How safe is surgery in obese lung cancer patients?

e17555 Background: Obesity is a risk factor for increased peri-operative morbidity and mortality in surgery. There have been limited studies to correlate morbidity of lung cancer resection with obesity. Methods: We performed a retrospective study of patients who underwent surgical resection for lung cancer at the Medical College of Wisconsin from 2006 to 2010. Data on patient demographics, weight, pathology findings and hospital course were abstracted after appropriate IRB approval. Peri-operative morbidity was defined as atrial fibrillation, heart failure, respiratory failure, pulmonary embolism or any medical complications arising within 30 days after surgery. Fisher’s exact test was used to test the association between BMI and perioperative morbidities. Results: Between 2006 and 2010, 320 lung resections were performed for lung cancer. Median age was 67 (25-88) years and 185 (57.8%) were females. The body mass index (BMI) distribution was 121 (37.8%) in BMI<25 and 199(62.18%) in BMI≥25. In patients with BMI < 25, surgical procedures consisted 76 (23.75%) lobectomy, 38 (11.8%) wedge resection and 7 (2.18%) pneumonectomy. In patients with BMI ≥ 25, surgical procedures consisted: 131 (40.93%) lobectomy, 61 (19.06%) wedge resection and 7 (2.18%) pneumonectomy. Tumor histology was: adenocarcinoma 138 (42.9%), squamous cell cancer 107 (33.3%), bronchoalveolar 25 (7.7%), large cell 19 (5.9%) and mixed 31 (9.68%). The 30-day mortality rate was 1.8 % (6 patients), out of which only 2 had BMI ≥ 25. Peri-operative morbidity occurred in 28 (23.14%) of normal BMI patients and 47 (23.6%) of BMI ≥ 25 patients (p=0.54). Specific morbidities encountered by patients with normal vs. BMI ≥ 25 were: atrial fibrillation 11(9.09%) vs. 24(12.06%) (p=0.46), pulmonary embolism 1(0.83%) vs. 3(1.51%) (p=1.0), congestive heart failure 2(1.65%) vs. 2(1.01%) (p=0.63), respiratory failure 12(9.92%) vs. 17(8.54%) (p=0.69) and ARDS 2(1.65%) vs. 1(0.50%) (p=0.55).Median hospital stay was 5 days in lower BMI group and 4 days in BMI ≥25 groups (p=0.52). Conclusions: Potential curative surgical resections can be offered to even significantly overweight patients as there is no significant difference in the peri-operative morbidities and length of stay as compared to normal BMI patients.

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Caesarean Section in Eclampsia and its Outcome in Bangladesh

KYAMC Journal ◽

10.3329/kyamcj.v6i1.32787 ◽

2017 ◽

Vol 6 (1) ◽

pp. 583-586

Author(s):

MA Mazid ◽

Shahida Akter

Keyword(s):

Heart Failure ◽

Pulmonary Embolism ◽

Caesarean Section ◽

Conservative Management ◽

Causes Of Death ◽

Post Partum ◽

Economic Status ◽

Treatment Options ◽

Age Difference ◽

Significant Difference

This prospective study was carried out on a total number of 58 eclamptic subjects during the period of July 2010 to June 2012 where 38 were undergone caesarean section (LUCS - Lower Uterine Caesarean Section) and 20 received conservative management. Mean (±SD) Age of the subjects who undergone Caesarean Section and conservative management (NVD) were 23.67±8.63 and 23.45±9.31 years respectively. Significant mean age difference was also present between these two groups. In 38 subjects of LUCS 34 subjects were recovered and rest 4 cases were died. Possible causes of death were due to heart failure and post partum pulmonary embolism. Among these 20 subjects who were treated conservatively 14 were recovered and 6 subjects were died. Causes of death in these groups were pulmonary embolism, Septic pneumonia, and HELLP syndrome. Significant difference was found between these two treatment options. It was observed that socio-demographic, economic status and BMI had significant effects on management outcome.KYAMC Journal Vol. 6, No.-1, Jul 2015, Page 583-586

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Comparison between Vinorelbine–Carboplatin and Vinorelbine–Cisplatin in Stage III–IV EGFR Mutations-Negative NSCLC

Asian Journal of Oncology ◽

10.1055/s-0041-1730255 ◽

2021 ◽

Author(s):

Laksmi Wulandari ◽

Gatot Soegiarto ◽

Anna Febriani ◽

Farah Fatmawati ◽

Wirya Sastra Amran

Keyword(s):

