Transcriptomic and spatial dissection of human ex vivo right atrial tissue reveals proinflammatory microvascular changes in ischemic heart disease.

Cardiovascular disease plays a central role in the electrical and structural remodeling of the right atrium, predisposing to arrhythmias, heart failure, and sudden death. Here, we dissect with single-nuclei RNA sequencing (snRNA-seq) and spatial transcriptomics the gene expression changes in the human ex vivo right atrial tissue and pericardial fluid in ischemic heart disease, myocardial infarction, and ischemic and non-ischemic heart failure using asymptomatic patients with valvular disease who undergo preventive surgery as the control group. We reveal substantial differences in disease-associated gene expression in all cell types, collectively suggesting inflammatory microvascular dysfunction and changes in the right atrial tissue composition as the valvular and vascular diseases progress into heart failure. The data collectively suggest that investigation of human cardiovascular disease should expand to all functionally important parts of the heart, which may help us to identify mechanisms promoting more severe types of the disease.

Elective Cardiac Procedure Patients Have Low Preoperative Cardiorespiratory Fitness.

Preoperative cardiorespiratory fitness may influence the recovery after cardiac procedure. The aim of this study was to investigate the cardiorespiratory fitness of patients scheduled for elective cardiac procedures, using a six-minute walk test, and compare the results with a population-based sample of Finnish adults. Patients (n=234) awaiting percutaneous coronary intervention or coronary angiography, coronary artery bypass grafting, aortic valve replacement or mitral valve surgery performed the six-minute walk test. VO2max was calculated based on the walk test. The patients were compared to a population-based sample of 60-69-year-old Finnish adults from the FinFit2017 study. The mean six-minute walk test distances (meters) and VO2max (ml/kg/min) of the patient groups were: 452±73 and 24.3±6.9 (coronary artery bypass grafting), 499±84 and 27.6±7.2 (aortic valve replacement), 496±85 and 27.4±7.3 (mitral valve surgery), and 519±90 and 27.3±6.9 (percutaneous coronary intervention or coronary angiography). The population-based sample had significantly greater walk test distance (623±81) and VO2max (31.7±6.1) than the four patient groups (all p-values<0.001). All patient groups had lower cardiorespiratory fitness than the reference population of 60-69-year-old Finnish adults. Particularly the coronary artery bypass grafting group had a low cardiorespiratory fitness, and therefore might be prone to complications and challenging rehabilitation after the operation.

Sex Differences in Red Blood Cell Transfusions and 30-Day Mortality in Cardiac Surgery: A Single Center Observational Study.

In cardiac surgery, women have higher short-term mortality and a higher risk of receiving red blood cell (RBC) transfusions than men. This study's aim was to evaluate possible sex differences in RBC transfusions in cardiac surgery and their association with preoperative hemoglobin levels, body mass index, and 30-day mortality. A single-center retrospective study was conducted with 1583 patients (1181 men and 402 women) undergoing cardiac surgery. A total of 64.4% of the women and 33.0% of the men received an RBC transfusion. In a multivariable analysis, female sex was an independent predictor of RBC transfusion (OR 3.88, 95% CI 2.95-5.11, p < 0.001). Other independent predictors of RBC transfusion were age, preoperative hemoglobin level, and body mass index. The women were more likely to receive RBC transfusions than the men, regardless of the type of cardiac surgery. Decreased transfusion risk was found in all higher-than-normal weight categories in the women, but only in the severe obesity category in the men. Preoperative hemoglobin was similarly associated with RBC transfusion in the men and women. The crude 30-day mortality rate was higher in the women than in the men (2.5% vs. 0.9%, p = 0.018). In both sexes, RBC transfusion was associated with an increased probability of death within 30 days.

Association of body mass index with 30-day mortality and red blood cell transfusions in open heart surgery.

