Robert Holaj

Dr. Robert Holaj

General University Hospital in Prague, Czech Republic
orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2017 in Hypertension
Verified
Journal Article
Closed access
PGPankaj Gupta
Pankaj Gupta
PPPrashanth Patel
Prashanth Patel
BŠBranislav Štrauch
Branislav Štrauch
FLFlorence Y. Lai
Florence Y. Lai
AAArtur Akbarov
Artur Akbarov
MTMaciej Tomaszewski
Maciej Tomaszewski
Nonadherence to antihypertensive treatment is a critical contributor to suboptimal blood pressure control. There are limited and heterogeneous data on the risk factors for nonadherence because few studies used objective-direct diagnostic methods. We used high-performance liquid chromatography-tandem mass spectrometry of urine and serum to detect nonadherence and explored its association with the main demographic- and therapy-related factors in 1348 patients with hypertension from 2 European countries. The rates of nonadherence to antihypertensive treatment were 41.6% and 31.5% in the UK and Czech populations, respectively. Nonadherence was inversely related to age and male sex. Each increase in the number of antihypertensive medications led to 85% and 77% increase in nonadherence (P<0.001) in the UK and Czech populations, respectively. The odds of nonadherence to diuretics were the highest among 5 classes of antihypertensive medications (P≤0.005 in both populations). The predictive model for nonadherence, including age, sex, diuretics, and the number of prescribed antihypertensives, showed area under the curves of 0.758 and 0.710 in the UK and Czech populations, respectively. The area under the curves for the UK model tested on the Czech data and for the Czech model tested on UK data were calculated at 0.708 and 0.756, respectively. We demonstrate that the number and class of prescribed antihypertensives are modifiable risk factors for biochemically confirmed nonadherence to blood pressure–lowering therapy. Further development of discriminatory models incorporating these parameters might prove clinically useful in assessment of nonadherence in countries where biochemical analysis is unavailable.

1 February 2015 in Hypertension
Verified
Journal Article
Open access
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JRJán Rosa
Ján Rosa
PWPetr Widimský
Petr Widimský
PTPetr Toušek
Petr Toušek
OPOndrej Petrak
Ondrej Petrak
KCkarol curila
karol curila
JWJiri Widimsky
Jiri Widimsky
This prospective, randomized, open-label multicenter trial evaluated the efficacy of catheter-based renal denervation (Symplicity, Medtronic) versus intensified pharmacological treatment including spironolactone (if tolerated) in patients with true-resistant hypertension. This was confirmed by 24-hour ambulatory blood pressure monitoring after excluding secondary hypertension and confirmation of adherence to therapy by measurement of plasma antihypertensive drug levels before enrollment. One-hundred six patients were randomized to renal denervation (n=52), or intensified pharmacological treatment (n=54) with baseline systolic blood pressure of 159±17 and 155±17 mm Hg and average number of drugs 5.1 and 5.4, respectively. A significant reduction in 24-hour average systolic blood pressure after 6 months (−8.6 [95% cofidence interval: −11.8, −5.3] mm Hg; P <0.001 in renal denervation versus −8.1 [95% cofidence interval: −12.7, −3.4] mm Hg; P =0.001 in pharmacological group) was observed, which was comparable in both groups. Similarly, a significant reduction in systolic office blood pressure (−12.4 [95% cofidence interval: −17.0, −7.8] mm Hg; P <0.001 in renal denervation versus −14.3 [95% cofidence interval: −19.7, −8.9] mm Hg; P <0.001 in pharmacological group) was present. Between-group differences in change were not significant. The average number of antihypertensive drugs used after 6 months was significantly higher in the pharmacological group (+0.3 drugs; P <0.001). A significant increase in serum creatinine and a parallel decrease of creatinine clearance were observed in the pharmacological group; between-group difference were borderline significant. The 6-month results of this study confirmed the safety of renal denervation. In conclusion, renal denervation achieved reduction of blood pressure comparable with intensified pharmacotherapy.

19 April 2012 in Hormone and Metabolic Research
Verified
Journal Article
Closed access
PDF file
TZT. Zelinka
T. Zelinka
OPOndrej Petrak
Ondrej Petrak
HTH. Turková
H. Turková
RHRobert Holaj
Robert Holaj
BŠB. Štrauch
B. Štrauch
JWJiri Widimsky
Jiri Widimsky
Excess of catecholamines in pheochromocytoma is usually accompanied with classical symptoms and signs. In some cases, severe cardiovascular complications (e. g., heart failure, myocardial infarction) may occur. We performed a retrospective analysis focused on the incidence of cardiovascular complications (classified as follows: arrhythmias, myocardial involvement or ischemia and atherosclerosis, cerebrovascular impairment) before the establishment of diagnosis of pheochromocytoma among 145 subjects treated in our hospital. Cardiovascular complications occurred in 28 subjects, but these subjects did not differ significantly from subjects without complications in age, gender, body mass index, paroxysmal symptoms, symptom duration, tumor dimension, catecholamine secretory phenotype, and incidence of hypertension or diabetes mellitus. Arrhythmias occurred in 15 subjects (2 arrhythmia types in 2 subjects): atrial fibrillation in 9 subjects, supraventricular tachycardia in 3 cases, and ventricular tachycardia in 2 patients. Significant bradycardia was noted in 3 cases. Five subjects presented with heart failure with decreased systolic function (takotsubo-like cardiomyopathy found in 2 cases). One subject suffered from hypertrophic obstructive cardiomyopathy. Seven subjects presented with non-ST-segment elevation myocardial infarction, 2 patients with ST-segment myocardial infarction, and 1 subject underwent coronary artery bypass grafting. Two subjects suffered from significant peripheral atherosclerosis. Among cerebrovascular complications, transient ischemic attack was found in 3 cases, 2 subjects suffered from stroke, and subarachnoidal bleeding occurred in 1 patient. One subject suffered from diffuse neurological impairment due to multiple ischemic white matter lesions. These data show relatively high incidence of cardiovascular complications (19.3%) in subjects with pheochromocytoma. Early diagnosis is mandatory to prevent severe complications in pheochromocytoma.