Lung Cancer ◽

Body Weight ◽

Evaluation Criteria ◽

Growth Factor Receptor ◽

The Body ◽

Stage Iii ◽

Egfr Mutations ◽

Group I ◽

Significant Difference ◽

Group Ii

Abstract Introduction There are a substantial number of lung cancer patients with negative mutations in Indonesia. This type of cancer is deemed to be the major contributor of lung cancer patient’s death. However, reseaerch related to therapy using vinorelbine combined with platinum-based compounds is still scarce in Indonesia. The aim of this study was to compare the efficacy and tolerability between vinorelbine and carboplatin with vinorelbin and cisplatin in stage III-IV epidermal growth factor receptor (EGFR) mutations-negative non-small cell lung cancer (NSCLC). Methods The participants were divided into two groups—group I(vinorelbine–carboplatin) and group II (vinorelbine–cisplatin). The participants were assessed based on several measurement criteria. Not only Eq-5D was performed, but the body weight and response evaluation criteria for solid tumors (RECIST) were also examined. The participants received chemotherapy for four cycles (1 cycle = 21 days). Results The quality of life was considered stable in 60% of group I and 60% of group II (p=0.255). In both groups, 46.67% of participants had an increased body weight, while the other 20.00% was stable (p = 1.000). In terms of RECIST evaluation after the second cycle, 80.00% of group I and 86.67% of group II were considered to have a stable disease, with 20% of group I and none of group II had partial response (p = 0.027). However, after the fourth cycle, there were no significant difference between the groups (p = 0.734). Conclusion In EGFR mutation-negative NSCLC patients, the combination of vinorelbine and carboplatin showed comparable outcomes to vinorelbine and cisplatin chemotherapy with no significant differences.

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P1087Prevalence and significance of mitral regurgitation in atrial fibrillation coexisting with HFpEF and HFmEF

EP Europace ◽

10.1093/europace/euaa162.292 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

I Lupasteanu ◽

A Vijan ◽

C Delcea ◽

C Stanescu ◽

S Bari ◽

...

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Ejection Fraction ◽

Prognostic Significance ◽

Surrogate Marker ◽

Distinct Type ◽

Mitral Annulus ◽

Mitral Valve Regurgitation ◽

Vena Contracta ◽

Significant Difference

Abstract Background Recent data has acknowledged atrial induced functional mitral valve regurgitation (MR) in the setting of atrial fibrillation (AF) and/or heart failure with preserved ejection fraction (HFpEF) as a distinct type of secondary MR, holding prognostic significance. However, evidence on its prevalence is still scarce, especially in the phenotype of mid-range ejection fraction heart failure (HFmEF). Purpose The aim of this study is to evaluate the occurrence of left atrial (LA) enlargement and MR in AF patients with or without heart failure with preserved or mid-range ejection fraction. Methods This retrospective study included 750 consecutive patients with AF admitted to a tertiary hospital from January 2018 to June 2019. We excluded patients with primary valvular disease and HF with reduced EF. MR presence and severity were assessed by evaluating the valve morphology, colour flow imaging and, when feasible, vena contracta and PISA methods. We measured LA anteroposterior diameter and used LA dilatation as a surrogate marker for mitral annulus dilatation. Results We evaluated 584 AF patients: mean age 72.22 ± 10.10 years; 58,73% females; 79.75% had HF: 73.13% of them had HFpEF and 26.87% had HFmEF. Compared to those without HF, patients with HF had a relative risk (RR) of associating LA enlargement of 5.37 (95%CI = 3.05-9.48, p < 0.001) and a RR of associating MR of 1.47 (95%CI 1.08-2.00, p = 0.01). Mean LA diameter was higher in the HF group, compared to non-HF (47.06 ± 7.26 mm vs 40.91 ± 7.10 mm, p < 0.001). MR severity was more likely associated with HF (RR = 1.68, 95%CI = 1.46-1.94, p < 0.001). When comparing results between the two HF subgroups, patients with HFmEF had a higher mean LA diameter than those with HFpEF (48.52 ± 5.68 mm vs 46.36 ± 7.57 mm, p = 0.011), without associating a significant difference in the MR prevalence (72.97% vs 73.98%, p = 0.94). The presence of a dilated LA was directly correlated with MR in the HF group (RR = 1.94, 95%CI = 1.18-3.20, p = 0.023), but not in those without HF (RR = 1.04, 95%CI = 0.57-1.90, p = 0.89). In HF patients, permanent AF associated the highest prevalence of LA dilatation (96.67%) and MR (81.73%) in contrast to paroxysmal AF (81.10%, p < 0.01, respectively 63.43%, p = 0.0002). Conclusions LA dilatation, the presence and severity of MR correlated with AF and HF, especially in permanent AF patients. In patients without HF, LA dilatation did not correlate with the presence of MR. MR prevalence was similar in patients with HFmEF and HFpEF, irrespective of a higher degree of LA dilatation in HFmEF. Our results suggest that the pathophysiological mechanisms involved in LA enlargement and MR are different for different phenotypes of AF in patients with or without HF.

