Twenty-four hour Holter ECG in normocalcemic and hypercalcemic patients with hyperparathyroidism

PURPOSE

To investigate the occurrence of arrhythmias in patients with normocalcemic (NC) primary hyperparathyroidism (PHPT) compared to both hypercalcemic PHPT patients and control subjects by means of 24-h Holter ECG.

METHODS

Thirteen NCPHPT postmenopausal patients were enrolled and age-matched with 13 hypercalcemic PHPT patients and 13 controls. Every subject underwent basal ECG, 24-h Holter ECG and mineral metabolism biochemical evaluation.

RESULTS

PHPT patients had higher mean serum calcium levels compared to both NCPHPT and controls; there was no difference in mean serum calcium levels between NCPHPT and controls. Both NCPHPT and PHPT patients had significantly higher mean PTH levels compared with controls. There were no differences in ECG parameters between the three groups, except for QTc interval. PHPT patients had normal QTc interval values, but significantly shorter mean values compared with those of controls and NCPHPT patients. During 24-h Holter ECG recording, 100% of PHPT patients had supraventricular premature beats (SVPBs), compared to 46% of NCPHPT (p = 0.005) and to 53% of controls (p = 0.01). PHPT patients experienced ventricular premature beats (VPBs) (69.2%) vs 15% of NCPHPT patients (p = 0.01) and 23% of controls (p = 0.04). There was no difference between NCPHPT and controls subjects concerning occurrence of both VPBs and SVPBs.

CONCLUSIONS

NCPHPT patients did not experience an increased occurrence of arrhythmias compared to controls, while PHPT patients showed an increased occurrence compared to both controls and NCPHPT. Our findings are most probably related to the short QTc interval caused by hypercalcemia observed in PHPT patients, but not in NCPHPT.

Cardiovascular risk assessment by electrocardiographic Holter monitoring in patients with chronic hepatitis C

INTRODUCTION

Cardiovascular diseases are ranked as the third cause of mortality among people infected with hepatitis C virus (HCV), but the relationship of infection with cardiovascular risk remains disputable. We have focused on the comprehensive use of parameters obtainable during long-term electrocardiographic (ECG) Holter monitoring.

MATERIAL AND METHODS

Heart rate variability and turbulence (HRV and HRT), deceleration/acceleration capacity (DC/AC), corrected QT interval (QTc) and late potential (LP) were used. 36 persons were included, and 30 healthy subjects formed a control group. All were submitted to 24-hour Holter ECG-monitoring.

RESULTS

The studied groups were not statistically significantly different with regards to basic anthropometric parameters. Statistically significantly higher medium and maximum heart rhythm and aminotransferase activities were recorded in patients with hepatitis C. The HRV parameters r-MSSD, p50NN, HF, and absolute DC/AC values were significantly lower in the subjects with hepatitis C than those in the control group. The QTc interval, measured for nocturnal hours, was also significantly longer in that group. There were no differences in the albumin level or basic echocardiographic parameters, including left ventricle ejection fraction. Nor was there any difference in the HRT parameters, or LP. The most interesting observation was the positive correlation among the number of viral RNA copies and DC, and LF.

CONCLUSIONS

We confirmed the presence of autonomic disorders with prevalence of sympathetic system activity and prolonged QTc interval in patients with chronic hepatitis C. Those parameters significantly correlated with infection intensity. Our results suggest that HCV infection could be an independent cardiovascular risk factor, not associated with the lipid profile. Further prospective studies are needed.

The occurrence of atrial fibrillation in dialysis patients and its association with left atrium volume before and after dialysis

PURPOSE

Atrial fibrillation is a serious problem, especially in patients on dialysis. The prevalence of AF in this group of patients is higher than in general population and associated with increased mortality. The aim of this study was to assess the risk of the occurrence of atrial fibrillation related to intradialysis hypotension and left atrium volume enlargement associated with dialysis. The influence of dialysis session on: E/E', V LA, E/A, E', V RA and the width of inferior vena cava of RV was analyzed.

METHODS

This study included 40 patients on hemodialysis. Echocardiographic examination was performed to assess heart condition and function, the presence of LVH and systolic and diastolic function disturbances, LV mass, LA size, LAV, RAV, E/A, E', E/E, ejection fraction in all patients before and after dialysis. Moreover, all patients had ECG Holter continuously recording heart's rhythm before and after dialysis to assess the occurrence of atrial fibrillation related to dialysis session.

RESULTS

The analysis of differences in echocardiographic parameters before and after dialysis demonstrated significantly greater left atrium volume, right atrium volume, width of inferior vena cava and e' parameter before dialysis in comparison with post-dialysis state. Significantly higher incidence of AF after dialysis was seen. Volume of left atrium exceeding 32 mm (cutoff value) was observed significantly more often in patients before dialysis. No association was observed between left ventricle mass and left atrium volume.

CONCLUSIONS

The dialysis procedure may be a trigger for atrial fibrillation and thus AF preventive measures should be introduced in dialysis patients.

Autonomic dysfunction is associated with brief episodes of atrial fibrillation in type 2 diabetes

BACKGROUND AND AIMS

This study aimed to investigate the relationship between asymptomatic episodes of atrial fibrillation (AF) and abnormalities of the autonomic nervous system in type 2 diabetic patients who did not have evidence of atrial fibrillation at baseline.

METHODS AND RESULTS

In a multicentric cross-sectional controlled study, 1992 patients with type 2 diabetes were screened. All underwent ambulatory ECG recording for 48-hour at 3, 6, 9, and 12months. Heart rate variability (HRV) was used as indicator of autonomic activity. One hundred seventy-six diabetics with silent atrial fibrillation episodes (SAFE group) and 288 without silent atrial fibrillation (non-SAFE group) were enrolled. These selected diabetics were matched on clinical and anthropometric data to 120 control subjects without diabetes of the control group. HRV analysis evidenced that LF/HF ratio was significantly higher in the SAFE group than in the non-SAFE group (P<0.05) in the whole period of HM analysis. AF absolute burdens were positively correlated with LF/HF ratio (r=0.31, P<0.001). Multiple regression analysis showed that LF/HF ratio was an independent determinant of AF episodes.

CONCLUSIONS

This study originally showed a strong relationship between autonomic dysfunction and silent atrial fibrillation in type 2 diabetes.