Heart rate variability and diastolic dysfunction in patients with type 2 diabetes mellitus

Abstract

Cardiovascular autonomic neuropathy is a common form of autonomic dysfunction in diabetes mellitus (DM) and associates abnormalities in heart rate control and in vascular dynamics. This study evaluates the impact of diabetes mellitus on left ventricular diastolic dysfunction (LVDD) and heart rate variability in a group of type 2 diabetes mellitus without signs of cardiovascular disease. The study group consisted of 58 patients, aged 61 ± 8 years, diagnosed with type 2 DM. The subjects were selected from a series of 104 consecutive diabetic patients. All the subjects were on oral therapy or on diet for DM, and ECG was normal for all the subjects. The control group consisted of 45 healthy subjects, matched for age and sex. Heart rate variability was measured using a 24-h ECG monitoring system, and standard 2D and Doppler echocardiography was performed in all the subjects. There are significant differences between groups regarding disease duration, longer in patients with impaired relaxation (11.22 ± 9.17 vs. 8.31 ± 8.95 years), and disease control, worse in impaired relaxation group. Heart rate in impaired relaxation group is significantly higher than in controls, and higher, but not significantly, when compared with normal group (91 ± 10, vs. 88 ± 11 and 71 ± 11, respectively). Cardiac autonomic neuropathy was associated with LVDD in patients with type 2 DM, but without clinically manifest heart disease. Twenty-four-hour ECG monitoring and echocardiography can detect diabetic cardiomyopathy in early stages and should be performed in all subjects.

Poor glycemic control impacts linear and non-linear dynamics of heart rate in DM type 2

“…It has been shown that chronic hyperglycemia promotes progressive autonomic neural dysfunction in a manner that parallels the development of peripheral neuropathy control 32 . Corroborating with our study, Poanta et al 33 demonstrated a lack of autonomic control evaluated by HRV in subjects with T2DM without signs of cardiovascular disease.…”

Sex differences in baroreflex sensitivity, heart rate variability, and end organ damage in the TGR(mRen2)27 rat

“…Indeed, much accumulated evidence exists for an association between mean BP and cardiovascular risk factors. However, HRV and BPV, independent of the mean BP, have been shown to play a role in organ damage and have prognostic value (1,4,10,33,41,43). Several observations in this study suggest that differences in BP alone cannot fully account for differences between R2-M and R2-F. First, the nature of the relationship between HRV and SBP is very different between R2-M and R2-F.…”

“…Independent of baseline BP, changes in both HRV and BP variability are associated with indicators of end organ damage such as LVH, diastolic dysfunction, arterial stiffness, ventricular arrhythmia, and proteinuria as well as increased morbidity and mortality in hypertensive and diabetic patients (1,33,41) and in rodent pathological models (15). Our finding of strong correlations between HRV indexes and LVH in R2-M is consistent with these previous reports, specifically those examining the relationship between HRV and hypertrophic cardiomyopathy (3).…”

Chronotropic Incompetence During Exercise in Type 2 Diabetes: Aetiology, Assessment Methodology, Prognostic Impact and Therapy

“…Furthermore, Poanta et al [54] described a correlation between LV diastolic dysfunction and cardiac dysautonomia in T2DM patients. In that study, patients with restricted LV filling showed significant lower HR variability (a marker of cardiac autonomic function) than patients with non-restrictive LV filling.…”