Regulation of the blood pressure and heart rate in diabetics

Cardiac autonomic neuropathy (CAN) is frequent in infraclinical stages. Its prognostic Value has been demonstrated. Cardiac autonomic neuropathy induc es different functional cardiac changes, especially a reduction in left ven tricular contractility and changes in ventricular repolarisation. It is als o associated with changes in the daily variations in blood pressure. The as sociation of CAN and silent myocardial ischaemia significantly worsens the prognosis. The investigation of CAN in the greatest number of diabetic patients is the refore justified. The study of heart rate Variations during deep respiratio n, active orthostatism or Valsalva manoeuvre, is still the reference. This method is simple, reproductible and may be carried out in the clinical sett ing in 10 to 15 minutes. The results must be strictly interpreted with rigo ur with respect to age. Orthostatic hypotension is a late sign of sympathet ic nervous system disease. Spectral analysis of blood pressure Variations o n orthostatism or the study of cutaneous blood flow during activating the s ympathetic system tests of greater sensitivity, should be developed. The demonstration of infraclinical CAN should lead to the careful use of dr ugs which may induce orthostatic hypotension and certain antiarrhythmics, t o search for disorders of ventricular repolarisation and for silent myocard ial ischaemia in diabetics with several risk factors.