The Heart's Function as a Pump Assessed via Impedance Cardiography and the Autonomic System Balance in Patients with Early-Stage Acromegaly

BACKGROUND

Acromegaly is a rare, chronic disease that involves structural and functional abnormalities of the cardiovascular system. Acromegaly likely affects interactions between the cardiovascular system and the autonomic nervous system (ANS). Therefore, assessing the relationship between sympathetic-parasympathetic balance by analyzing heart rate variability (HRV) and the hemodynamic profile via impedance cardiography (ICG) may be useful in learning the exact nature of interactions between the ANS and the cardiovascular system. The purpose of this study was to assess a possible association between HRV and ICG-based parameters of cardiac function in patients newly diagnosed with acromegaly.

METHODS

This observational cohort study was conducted on 33 patients (18 men, mean age of 47 years) newly diagnosed with acromegaly and no significant comorbidities. A correlation analysis (Spearman's rank coefficient R) of the parameters assessed via ICG and the HRV assessed via 24 h ambulatory electrocardiography was performed. ICG assessments included the following parameters: stroke volume index (SI), cardiac index (CI), acceleration index (ACI), velocity index (VI), and Heather index (HI). The analysis of HRV included both time-domain parameters (pNN50, SDNN, SDSD, rMSSD) and frequency-domain parameters (total power (TP) and its individual frequency bands: low-frequency (LF day/night), high-frequency (HF day/night), and the LF/HF ratio (day/night)).

RESULTS

Frequency-domain HRV analysis showed the following correlations: (1) lower nighttime LF values with higher ACI (R = -0.38; p = 0.027) and HI (R = -0.46; p = 0.007) values; (2) higher nighttime HF values with higher ACI (R = 0.39; p = 0.027) and HI (R = 0.43; p = 0.014) values; (3) lower nighttime LF/HF values with higher ACI (R = -0.36; p = 0.037) and HI (R = -0.42; p = 0.014) values; (4) higher nighttime TP values with higher SI values (R = 0.35; p = 0.049). Time-domain parameters of HRV showed a significant correlation only between the nighttime values of SDSD and SI (R = 0.35; p = 0.049) and between the daytime and nighttime values of SDNN and HR (R = -0.50; p = 0.003 and R = -0.35; p = 0.046). In multivariate regression, only ACI was revealed to be independently related to HRV.

CONCLUSIONS

In patients newly diagnosed with acromegaly, the relationship between the sympathetic-parasympathetic balance assessed via HRV and the hemodynamic profile assessed via ICG was revealed. Better function of the left ventricle was associated with a parasympathetic shift in the autonomic balance.

The patient's sex determines the hemodynamic profile in patients with Cushing disease

Background

Cushing disease (CD) may lead to accelerated cardiovascular remodeling and increased mortality. There are suspected differences in the mechanism of cardiovascular dysfunction between males and females with CD. The purpose of this study was to assess the effect of patient sex on the hemodynamic profile assessed via impedance cardiography and echocardiography in patients newly diagnosed with CD.

Material and methods

The 54 patients newly diagnosed with CD (mean age 41 years; 77.8% of females) who were included in this prospective clinical study underwent impedance cardiography to assess specific parameters (including systemic vascular resistance index [SVRI], total arterial compliance index [TACI], Heather index [HI], stroke index [SI], cardiac index [CI], velocity index [VI], and acceleration index [ACI]) and transthoracic echocardiography to assess heart chamber diameters and left ventricular systolic and diastolic function.

Results

Males with CD exhibited higher afterload, with higher SVRI (3,169.3 ± 731.8 vs. 2,339.3 ± 640.8 dyn*s*cm-5*m² in males and females, respectively; p=0.002), lower TACI (0.80 ± 0.30 vs. 1.09 ± 0.30 mL/mmHg*m2; p=0.008), and lower hemodynamic parameters of left ventricular function, with lower HI (9.46 ± 2.86 vs. 14.1 ± 5.06 Ohm/s2; p=0.0007), lower VI (35.1 ± 11.9 vs. 44.9 ± 13.1 1*1000-1*s-1; p=0.009), lower SI (36.5 ± 11.7 vs. 43.6 ± 9.57 mL/m2; p=0.04), lower CI (2.36 ± 0.46 vs. 3.17 ± 0.76 mL*m-2*min-1; p=0.0009), and lower ACI (50.4 ± 19.8 vs. 73.6 ± 25.0 1/100/s2; p=0.006). There were no significant differences between the sexes in left ventricular systolic or diastolic function assessed by echocardiography.

Conclusion

In comparison with females with CD, males with CD have a less favorable hemodynamic profile, with higher afterload and worse left ventricular function. Sex differences in cardiovascular system function should be taken into consideration in designing personalized diagnostic and therapeutic management of patients with CD.