OBJECTIVES: Obesity is associated with increased burden of cardiovascular risk factors, morbidity and mortality. However, several studies have counterintuitively shown better outcome after cardiac surgery in obese than in normal weight patients, a phenomenon known as obesity paradox. Furthermore, obesity has been linked with decreased need of red blood cell (RBC) transfusions. The purpose of this study was to evaluate the impact of body mass index (BMI) on 30-day mortality and RBC transfusions in patients undergoing cardiac surgery, a clinically important topic with conflicting previous data. METHODS: We retrospectively investigated 1691 patients who underwent coronary and/or valve or aortic root surgery using cardiopulmonary bypass between 2013 and 2016. The patients were categorized by BMI based on the World Health Organization classification. For analysis, logistic regression was used with adjustment for potential confounding factors. RESULTS: Of the patients, 28.7% were normal weight, 43.3% overweight, 20.5% mildly obese and 7.5% severely obese. Thirty-day mortality was 1.9% without significant differences between the BMI groups. 41.0% of patients received RBC transfusion. Overweight [odds ratio (OR) 0.75, 95% confidence interval (CI) 0.56-0.99, P = 0.045], mildly (OR 0.65, 95% CI 0.46-0.92, P = 0.016) and severely obese (OR 0.41, 95% CI 0.24-0.70, P = 0.001) patients needed less frequently RBC transfusions than patients with normal weight. CONCLUSIONS: Obesity was not associated with 30-day mortality but was associated with lower use of RBC transfusions in cardiac surgery.

Novel Technologies in the Detection of Atrial Fibrillation: Review of Literature and Comparison of Different Novel Technologies for Screening of Atrial Fibrillation.

Atrial fibrillation (AF) is globally the most common arrhythmia associated with significant morbidity and mortality. It impairs the quality of the patient's life, imposing a remarkable burden on public health, and the healthcare budget. The detection of AF is important in the decision to initiate anticoagulation therapy to prevent thromboembolic events. Nonetheless, AF detection is still a major clinical challenge as AF is often paroxysmal and asymptomatic. AF screening recommendations include opportunistic or systematic screening in patients ≥65 years of age or in those individuals with other characteristics pointing to an increased risk of stroke. The popularities of well-being and taking personal responsibility for one's own health are reflected in the continuous development and growth of mobile health technologies. These novel mobile health technologies could provide a cost-effective solution for AF screening and an additional opportunity to detect AF, particularly its paroxysmal and asymptomatic forms.

Impact of minimal invasive extracorporeal circulation on perioperative intravenous fluid management in coronary artery bypass surgery.

OBJECTIVE: Compare the use of blood products and intravenous fluid management in patients scheduled for coronary artery bypass surgery and randomized to minimal invasive extracorporeal circulation (MiECC) and conventional extracorporeal circulation (CECC). METHODS: A total of 240 patients who were scheduled for their first on-pump CABG, were randomized to MiECC or CECC groups. The study period was the first 84 hours after surgery. Hemoglobin <80 g/l was used as transfusion trigger. RESULTS: Red blood cell transfusions intraoperatively were given less often in the MiECC group (23.3% vs 9.2%, p = 0.005) and the total intravenous fluid intake was significantly lower in the MiECC group (3300 ml [2950-4000] vs 4800 ml [4000-5500], p < 0.001). Hemoglobin drop also was lower in the MiECC group (35.5 ± 8.9 g/l vs 50.7 ± 9 g/l, p < 0.001) as was hemoglobin drop percent (25.3 ± 6% vs 35.3 ± 5.9%, p < 0.001). Chest tube drainage output was higher in the MiECC group (645 ml [500-917.5] vs 550 ml [412.5-750], p = 0.001). Particularly, chest tube drainage in up to 600 ml category, was in benefit of CECC group (59.1% vs 40.8%, p = 0.003). ROC curve analysis showed that patients with hemoglobin level below 95 g/l upon arrival to intensive care unit was associated with increased risk of developing postoperative atrial fibrillation (POAF) (p = 0.002, auc = 0.61, cutoff <95, sensitivity = 0.47, positive predictive value = 0.64). CONCLUSION: MiECC reduced the intraoperative need for RBC transfusion and intravenous fluids compared to the CECC group, also reducing hemoglobin drop compared to the CECC group in CABG surgery patients. Postoperative hemoglobin drop was a predictor of POAF.

Impact of perfusion method on perioperative red blood cell transfusions and new-onset postoperative atrial fibrillation in mitral valve surgery patients.

