Assessment of fragmented QRS formation and its relationship with left ventricular hypertrophy in nonhypertensive acromegaly patients

Background/aim: It is known that the presence of fragmented QRS (fQRS) on electrocardiography (ECG) is associated with cardiovascular events. The aim of this study was the evaluation of fQRS formation and its relationship with the left ventricular hypertrophy (LVH) parameters in acromegaly patients. Materials and methods: In total, 47 previously diagnosed with non-hypertensive acromegaly patients and 48 control subjects were included in the study. ECG and transthoracic echocardiography (TTE) were performed for each participant. Acromegaly patients were divided into two groups according to the fQRS formation on the ECG. Left ventricular wall thicknesses, and left atrial diameter (LAD), left ventricular mass (LVM), left ventricular mass index (LVMi), and relative wall thickness (RWT) were obtained. Results: In control group 5 (10.4%) and in acromegaly group 17 (36.2%) patients had fQRS on ECG (p = 0.003). LAD [36.0 (34.0­38.0) vs. 38.0 (35.0­41.0) mm, p < 0.001], LVM [155.27 ± 27.00 vs. 173.0 (153.0­235.0) g, p < 0.001], LVMi [83.12 ± 13.19 vs. 92.0 (83.0­118.0) g/m², p < 0.001] and RWT [0.39 ± 0.03 vs. 0.43 (0.41­0.45), p = 0.001] were significantly higher in patients with acromegaly. Disease duration was significantly higher (11.59 ± 1.3 vs. 8.2 ± 1.8 years, p < 0.001) in the fQRS (+) group. LAD [41.0 (39.0­42.5) vs. 37.0 (34.7­38.0) mm, p < 0.001], LVM [219.0 (160.5­254.5) vs. 164.0 (153.0­188.0) g, p = 0.017], LVMi [117.0 (92.5­128.5) vs. 86.0 (82.0­100.2) g/m², p = 0.013] and RWT [0.44 (0.42­0.49) vs. 0.43 (0.40­0.44), p = 0.037] were significantly higher in fQSR (+) acromegaly patients. In multivariate logistic regression analysis, disease duration (odds ratio: 10.05, 95% CI: 1.099­92.012, p = 0.041) and LAD (odds ratio: 2.19, 95% CI: 1.030­4.660, p = 0.042) were found to be the independent predictors of fQRS formation. Conclusion: The results of our study revealed that fQRS (+) acromegaly patients had increased LVH parameters compared to fQRS (-) patients.

Assessment of cardiac autonomic functions by heart rate recovery, heart rate variability and QT dynamicity parameters in patients with acromegaly.

Cardiovascular complications are the most common causes of morbidity and mortality in acromegaly. However, there is little data regarding cardiac autonomic functions in these patients. Herein, we aimed to investigate several parameters of cardiac autonomic functions in patients with acromegaly compared to healthy subjects. We enrolled 20 newly diagnosed acromegalic patients (55% female, age:45.7 ± 12.6 years) and 32 age- and gender-matched healthy subjects. All participants underwent 24 h Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting 1st, 2nd and 3rd minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV) and QT dynamicity analysis. Baseline characteristics were similar except diabetes mellitus and hypertension among groups. Mean HRR1 (29.2 ± 12.3 vs 42.6 ± 6.5, p = 0.001), HRR2 (43.5 ± 15.6 vs 61.1 ± 10.8, p = 0.001) and HRR3 (46.4 ± 16.2 vs 65.8 ± 9.8, p = 0.001) values were significantly higher in control group. HRV parameters as, SDNN [standard deviation of all NN intervals] (p = 0.001), SDANN [SD of the 5 min mean RR intervals] (p = 0.001), RMSSD [root square of successive differences in RR interval] (p = 0.001), PNN50 [proportion of differences in successive NN intervals >50 ms] (p = 0.001) and high-frequency [HF] (p = 0.001) were significantly decreased in patients with acromegaly; but low frequency [LF] (p = 0.046) and LF/HF (p = 0.001) were significantly higher in acromegaly patients. QTec (p = 0.009), QTac/RR slope (p = 0.017) and QTec/RR slope (p = 0.01) were significantly higher in patients with acromegaly. Additionally, there were significant negative correlation of disease duration with HRR2, HRR3, SDNN, PNN50, RMSSD, variability index. Our study results suggest that cardiac autonomic functions are impaired in patients with acromegaly. Further large scale studies are needed to exhibit the prognostic significance of impaired autonomic functions in patients with acromegaly.