1 December 2013 in Journal Of Hypertension
Verified
Journal Article
Closed access
BŠBranislav Štrauch
Branislav Štrauch
OPOndrej Petrak
Ondrej Petrak
TZTomáš Zelinka
Tomáš Zelinka
JRJán Rosa
Ján Rosa
ZŠZuzana Šomlóová
Zuzana Šomlóová
JWJiri Widimsky
Jiri Widimsky
The aim of our study was to assess the prevalence of pseudo-resistance caused by noncompliance with treatment among patients with severe resistant hypertension and to analyze the contributing factors. Three hundred and thirty-nine patients (195 men) with resistant essential hypertension were studied. The first group consisted of 176 patients admitted for hospitalization for exclusion of a secondary cause to our hypertension centre (103 men); the second one consisted of 163 out-patients (92 men) investigated for the first time in an out-patient hypertension clinic. Unplanned blood sampling for assessment of serum antihypertensive drug concentrations by means of liquid chromatography-mass spectrometry was performed in all patients. Our main finding is a surprisingly low compliance with drug treatment in out-patients with resistant hypertension (23% partially noncompliant and 24% totally noncompliant - in total, 47% prevalence of noncompliance). Eighty-one percent of hospitalized patients were positive, in 10% the results were partially positive and in 9% of the patients, the drugs were all negative. The compliance among hospitalized patients was probably better due to lower numbers of prescribed drugs and expected thorough investigation. More frequently, noncompliance was found in nonworking (potential purpose-built behaviour), younger and less well educated patients. The most frequent noncompliance was to doxazosine, spironolactone and hydrochlorothiazide. We have observed a surprisingly low compliance with treatment among out-patients with severe hypertension. We conclude that the evaluation of antihypertensive drugs concentrations is a useful and precise method for assessment of noncompliance in patients with resistant hypertension. This evaluation is useful before starting the diagnostic work-up of secondary forms of hypertension and before assignment patients into protocols with new therapy modalities such as renal denervation.

1 September 2006 in American Journal of Hypertension
Verified
Journal Article
Closed access
BSB Strauch
B Strauch
OPOndrej Petrak
Ondrej Petrak
DWD Wichterle
D Wichterle
TZT Zelinka
T Zelinka
RHRobert Holaj
Robert Holaj
JWJ Widimskyjr
J Widimskyjr
Aldosterone has been shown to substantially contribute to the accumulation of collagen fibers and growth factors in the arterial wall, which can increase wall stiffness. This study aimed at comparing arterial stiffness between patients with primary aldosteronism (PA), essential hypertension (EH), and normotensive controls using carotid-femoral pulse wave velocity (PWV) and central augmentation index (AI). Thirty-six patients with confirmed PA, 28 patients with EH, and 20 normotensive subjects were investigated by Sphygmocor applanation tonometer. The office blood pressure (BP) at the time of the measurement (PA 167+/-34/92+/-12 mm Hg; EH 166+/-19/91+/-10 mm Hg), age, body mass index (BMI), cholesterol, triglyceride, blood glucose levels were comparable between PA and EH groups. The patients with PA had significantly higher PWV than the EH patients and control subjects (9.8+/-2.6 m/sec v 7.5+/-1.0 m/sec v 5.9+/-0.7 m/sec, respectively; all mutual differences P<.001). The difference in PWV between PA and EH remained statistically significant also after the adjustment for all clinical variables including 24-h BP using multivariate analysis (P=.001). Arterial wall stiffness is independently increased in PA compared to EH. This could be caused by the deleterious effects of aldosterone excess (potentially modulated by hypernatremia) on the fibrosis and remodeling of the arterial wall.

1 May 2006 in Cerebrovascular Diseases
Verified
Journal Article
Closed access
Libor VitekLibor Vitek
Libor Vitek
LNLadislav Novotný
Ladislav Novotný
MŠMichal Šperl
Michal Šperl
RHRobert Holaj
Robert Holaj
JSJiří Spáčil
Jiří Spáčil
Background: Serum bilirubin is negatively associated with the development of coronary heart disease. In the present study, we have focused on the analysis of intima-media thickness (IMT) of the common carotid artery in hyper- and normobilirubinemic subjects. Methods: The study was performed on 111 men without manifested atherosclerosis. In all subjects, complete biochemical tests were determined along with the examination of IMT by carotid ultrasound. Results: The mean IMT in hyperbilirubinemic subjects as compared with controls was substantially lower (p = 0.017), and hyperbilirubinemic men also had very low age-adjusted prevalence odds ratios for having IMT above the 50th percentiles of controls, even after adjustment for selected vascular risk factors (p = 0.034). Conclusions: In the present study, we demonstrate the inverse relationship between serum bilirubin and IMT in healthy men.