INTRODUCTION: Red blood cell (RBC) transfusions are common in cardiac surgery and reportedly associated with increased mortality and morbidity, including increased risk of postoperative new-onset atrial fibrillation (NOAF). The aim of this study was to compare minimal invasive extracorporeal circulation (MiECC) and conventional extracorporeal circulation (CECC) in terms of RBC transfusions and the incidence of NOAF in mitral valve surgery. METHODS: The study population consisted of 89 MiECC and 169 CECC patients undergoing mitral valve surgery as an isolated procedure (80.6% of the patients) or in combination with coronary artery bypass grafting (19.4% of patients). 79.4% of the patients were male and the mean age was 62.1 years. RESULTS: 30.0% of patients aged < 65 years and 48.1% of patients aged ≥ 65 years needed RBC transfusion. The overall need for RBC transfusions did not differ between the treatment groups. Among patients < 65 years of age transfusions of ≥ 3 units were less frequent in MiECC than in CECC patients (OR 0.31, 95% CI 0.10-0.98, p = 0.045). The overall incidence of NOAF was 41.8% with no significant difference between MiECC and CECC groups. Red blood cell transfusions were associated with an increased risk of NOAF in an unadjusted analysis but not after adjustment for age and sex (OR 1.25, 95% CI 0.64-2.43, p = 0.515). CONCLUSIONS: In mitral valve surgery MiECC compared to CECC was associated with less need of RBC units and platelets, particularly in patients aged < 65 years. Use of RBC transfusions was associated with increased risk of NOAF significantly only in unadjusted analysis.

Objectively measured preoperative physical activity and sedentary behaviour among Finnish patients scheduled for elective cardiac procedures: baseline results from randomized controlled trial.

BACKGROUND: We investigated preoperative physical activity (PA) and sedentary behaviour (SB) in patients scheduled for elective cardiac procedures and compared them with population-based sample of Finnish adults. METHODS: Cardiac patients (n = 139) undergoing cardiac operations carried a triaxial accelerometer for seven days during the month before the procedure. Patients were categorised into four groups according to the procedure: percutaneous coronary intervention or coronary angiography (PCI-CA), coronary artery bypass grafting (CABG), aortic valve replacement (AVR) and mitral valve surgery (MVS). The raw accelerometer data was analyzed with dedicated algorithms to determine metabolic equivalents (METs, 3.5 mL/kg/min of oxygen consumption) of PA. The intensity of PA was divided into two categories: light (LPA, 1.5-2.9 METs) and moderate-to-vigorous (MVPA, ≥ 3.0 METs), while SB represented intensity < 1.5 MET without movements. SB and PA were described as daily means and accumulation from different bout lengths. Daily standing, steps and mean and peak MET-values were calculated. The results were compared between the patient groups and against the reference group from a population-based study FinFit2017. RESULTS: Cardiac patients had fewer daily steps than the FinFit population (p = 0.01), and less SB accumulating from < 20 min bouts (p = 0.002) but more from 20 to 60 min bouts (p = 0.002). Particularly, CABG group had less daily MVPA (p = 0.002) and MVPA accumulating from > 10 min bouts (p < 0.001) than the FinFit population. CONCLUSIONS: We found large differences in PA and SB between the patient groups and the FitFit population, CABG group having the worst activity profile. Also, the variation within the patient groups was wide, which should be considered to individualise the rehabilitation programs postoperatively. Trial registration clinicaltrials.gov (NCT03470246). Registered 19 March 2018, https://clinicaltrials.gov/ct2/show/NCT03470246.

Continuous mHealth Patch Monitoring for the Algorithm-Based Detection of Atrial Fibrillation: Feasibility and Diagnostic Accuracy Study.