Value of Left Atrial Strain in Predicting Recurrence after Atrial Fibrillation Ablation

This study tested the relationship between left atrial (LA) function parameters and the results of pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Consecutive patients undergoing PVI for the first time between 2019 and 2021 were included. Patients underwent radiofrequency ablation using contact force catheters and an electroanatomical system. Follow-up consisted of ambulatory visits/televisits and 7-day Holter monitoring (at 6 and 12 months after ablation). On the day of ablation, all patients underwent transesophageal and transthoracic echocardiography with LA strain analysis. The primary endpoint was atrial tachyarrhythmia recurrence during the follow-up period. Of 221 patients, 22 did not meet the echocardiographic quality criteria, leaving 199 patients. The median follow-up period was 12 months, and 12 patients were lost to follow-up. Recurrences were observed in 67 patients (35.8%) after a mean of 1.06 procedures per patient. The patients were divided into a sinus rhythm (SR, n = 109) group and an AF (n = 90) group based on their cardiac rhythm at the time of echocardiography. In the SR group, univariable analysis showed that LA reservoir strain, LA appendage emptying velocity (LAAV), and LA volume index predicted AF recurrence, with only LAAV being significant in the multivariable analysis. In AF patients, univariable analysis revealed no LA strain parameters predicting AF recurrence.

Increased Thoracic Fluid as the Most Distinctive Cardiovascular Hemodynamic Alteration in Men with Prolactinoma

Hyperprolactinemia in males with prolactin-secreting adenomas, or prolactinomas, may be associated with endothelial dysfunction and co-existing cardiovascular risk factors. As a noninvasive technique of assessing cardiac function, impedance cardiography (ICG) may be useful in the early detection of hemodynamic dysfunction. The aim of the present study was to analyze and compare the hemodynamic profiles of patients with prolactinoma versus controls. A total of 20 men with prolactinoma (PR group) (mean age 43 years) and 20 men from the control group (CG) were evaluated in this prospective, observational comparative clinical study. The study subjects were propensity score-matched in terms of clinical characteristics—age, mean blood pressure [MBP], arterial hypertension [AH] rates, and body mass index [BMI]. ICG assessments of hemodynamic profiles were conducted with the use of a Niccomo™ device and included stroke volume index (SI), cardiac index (CI), systemic vascular resistance index (SVRI), velocity index (VI), acceleration index (ACI), Heather index (HI), and thoracic fluid content (TFC). AH was well-controlled in both study groups (116/76 mmHg PR vs. 119/76 mmHg CG). In comparison with CG patients, ICG revealed PR group patients to have higher rates of high thoracic fluid content (TFC) (>35 1/kOhm; p = 0.035) and lower SI values (<35 mL/m2, p = 0.072). There was a convergent tendency towards lower values of other cardiac function parameters (SI, CI, VI, ACI, and HI). Prolactinoma-associated endocrine abnormalities are related to hemodynamic profile alterations, including higher rates of increased TFC and the risk of worsened cardiac function.

Left atrial function parameters as predictors of atrial fibrillation recurrence after pulmonary vein isolation

Background

The aim of the study was to test the relationship between left atrial (LA) function parameters and the results of the pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF).

Patients and methods

Consecutive patients undergoing first time PVI in years 2019–2021 were qualified to the study. The patients underwent radiofrequency ablation using contact-force catheters and electroanatomical system. LA pressure was measured directly just after transseptal puncture. Follow-up was based on ambulatory visits/televisits and 7-day holter monitoring (6 and 12 month after ablation). On the day of ablation all the patients underwent transesophageal and transthoracic echocardiography. The primary endpoint was any atrial tachyarrhythmia recurrence during follow-up period.

Results

A total of 210 patients were included in the study. Median of follow-up was 12 months, AF recurrence was observed in 71 patients (33.8%) after mean of 1.03 procedures per patient. In univariate Cox regression analysis several echocardiographic parameters were significant predictors of AF recurrence after catheter ablation: left and right atrial area, LA volume, average e' and average E/e' values, LA reservoir strain, LA conduit strain, LA appendage emptying velocity. AF recurrence was also predicted by mean LA pressure, age, body mass index and calculated eGFR. Interestingly, LA contraction strain and LA emptying fraction were not predictors of results of AF ablation. In multivariate Cox regression analysis (that included all parameters significant in univariate analysis) LA reservoir strain (hazard ratio (HR) 1.076, 95% confidence interval (CI) 1.014–1.141; p=0.014) and LA appendage emptying velocity (HR 0.968, 95% CI 0.947–0.988; p=0.002) were significant predictors of AF ablation results.

Conclusions

LA reservoir strain and LA appendage emptying velocity are predicting factors of AF ablation results. LA contraction strain and LA emptying function were not predictors of effective AF ablation.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Statutory Grant of Military Institute of Medicine

Associations between Heart Rate Variability Parameters and Hemodynamic Profiles in Patients with Primary Arterial Hypertension, Including Antihypertensive Treatment Effects

Background: Autonomic nervous system (ANS) dysfunction is an important factor in the development and progression of arterial hypertension (AH) and may produce adverse hemodynamic sequelae. ANS function can be evaluated by analyzing heart rate variability (HRV). The purpose of this study was to assess the possible correlation between HRV and the hemodynamic profile of AH patients, including antihypertensive treatment effects after 12 months. Methods: The study was conducted on 144 patients with uncomplicated AH. The hemodynamic profile was assessed via echocardiography and impedance cardiography (ICG). The analyzed HRV parameters included SDNN, rMSSD, pNN50, low frequency (LF, 0.05–0.15 Hz), high frequency (HF, 0.15–0.4 Hz), total power (TP, the variance of all NN intervals), and the day, night, and 24-h low-to-high frequency ratios (LF/HF). Results: Analysis showed various correlations of HRV parameters both with arterial blood pressure and with the hemodynamic profile assessed via echocardiography and ICG. The HRV parameters of increased ANS activity showed a correlation with improved left ventricle function (LV) and lower LV afterload. Conclusions: Effective antihypertensive treatment demonstrated beneficial effects on both the ANS balance and the hemodynamic profile.

