Association between retinopathy, microalbuminuria and coronary perfusion in young patients with type 1 diabetes mellitus

Background: In patients with type 1 diabetes mellitus (DM) impairment of the coronary circulation has been observed. This phenomenon could be ascribed to the existence of a specific cardiomyopathy. Disturbances in other microcirculation beds - renal and ocular - are mirrored by microalbuminuria and retinopathy, respectively. The association between coronary microvascular dysfunction and the presence of microalbuminuria and retinopathy is not clear. Recognition of the interrelationships between microalbuminuria, retinopathy and the impairment of coronary circulation could allow for a simple estimation of coronary perfusion in these patients. Aim: To assess coronary blood flow velocity in young patients with type 1 DM using transoesophageal Doppler echocardiography with dipyridamole and to analyse the possible relationship between the impairment of coronary flow and retinopathy as welt as microalbuminuria. Methods: The study group consisted of 36 patients, aged from 18 to 35 (mean: 25 5) years with type 1 DM lasting from 8 to 27 years. Diabetes was the only disease and none of the patients had any history of cardiovascular diseases or any abnormalities in physical examination. The control group consisted of 23 age-matched healthy volunteers. All subjects underwent transoesophageal echocardiography with dipyridamole to assess coronary flow velocity reserve (CFVR). Results: In the study group CFVR and maximal flow velocity after dipyridamole were significantly decreased (2.4 +/- 0.6 vs. 3.4 +/- 0.7; p <0.001 and 125.7 +/- 31.4 vs. 168.00 +/- 12.9 cm/s; p <0.001, respectively). The basal flow velocity was comparable in both groups (55.9 +/- 14.6 vs. 52.2 +/- 11.6 cm/s; p=0.32). Decrease in CFVR in the study group was associated with a smaller increase in coronary flow velocity after dipyridamole challenge. There was no relationship between coexisting microalbuminuria, retinopathy and the CFVR values. Conclusions: in young patients with type 1 DM, without any clinical cardiovascular abnormalities, decreased coronary perfusion is observed. The presence of microalbuminuria or retinopathy is not associated with the alterations in coronary perfusion.