BACKGROUND: The detection of atrial fibrillation (AF) is a major clinical challenge as AF is often paroxysmal and asymptomatic. Novel mobile health (mHealth) technologies could provide a cost-effective and reliable solution for AF screening. However, many of these techniques have not been clinically validated. OBJECTIVE: The purpose of this study is to evaluate the feasibility and reliability of artificial intelligence (AI) arrhythmia analysis for AF detection with an mHealth patch device designed for personal well-being. METHODS: Patients (N=178) with an AF (n=79, 44%) or sinus rhythm (n=99, 56%) were recruited from the emergency care department. A single-lead, 24-hour, electrocardiogram-based heart rate variability (HRV) measurement was recorded with the mHealth patch device and analyzed with a novel AI arrhythmia analysis software. Simultaneously registered 3-lead electrocardiograms (Holter) served as the gold standard for the final rhythm diagnostics. RESULTS: Of the HRV data produced by the single-lead mHealth patch, 81.5% (3099/3802 hours) were interpretable, and the subject-based median for interpretable HRV data was 99% (25th percentile=77% and 75th percentile=100%). The AI arrhythmia detection algorithm detected AF correctly in all patients in the AF group and suggested the presence of AF in 5 patients in the control group, resulting in a subject-based AF detection accuracy of 97.2%, a sensitivity of 100%, and a specificity of 94.9%. The time-based AF detection accuracy, sensitivity, and specificity of the AI arrhythmia detection algorithm were 98.7%, 99.6%, and 98.0%, respectively. CONCLUSIONS: The 24-hour HRV monitoring by the mHealth patch device enabled accurate automatic AF detection. Thus, the wearable mHealth patch device with AI arrhythmia analysis is a novel method for AF screening. TRIAL REGISTRATION: ClinicalTrials.gov NCT03507335; https://clinicaltrials.gov/ct2/show/NCT03507335.

Use of paclitaxel-coated balloons in clinical setting is not associated with increased mortality compared with plain balloon angioplasty in femoropopliteal lesions.

OBJECTIVE: To investigate mortality and causes of death associated with the use of paclitaxel-coated balloon (PCB) compared with plain balloon (PB) angioplasty in the treatment of femoropopliteal artery lesions in real-world clinical setting. METHODS: This retrospective, single-center study included patients who underwent percutaneous femoropopliteal artery angioplasty without stenting between years 2014 and 2020. Patients were stratified into PCB and PB groups according to the index procedure. Those who had undergone any prior or subsequent intervention using drug-eluting technology were excluded from the PB group. Long-term survival was estimated up to 5 years using the Kaplan-Meier method, and risk factors for all-cause mortality were assessed in a multivariable analysis. Causes of death were retrieved from a national registry. RESULTS: The study included 139 patients treated with PB and 190 with PCB. Patients treated with PCB had a higher prevalence of chronic pulmonary disease (27% vs 17%; P = .02) and were less often on anticoagulant therapy (34% vs 48%; P = .01) compared with patients in the PB group. Those treated with PB were more likely to have chronic limb-threatening ischemia (CLTI; 82% vs 72%; P = .04). Ipsilateral perioperative amputation rate was significantly higher in the PB group (7% vs 1%; P = .01). There were no major differences in other 30-day outcomes between the groups and no differences in the rates of reinterventions and ipsilateral amputations during a mean follow-up time of 2.7 ± 1.9 years. Survival at 1 year in the PCB group was 83% ± 3% compared with 73% ± 4% in the PB group (P = .0001). The 5-year survival estimates were 56% ± 5% and 37% ± 5%, respectively. PCB use was independently associated with decreased risk of mortality (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.50-0.97). Independent risk factors for increased mortality were age (HR, 1.04 per year; 95% CI, 1.02-1.06), cardiac insufficiency (HR, 1.60; 95% CI, 1.12-2.27), chronic renal insufficiency (HR, 2.04; 95% CI, 1.47-2.85), anticoagulation therapy (HR, 1.65, 95% CI, 1.16-2.34), and CLTI (HR, 2.85; 95% CI, 1.51-5.39). In the PCB group, 63% of deaths were due to cardiovascular causes compared with 42% in the PB group (P < .01). CONCLUSIONS: The use of PCB is safe, and there is no concern of increased mortality after the procedure based on the 5-year survival estimates.

Decreasing complications of pectoralis major muscle flap reconstruction with two modalities of negative pressure wound therapy.