Prolactinoma and cardiovascular diseases – an interdisciplinary problem

Prolactin-secreting pituitary tumour is a rare disease, in which excess prolactin causes significant functional and constitutional disorders of the whole body. Hyperprolactinaemia is associated with changes in body composition and metabolic disorders. The long-term prognosis and quality of life in patients with prolactinoma are mainly influenced by cardiovascular disorders, which, if left untreated, increase the cardiovascular risk and limit the treatment options for secondary organ complications. Cardiovascular mortality in patients with prolactinoma is several times higher than in the general population. Early diagnosis of prolactin-releasing pituitary tumour and a thorough morphological and functional cardiovascular assessment at each stage of the disease are necessary for risk stratification. Patients with prolactinoma should be put on combined treatment based on both serum prolactin control, and reduction of cardiovascular risk factors. Normalisation of prolactin levels and reduction of the tumour mass, achieved mainly through effective pharmacotherapy, reduce mortality and the risk of cardiovascular complications; therefore, the earliest possible diagnosis of prolactin pituitary tumour and implementation of appropriate treatment as well as active diagnosis and therapy of coexisting organ complications should be set as a goal in these patients. It seems that a thorough cardiological assessment of patients with prolactinoma should be obligatory, regardless of their age or the time of diagnosis. The aim of this study was to present the complexity of clinical problems in patients with prolactin secreting pituitary tumours, who require special interdisciplinary care.

Cardiovascular risk in patients with Cushing’s disease – an interdisciplinary problem

Cushing’s disease is a chronic endogenous hypercortisolaemia associated with overproduction of adrenocorticotropic hormone by a pituitary adenoma, leading to multiple systemic complications that significantly increase morbidity and mortality, as well as reduce the quality of life as a result of prolonged tissue exposure to excess cortisol. Hypercortisolaemia in Cushing’s disease is associated with significant functional and constitutional disorders of the entire body. The consequences of chronic hypercortisolaemia include haemodynamic disorders associated with excessive vascular contraction and increased blood pressure, obesity, carbohydrate metabolism disorders, dyslipidaemia, and coagulopathies, which may contribute to significant cardiovascular remodelling. Cardiovascular disorders have a particular impact on long-term prognosis and quality of life in Cushing’s disease. If left untreated, Cushing’s disease significantly increases the cardiovascular risk and limits the treatment options for secondary organ complications. Cardiovascular mortality (myocardial infarction, heart failure, stroke) is several times higher in patients with Cushing’s disease than in the general population. Early diagnosis of the corticotropic pituitary tumour, as well as a thorough morphological and functional cardiovascular assessment seem essential in risk stratification. Normalisation of cortisol levels after combined neurosurgical and/or pharmacological treatment reduces mortality and the risk of cardiovascular and respiratory complications. The aim of this study is to present the complexity of clinical problems in patients with Cushing’s disease, who are in a particular need of interdisciplinary care.

Cushing's Disease: Assessment of Early Cardiovascular Hemodynamic Dysfunction With Impedance Cardiography

BACKGROUND

Cushing's disease is a rare condition associated with a high cardiovascular risk and hypercortisolemia-related hemodynamic dysfunction, the extent of which can be assessed with a noninvasive method, called impedance cardiography. The standard methods for hemodynamic assessment, such as echocardiography or ambulatory blood pressure monitoring may be insufficient to fully evaluate patients with Cushing's disease; therefore, impedance cardiography is being currently considered a new modality for assessing early hemodynamic dysfunction in this patient population. The use of impedance cardiography for diagnosis and treatment of Cushing's disease may serve as personalized noninvasive hemodynamic status assessment and provide a better insight into the pathophysiology of Cushing's disease. The purpose of this study was to assess the hemodynamic profile of Cushing's disease patients and compare it with that in the control group.

MATERIAL AND METHODS

This observational prospective clinical study aimed to compare 54 patients with Cushing's disease (mean age 41 years; with 64.8% of this population affected with arterial hypertension) and a matched 54-person control group (mean age 45 years; with 74.1% of this population affected with arterial hypertension). The hemodynamic parameters assessed with impedance cardiography included the stroke index (SI), cardiac index (CI), systemic vascular resistance index (SVRI), velocity index (VI), (ACI), Heather index (HI), and thoracic fluid content (TFC).

RESULTS

The Cushing's disease group was characterized by a higher diastolic blood pressure and a younger age than the control group (82.9 vs. 79.1 mmHg, p=0.045; and 41.1 vs. 44.9 years, p=0.035, respectively). Impedance cardiography parameters in the Cushing's disease group showed: lower values of SI (42.1 vs. 52.8 ml/m²; p ≤ 0.0001), CI (2.99 vs. 3.64 l/min/m²; p ≤ 0,0001), VI (42.9 vs. 52.1 1/1000/s; p=0.001), ACI (68.7 vs. 80.5 1/100/s²; p=0,037), HI (13.1 vs. 15.2 Ohm/s²; p=0.033), and TFC (25.5 vs. 27.7 1/kOhm; p=0.006) and a higher SVRI (2,515 vs. 1,893 dyn*s*cm^-5*m²; p ≤ 0.0001) than those in the control group.