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The Effect of Echocardiography Based on Lipid Nano Contrast Agent on Cardiology Patients with Heart Failure and Atrial Fibrillation

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.18687 ◽

2021 ◽

Vol 21 (2) ◽

pp. 852-858

Author(s):

Lizhong Wang ◽

Jianing Xi ◽

Qian Cao ◽

Yaowen Jia ◽

Zhenying Zhang ◽

...

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Contrast Agent ◽

Stress Echocardiography ◽

Clinical Symptoms ◽

Diastolic Heart Failure ◽

Significant Difference ◽

Patients With Heart Failure ◽

Before And After ◽

Conventional Echocardiography

This paper discusses the effect and evaluation of echocardiography based on lipid nano contrast agent on patients with heart failure and atrial fibrillation in cardiology department, providing reference for clinical diagnosis and treatment. Fifty two patients with diastolic heart failure diagnosed by echocardiography were selected for routine echocardiographic examination after optimizing the drug treatment scheme, and then the patients underwent treadmill exercise test and stress echocardiography evaluation. The results of conventional echocardiography and stress echocardiography after treatment were compared with those before treatment, and the clinical parameters and biochemical indexes before and after treatment were compared. Results after treatment, the clinical symptoms of the patients improved, the level of NT proBNP in the N-terminal forebrain decreased significantly, and the exercise tolerance increased significantly. Compared with the conventional echocardiography before and after treatment, the left ratio and e′ value of stress echocardiography after treatment increased significantly, while E/e′ decreased significantly. There was no significant difference in the indexes of general echocardiography before and after treatment. After treatment, positively correlated with the ratio of peak a to peak E. The results show that the sensitivity of stress echocardiography to evaluate ischemic diastolic heart failure has been improved, and some indexes have clinical significance. Compared with conventional echocardiography, it can effectively evaluate the therapeutic effect of drugs.

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Lung function tests, exercise capacity and postoperative outcomes of patients with pulmonary resections

Pneumologia ◽

10.2478/pneum-2021-0005 ◽

2021 ◽

Vol 69 (3) ◽

pp. 159-165

Author(s):

Irina Pele ◽

Ciprian Bolca ◽

Ștefan Dumitrache-Rujinski ◽

Florin Mihălțan

Keyword(s):

Lung Cancer ◽

Respiratory Failure ◽

Lung Function ◽

Exercise Test ◽

Postoperative Outcomes ◽

Air Leak ◽

Respiratory Complications ◽

Significant Difference ◽

Prolonged Air Leak ◽

Postoperative Atelectasis

Abstract Aim: Postoperative complications, especially pulmonary complications, are described after lung resections, with different risk factors involved. We evaluate the relationship between lung function, exercise test parameters and the occurrence of postoperative outcomes in patients with pulmonary resections. Methods: A 5 years prospective observational study on patients with lung resection (lobectomy, bilobectomy and pneumonectomy) for lung cancer and other pulmonary pathologies has been performed. All the patients were preoperatively evaluated using spirometry, plethysmography, diffusing capacity test and cardio-pulmonary exercise test (CPET). Data were analysed regarding the linkage between cardiopulmonary fitness and postoperative outcomes (respiratory complications and 90-day mortality). Results: Of 155 consecutive patients (109 male, mean age 61.2 ± 9.8 years), 130 (83.9%) underwent pulmonary resection for lung cancer. Nearly 24% of patients developed postoperative respiratory complications (mainly atelectasis, prolonged air leak and respiratory failure). The 90-day mortality was 5.2%. A reduced absolute value of forced expiratory volume in 1 s (FEV1) was found to be associated with postoperative atelectasis [odds ratio (OR) 0.33; 95% confidence interval (CI) 0.11–0.99], but with low accuracy. The most related variable and a predictor to prolonged air leak was FEV1/vital capacity (VC) ratio (OR 0.90; 95% CI 0.83–0.99). Patients who developed respiratory failure had lower values of static volumes and breathing reserve (BR%) compared to those without respiratory failure, but with no significant difference (P > 0.050). No relationship to mortality was noted. Conclusion: In our study group, lower values of FEV1 were related to postoperative atelectasis and obstructive dysfunction with persistent air leak, with no significant association with mortality.

