Continuous Cardiac Monitoring Research Articles

Long-term rhythm monitoring with an implantable loop recorder in patients after the first clinical atrial fibrillation episode. Towards an individualized management.

Although atrial fibrillation (AF) is an arrhythmia with a variable clinical profile (symptomatic and asymptomatic episodes), the first symptomatic episode leads to its initial diagnosis in most cases. Nowadays, continuous and remote long-term cardiac rhythm monitoring is feasible by the use of implantable loop recorders. The data concerning the AF recurrences and progression after the first electrocardiographic-documented clinical AF episode demonstrates that a high percentage of patients may not suffer any other AF recurrence, or may present a low recurrence rate of the arrhythmia in the future. The AF burden may play a key role in the management of the arrhythmia as far as the decision-making for anticoagulation, rate and/or rhythm control therapy is concerned. There is evidence that a higher AF burden is associated with a higher risk of ischemic stroke. Non-vitamin K antagonists (NOACs) anticoagulants are increasingly used in the management of AF, providing a more predictable effect with rapid onset and offset of their action. The use of these agents in combination with devices that provide a continuous remote rhythm monitoring capability has encouraged anticoagulation strategies based on the AF burden. Data from tailored anticoagulation studies in AF are in favor of the long-term rhythm monitoring, ensuring a patient-centered approach with a better evaluation and more individualized management of AF, especially in patients with intermediate thromboembolic risk and high bleeding risk. Further large randomized trials are needed, not only to evaluate such strategies but also to elucidate the long-term cardiac rhythm monitoring in the AF management.

Abstract WP523: Aerobic Training Reduces Stroke Risk in Patients With Atrial Fibrillation

Introduction: Atrial fibrillation (AF) is the leading cause of fatal ischemic stroke. Although stroke risk factors can be identified using available clinical assessment tools, current standard of care primarily relies on antithrombotic/anticoagulation therapy and fails to proactively modify the underlying risk factors contributing to stroke. The purpose of this study was to determine the effect of moderate-to-high intensity aerobic training in alleviating stroke risk by reducing arterial stiffness and AF burden in AF patients. Methods: Forty-two patients with clinically diagnosed AF between the ages of 65-75 were recruited and randomly assigned to either a 3-month aerobic training with moderate to high intensity (i.e. >80%MHR, 45 minutes, 3-4 days/week) or a health education group. Vascular integrity was evaluated by carotid-radial pulse-wave-velocity (PWVcr), carotid intima-media-thickness (cIMT) and end-diastolic velocity (EDV); AF burden was quantified using a 2-week continuous cardiac event monitor (ZioXT patch, iRhythm); stroke risk was assessed using the CHA 2 DS 2 -VASc scale. All measurements were assessed before and after training. Results: Thirty AF patients participated in the aerobic training group (f=18, age=70±3) and 12 participated in the health education group (f=8, age=69±4). After 3 months, the aerobic training group exhibited significant improvement in PWVcr (12.6±3.2m/s vs. 9.6±2.1m/s, p=0.001), EDV (14.3±2.5cm/s vs. 15.9±2.1cm/s, p=0.01), AF burden (84.3±12.3% vs. 66.6±1.3%, p=0.01), and CHA 2 DS 2 -VASc score (2.2±1.3 vs. 0.9±0.9, p=0.05). In addition, the change of EDV is predictive of the stroke risk (r 2 =0.32, p=0.01). No significant change was observed in the health education group. Conclusion: We found that 3 months of supervised aerobic training at moderate-to-high intensity level appeared to improve vascular integrity, alleviate AF burden, and reduce stroke risk in patients with AF. More importantly, the AF burden and stroke risk are modulated by improvements in vascular functions. This finding warrants future large-scale investigations to examine the dose-response relationship of exercise reducing ischemic stroke risk.