BACKGROUND AND OBJECTIVE: Deep sternal wound infection is a feared complication of open-heart surgery. Negative pressure wound therapy has gained an important role in the treatment of deep sternal wound infection. Incisional negative pressure wound therapy has been introduced as a method to prevent wound complications after sternotomy, and lately, after flap reconstructions in the treatment of deep sternal wound infection. We aimed to study if incisional negative pressure wound therapy with PICO™ had similar beneficial effect described earlier with competing commercial devices. METHODS: This study included 82 patients treated with pectoralis major muscle flap for deep sternal wound infection during the years 2006-2020. PICO group consisted of 24 patients treated with preoperative negative pressure wound therapy and postoperative incisional negative pressure wound therapy (PICO™). Two control groups included 48 patients with conventional treatment and 10 patients with preoperative negative pressure wound therapy only. RESULTS: In the PICO group, the complication rate declined from 50.0% to 33.30%, major complication rate from 29.2% to 12.5%, and need for an additional flap from 14.6.% to 4.2% when compared to conventional treatment. The length of hospital stay decreased as well. Preoperative negative pressure wound therapy alone was associated with moderate decline in the complication rates. In addition, we described the use of split pectoralis major muscle flap reconstruction in 57 patients. To our knowledge, this is the largest published patient series describing this method in the treatment of deep sternal wound infection. CONCLUSIONS: Incisional negative pressure wound therapy with PICO™ seems beneficial after flap reconstruction. Split pectoralis major muscle flap is a versatile reconstruction option suitable to be used as a workhorse in the treatment of deep sternal wound infection.

Does Incisional Negative Pressure Wound Therapy Prevent Sternal Wound Infections?

BACKGROUND: Incisional negative pressure wound therapy has been described as an effective method to prevent wound infections after open heart surgery in several publications. However, most studies have examined relatively small patient groups, only a few were randomized, and some have manufacturer-sponsorship. Most of the studies have utilized Prevena; there are only a few reports describing the PICO incisional negative pressure wound therapy system. METHODS: We conducted a prospective cohort study involving a propensity score-matched analysis to evaluate the effect of PICO incisional negative pressure wound therapy after coronary artery bypass grafting. A total of 180 high-risk patients with obesity or diabetes were included in the study group. The control group included 772 high-risk patients operated before the initiation of the study protocol. RESULTS: The rates of deep sternal wound infections in the PICO group and in the control group were 3.9 and 3.1%, respectively. The rates of superficial wound infections needing operative treatment were 3.1 and 0.8%, respectively. After propensity score matching with two groups of 174 patients, the incidence of both deep and superficial infections remained slightly elevated in the PICO group. None of the infections were due to technical difficulties or early interruption of the treatment. CONCLUSION: It seems that incisional negative pressure wound therapy with PICO is not effective in preventing wound infections after coronary artery bypass grafting. The main difference in this study compared with previous reports is the relatively low incidence of infections in our control group.

Prevention of Atrial Fibrillation After Cardiac Surgery: A Review of Literature and Comparison of Different Treatment Modalities.

Atrial fibrillation is the most common arrhythmia to occur after cardiac surgery, with an incidence of 10% to 50%. It is associated with postoperative complications including increased risk of stroke, prolonged hospital stays and increased costs. Despite new insights into the mechanisms of atrial fibrillation, no specific etiologic factor has been identified as the sole perpetrator of the arrhythmia. Current evidence suggests that the pathophysiology of atrial fibrillation in general, as well as after cardiac surgery, is multifactorial. Studies have also shown that new-onset postoperative atrial fibrillation following cardiac surgery is associated with a higher risk of short-term and long-term mortality. Furthermore, it has been demonstrated that prophylactic medical therapy decreases the incidence of postoperative atrial fibrillation after cardiac surgery. Of note, the incidence of postoperative atrial fibrillation has not changed during the last decades despite the numerous preventive strategies and operative techniques proposed, although the perioperative and postoperative care of cardiac patients as such has improved.

Automatic Mobile Health Arrhythmia Monitoring for the Detection of Atrial Fibrillation: Prospective Feasibility, Accuracy, and User Experience Study.

