Artificial intelligence analysis of ECG signals to predict arrhythmia recurrence after cryoballoon ablation of atrial fibrillation

Introduction

Cryoballoon-based pulmonary vein isolation (CB) is an effective option for rhythm control in atrial fibrillation (AF). There have been multiple attempts to predict arrhythmia recurrence, but with moderate success.

Purpose

To use artificial intelligence (AI) deep electrocardiogram (ECG) analysis to predict arrythmia recurrence after CB.

Methods

In a single-center study of 250 consecutive pts (58.2±12.6 years, 30% female) treated with CB for AF (05.2017–04.2019), 60% had paroxysmal AF (PAF), 66.5% had hypertension, and 27.2% had a redo CB. Analyses included left atrial volume (LA vol: indexed for BSA and assed by angio-MSCT in 76% and the rest with echo), left ventricle ejection fraction (LVEF) and hypertrophy (LVH: septal/posterior wall thickness ≥11mm in ♂ and ≥10mm in ♀) along with 30s arrhythmia recurrence at 2-yr follow-up. Baseline 500Hz raw 12-lead digital ECG signals were analyzed by means of convolutional neural network (CNN) architecture that was taught to process the 12-channel ECG signal (XML). The transfer learning method of CNN parameters learned on a very large number of coded consecutive training ECG samples (n=1,000) was adopted to analyze current sample of ECG signals.

Results

Arrhythmia recurrence at 2-yrs was 46.0% (n=115). There was gradual increase in predictive performance being the lowest if only baseline clinical data were analyzed and the highest combing all baseline clinical data plus anatomical and functional parameters (Table 1: #1–#3). AI baseline ECG analysis alone offered predictive performance similar to that made upon analysis of all baseline clinical data or joint analysis of LA vol, LVH, and LVEF (Table 1: #4). AI results added substantially to predictive performance of models using baseline clinical data alone (#1 vs #5, p<0.001) and joint analysis of baseline clinical plus LA vol, LVH and LVEF (#3 vs #6, p=0.0130) (Fig. 1).

Conclusions

Prediction of recurrence after CB using raw ECG data with deep AI analysis is feasible. Joint analysis of results of AI of baseline ECG and basic clinical data offers predictive performance similar to that made upon analysis of clinical data including advanced information on LA volume and LVH and function. AI analysis of baseline ECG adds significantly to models aimed at recurrent AF prediction.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): National Institute of Cardiology, Warsaw, Poland

DIABETIC KETOACIDOSIS WITH AN ACUTE ABDOMEN AS A FIRST MANIFESTATION OF TYPE 1 DIABETES MELLITUS

Context

Diabetic pseudoperitonitis is a very rare complication of the type 1 diabetes mellitus and it is associated with a severe ketoacidosis. The exact pathogenesis of the status is still unclear, the typical presentation is an acute abdomen by the patient. To confirm the diagnosis, it is necessary to make examinations, which exclude other possible reason of an acute abdomen by the patient (laboratory tests, abdominal ultrasound or a CT scan).

Case presentation

A 46-years old man was admitted to the hospital wih a history of a 10 days epigastric pain. Laboratory tests, abdominal ultrasound, CT scan and upper endoscopy were performed, the reason of the pain remained unclear. Because of the peritoneal signs at the first day of the hospitalisation an acute surgery was indicated, without any pathology at the laparoscopy. A severe metabolic acidosis was recognized only after the surgery, the initial hypoglycaemia rose up after giving a total parenteral nutrition to the patient. The increase of the glycaemia, the severe metabolic acidosis with glycosuria and ketonuria, and the elevation of the glycated haemoglobin brought us to the diagnosis of the new onset of the diabetes.

Conclusion

Diabetic pseudoperitonitis with the picture of an acute abdomen can occur as a first manifestation of the diabetes. Thinking of this rare complication and recognising it can avoid unnecessary acute surgery by the patient.

Safety and on-treatment efficacy of telaprevir: the early access programme for patients with advanced hepatitis C

BACKGROUND AND AIM

Severe adverse events (AEs) compromise the outcome of direct antiviral agent-based treatment in patients with advanced liver fibrosis due to HCV infection. HEP3002 is an ongoing multinational programme to evaluate safety and efficacy of telaprevir (TVR) plus pegylated-interferon-α (PEG-IFNα) and ribavirin (RBV) in patients with advanced liver fibrosis caused by HCV genotype 1 (HCV-1).