Progress in noninvasive assessment of fluid responsiveness

Fluid infusion is one of the most common therapeutic measures in clinical practice. With the development of medical technology, the assessment of fluid responsiveness before fluid infusion has become simpler and less invasive. The assessment of fluid responsiveness is based on three aspects: cardiopulmonary interaction, volume-loading test and endogenous volume-loading test. This article reviews the progress in the assessment of fluid responsiveness with the application of ultrasound and noninvasive continuous cardiac output monitoring, and the prospect of future improvement. Key words: Noninvasive; Ultrasound; Continuous cardiac output monitoring; Fluid responsiveness

Efficacy of minimal invasive cardiac output and ScVO2 monitoring during controlled hypotension for double-jaw surgery

BackgroundControlled hypotension (CH) provides a better surgical environment and reduces operative time. However, there are some risks related to organ hypoperfusion. The EV1000/FloTrac system can provide continuous cardiac output monitoring without the insertion of pulmonary arterial catheter. The present study investigated the efficacy of this device in double jaw surgery under CH.MethodsWe retrospectively reviewed the medical records of patients who underwent double jaw surgery between 2010 and 2015. Patients were administered conventional general anesthesia with desflurane; CH was performed with remifentanil infusion and monitored with an invasive radial arterial pressure monitor or the EV1000/FloTrac system. We allocated the patients into two groups, namely an A-line group and an EV1000 group, according to the monitoring methods used, and the study variables were compared.ResultsEighty-five patients were reviewed. The A-line group reported a higher number of failed CH (P = 0.005). A significant correlation was found between preoperative hemoglobin and intraoperative packed red blood cell transfusion (r = 0.525; P < 0.001). In the EV1000 group, the mean arterial pressure (MAP) was significantly lower 2 h after CH (P = 0.014), and the cardiac index significantly decreased 1 h after CH (P = 0.001) and 2 h after CH (P = 0.007). Moreover, venous oxygen saturation (ScVO2) decreased significantly at both 1 h (P = 0.002) and 2 h after CH (P = 0.029); however, these values were within normal limits.ConclusionThe EV1000 group reported a lower failure rate of CH than the A-line group. However, EV1000/FloTrac monitoring did not present with any specific advantage over the conventional arterial line monitoring when CH was performed with the same protocol and same mean blood pressure. Preoperative anemia treatment will be helpful to decrease intraoperative transfusion. Furthermore, ScVO2 monitoring did not present with sufficient benefits over the risk and cost.

A Low-Cost System for Seismocardiography-Based Cardiac Triggering: A Practical Solution for Cardiovascular Magnetic Resonance Imaging at 3 Tesla

This study describes a pilot clinical validation of a new low-cost system for the continuous monitoring of the human body's cardiorespiratory activities within the magnetic resonance examination area. This study primarily focuses on monitoring cardiac activity and the related cardiac triggering. The patented system tested by the authors is based on seismocardiography (SCG). The study was conducted on 18 subjects on a Siemens Prisma 3T MR scanner. Standard anatomical and diffusion sequences were used to test cardiac activity monitoring. A wide range of commonly used diagnostic sequences were used to test imaging of the heart by means of cardiac triggering. System functionality was verified against a commercially available electrocardiography (ECG) system. Monitoring of cardiac activity (detection of the R-R interval in ECG and the AO-AO interval in SCG) was objectively evaluated by determining the overall probability of correct detection (ACC), sensitivity (SE), positive predictive value (PPV), and harmonic mean between SE and PPV, i.e. F1. Imaging quality control using Cardiac Triggering was performed by subjective evaluation of images by the physicians. The study conducted clearly confirmed the functionality of the system in terms of continuous cardiac activity monitoring. In all 18 subjects, a mean PPV > 99% was achieved; F1 > 99 %; SE > 99 %; ACC > 98 %; 1.96 sigma < 3.5 bpm. Also, Cardiac Triggering functionality was confirmed by the physicians on the basis of analyzing cardiac images using the T1/T2 balanced echo sequences and the T1 flash sequence measured natively.

LSTM-Based ECG Classification for Continuous Monitoring on Personal Wearable Devices.

A novel electrocardiogram (ECG) classification algorithm is proposed for continuous cardiac monitoring on wearable devices with limited processing capacity. The proposed solution employs a novel architecture consisting of wavelet transform and multiple long short-term memory (LSTM) recurrent neural networks (see Fig.1). Experimental evaluations show superior ECG classification performance compared to previous works. Measurements on different hardware platforms show the proposed algorithm meets timing requirements for continuous and real-time execution on wearable devices. In contrast to many compute-intensive deep-learning based approaches, the proposed algorithm is lightweight, and therefore, brings continuous monitoring with accurate LSTM-based ECG classification to wearable devices. The proposed algorithm is both accurate and lightweight. The source code is available online at http://lis.ee.sharif.edu.

