Presence of micro- and macroalbuminuria and the association with cardiac mechanics in patients with type 2 diabetes.

Aims: Albuminuria-a marker of generalized vascular dysfunction-is a strong predictor of heart failure in patients with type 2 diabetes which may be caused by concomitant myocardial dysfunction reflecting the same underlying pathogenesis.

Methods and results: We included 915 patients with type 2 diabetes from two secondary care centres and stratified according to albuminuria status in normo-, micro-, and macroalbuminuria. We performed comprehensive echocardiography including conventional imaging, tissue Doppler imaging, and 2D speckle tracking. Cardiac remodelling occurred in patients with increasing left ventricular (LV) mass index and LV wall thicknesses with increasing severity of albuminuria. Diastolic measures worsened across groups of albuminuria severity (normo-, micro-, and macroalbuminuria, respectively): septal e' velocity [mean: 6.9 cm/s (SD 1.9), 6.4 (1.7), and 5.9 (1.7), P < 0.001], septal E/e' (median: 10.6 [interquartile range: 8.9-13.2], 12.1 [10.3-14.8], and 12.7 [10.4-16.6], P < 0.001), and left atrial volume index (24.3 mL/m2 [19.1-29.9], 25.7 [20.0-31.6], and 29.0 [22.2-34.9], P < 0.001) In contrast, systolic measures were only impaired in patients with macroalbuminuria: global longitudinal strain (GLS): [-14.6% (2.7) in normo- and -13.3 (2.9) in macroalbuminuria, P < 0.001] and GLS rate [mean: -0.79 s-1 (0.17) in normo- and -0.72 (0.16) in macroalbuminuria, P = 0.001]. The findings persisted in subgroup analyses of patients without known coronary heart disease and with normal ejection fraction and in multivariable adjusted analyses.

Conclusion: In patients with type 2 diabetes, microalbuminuria is associated with decreased diastolic function whereas decreased systolic function was only associated with macroalbuminuria supporting the notion of similar pathogenic mechanisms of albuminuria and impaired myocardial function.