METHODS

1782 patients with HCV-1 and bridging fibrosis or compensated cirrhosis were prospectively recruited from 16 countries worldwide, and treated with 12 weeks of TVR plus PEG-IFN/RBV, followed by 12 or 36 weeks of PEG-IFN and RBV (PR) alone dependent on virological response to treatment and previous response type.

RESULTS

1587 patients completed 12 weeks of triple therapy and 4 weeks of PR tail (53% cirrhosis, 22% HCV-1a). By week 12, HCV RNA was undetectable in 85% of naives, 88% of relapsers, 80% of partial responders and 72% of null responders. Overall, 931 patients (59%) developed grade 1-4 anaemia (grade 3/4 in 31%), 630 (40%) dose reduced RBV, 332 (21%) received erythropoietin and 157 (10%) were transfused. Age and female gender were the strongest predictors of anaemia. 64 patients (4%) developed a grade 3/4 rash. Discontinuation of TVR due to AEs was necessary in 193 patients (12%). Seven patients died (0.4%, six had cirrhosis).

CONCLUSIONS

In compensated patients with advanced fibrosis due to HCV-1, triple therapy with TVR led to satisfactory rates of safety, tolerability and on-treatment virological response with adequate managements of AEs.

Historical epidemiology of hepatitis C virus (HCV) in selected countries

Chronic infection with hepatitis C virus (HCV) is a leading indicator for liver disease. New treatment options are becoming available, and there is a need to characterize the epidemiology and disease burden of HCV. Data for prevalence, viremia, genotype, diagnosis and treatment were obtained through literature searches and expert consensus for 16 countries. For some countries, data from centralized registries were used to estimate diagnosis and treatment rates. Data for the number of liver transplants and the proportion attributable to HCV were obtained from centralized databases. Viremic prevalence estimates varied widely between countries, ranging from 0.3% in Austria, England and Germany to 8.5% in Egypt. The largest viremic populations were in Egypt, with 6,358,000 cases in 2008 and Brazil with 2,106,000 cases in 2007. The age distribution of cases differed between countries. In most countries, prevalence rates were higher among males, reflecting higher rates of injection drug use. Diagnosis, treatment and transplant levels also differed considerably between countries. Reliable estimates characterizing HCV-infected populations are critical for addressing HCV-related morbidity and mortality. There is a need to quantify the burden of chronic HCV infection at the national level.

The present and future disease burden of hepatitis C virus (HCV) infection with today's treatment paradigm

The disease burden of hepatitis C virus (HCV) is expected to increase as the infected population ages. A modelling approach was used to estimate the total number of viremic infections, diagnosed, treated and new infections in 2013. In addition, the model was used to estimate the change in the total number of HCV infections, the disease progression and mortality in 2013-2030. Finally, expert panel consensus was used to capture current treatment practices in each country. Using today's treatment paradigm, the total number of HCV infections is projected to decline or remain flat in all countries studied. However, in the same time period, the number of individuals with late-stage liver disease is projected to increase. This study concluded that the current treatment rate and efficacy are not sufficient to manage the disease burden of HCV. Thus, alternative strategies are required to keep the number of HCV individuals with advanced liver disease and liver-related deaths from increasing.

Strategies to manage hepatitis C virus (HCV) disease burden

The number of hepatitis C virus (HCV) infections is projected to decline while those with advanced liver disease will increase. A modeling approach was used to forecast two treatment scenarios: (i) the impact of increased treatment efficacy while keeping the number of treated patients constant and (ii) increasing efficacy and treatment rate. This analysis suggests that successful diagnosis and treatment of a small proportion of patients can contribute significantly to the reduction of disease burden in the countries studied. The largest reduction in HCV-related morbidity and mortality occurs when increased treatment is combined with higher efficacy therapies, generally in combination with increased diagnosis. With a treatment rate of approximately 10%, this analysis suggests it is possible to achieve elimination of HCV (defined as a >90% decline in total infections by 2030). However, for most countries presented, this will require a 3-5 fold increase in diagnosis and/or treatment. Thus, building the public health and clinical provider capacity for improved diagnosis and treatment will be critical.