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Progrostic impact of a pre-existing heart failure with preserved ejection fraction in patients with acute pulmonary embolism or paroxysmal atrial fibrillation

European Journal of Preventive Cardiology ◽

10.1093/eurjpc/zwab061.017 ◽

2021 ◽

Vol 28 (Supplement_1) ◽

Author(s):

N Tufano

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Pulmonary Embolism ◽

Ejection Fraction ◽

Clinical Outcomes ◽

Acute Pulmonary Embolism ◽

Older Age ◽

Lower Percentage ◽

Preserved Ejection Fraction ◽

Acute Pe

Abstract Funding Acknowledgements Type of funding sources: None. OnBehalf none Introduction heart failure with preserved ejection fraction (HFpEF) is a growing public health problem. Its prevalence among heart failure patients increases over time, accounting for at least 50 % of all hospital admissions for HF. Nevertheless, no single guideline exists for diagnosis or treatment for HFpEF, and older age or comorbidities are additional factors that confuse etiology and complicate prognosis. Moreover, there are few data regarding the consequences of HFpEF on other recurrent pathologies. Aims to assess the prognostic impact of a pre-existing HFpEF on patients ospidalized for intercurrent episodes of atrial fibrillation (AF) or acute pulmonary embolism (PE) Methods We performed a retrospective evaluation of 194 patients, consecutively hospitalized in our unit of Cardiology with a diagnosis of paroxysmal AF or acute PE, from April 2017 to October 2020. We recruited exclusively patients with normal cardiac function and HFpEF patients. Heart failure with reduced FEVS patients were excluded from the study. We have described for each patient the demographic and clinical characteristics, comorbidities, instrumental test results and clinical outcomes. In order to assess, for each group, the relationship between patient characteristics and clinical outcomes, the Chi-square test or alternatively the Pearson-Spearman correlation coefficients were calculated. Results the 194 patients studied had an average age of 73,7 years (min. 27, max 94). 59 AF patients had pre-existing HFpEF, whereas AF patients without HF were 67. Patients with pre-existing HFpEF and newly-onset AF had a more advanced age (76,7 y vs 72,9 y), and greater comorbidity (meanly 4 vs 3) rather than AF patients without HFpEF. Moreover, percentage of converting arrhythmia were significantly higher in AF patients without HFpEF. . Patients with acute PE and pre-existing HFpEF were 38, whereas PE patients without HF were 30. Acute PE patients with pre-existing HFpEF had older age, a prevalence for femal sex, more comorbidities, an average longer hospitalizations, but no significantly different rates of severe complications (ictus, hemorrhagies, needs for ventilation, pulmonary infarction or deaths) rather than PE patients without HFpEF. Conclusions the patients with AF or PE and concomitant HFpEF that were hospitalized from April 2017 to October 2020, showed an average longer hospitalization, a lower percentage of converting arrhythmia, probably due to the older age and the greater comorbidity.

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The cholesterol paradox in atrial fibrillation: results from the LIPIDOGRAM 2015 study

European Heart Journal ◽

10.1093/ehjci/ehaa946.0451 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

S Harrison ◽

G.Y.H Lip ◽

D.A Lane ◽

M Mastej ◽

S Kasperczyk ◽

...

Keyword(s):

