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Background: Cardiovascular disease is common in diabetes, and is associated with activation of the renin-angiotensin system (RAS). Angiotensin-converting enzyme (ACE)2 is a recently described member of the RAS, and this study investigated whether ACE2 polymorphisms are associated with hypertension, left ventricular (LV) mass, and cardiac function in type 2 diabetes., Methods: Variants in ACE2 (rs1978124, rs2074192, rs4240157, rs4646156, rs4646188) were examined in 503 Caucasian subjects with type 2 diabetes. As ACE2 is located on the X chromosome, analyses were performed separately for men and women. Hypertension was defined by a history of hypertension, and/or antihypertensive medications or blood pressure (BP) >130/80 mm Hg. LV mass and systolic function (ejection fraction) were assessed by transthoracic echocardiography., Results: In men, hypertension was more prevalent with the ACE2 rs2074192 C allele (P = 0.023), rs4240157 G allele (P = 0.016) and rs4646188 T allele (P = 0.006). In men, the rs1978124 A allele was associated with a significantly lower ejection fraction compared to the G allele (62.3 ± 13.3 vs. 67.2 ± 10.9%, P = 0.002). This association remained significant after covariate adjustment for age, body mass index, hypertension, antihypertensive treatment, and BP. In women, the prevalence of hypertension was higher (P = 0.009) with the rs4240157 G allele, and the rs1978124 A allele was associated with significantly higher LV mass (P = 0.008)., Conclusions: In Caucasians with type 2 diabetes, genetic variation in ACE2 is associated with hypertension and reduced systolic function in men, and hypertension and increased LV mass in women.

Aims: Cardiac resynchronization therapy is showing benefits for an increasing number of indications but fails to predict response in up to 20-30% of subjects. Echocardiographically assessed dyssynchrony has been proposed as a potential stratifier but current methods are time-consuming and suffer poor reproducibility, thus limiting their clinical utility. This study compared the accuracy, time efficiency, and reproducibility of automated tissue synchronization imaging (Auto TSI) vs. established manual tissue velocity imaging (TVI) techniques for the assessment of intra-ventricular dyssynchrony in sinus and non-sinus rhythm., Methods and Results: Fifty consecutive stable systolic heart failure patients on optimal guideline-based medical therapy underwent intra-ventricular dyssynchrony assessment [time to peak velocity (Ts), septal to lateral delay (SLD), and dyssynchrony index (DI)] with TVI and Auto TSI techniques, enabling the assessment of agreement, time efficiency, and reproducibility. Statistical analyses included Pearson's correlation, Bland-Altman's statistics, and coefficient of reproducibility. There was excellent agreement between Auto TSI and TVI for the measurement of Ts [r=0.92, P<0.001, limits of agreement (LOA): -27.3 to 56.5 ms], SLD (r=0.94, P<0.001, LOA: -41 to 49 ms), and DI (r=0.89, P<0.001, LOA: -12.2 to 12.6 ms) which persisted irrespective of cardiac rhythm [Ts: sinus (n=32) r=0.93, P<0.001; non-sinus (n=18) r=0.91, P<0.001]. Automated TSI was more time efficient (3±1 vs. 14±2 min, P<0.001) and demonstrated superior reproducibility: intra-observer (5.5 vs. 9.6%) and inter-observer variability (9.5 vs. 13.4%)., Conclusion: Automated TSI enables rapid, reproducible intra-ventricular dyssynchrony assessment and overcomes some of the limitations of conventional techniques in sinus and non-sinus rhythm.