Anemia as a predictor of response to antiviral therapy in chronic hepatitis C

BACKGROUND

The standard therapy for chronic HCV infection is the administration of pegylated interferons in combination with ribavirin. Anemia is a dose-dependent side-effect of ribavirin administration. The degree of anemia could be indicative of the individual exposure to ribavirin.

AIMS

1) To evaluate the correlation of HGB level decreases at specified time-points with a sustained virological response during the antiviral treatment. 2) To compare these parameters with the virological predictors for responses.

METHODS

A retrospective analysis of cohort, which comprised 164 patients treated with standard therapy at a tertiary center in Prague, Czech Republic.

RESULTS

We identified several predictive factors for a sustained virological response in females: baseline HGB level ≤140 g/l (p=0.025), maximum drop from baseline >40 g (p=0.039), and a HGB drop in week 4 >30 g (p=0.044). There was only one predictor identified for males: reaching the lowest HGB level after week 19 (p=0.021). The strongest positive predictor of response was a rapid virological response. A low viral load (<600 000 IU/ml) at baseline was not associated with a sustained response in either gender.

CONCLUSIONS

The parameters of HGB decrease during antiviral treatment are better correlated with a sustained response in females. None of these response predicting parameters was as significant as that of rapid virological response as that of rapid virological response (Tab. 4, Fig. 1, Ref. 15).

Double-blind randomized, comparative multicenter study of the effect of terlipressin in the treatment of acute esophageal variceal and/or hypertensive gastropathy bleeding

BACKGROUND/AIMS

1) To compare the effect of 2-day application of 0.2 mg terlipressin i.v. every 4 hours (group I) with that of 5-day application of 1 mg i.v. every 4 hours (group II) in the treatment of bleeding esophageal varices and portal gastropathy. 2) To assess the incidence of adverse events.

METHODOLOGY

Eighty-six patients with liver cirrhosis (54 men and 32 women, average age 51 years) were randomized over a period of 2 years into 2 groups. Acute bleeding was diagnosed endoscopically within 24 hours of its onset. The two groups fully comparable; treatment failure rated according to "Baveno II".

RESULTS

Success rate in group I was 78% at day 2 and 75% at day 5; in group II 89% and 79%, respectively (no statistical significance). Rebleeding had occurred by day 5 in 15% in group I, and in 16.3% in group II. Transfusion needs by day 2 were significantly lower in group II (2.4 units compare to 3.4 units in I). The 30-day mortality was 17.1% in group I and 20% in group II. No statistical difference between I and II in the occurrence of adverse events.

CONCLUSIONS

At a dosage of 1 mg i.v. every 4 hours, the success rate at day 2 was as much as 90% while blood consumption was significantly lower compared with the lower dosage. Rebleeding during first 48 hours occurred almost exclusively at lower dosage. There was no increase in the rate of adverse events relative to the higher dosage.

Intraluminal brachytherapy and selfexpandable stents in nonresectable biliary malignancies--the question of long-term palliation

BACKGROUND/AIMS

To evaluate the effect of a combination of intraluminal brachytherapy and metallic stent implantation in the treatment of patients with nonresectable biliary tumors.

METHODOLOGY

Thirty-two patients aged 41-80 years with nonresectable biliary malignancies--Klatskin's tumor (n = 17), gallbladder carcinoma (n = 11) and carcinoma of papilla Vateri (n = 4)--were treated with a combination of intraluminal brachytherapy (source Ir192, high-dose radiation regimen, total dose 30 Gy) and metallic stent implantation. Intraluminal brachytherapy and stent insertion (metallic, spiral-Z stent) were performed percutaneously in all patients.

RESULTS

The mean survival in patients with Klatskin's tumor was 457 days (range: 64-1186; median: 358 days), in patients with gallbladder carcinoma 237 days (range: 92-609; median: 210 days) and in patients with carcinoma of papilla Vateri 850 days (range: 48-1518; median: 1277 days). The rate of 2-year survival in these groups as 27, 0 and 50%, respectively. The survival time differed significantly at the 5% level. The mean time of stent patency was 418, 220 and 850 days, respectively. No complications related directly to intraluminal brachytherapy were observed.

CONCLUSIONS

Intraluminal brachytherapy combined with stent implantation is a safe method and appears to prolong survival in inoperable patients with Klatskin's tumor and carcinoma of papilla Vateri compared with nontreated patients in previous studies. In contrast no similar effect should be expected in patients with gallbladder carcinoma.