BACKGROUND: Atrial fibrillation (AF) is the most common tachyarrhythmia and associated with a risk of stroke. The detection and diagnosis of AF represent a major clinical challenge due to AF's asymptomatic and intermittent nature. Novel consumer-grade mobile health (mHealth) products with automatic arrhythmia detection could be an option for long-term electrocardiogram (ECG)-based rhythm monitoring and AF detection. OBJECTIVE: We evaluated the feasibility and accuracy of a wearable automated mHealth arrhythmia monitoring system, including a consumer-grade, single-lead heart rate belt ECG device (heart belt), a mobile phone application, and a cloud service with an artificial intelligence (AI) arrhythmia detection algorithm for AF detection. The specific aim of this proof-of-concept study was to test the feasibility of the entire sequence of operations from ECG recording to AI arrhythmia analysis and ultimately to final AF detection. METHODS: Patients (n=159) with an AF (n=73) or sinus rhythm (n=86) were recruited from the emergency department. A single-lead heart belt ECG was recorded for 24 hours. Simultaneously registered 3-lead ECGs (Holter) served as the gold standard for the final rhythm diagnostics and as a reference device in a user experience survey with patients over 65 years of age (high-risk group). RESULTS: The heart belt provided a high-quality ECG recording for visual interpretation resulting in 100% accuracy, sensitivity, and specificity of AF detection. The accuracy of AF detection with the automatic AI arrhythmia detection from the heart belt ECG recording was also high (97.5%), and the sensitivity and specificity were 100% and 95.4%, respectively. The correlation between the automatic estimated AF burden and the true AF burden from Holter recording was >0.99 with a mean burden error of 0.05 (SD 0.26) hours. The heart belt demonstrated good user experience and did not significantly interfere with the patient's daily activities. The patients preferred the heart belt over Holter ECG for rhythm monitoring (85/110, 77% heart belt vs 77/109, 71% Holter, P=.049). CONCLUSIONS: A consumer-grade, single-lead ECG heart belt provided good-quality ECG for rhythm diagnosis. The mHealth arrhythmia monitoring system, consisting of heart-belt ECG, a mobile phone application, and an automated AF detection achieved AF detection with high accuracy, sensitivity, and specificity. In addition, the mHealth arrhythmia monitoring system showed good user experience. TRIAL REGISTRATION: ClinicalTrials.gov NCT03507335; https://clinicaltrials.gov/ct2/show/NCT03507335.

Physical activity and sedentary behaviour in secondary prevention of coronary artery disease: A review.

Comprehensive management of coronary artery disease (CAD) includes physical exercise as a part of daily lifestyle therapy. Still CAD patients generally have low physical activity (PA) and high sedentary behaviour (SB). This review summarizes the effect of exercise training and habitual PA and SB on physical fitness and quality of life (QoL) as well as on rehospitalizations and mortality in patients with stable CAD, recent acute coronary syndrome (ACS) or recent revascularization. A literature review of the influence of exercise, and PA and SB profiles in secondary prevention of CAD was performed using PubMed. All articles published between January 2001 and April 2019, meeting the inclusion criteria were considered. A total of 25 cross-sectional or prospective studies or randomized controlled trials (RCT) were included to this review. Exercise training was found to improve maximal oxygen consumption, QoL, and to reduce rehospitalizations and mortality among patients with established CAD. Remote PA interventions have not been as effective as the supervised exercise sessions in reducing the clinical endpoints. High SB, especially when combined to low PA, is associated with poor cardiorespiratory fitness and worse long-term prognosis among patients with ACS. In conclusion, exercise training and high PA are beneficial for patients with stable CAD, recent ACS or recent revascularization. High SB is associated with poor cardiopulmonary fitness and increased mortality in ACS patients. Novel tools using online applications and smart devices are promising means to offer remote guidance for PA among patients unable to participate in regular exercise sessions.

Negative pressure wound therapy in the treatment of deep sternal wound infections - a critical appraisal.