Atrial Fibrillation ◽

Reference Group ◽

Large Population ◽

Density Lipoprotein ◽

The Body ◽

Lipoprotein Cholesterol ◽

Inverse Association ◽

Confounding Factors ◽

Lipid Levels ◽

Significant Difference

Abstract Background High blood lipid levels are known risk factors for atherosclerotic cardiovascular events, but associations between lipid levels and atrial fibrillation (AF) are unclear. Some previous studies have suggested an inverse association between lipid levels and AF referred to as the “cholesterol paradox”. Purpose To examine the prevalence of AF by differing lipid levels in a large population-based study of almost 14,000 adults in Poland. Methods The LIPIDOGRAM 2015 study is a cross-sectional study of adults aged 18 years and older recruited in Poland in 2015/2016 by 438 family physicians. Poisson regression models with robust variance were used to estimate prevalence ratios (PRs) for AF with 95% confidence intervals (CIs) for participants with differing lipid profiles. Lipid measures including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), total cholesterol (TC) and LDL/HDL ratios were grouped into quartiles with the lowest quartile as the reference group. Models were adjusted for potential confounding factors including age, sex, waist-to-hip ratio, smoking, alcohol intake, regular physical activity, hypertension, antihypertensive medication use and treatment of dyslipidaemia. Results 13,724 participants were recruited to the study, the median (interquartile range: IQR) age was 58.0 (47.7–65.8) years and 5.2% (n=708) had a diagnosis of AF, with a median (IQR) 3 (1–8) years since diagnosis. After adjusting for potential confounding factors, a statistically significant lower prevalence of AF was estimated for participants in the highest quartile for LDL-C (PR (95% CI): 0.60 (0.48, 0.75) p<0.001), HDL-C (0.58 (0.46, 0.74), p<0.001), TC (0.61 (0.49, 0.75), p<0.001) and LDL/HDL ratio (0.75 (0.61, 0.94), p=0.010). No statistically significant difference in prevalence of AF was observed for participants in the highest quartile for TG levels compared to the lowest quartile for TG levels. Conclusions The prevalence of AF was lower for people with higher levels of LDL-C, HDL-C, TC and higher LDL/HDL ratios; some of the difference in prevalence was explained by controlling for confounding factors, but in multivariable models the association remained statistically significant. This research adds to the body of evidence which suggests an inverse relationship between cholesterol levels and AF-the “cholesterol paradox” for AF. Funding Acknowledgement Type of funding source: None

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P6355The behavior of atrial fibrillation in patients with heart failure hospitalization

European Heart Journal ◽

10.1093/eurheartj/ehz746.0951 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

M Fukunaga ◽

K Hirose ◽

A Isotani ◽

T Morinaga ◽

K Ando

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Cardiovascular Disease ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Significant Difference ◽

The Impact

Abstract Background Relationship between atrial fibrillation (AF) and heart failure (HF) is often compared with proverbial question of which came first, the chicken or the egg. Some patients showing AF at the HF admission result in restoration of sinus rhythm (SR) at discharge. It is not well elucidated that the restoration into SR during hospitalization can render the preventive effect for rehospitalization. Purpose To investigate the impact of restoration into SR during hospitalization for readmission rate of the HF patients showing AF. Methods We enrolled consecutive 640 HF patients hospitalized from January 2015 to December 2015. Patients data were retrospectively investigated from medical record. Patients showing atrial fibrillation on admission but unrecognized ever were defined as “incident AF”; patients with AF diagnosed before admission were defined as “prevalent AF”. Primary endpoint was a composite of death from cardiovascular disease or hospitalization for worsening heart failure. Secondary endpoints were death from cardiovascular disease, unplanned hospitalization related to heart failure, and any hospitalization. Results During mean follow up of 19 months, 139 patients (22%) were categorized as incident AF and 145 patients (23%) were categorized as prevalent AF. Among 239 patients showing AF on admission, 44 patients were discharged in SR (39 patients in incident AF and 5 patients in prevalent AF). Among incident AF patients, the primary composite end point occurred in significantly fewer in those who discharged in SR (19% vs. 42% at 1-year; 23% vs. 53% at 2-year follow-up, p=0.005). To compare the risk factors related to readmission due to HF with the cox proportional-hazards model, AF only during hospitalization [Hazard Ratio (HR)=0.37, p<0.01] and prevalent AF (HR=1.67, p=0.04) was significantly associated. There was no significant difference depending on LVEF. Conclusion Newly diagnosed AF with restoration to SR during hospitalization was a good marker to forecast future prognosis.

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Abstract 16085: Digoxin is Associated With Increased Mortality in Patients With Atrial Fibrillation Without Concomitant Heart Failure

Circulation ◽

10.1161/circ.142.suppl_3.16085 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Maciej Tysarowski ◽

Nigri Rafael ◽

Hyoeun Kim ◽

Emad Aziz

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Left Ventricular Ejection Fraction ◽