Significant reduction of air microbubbles with the dynamic bubble trap during cardiopulmonary bypass

Air microbubbles mostly occur unnoticed during cardiopulmonary bypass and are predominantly responsible for serious postoperative psychoneurological dysfunction. A dynamic bubble trap (DBT), which removes air microbubbles from the arterial blood, was tested in a clinical study. The aim was to evaluate the efficiency of microbubble removal under clinical conditions. As blood passes through the DBT, which is placed in the arterial line between the arterial filter and arterial cannula, it is converted into a rotating stream. The bubbles are directed to the centre of the blood flow and are collected in the distal end of the DBT, from where they are returned to the cardiotomy reservoir. Doppler ultrasonography was used to detect the microbubbles before and after the DBT, and also the number of high-intensity transient signals (HITS) in the right and left middle cerebral artery during extracorporeal circulation. A significant reduction of microbubbles in the arterial line (3,990 before DBT, 537 after, p < 0.001) and HITS in the brain (51 in the DBT group, 77 in the placebo group, p = 0.04) was measured.

A dynamic bubble trap reduces microbubbles during cardiopulmonary bypass: a case study

Microemboli passing to the cerebral circulation during cardiopulmonary bypass can contribute to postoperative neurologic dysfunction. Many studies conclude that air microbubbles predominantly are responsible for this problem. A dynamic bubble trap (DBT) was developed to diminish the number of microbubbles in the arterial line of extracorporeal circulation. The DBT is able to substantially reduce the number of air microbubbles, as shown in two patients undergoing coronary artery bypass grafting, where a high number of microbubbles was assessed. Although a 40-micron arterial filter was used, many bubbles larger than 40 microns occurred in the arterial line. The DBT reduced the number of large microbubbles from 2,267 to 67 in patient 1 and from 897 to 61 in patient 2.

Percutaneous cardiopulmonary support (PCPS)

The cardiopulmonary support system allows to maintain the patient's cardiac and pulmonary functions when the patient's cardiac or pulmonary status is failing. This system consists of a centrifugal pump with its control system, membrane oxygenator, measure devices for blood flow and pressure and a heating system for temperature conditioning of blood. The percutaneous application is easy and fast. Rapid priming, rapid insertion and high flow rates are characteristic for this method. The material costs for cardiac support of one patient are high, the price for one patient amounts to approximately DM 3,500. For the application the presence of an operating cardiologist, an anesthetist and a perfusionist is necessary.

Diminished release of atrial natriuretic factor in calves with a total artificial heart

Venous hypertension after total artificial heart (TAH) replacement, a common problem in humans as well as experimental animals, is thought to be related to reduced release of atrial natriuretic factor (ANF) due to atrial damage. To verify this hypothesis, we stimulated the release of ANF in 6 calves before (-7 days) and after TAH replacement (+25, +50, +80, and +100 days) by the rapid (+ = 10 min) infusion of 2 L of Ringer's solution. In normal calves (-7 days) this procedure induced a rise in plasma concentration of ANF from 18.5 +/- 12 to 31.6 +/- 12 pmol/L (p < 0.05). After TAH the ANF release continuously decreased (analysis of variance, p < 0.02). Thus, ANF increased by 9.8 +/- 9.3, 6.8 +/- 17.5, 0.4 +/- 5.2, and 0.5 +/- 3.2 pmol/L at days 25, 50, 80, and 100, respectively. The central venous pressure increased by 3.4 +/- 1.5 mm Hg (before TAH) and by 6 +/- 2.9 mm Hg (after TAH) during this procedure. A decrease in plasma concentrations of aldosterone, most likely due to extracellular volume expansion and a decrease in total protein plasma concentrations and in hematocrit due to the dilution of blood, was seen in each experiment. Necropsy demonstrated massive atrial dilatation and myocardial dystrophy with atrial fibrosis. ANF granules were present to a small extent in every calf. We conclude that rapid intravenous infusion is an adequate stimulus to release ANF in normal calves. After TAH implantation the release of ANF by high venous pressure declines although ANF granules are still present in the damaged atrial stumps. Therefore, the loss of stimulated ANF could contribute to the observed increase in venous pressure in TAH calves although other pathophysiologic mechanisms cannot be excluded.