Utilization of Continuous Cardiac Monitoring on Hospitalist-led Teaching Teams.

Guidelines for continuous cardiac monitoring (CCM) have focused almost exclusively on cardiac diagnoses, thus limiting their application to a general medical population. In this study, a retrospective chart review was performed to identify the reasons that general medical patients, cared for on hospitalist-led inpatient teaching teams between April 2017 and February 2018, were initiated and maintained on CCM, and to determine the incidence of clinically significant arrhythmias in this patient population. The three most common reasons for telemetry initiation were sepsis (24%), arrhythmias (12%), and hypoxia (10%). Most patients remained on telemetry for more than 48 hours (62%) and a significant number of patients were on telemetry until they were discharged from the hospital (39%). Of the cumulative total of more than 20,573 hours of CCM provided to this patient population, 37% of patients demonstrated only normal sinus rhythm and 3% had a clinically significant arrhythmia that affected management.

Atrial Fibrillation Detection Using a Novel Cardiac Ambulatory Monitor Based on Photo-Plethysmography at the Wrist.

BackgroundLong‐term continuous cardiac monitoring would aid in the early diagnosis and management of atrial fibrillation (AF). This study examined the accuracy of a novel approach for AF detection using photo‐plethysmography signals measured from a wrist‐based wearable device.Methods and Results ECG and contemporaneous pulse data were collected from 2 cohorts of AF patients: AF patients (n=20) undergoing electrical cardioversion (ECV) and AF patients (n=40) that were prescribed for 24 hours ECG Holter in outpatient settings (HOL). Photo‐plethysmography and acceleration data were collected at the wrist and processed to determine the inter‐pulse interval and discard inter‐pulse intervals in presence of motion artifacts. A Markov model was deployed to assess the probability of AF given irregular pattern in inter‐pulse interval sequences. The AF detection algorithm was evaluated against clinical rhythm annotations of AF based on ECG interpretation. Photo‐plethysmography recordings from apparently healthy volunteers (n=120) were used to establish the false positive AF detection rate of the algorithm. A total of 42 and 855 hours (AF: 21 and 323 hours) of photo‐plethysmography data were recorded in the ECV and HOL cohorts, respectively. AF was detected with >96% accuracy (ECV, sensitivity=97%; HOL, sensitivity=93%; both with specificity=100%). Because of motion artifacts, the algorithm did not provide AF classification for 44±16% of the monitoring period in the HOL group. In healthy controls, the algorithm demonstrated a <0.2% false positive AF detection rate.ConclusionsA novel AF detection algorithm using pulse data from a wrist‐wearable device can accurately discriminate rhythm irregularities caused by AF from normal rhythm.

Arrhythmic Burden as Determined by Ambulatory Continuous Cardiac Monitoring in Patients With New-Onset Persistent Left Bundle Branch Block Following Transcatheter Aortic Valve Replacement: The MARE Study

ObjectivesThe authors sought to determine: 1) the global arrhythmic burden; 2) the rate of arrhythmias leading to a treatment change; and 3) the incidence of high-degree atrioventricular block (HAVB) at 12-month follow-up in patients with new-onset persistent left bundle branch block (LBBB) following transcatheter aortic valve replacement (TAVR). BackgroundControversial data exist on the occurrence of significant arrhythmias in patients with LBBB post-TAVR. MethodsThis was a multicenter prospective study including 103 consecutive patients with new-onset persistent LBBB post-TAVR with the balloon-expandable SAPIEN XT/3 valve (n = 53), or the self-expanding CoreValve/Evolut R system (n = 50). An implantable cardiac monitor (Reveal XT, Reveal Linq) was implanted at 4 (3 to 6) days post-TAVR, and patients had continuous electrocardiogram monitoring for 12 months. All arrhythmic events were adjudicated in a central electrocardiography core lab. Primary endpoints were the incidence of arrhythmias leading to a treatment change, and the incidence of HAVB at 12-month follow-up. ResultsA total of 1,553 new arrhythmic events were detected in 44 patients (1,443 episodes of tachyarrhythmia in 26 patients [atrial fibrillation/flutter/atrial tachycardia: 1,427, ventricular tachycardia 16]; 110 episodes of bradyarrhythmia in 21 patients [HAVB 54, severe bradycardia 56]). All arrhythmic events were silent in 34 patients (77%), the arrhythmic event led to a treatment change in 19 patients (18%), and 11 patients (11%) required pacemaker or implantable cardioverter-defibrillator implantation (due to HAVB, severe bradycardia, or ventricular tachycardia episodes in 9, 1, and 1 patient, respectively). A total of 12 patients died at 1-year follow-up, 1 from sudden death. ConclusionsA high incidence of arrhythmic events was observed at 1-year follow-up in close to one-half of the patients with LBBB post-TAVR. Significant bradyarrhythmias occurred in one-fifth of the patients, and PPM was required in nearly one-half of them. These data support the use of a cardiac monitoring device for close follow-up and expediting the initiation of treatment in this challenging group of patients. (Ambulatory Electrocardiographic Monitoring for the Detection of High-Degree Atrio-Ventricular Block in Patients With New-onset PeRsistent LEft Bundle Branch Block After Transcatheter Aortic Valve Implantation [MARE study]: NCT02153307)