CONCLUSIONS

Cushing's disease is associated with significantly greater vasoconstriction and left ventricular systolic dysfunction. An individual assessment with impedance cardiography may be useful in Cushing's disease patients in order to identify subclinical cardiovascular complications of chronic hypercortisolemia as potential therapeutic targets.

Acromegaly: The Research and Practical Value of Noninvasive Hemodynamic Assessments via Impedance Cardiography

BACKGROUND

Arterial hypertension (AH) that accompanies acromegaly (AC) may lead to cardiovascular dysfunction. Such consequences may be detected with impedance cardiography (ICG), which is a noninvasive method of hemodynamic assessment. Early detection of subclinical hemodynamic alterations in AC patients may be crucial for optimizing treatment and preventing cardiovascular remodeling. The purpose of this study was to identify the hemodynamic parameters of the cardiovascular system that differentiate patients with AC from those in the control group (CG), with a particular emphasis on potential targets for medical therapy.

METHODS

This observational, prospective, clinical study involved a comparative analysis of 33 AC patients with no significant comorbidities and the controls selected via propensity score matching based on a set of baseline characteristics (age, sex, body mass index, mean blood pressure [MBP]), with comparable proportions of AH patients. The assessed hemodynamic parameters included the stroke volume index (SI), cardiac index, systemic vascular resistance index, velocity index (VI), acceleration index, Heather index (HI), and thoracic fluid content (TFC).

RESULTS

Both the AC group and the CG had well-controlled AH (mean blood pressure of 121/77 mmHg and 119/76 mmHg, respectively). In terms of baseline characteristics, the AC group was characterized by a higher hear rate and lower creatinine levels than the CG (76.2 bpm vs. 66.8 bpm [p = 0.001] and 0.755 mg/dL vs. 0.850 mg/dL [p = 0.035], respectively). ICG assessment of AC patients and CG patients showed the former to have higher heart rates (73.5 bpm vs. 65.2 bpm; p = 0.003), lower SI (43.8 mL/m² vs. 53.4 mL/m²; p = 0.0001), lower VI (42.1 1/1000/s vs. 49.3 1/1000/s; p = 0.037), lower HI (8.49 Ohm/s² vs. 13.4 Ohm/s², p ≤ 0.0001), and higher thoracic fluid content (TFC) (38.4 1/kOhm vs. 28.1 1/kOhm; p ≤ 0.0001), respectively.

CONCLUSIONS

Even with well-controlled hypertension, AC is associated with a high TFC, increased heart rate, and decreased indices of cardiac contractility. Hemodynamic changes in AC patients may be detected with the modern, noninvasive diagnostic tool, ICG.

Assessment of heart rate variability parameters in the age subgroups of patients with arterial hypertension

Age is one of the main known risk factors for cardiovascular diseases. The ageing of the body and arterial hypertension are associated with progressive dysfunction of the autonomic nervous system, which may be one of the mechanisms underlying an increased cardiovascular risk. The aim of the paper was to assess heart rate variability parameters in the age subgroups of patients with arterial hypertension. The heart rate variability parameters were compared in a total of 139 patients with untreated arterial hypertension (mean age 45.2 ± 10.5 years, men – 69% of the study group) in the following subgroups distinguished by age: ≥45 years (n = 72) and <45 years (n = 67). A temporal analysis of the heart rate variability parameters in 24-hour Holter ECG (SDNN, rMSSD, pNN50) was conducted for 24 hours, and for the day and night periods. In addition, a spectral analysis (LF, HF, TP, LF/HF ratio) was performed. The recorded values of SDNN, rMSSD, pNN50, TP as well as night-time HF were lower in the group of patients aged ≥45 years compared to the younger group. The results confirm that in patients with arterial hypertension older age is associated with a shift of the autonomic balance towards sympathetic activity, which may translate into an additional increase in cardiovascular risk.

The value of the ablation index in patients undergoing ablation for atrial fibrillation

BACKGROUND

Data on the results of ablation for atrial fibrillation (AF) in Poland are scarce.

AIMS

The aim of the study was to compare the efficacy of ablation index (AI)-guided pulmonary vein isolation (PVI) with that of conventional contact force-based PVI.

METHODS

Consecutive patients undergoing PVI for the first time were included in the study. A nonrandomized retrospective comparison was made between patients ablated with contact force before AI was introduced (non -AI group) and patients ablated with the use of AI (AI group). The AI threshold for the anterior wall / roof of left veins was 500 and 380 elsewhere. The maximal interlesion distance was 6 mm. The follow -up included outpatient visits and 7-day Holter monitoring 6 and 12 months after ablation.

RESULTS

A total of 275 patients were included in the analysis: 133 in the AI group and 142 in the non--AI group. The duration of AF ablation was slightly longer in the AI group, but the fluoroscopy time and the radiofrequency ablation time were shorter in the same group. During the 12-month follow -up period, 25.8% and 40.6% of patients from the AI and non -AI groups, respectively, experienced recurrences (P = 0.02). The log -rank test with an extended follow -up period of up to 18 months confirmed the difference between the AI and non -AI groups, both in the whole group and in the paroxysmal AF and nonparoxysmal AF subgroups (P = 0.001, P = 0.04, and P = 0.006, respectively).