Introduction. Negative pressure wound therapy (NPWT) has widely become the first-line option in the treatment of deep sternal wound infections. After several positive reports in comparison with conventional treatment, very recent studies comparing NPWT with early reconstruction have favored the latter. Our aim was to evaluate the effectiveness and safety of NPWT in comparison with early flap reconstruction. Materials and methods. We concluded a retrospective analysis of 125 patients with deep sternal wound infection treated in a single institution between the years 2006 and 2018. NPWT became the first-line treatment in our hospital in 2011. The study group consisted of 55 patients treated primarily with NPWT with or without subsequent flap reconstruction. The control group consisted of 60 patients treated with flap reconstruction without prior NPWT. Ten patients with an immediate re-fixation and direct wound closure were excluded. Results. There were no significant differences between the two groups concerning the type or urgency of the original open-heart surgery, age, gender, or co-morbidities. In the NPWT group there was significantly higher mortality (p = .002), longer stay in the intensive care unit (p = .028), and in the university hospital (p < .001) as well as higher number of operations (p < .001). However, there were somewhat more surgical complications in the control group as well as a higher number of distant flap reconstructions. Overall, five patients suffered from NPWT associated bleeding. Conclusion. Our results raise concerns about the wide use of NPWT as a first-line treatment of deep sternal wound infections. Further evaluative studies are warranted to confirm the results.

Wrist Band Photoplethysmography Autocorrelation Analysis Enables Detection of Atrial Fibrillation Without Pulse Detection.

Atrial fibrillation is often asymptomatic and intermittent making its detection challenging. A photoplethysmography (PPG) provides a promising option for atrial fibrillation detection. However, the shapes of pulse waves vary in atrial fibrillation decreasing pulse and atrial fibrillation detection accuracy. This study evaluated ten robust photoplethysmography features for detection of atrial fibrillation. The study was a national multi-center clinical study in Finland and the data were combined from two broader research projects (NCT03721601, URL: https://clinicaltrials.gov/ct2/show/NCT03721601 and NCT03753139, URL: https://clinicaltrials.gov/ct2/show/NCT03753139). A photoplethysmography signal was recorded with a wrist band. Five pulse interval variability, four amplitude features and a novel autocorrelation-based morphology feature were calculated and evaluated independently as predictors of atrial fibrillation. A multivariate predictor model including only the most significant features was established. The models were 10-fold cross-validated. 359 patients were included in the study (atrial fibrillation n = 169, sinus rhythm n = 190). The autocorrelation univariate predictor model detected atrial fibrillation with the highest area under receiver operating characteristic curve (AUC) value of 0.982 (sensitivity 95.1%, specificity 93.7%). Autocorrelation was also the most significant individual feature (p < 0.00001) in the multivariate predictor model, detecting atrial fibrillation with AUC of 0.993 (sensitivity 96.4%, specificity 96.3%). Our results demonstrated that the autocorrelation independently detects atrial fibrillation reliably without the need of pulse detection. Combining pulse wave morphology-based features such as autocorrelation with information from pulse-interval variability it is possible to detect atrial fibrillation with high accuracy with a commercial wrist band. Photoplethysmography wrist bands accompanied with atrial fibrillation detection algorithms utilizing autocorrelation could provide a computationally very effective and reliable wearable monitoring method in screening of atrial fibrillation.

Necklace-embedded electrocardiogram for the detection and diagnosis of atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is the major cause of stroke since approximately 25% of all strokes are of cardioembolic-origin. The detection and diagnosis of AF are often challenging due to the asymptomatic and intermittent nature of AF. HYPOTHESIS: A wearable electrocardiogram (ECG)-device could increase the likelihood of AF detection. The aim of this study was to evaluate the feasibility and reliability of a novel, consumer-grade, single-lead ECG recording device (Necklace-ECG) for screening, identifying and diagnosing of AF both by a cardiologist and automated AF-detection algorithms. METHODS: A thirty-second ECG was recorded with the Necklace-ECG device from two positions; between the palms (palm) and between the palm and the chest (chest). Simultaneously registered 3-lead ECGs (Holter) served as a golden standard for the final rhythm diagnosis. Two cardiologists interpreted independently in a blinded fashion the Necklace-ECG recordings from 145 patients (66 AF and 79 sinus rhythm, SR). In addition, the Necklace-ECG recordings were analyzed with an automatic AF detection algorithm. RESULTS: Two cardiologists diagnosed the correct rhythm of the interpretable Necklace-ECG with a mean sensitivity of 97.2% and 99.1% (palm and chest, respectively) and specificity of 100% and 98.5%. The automatic arrhythmia algorithm detected the correct rhythm with a sensitivity of 94.7% and 98.3% (palm and chest) and specificity of 100% of the interpretable measurements. CONCLUSIONS: The novel Necklace-ECG device is able to detect AF with high sensitivity and specificity as evaluated both by cardiologists and an automated AF-detection algorithm. Thus, the wearable Necklace-ECG is a new, promising method for AF screening. CLINICAL TRIAL REGISTRATION: Study was registered in the ClinicalTrials.gov database (NCT03753139).