Elevated troponin and left bundle branch block in the setting of suspected septicemia and demand ischemia: to treat or not to treat.

Elevated troponin and atypical chest pain in the setting of septicemia and Type II Non ST elevation myocardial infarction is frequently encountered. These cases are not necessarily scheduled for emergent cardiac catheterization. High index of clinical suspicion and continuous in-patient cardiac monitoring with serial trending of cardiac enzymes are important in such cases. Subsequent sudden development of electrocardiogram changes requires prompt investigation with emergent coronary catheterization. These types of cases may be missed especially in females who present with atypical chest pain and in patients with Left bundle branch block.

Electrocardiographic RR Interval Dynamic Analysis to Identify Acute Stroke Patients at High Risk for Atrial Fibrillation Episodes During Stroke Unit Admission

Patients at short-term risk of paroxysmal atrial fibrillation (PAF) often exhibit increased RR interval variability during sinus rhythm. We studied if RR dynamic analysis, applied in the first hours after stroke unit (SU) admission, identified acute ischemic stroke patients at higher risk for subsequent PAF episodes detected within the SU hospitalization. Acute ischemic stroke patients underwent continuous cardiac monitoring (CCM) using standard bedside monitors immediately after SU admission. The CCM tracks from the first 48 h were analyzed using a telemedicine service (SRA clinic, Apoplex Medical, Germany). Based on the RR dynamics, the stroke risk analysis (SRA) algorithm stratified the risk for PAF as follows: low risk for PAF, high risk for PAF, presence of manifest AF. The subsequent presence/absence of PAF during the whole SU hospitalization was ruled out using all available CCMs, standard ECGs, or 24-h Holter ECGs. Two hundred patients (40% females, mean age 71 ± 16 years) were included. According to the initial SRA analysis, 111 patients (56%) were considered as low risk for PAF, 52 (26%) as high risk while 37 patients (18%) had manifest AF. A low-risk level SRA was associated with a reduced probability for subsequent PAF detection (1/111, 0.9%, 95% CI 0–4.3%) while a high-risk level SRA predicted an increased probability (20/52, 38.5% (95% CI 25–52%). RR dynamic analysis performed in the first hours after ischemic stroke may stratify patients into categories at low or high risk for forthcoming paroxysmal AF episodes detected within the SU hospitalization.

A Modified Mask for Continuous Cardiac Monitoring during Positive Airway Pressure Therapy.

A Positive Airway Pressure mask was modified to be able to measure the heart rate of the wearer during Positive Airway Pressure (PAP) therapy. The mask was modified by attaching sensors to measure Electrocardiography (ECG) and Photoplethysmography (PPG) signals, from which a heart rate was extracted. The ECG signal was recorded using stainless steel electrodes positioned on the wearer's head and neck. The PPG signal was measured from the wearer's forehead using a reflectance pulse oximeter attached to the mask. The modified device was tested on 19 healthy participants (mean age30.5 ± 9 years) in a simulated sleeping environment. For both the ECG and PPG signals, the device was able to correctly identify more than 95% of heartbeats for the majority of the participants. However, it was found that by combining the ECG and PPG heartbeat data, the percentage of heartbeats that could be detected was increased to 99%. The results showed that it may be possible to use this device to monitor sleep apnoea patients during PAP therapy in their homes.