CONCLUSION

The AI -based protocol provides a significant advantage over traditional contact force-based radiofrequency ablation in nonselected patients undergoing PVI.

Serum microRNA in patients undergoing atrial fibrillation ablation

MicroRNAs mediate posttranscriptional gene regulation. The aim of the study was to find a microRNA predictor of successful atrial fibrillation (AF) ablation. A total of 109 patients undergoing first-time AF ablation were included. Nineteen patients were selected to undergo serum microRNA sequencing (study group). The sequencing data were used to select several microRNAs that correlated with 12-month recurrences after AF ablation. Those microRNAs were validated by digital droplet PCR in samples from remaining 90 patients. All patients underwent pulmonary vein isolation (RF ablation, contact force catheter, electroanatomical system). The endpoint of the study was the 12-month AF recurrence rate; the overall recurrence rate was 42.5%. In total, levels of 34 miRNAs were significantly different in sera from patients with AF recurrence compared to patients without AF recurrence. Six microRNAs (miR-183-5p, miR-182-5p, miR-32-5p, miR-107, miR-574-3p, and miR-144-3p) were validated in the whole group. Data from the validation group did not confirm the observations from the study group, as no significant differences were found between miRNAs serum levels in patients with and without recurrences 12 months after AF ablation.

Assessing Efficacy of Canaloplasty Using Continuous 24-Hour Monitoring of Ocular Dimensional Changes

PURPOSE

We investigated whether 24-hour monitoring of corneoscleral limbus area (CSLA) with the Sensimed Triggerfish contact lens sensor (CLS) can be used clinically to assess midterm efficacy of canaloplasty and to assess the relationships of CSLA changes with the heart rhythm.

METHODS

Ten eyes of 10 patients, with POAG, which were qualified either to canaloplasty or canaloplasty and phacoemulsification, were included in this study. Eyes were washed out before the surgery and control visits were done at days 1, 7, and 3, 6, 12 months postoperatively, at which subjects were examined. We performed 24-hour monitoring of CSLA changes and Holter ECG at washout, and at 3- and 12-month postop visits. Raw CLS signals were processed to lead two parameters describing short-term 24-hour variability of CSLA (VAR, â). Heart activity parameters from CLS were compared to those acquired from Holter ECG.

RESULTS

Mean post washout IOP was 20.6 ± 4.7 and decreased to 14.2 ± 3.0 mm Hg 1 year after surgery (P < 0.01). A decreasing trend in VAR and â parameters were noted. Statistically significant differences were found between the washout and 3-month postop visit for VAR and â (P = 0.014 and P = 0.027, respectively) as well as between the washout and 12-month postop result for the parameter â (P = 0.031). No statistically significant differences were found between the 3- and 12-month postop results for both considered parameters.

CONCLUSIONS

Canaloplasty alone or combined with cataract surgery is a successful surgical method of lowering IOP in glaucoma patients. Canaloplasty decreases 24-hour CSLA fluctuation pattern measured with CLS.

Prolonged postocclusive hyperemia response in patients with normal-tension glaucoma

Background

It is believed that endothelial dysfunction may be a link between systemic and ocular dysregulation in glaucoma. The aim of this study was to evaluate peripheral vascular reactive hyperemia in response to occlusion test and to correlate peripheral vascular findings with retrobulbar hemodynamics parameters in patients with normal-tension glaucoma.

Material/Methods

Forty-eight patients with normal-tension glaucoma (mean age 58.1 years, 38 women) and 40 control subjects (mean age 54.1 years, 36 women) were subjected to a brachial arterial occlusion test and color Doppler imaging (LOGIQ 9, GE Medical Systems) of the retrobulbar arteries. Finger hyperemia was assessed by using a 2-channel laser Doppler flowmeter (MBF-3D, Moor Instruments, Ltd.). Time parameters (time to peak flow, half-time of hyperemia, time of recovery) and amplitude parameters (maximum hyperemia response, biological zero) of the post-occlusive reactive hyperemia signal pattern as well as velocities and resistance index of the ophthalmic, central retinal, and short posterior ciliary arteries were evaluated and compared between study groups.

Results

In glaucoma patients, time to peak flow and half-time of hyperemia were significantly longer (21.4 vs. 12.0 s, p=0.02 and 74.1 vs. 44.2 s, p=0.03, respectively) and biological zero was significantly lower (2.4 vs. 3.2, p=0.01) comparing with healthy subjects. In glaucoma patients, peak-systolic and end-diastolic velocities of central retinal artery were significantly lower (12.8 vs.14.1, p=0.03 and 3.9 vs. 4.7, p=0.01, respectively) and resistance index of this artery was significantly higher (0.69 vs. 0.67, p=0.03) compared to controls. In the glaucoma group, maximum hyperemic response was negatively correlated with the resistance index of temporal short posterior ciliary arteries (r=−0.4, p=0.01), whereas in the control group half-time of hyperemia was negatively correlated with end-diastolic velocity of the central retinal artery (r=−0.3, p=0.03).

Conclusions

Arterial occlusion test elicited a prolonged systemic hyperemia response in patients with glaucoma as compared with healthy subjects. Retrobulbar blood flow alterations in glaucoma patients may be related to systemic vascular dysregulation.