Ejection Fraction ◽

Left Ventricular ◽

Ventricular Ejection ◽

Left Ventricular Ejection ◽

Ventricular Ejection Fraction ◽

Significant Difference ◽

All Cause Mortality

Introduction: There is conflicting data on the effect of digoxin on all-cause mortality in patients with atrial fibrillation (AF), especially in patients with heart failure (HF). Hypothesis: We hypothesized that in patients with AF, mortality rates associated with digoxin treatment are different among patients with HF and without HF. Methods: We conducted a cohort study of hospitalized patients with AF assessing the effects of digoxin on all-cause mortality. We divided patients into two groups: with and without HF. We performed Cox regression analysis to assess hazard ratios (HR) for all-cause mortality depending on digoxin treatment and used propensity score matching to adjust for differences in background characteristics between treatment groups. Results: Among 2179 consecutive patients, the median age was 73 ± 14 (table), 53% patient were male, 49% had HF, 19% were discharged on digoxin. Median left ventricular ejection fraction in the cohort was 60 (IQR 40-65). Among patients with HF, 35% had preserved, 18% had mid-range and 48% had reduced left ventricular ejection fraction. The mean follow-up time was 3 ± 2.1 years. After adjustment, in patients with HF, there was no statistically significant difference in mortality between the digoxin subgroups ( A , HR=1.01 [95% CI 0.76 to 1.35], p=0.92). In contrast, after adjustment, in patients without HF there was a statistically significant increased mortality in the digoxin subgroup ( B , HR=2.23, [95% CI 1.42 to 3.51], p<0.001). Conclusions: Digoxin use was associated with increased mortality in patients with AF and without concomitant HF. This suggests that clinicians should be careful in prescribing digoxin for rate control in AF, especially in patients without concomitant HF.

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Robust correlation dimension estimator for heart rate variability

Klinical Informatics and Telemedicine ◽

10.31071/kit2020.16.06 ◽

2020 ◽

Vol 15 (16) ◽

pp. 62-68

Author(s):

A.V. Martynenko ◽

Keyword(s):

Heart Failure ◽

Atrial Fibrillation ◽

Congestive Heart Failure ◽

Sinus Rhythm ◽

Correlation Dimension ◽

Normal Sinus Rhythm ◽

Robust Estimator ◽

Normal Sinus ◽

Significant Difference ◽

Limited Length

Introduction. Non-linear methods of analysis have found widespread use in the Heart Rate Variability (HRV) technology, when the long-term HRV records are available. Using one of the effective nonlinear methods of analysis of HRV correlation dimension D2 for the standard 5-min HRV records is suppressed by unsatisfactory accuracy of available methods in case of short records (usually, doctors have about 500 RRs during standard 5-min HRV record), as well as complexity and ambiguity of choosing additional parameters for known methods of calculating D2. The purpose of the work. Building a robust estimator for calculating correlation dimension D2 with high accuracy for limited se-ries of RR-intervals observed in a standard 5-minute HRV record, i. e. with N  500. As well as demonstrating the capabilities of the D2 formula on a well known attractors (Lorenz, Duffing, Hennon and etc.) and in applications for Normal Sinus Rhythm (NSR), Congestive Heart Failure (CHF) and Atrial Fibrillation (AF). Materials and Methods. We used MIT-BIH long-term HRV records for normal sinus rhythm, congestive heart failure and atrial fibrillation. In order to analyze the accuracy of new robust estimator for D2, we used the known theoretical values for some famous attractors (Lorenz, Duffing, Hennon and etc.) and the most popular Grassberger-Procaccia (G-P) algorithm for D2. The results of the study. We have shown the effectiveness of the developed D2 formula for time series of limited length (N = 500–1000) by some famous attractors (Lorenz, Duffing, Hennon and etc.) and with the most popular Grassberger-Procaccia (G-P) algorithm for D2. It was demonstrated statistically significant difference of D2 for normal sinus rhythm and congestive heart failure by standard 5 min HRV segments from MIT-BIH database. The promised technology for early prediction of atrial fibrillation episodes by current D2 algorithm was shown for standard 5 min HRV segments from MIT-BIH Atrial Fibrillation database. Conclusion. Robust correlation dimension D2 estimator suggested in the article allows for time series of limited length (N ≈ 500) to calculate D2 value that differs at mean from a precise one by 5 ± 4%, as demonstrated for various well known attractors (Lorenz, Duffing, Hennon and etc.). We have shown on the standard 5-min segments from MIT-BIH database of HRV records: - the statistically significant difference of D2 for cases of normal sinus rhythm and congestive heart failure; - D2 drop significantly for the about 30 min. before of AF and D2 growth drastically under AF there was shown for HRV records with Atrial Fibrillation (AF) episodes. The suggested robust correlation dimension D2 estimator is perfect suitable for real time HRV monitoring as accurate, fast and non-consuming for computing resources. Key words: Hearth rate variability; Correlation dimension; Congestive heart failure; Atrial fibrillation.

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