Use Preferences for Continuous Cardiac and Respiratory Monitoring Systems in Hospitals: A Survey of Patients and Family Caregivers

The overarching objective of this research is to reduce the burden of 'alert fatigue' on patients and family caregivers who stay overnight in hospitals on units that provide continuous monitoring of cardiac and respiratory systems. When a patient develops respiratory compromise on the medical-surgical units of the hospital, the mortality rate is 29 times higher. Alarms require nurses to quickly respond, even when it is likely a false alarm. An anonymous survey was distributed to patients and family caregivers with 72 responses. Alarm sounds were judged most helpful to detect a high heart rate or unusual rhythm, and less helpful to detect a patient exiting from bed. The expectation was for an immediate response to an alarm, and that it would be annoying to have an alarm go off for hours. There was strong agreement with wanting alarm sounds to go to the nurse, but not be heard in the hospital room by patients or caregivers. Implications of these findings are discussed.

P007: Safety and effectiveness of a care protocol to treat migraine with Propofol in the emergency department

Introduction: An evidence-based care protocol to treat migraine with low-dose Propofol was implemented in May 2014 at the emergency department (ED) of the CHUL (Québec city). Given potential side effects of Propofol, we aimed to evaluate the safety and effectiveness of this protocol. Methods: We reviewed charts of all patients aged 16 years and older who received Propofol between May 2014 and August 2017 for a migraine headache with or without aura, as defined in the International Headache Society Classification. The care protocol consisted of: 1) administration of intra-venous Propofol 20 mg each 5 to 10 minutes as needed (maximum of 6 doses); 2) sets of vital signs before and after each dose; and 3) continuous cardiac and saturation monitoring. Our primary outcome measures were the incidence (95%CI) of the following side effects: low arterial pressure (&lt; 90 systolic or &lt; 65 mean), desaturation (SaO2&lt;92%), excessive sedation (scores 3 or 4 on the Pasero scale), and any arrhythmia. We also compared the mean reduction (95%CI) of pain pre- and post-treatment (visual analogous scale VAS 0-10) and the proportion (95%CI) of rescue medication among patients who received Propofol as first-line medication to a matched cohort of patients who had Metoclopramide first. The two cohorts were paired for gender, age, triage priority, and month/year of ED visit. Results: Over the 3-year study period, 45 patients with migraine received Propofol through the care protocol, either as a first-line or a rescue therapy. In this cohort, hypotension, bradycardia (&lt;60/min) and desaturation occurred in 17.8% (8.0-32.1), 13.3% (5.1-26.8) and 6.7% (1.4-18.3) of cases respectively; no excessive sedation was reported. An intervention was undertaken in 4 cases [8.9% (2.5-21.2) 3 iv fluid bolus, 1 supplemental oxygen] to palliate the side effects of Propofol. A statistically significant mean reduction of 3.6 points (2.8-4.4) on the VAS scale was observed in patients treated with Propofol as first-line therapy (n=35). However, patients managed with first-line Metoclopramide (n=100) experienced a significantly higher mean reduction of their VAS score [5.3 (4.6-6.0)] than the Propofol group (p=0.003). The proportion of patients requiring the use of rescue medication was higher among patients first treated with Propofol [77.1% (63.2-91.1) vs. 29.0% (20.1-37.9); p&lt;0.001]. Conclusion: Our care protocol to treat migraine with low doses of Propofol appears to be safe and to cause very few side effects prompting corrective interventions. Continuous (as opposed to intermittent) heart and saturation monitoring is probably not indicated. Given the effectiveness of Propofol compared to Metoclopramide, our care protocol will be used as a second-line therapy.

Recurrence rate of atrial fibrillation after the first clinical episode: A prospective evaluation using continuous cardiac rhythm monitoring.