Minimizing right ventricular pacing in patients with sinus node disease and prolonged PQ interval: The impact on exercise capacity

BACKGROUND

Several clinical and experimental studies have shown that unnecessary right ventricular pacing in sinus node disease can be detrimental. Inter- and intra-ventricular asynchrony imposed by right ventricular pacing may cause reduction in contractility and relaxation of left ventricle, worsening mitral regurgitation, regional redistribution of myocardial perfusion and oxygen consumption, and asymmetrical hypertrophy of left ventricular wall. In some patients, sinus node disease coexists with impaired atrioventricular conduction. The optimal pacing mode in this population is not determined. Minimizing right ventricular pacing can preserve inter- and intra-ventricular synchrony. On the other hand, longer atrioventricular delay may cause atrioventricular asynchrony. The aim of this study was to prospectively assess the impact of minimizing right ventricular pacing in patients with DDD pacemaker implanted for sinus node disease and prolonged PQ interval on exercise capacity, cardiac function and quality of life.

METHODS

The study enrolled 50 consecutive patients with prolonged PQ interval who were implanted with DDD pacemaker because of sinus node disease. Each patient was treated alternately with 2 pacing modes in random order for 4-month periods: conventional dualchamber pacing and dual-chamber minimal ventricular pacing (prolonged atrioventricular delay). At the end of each phase the following tests were performed: cardiopulmonary exercise testing, echocardiographic evaluation and quality of life assessment (SF36).

RESULTS

There was no significant relationship between pacing mode and cardiopulmonary parameters, echocardiographic parameters and quality of life.

CONCLUSIONS

Sequential atrioventricular pacing may be a reasonable choice for treating patients with sinus node disease and prolonged PQ interval.

Cognitive impairment after appropriate implantable cardioverter-defibrillator therapy for ventricular fibrillation

BACKGROUND

Short periods of cerebral ischaemia during ventricular defibrillation testing may be associated with neuropsychological impairment. However, the impact of out-of-hospital ventricular fibrillation (VF) converted by implantable cardioverter-defibrillator (ICD) shock on cognitive functioning is unknown.

AIM

To assess the impact of out-of-hospital VF converted by ICD shock on cognitive functioning.

METHODS

The study included 52 primary prevention ICD recipients. Patients with a history of stroke or other neurological impairment, previous head injury and individuals unable to see or speak to complete neuropsychological tests were not included.Initially, a Mini-Mental State Examination was performed in all patients and one patient with a result below 24 points was excluded from the study. The cognitive battery consisted of four tests (six measurements): 1) the Digit Span subtest of Wechsler Adult Intelligence Scale-Revised; 2) the Digit Symbol subtest of Wechsler Adult Intelligence Scale-Revised; 3) the Halstead-Reitan Trail-Making Test A and B; and 4) the Ruff Figural Fluency Test.

RESULTS

The mean time from ICD implantation to cognitive assessment was 26 months. During this period, 15 appropriate shocks for VF were observed in seven (14%) patients. The patients with appropriate ICD therapy were significantly worse in two out of the six neuropsychological measurements and had a significantly lower aggregate result. In multivariate linear regression analysis, defibrillation therapy was an independent factor of poor cognitive functioning, along with age and education.

CONCLUSIONS

Short periods of out-of-hospital VF converted by ICD are associated with cognitive impairment in the recipients of primary prevention ICD.

Resolution of exercise oscillatory ventilation with adaptive servoventilation in patients with chronic heart failure and Cheyne-Stokes respiration: preliminary study

BACKGROUND

Exercise oscillatory ventilation (EOV) is a common pattern of breathing in heart failure (HF) patients, and indicates a poor prognosis.

AIM

To investigate the effects of adaptive servoventilation (ASV) on ventilatory response during exercise.

METHODS

We studied 39 HF patients with left ventricular ejection fraction (LVEF) £ 45. Cardiorespiratory polygraphy, cardiopulmonary exercise testing (CPET), echocardiography, and measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration were performed. Twenty patients with Cheyne-Stokes respiration and apnoea-hypopnoea index (AHI) ≥ 15/h were identified. Of these, 11 patients were successfully titrated on ASV and continued therapy. In the third month of ASV treatment, polygraphy, CPET, echocardiography, and measurement of NT-proBNP concentration were performed again.

RESULTS

The EOV was detected at baseline in 12 (31%) HF patients, including eight (67%) who underwent ASV. The EOV was associated with significantly lower LVEF, peak oxygen uptake (VO(2)), and ventilatory anaerobic threshold (VAT), and a significantly higher left ventricular diastolic diameter (LVDD), slope of ventilatory equivalent for carbon dioxide (VE/VCO(2)), AHI, central AHI and NT-proBNP concentration. In seven patients with EOV, reversal of EOV in the third month of ASV therapy was observed; only in one patient did EOV persist (p = 0.0156).

CONCLUSIONS

The EOV can be reversed with ASV therapy. The EOV in association with central sleep apnoea and Cheyne- -Stokes respiration (CSA/CSR) is prevalent in HF patients and correlates with severity of the disease.

