Heart Rate During Exercise in Type 2 Diabetes

The study evaluated the influence of cardiac rehabilitation (CR) on heart rate variability (HRV) in men with coronary artery disease (CAD) with and without diabetes. Method: The study population included 141 male CAD patients prospectively and consecutively admitted to an outpatient comprehensive CR program. Twenty-seven patients with type-2 diabetes were compared with 114 males without diabetes. The participants performed a 45-min cycle ergometer interval training alternating 4-min workload and a 2-min active restitution three times a week for 8 weeks. The training intensity was adjusted so that the patient’s heart rate achieved the training heart rate calculated according to the Karvonen formula. At the baseline and after 8 weeks, all the patients underwent the HRV assessment. Results: HRV indices in the patients with diabetes were significantly lower as compared to the patients without diabetes in SDNN, TP, LF parameters, both at the baseline and after 8 weeks of CR. After 8 weeks of CR, a significant improvement of TP, SDNN, pNN50% and HF occurred in the patients without diabetes, whereas in the patients with diabetes only HF component improved significantly. Conclusions: As regards HRV indices, CR seems to be less effective in patients with CAD and type-2 diabetes.

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Effect of heart rate on left ventricular longitudinal myocardial function in type 2 diabetes mellitus

Cardiovascular Diabetology ◽

10.1186/s12933-021-01278-7 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Yuki Yamauchi ◽

Hidekazu Tanaka ◽

Shun Yokota ◽

Yasuhide Mochizuki ◽

Yuko Yoshigai ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Heart Rate ◽

Type 2 Diabetes Mellitus ◽

Myocardial Function ◽

Normal Subjects ◽

Left Ventricular ◽

High Heart Rate ◽

Lv Dysfunction

Abstract Background Left ventricular (LV) longitudinal myocardial dysfunction is considered a marker of preclinical LV dysfunction in patients with type 2 diabetes mellitus (T2DM). High heart rate (HR) is associated with cardiovascular outcomes, but the effect of HR on LV longitudinal myocardial function in T2DM patients is uncertain. Methods We studied 192 T2DM patients with preserved LV ejection fraction (LVEF), and 81 age-, sex-, and LVEF-matched healthy volunteers. HR was measured as the average HR during echocardiography, and high HR was defined as resting HR ≥ 70 beats/minute. LV longitudinal myocardial function was assessed as global longitudinal strain (GLS). The predefined cutoff for subclinical LV dysfunction was set at GLS < 18%. Results GLS in T2DM patients with high HR was significantly lower than that in T2DM patients with low HR (16.3% ± 4.2% vs. 17.8% ± 2.8%; P = 0.03), whereas GLS in normal subjects with high and low HR was similar (20.3 ± 1.7% vs. 20.3 ± 2.0%; P = 0.99). Multivariable logistic regression analysis showed that high HR (odds ratio: 1.04; 95% confidence interval: 1.01–1.07; P = 0.01) was independently associated with GLS < 18% in T2DM patients as well as HbA1c, T2DM duration, LVEF, body mass index, and mitral inflow E and mitral e’ annular velocity ratio. One sequential logistic model evaluating the associations between GLS < 18% and clinical variables in T2DM patients showed an improvement with the addition of LVEF and E/e’ (P < 0.001) and a further improvement with the addition of high HR (P < 0.001). Conclusion Compared with normal subjects, resting HR was associated with LV longitudinal myocardial function in asymptomatic T2DM patients with preserved LVEF. Our findings provide new insights on the management of T2DM patients.

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