Decision making regarding a patient who has experienced a first clinical episode of atrial fibrillation (AF) is challenging, and the AF recurrences should be a significant consideration. Continuous long-term rhythm monitoring via implantable loop recorders (ILRs) has enabled us to evaluate the AF recurrence profile after the first clinical episode and to investigate clinical parameters associated with the course of the arrhythmia. Continuous rhythm monitoring via ILRs in AF patients after the first clinical episode is of clinical significance and precisely evaluate the AF recurrence profile. Thirty consecutive patients with paroxysmal AF received an ILR after their first symptomatic episode. We evaluated the maximum duration of episodes and the recurrence rate of the arrhythmia during a follow-up period of 3 years. Three patients (10%) had no AF recurrence, whereas 4 patients (13.3%) presented only 1 episode. Almost half of the patients (46.7%) had a low recurrence rate (<5 episodes/year), whereas the majority of patients (19/30) suffered from episodes with maximum duration ≤24 hours. Eleven patients (36.7%) presented either no episode or a low recurrence rate with episodes lasting ≤24 hours. The use of statins was greater in patients with a low recurrence rate (P = 0.025). A significant percentage of patients either suffer no AF recurrence after their first symptomatic episode or show a low recurrence rate. Most patients present episodes of short duration. If these findings are confirmed in larger studies, they could have clinical implications ensuring individualized management of the arrhythmia in the future.

Comparison of dexmedetomidine versus propofol on hemodynamics in surgical critically ill patients

BackgroundSedation with dexmedetomidine and propofol may cause hypotension or bradycardia. This study aimed to compare the effects of dexmedetomidine and propofol on hemodynamics and clinical outcomes in surgical intensive care unit (ICU) patients after major abdominal surgery. Materials and methodsEnrolled patients were randomly allocated to the dexmedetomidine or propofol group. Cardiac index was measured using a continuous noninvasive cardiac output monitor on the basis of chest bioreactance. Heart rate, blood pressure, opioid requirement, urine output, delirium incidence, ICU length of stay, and total hospital length of stay were compared between the two groups. The incidences of bradycardia, hypotension, and severe low cardiac index were compared. ResultsWe enrolled 60 patients. Heart rate and mean arterial pressure were significantly lower in the dexmedetomidine group than in the propofol group. Cardiac index did not differ significantly between the two groups (dexmedetomidine group 3.1 L/min/m2, [95% confidence interval {95% CI} 2.8-3.3] versus propofol group 3.2 L/min/m2 [95% CI 2.9-3.5], P = 0.578). The incidences of bradycardia, hypotension, and severe low cardiac index did not differ significantly between the two groups. ConclusionsCardiac index did not differ significantly between the dexmedetomidine and propofol groups in surgical ICU patients after major abdominal surgery.

Prophylactic pulmonary vein isolation during isthmus ablation for atrial flutter: Three-year outcomes of the PREVENT AF I study.

The PREVENT AF I study demonstrated that prophylactic pulmonary vein isolation (PVI) in patients with pure typical atrial flutter (AFL) resulted in substantial reduction of new-onset atrial fibrillation (AF) during 1-year follow-up as assessed by continuous implantable cardiac monitor (ICM). The objective of this study was to assess 3-year outcomes. Fifty patients with documented AFL were randomized to either cavotricuspid isthmus (CTI) ablation alone (n=25) or CTI with concomitant PVI (n=25). The primary endpoint of the study was the occurrence of any atrial tachyarrhythmia with the monthly burden exceeding 0.5% on the ICM. At the end of 3 years, freedom from any atrial tachyarrhythmia was 48% (95% confidence interval [CI]: 32-72%) in the CTI plus PVI group as compared to 20% (95% CI: 9-44%) in the CTI-only group (P=0.01). Freedom from redo procedures was also higher: 92% (95% CI: 82-100%) versus 68% (95% CI: 52-89%), respectively (P=0.027). The 3-year AF burden favored the combined ablation group: 6.2%versus 16.8% (P=0.03). In the CTI-only group, 12 (48%) patients were hospitalized compared to 4 (16%) in the PVI + CTI group (P=0.03). Two patients in the CTI-only group developed stroke with no serious adverse events in the PVI + CTI group. Prophylactic PVI in patients with only typical AFL resulted in a significant reduction of new-onset AF and burden during long-term follow-up as assessed by ICM, with consequent reduction in hospitalizations and need to perform repeat ablation for AF.