Impedance cardiography in the diagnosis of capillary leak syndrome caused by doxorubicin therapy in a patient with myeloma multiplex

Cytotoxicity of drugs can be a cause of cardiorespiratory disorders connected with chemotherapy. Doxorubicin is an antibiotic from the group of anthracyclines effective in antineoplastic therapy of solid and hematopoetic tumors. The most common cause of therapy ceasing is its cardiotoxicity. However, a lung injury connected with its cytotoxic activity to pulmonary endothelium (capillary leak syndrome) can be an equally serious complication. In the case presented, rapid, multi-profile diagnostics with the use of impedance cardiography, a modern noninvasive tool of hemodynamic monitoring, led to the recognition and effective treatment of a rare clinical syndrome.

[Inappropriate therapy of an implantable cardioverter-defibrillator--is it always an undesired event? A case report]

Inappropriate implantable cardioverter defibrillator (ICD) therapy is the commonest adverse event in patients with ICD. We present a case of sinus rhythm restoration after an inappropriate shock in a man with permanent atrial fibrillation and dilated cardiomyopathy. During follow-up, clinical improvement has been observed.

[Autonomic nervous system and primary open angle glaucoma--pathogenetic and clinical correlations]

Primary open angle glaucoma is linked to autonomic nervous system dysfunction. In a review the role of autonomic nervous system as an important determinant of systemic hemodynamic parameters such as heart rate and blood pressure, was presented. Human circadian clock and its impact on autonomic nervous system was emphasized. Finally some autonomic function tests and therapeutical implications were described.

Long-term reproducibility of microvolt T-wave alternans in patients after cardioverter-defibrillator implantation

BACKGROUND

Microvolt T-wave alternans (MTWA) is a promising method for noninvasive assessment of arrhythmic risk. Recent studies have shown good immediate reproducibility of T-wave alternans. Little is known about it during the long term. The aim of the study was to prospectively evaluate the long-term reproducibility of MTWA in a group of patients after ICD implantation.

METHODS

The study group consisted of 22 patients: 21 male and 1 female, aged 63.0 +/- 7.6 years. Nineteen of them had a history of myocardial infarction and 3 had non-ischemic cardiomyopathy. Ejection fraction was 34.7 +/- 10.0. T-wave alternans was measured during treadmill tests and additionally in 6 patients during implantation cardioverter-defibrillator device pacing. We received 30 reports of MTWA available for analysis. The second test was performed after 11.8 +/- 3.3 months (range 7-16) using the same protocol.

RESULTS

Of the 30 tests, 12 were positive, 2 negative and 9 indeterminate in both tests. The results were concordant in 23 tests (76.66%) (Kappa 0.602). Of the initial positive tests, only one became negative in the second test and 4 became indeterminate. Of the initial negative tests, none became positive and none became indeterminate. Of the initial indeterminate tests, one became positive and one negative. At the same time, there were no significant differences between QRS, QTc and ejection fraction between the first and second tests. Only the heart rate in the second test was greater than in the first.

CONCLUSIONS

The results suggest that microvolt T-wave alternans measurement is stable over a long period. It is probably not worth examining the status of MTWA after several months, at least if patients are in the chronic stage of their disease. (Cardiol J 2007; 14: 561-567).

[Positive microvolt T-wave alternans as a marker of ventricular arrhythmia trigering during cardioverter-defibrillator implantation]

Microvolt T-wave alternans (MTWA) is promising method for noninvasive assessment of arrhythmic risk, but its role hasn't established yet. The aim of this study was to establish the MTWA potency to predict the ventricular arrhythmia triggering during implantable cordioverter-defibrillator (ICD) implantation. Material and metods. The study group consisted of 21 patients, aged 63.0+/-8.0 years; EF was 38.0+/-12.8%. Seventeen of them had a history of myocardial infarction and 4 had non-ischemic cardiomyopathy. The reason for ICD implantation were secondary prevention due to nonfatal cardiac arrest caused by VF/VT in nineteen patients and in two patients ICD was implanted because of unexplained syncope and low EF (< or =35%). All patients underwent VT/VF triggering during device implantation caused by electrophysiological study (EPS). If this proved ineffective aggressive protocol of 50 Hz BURST and T SHOCK was applied. After ICD implantation the following tests were performed: ECG with HR, QRS and QTc evaluation, 24-hour ECG Holter monitoring with HRV assessment and MTWA evaluation during treadmill exercise test. Results. In the group with VT/VF induced by less aggressive protocol (EPS), group I (n = 10) MTWA was present in nine patients, in one the result of MTWA was indeterminate. In the group with VT/VF induced by more aggressive protocol, group II (n = 11) MTWA was present in four patients, indeterminate in four and absent in three. There was a significant (p = 0.017) difference between group I and II in the frequency of positive result of MTWA. There were no differences between the two groups according to time domain parameters of HRV such as SDNN, RMSSD and PNN50 and QTc. There was a significant difference between the two groups in time duration of QRS complexes, 118.9+/-14.7 vs. 105.6+/-11.5 accordingly (p < 0.04). Conclusions. MTWA may help identify patients in whom VTNVF is more easily inducible by electrophysiologic study during ICD implantation. It is easier to induce ventricular arrhythmia when QRS complexes are wider, irrelevant to left ventricular dysfunction and autonomic function of the heart.

