

 A posture-induced tachycardia without a fall in blood pressure can result in similar symptoms as are experienced in postural hypotension. The etiology is poorly understood.

 poor glucose control  elevated triglyceride levels  elevated body mass index  smoking  hypertension

 Nuclear Stress test  ACE I, BB, Antioxidants (Alpha-lipoic acid)  Supportive garments for orthostatic hypotension  Clonidine, fludrocortisone, midodrine, octreotide?

 Making changes in posture slowly."  Tensing the legs by crossing them while actively standing on both legs. In one report of patients with autonomic neuropathy, this procedure raised the cardiac output by 16 percent and the systemic blood pressure by 13 percent. It can therefore minimize postural symptoms.  Performing dorsiflexion of the feet or handgrip exercise before standing.