Continuous 24-h Photoplethysmogram Monitoring Enables Detection of Atrial Fibrillation.

Aim: Atrial fibrillation (AF) detection is challenging because it is often asymptomatic and paroxysmal. We evaluated continuous photoplethysmogram (PPG) for signal quality and detection of AF. Methods: PPGs were recorded using a wrist-band device in 173 patients (76 AF, 97 sinus rhythm, SR) for 24 h. Simultaneously recorded 3-lead ambulatory ECG served as control. The recordings were split into 10-, 20-, 30-, and 60-min time-frames. The sensitivity, specificity, and F1-score of AF detection were evaluated for each time-frame. AF alarms were generated to simulate continuous AF monitoring. Sensitivities, specificities, and positive predictive values (PPVs) of the alarms were evaluated. User experiences of PPG and ECG recordings were assessed. The study was registered in the Clinical Trials database (NCT03507335). Results: The quality of PPG signal was better during night-time than in daytime (67.3 ± 22.4% vs. 30.5 ± 19.4%, p < 0.001). The 30-min time-frame yielded the highest F1-score (0.9536), identifying AF correctly in 72/76 AF patients (sensitivity 94.7%), only 3/97 SR patients receiving a false AF diagnosis (specificity 96.9%). The sensitivity and PPV of the simulated AF alarms were 78.2 and 97.2% at night, and 49.3 and 97.0% during the daytime. 82% of patients were willing to use the device at home. Conclusion: PPG wrist-band provided reliable AF identification both during daytime and night-time. The PPG data's quality was better at night. The positive user experience suggests that wearable PPG devices could be feasible for continuous rhythm monitoring.

Preoperative atrial fibrillation in association with reduced haemoglobin predicts increased 30-d mortality after cardiac surgery.

OBJECTIVES: Atrial fibrillation is the most common arrhythmia occurring after cardiac surgery. Less attention has been focused on preoperative atrial fibrillation and anaemia as risk factors for mortality after cardiac surgery. The aim of this study was to determine preoperative risk factors for 30-d mortality after open-heart surgery. Design. The study population consisted of 2015 patients (73.4% men; mean age 68 years) undergoing coronary artery bypass grafting (CABG) (52.0%), aortic valve replacement (AVR) (18.6%), AVR and CABG (10.0%), mitral valve plasty or replacement (14.0%), and AVR and aortic root reconstruction (ARR) (5.5%) in Kuopio University Hospital from January 2013 to December 2016. Univariate and multivariate Cox proportional hazards models were used for statistical analyses. Kaplan-Meier survival curves were generated. Results. Total 30-d mortality was 1.8%. By Cox regression analysis, predictors of 30-d mortality (hazard ratio [HR] [95% confidence interval [CI]]) included female gender (1.95 [1.00-3.77]), preoperative atrial fibrillation, (2.38 [1.12-5.03]) reduced haemoglobin level (3.40 [1.47-7.90]), and pulmonary congestion (3.16 [1.52-6.55]). The combination of preoperative reduced haemoglobin and preoperative atrial fibrillation was a strong predictor (12.37 [4.40-34.77], p < .001). Estimated glomerular filtration rate (eGFR) predicted 30-d mortality in univariate models but was not an independent predictor in multivariate models. Conclusions. According to the main findings of our study, the combination of preoperative atrial fibrillation and reduced haemoglobin level substantially increase the risk of 30-d mortality after cardiac surgery. Identification of high-risk patients pre-operatively could help to make optimal clinical decisions for timing of operation and perioperative treatment.