[N-terminal pro-brain natriuretic peptide (NT-proBNP) and ischemia modified albumin (IMA) in exercise induced ischemia in patients with stable coronary artery disease]

INTRODUCTION

Preliminary data indicate that B type natriuretic peptides' levels may rise in exercise induced myocardial ischemia in patients with stable coronary artery disease. Such findings hint at a potential broader application of these markers reaching beyond its present use in chronic heart failure and acute coronary syndromes. Ischemia modified albumin (IMA) is a novel diagnostic marker in acute coronary syndromes as its value increases in states of myocardial ischemia and necrosis. The role of this marker in the assessment of exercise induced myocardial ischemia in stable coronary artery disease has not been extensively investigated and remains unknown.

AIM

To examine changes in N-terminal pro-brain natriuretic peptide (NT-proBNP) and ischemia modified albumin (IMA) during an ECG stress test in patients with stable coronary artery disease and to assess the potential of these markers to detect exercise induced myocardial ischemia.

PATIENTS AND METHODS

Patients with angiographically confirmed coronary atherosclerosis were included into the study. In all of them prognostic ECG stress test according to Bruce protocol was performed. The test was considered true positive (ischemia present) in case of significant ST-segment depression in the presence of significant coronary stenosis. The test was considered true negative (ischemia absent) when no significant ST depression was noted in the absence of significant coronary stenosis. In all patients echocardiography was performed and blood was drawn for NT-proBNP, IMA, serum albumin and creatinine before and within the first five minutes after exercise.

RESULTS

41 patients with unequivocal stress test result corresponding to coronary angiogram were included in the final analysis (out of 51 examined patients). 21 patients demonstrated ischemia during exercise, 20 did not. NT-proBNP concentration was significantly higher after the stress test than before in the whole group: 127.9 (10.7-994.2) pg/ml and 110 (10.5-990.2) pg/ml respectively; p < 0.0001. NT-proBNP increase was higher in the ischemic than in the non-ischemic group; however, the difference was not statistically significant: deltaNT-proBNP 12.3 (1.0-172.3) pg/ml and 4.2 (1.0-77.1) pg/ml respectively; p = 0.09. This manifested itself in poor sensitivity and specificity of NT-proBNP in detecting exercise induced myocardial ischemia: 62 and 55% respectively (AUC 0.589). In the whole group the increase of NT-proBNP depended on baseline NT-proBNP concentration (r = 0.54; p = 0.0003), the magnitude of ST-segment depression (r = 0.38; p = 0.01), creatinine concentration (r = 0.34; p= 0.03) and history of myocardial infarcion: log deltaNT-proBNP in post-MI patients and in patients without prior MI 1.19 ( +/- 0.54) i 0.61 ( +/- 0.57) respectively; p = 0.004. In multiple regression analysis the only factor independently determining NT-proBNP increase during exercise was the history of myocardial infarction (beta = 0.342; p = 0.01) but not left ventricle ejection fraction. IMA decreased during exercise in all patients significantly--the mean value before and after exercise was 88.20 (7.72) and 78.05 (8.33) U/ml respectively; p = 0.0001. Decrease in IMA correlated only with increase in albumin concentration measured before and after exercise (r = -0.6; p < 0.0001).

CONCLUSIONS

Exercise induced myocardial ischemia has little influence on NT-proBNP increase. The test measuring it has therefore insufficient ability to detect exercise induced ischemia in stable coronary artery disease. In patients with stable coronary artery disease without severe impairment of left ventricular function the history of myocardial infarction is the main factor determining NT-proBNP increase during exercise. Changes in serum albumin concentration during exercise seem to exclude the use of IMA in the assessment of exercise induced myocardial ischemia.

Correlation of B type natriuretic peptides with clinical and echocardiographic parameters in heterogeneous population of patients with symptoms suggestive of heart failure

PURPOSE

NT-proBNP and BNP concentrations in CHF correlate with NYHA class and LVEE Little research has been conducted to compare the clinical performance of these two natriuretic peptides in heterogeneous CHF population. Purpose: to evaluate and compare the clinical performance of NT-proBNP and BNP in heterogeneous group of CHF patients on the basis of these peptides' correlation with NYHA class, LVEF and WMI measured by echocardiography.

MATERIAL AND METHODS

Consecutive patients admitted for suspected of CHE Blood samples were drawn for NT-proBNP, BNP, creatinine and echocardiography was performed.

RESULTS

71 patients were included. CHF was diagnosed in 53. Sensitivity of NT-proBNP and BNP in diagnosing CHF was 83% and 94% respectively (P = 0.079). Levels of both peptides correlated equally well with NYHA class (R = 0.537, p < 0.001; R = 0.473, P < 0.001), LVEF (R = -0.623, p < 0.001; R = -0.601, P < 0.001) and WMI (R = 0.590, P < 0.001; R = 0.527, P = 0.001). Creatinine correlated with both peptides, age correlated with NT-proBNP. No difference between sexes was found in both peptides' concentrations. In multivariate analysis independent determinants of BNP were LVEF, presence of valvular disease and NYHA class. In case of NT-proBNP age and creatinine also displayed independent influence.

CONCLUSIONS

NT-proBNP and BNP show good sensitivity in detecting CHE Levels of both peptides correlate equally well with clinical and echocardiographic parameters of CHF, which makes them equally adequate in biochemical staging of CHF's severity regardless of its underlying cause. Levels of natriutretic peptides reflect contractile dysfunction, valvular disease and clinical condition. Age and creatinine concentration but not patients' sex should additionally be considered when measuring NT-proBNP.