Issues of Immunological and Hemodynamic Monitoring Before and During Kidney Transplantation in Sensitized Heart Transplant Recipient

Previously transplanted highly sensitized patients experience problems with subsequent transplantation. It is also difficult to provide optimal hemodynamic conditions during successive kidney transplantation in heart transplant recipients. Patient and methodsWe present a case of a 56-year old patient with end-stage renal failure after heart transplantation performed 21 years ago and hemodialyzed using arteriovenous fistula. The patient had 69% panel-reactive antibodies, had been on the active waiting list since 2013, and presented 335 positive crossmatches with deceased donors. He also positively crossmatched with a potential living donor. Detailed examination of anti-HLA antibodies revealed the absence of IgG donor-specific antibodies and negative crossmatch with dithiothreitol-treated serum. The transplantation from his wife was performed with positive crossmatch after 4 plasma exchanges and thymoglobulin induction. Because sympathetic and parasympathetic denervation of the transplanted heart and the presence of arteriovenous fistula induced volume overload of the right heart, we used central venous pressure (CVP) and the PiCCO2 for postsurgical assessment of cardiac output. ResultsMonitoring, like CVP and other static exponents of preload obtained by PICCO (extravascular lung water, global end-diastolic volume index) as well as the dynamic parameters obtained by PiCCO2 (pulse pressure variation, stroke volume variation), was not sensitive enough to describe recipient volume status. The immediate graft function was observed, and after 11 months satisfactory estimated glomerular filtration rate is noted with the absence of donor-specific antibodies. ConclusionThe history of heart transplantation with existing arteriovenous fistula makes clinical tools such as continuous cardiac output monitoring and CVP parameter inadequate for describing the hemodynamic situation. The high level of panel-reactive antibodies and positive crossmatch possibly caused by IgM antibodies do not have to withdraw the recipient from kidney transplantation.

Prediction of new-onset atrial fibrillation after first-ever ischemic stroke: A comparison of CHADS2, CHA2DS2-VASc and HATCH scores and the added value of stroke severity

Background and aimsEarly detection of atrial fibrillation after stroke is important for secondary prevention in stroke patients without known atrial fibrillation (AF). We aimed to compare the performance of CHADS2, CHA2DS2-VASc and HATCH scores in predicting AF detected after stroke (AFDAS) and to test whether adding stroke severity to the risk scores improves predictive performance. MethodsAdult patients with first ischemic stroke event but without a prior history of AF were retrieved from a nationwide population-based database. We compared C-statistics of CHADS2, CHA2DS2-VASc and HATCH scores for predicting the occurrence of AFDAS during stroke admission (cohort I) and during follow-up after hospital discharge (cohort II). The added value of stroke severity to prediction models was evaluated using C-statistics, net reclassification improvement, and integrated discrimination improvement. ResultsCohort I comprised 13,878 patients and cohort II comprised 12,567 patients. Among them, 806 (5.8%) and 657 (5.2%) were diagnosed with AF, respectively. The CHADS2 score had the lowest C-statistics (0.558 in cohort I and 0.597 in cohort II), whereas the CHA2DS2-VASc score had comparable C-statistics (0.603 and 0.644) to the HATCH score (0.612 and 0.653) in predicting AFDAS. Adding stroke severity to each of the three risk scores significantly increased the model performance. ConclusionsIn stroke patients without known AF, all three risk scores predicted AFDAS during admission and follow-up, but with suboptimal discrimination. Adding stroke severity improved their predictive abilities. These risk scores, when combined with stroke severity, may help prioritize patients for continuous cardiac monitoring in daily practice.

Responsiveness of Noninvasive Continuous Cardiac Output Monitoring During the Valsalva Maneuver.

To describe the baseline hemodynamic variables and response time of hemodynamic changes associated with the Valsalva maneuver using noninvasive continuous cardiac output monitoring (Nexfin). Hemodynamic monitoring provides an integral component of advanced clinical care and the ability to monitor response to treatment interventions. The emergence of noninvasive hemodynamic monitoring provides clinicians with an opportunity to monitor and assess patients rapidly with ease of implementation. However, the responsiveness of this method in tracking dynamic changes that occur has not been fully elucidated. A prospective observational study was conducted involving 44 healthy volunteers (age = 38 ±12 years). Participants performed a Valsalva maneuvers to illicit dynamic changes in blood pressure, cardiac output, cardiac index, systemic vascular resistance index (SVRI), and stroke volume. Changes in these hemodynamic parameters were monitored while performing repeated standardized Valsalva maneuvers. Baseline hemodynamic values were obtained in all 44 participants, and showed an interaction with age, accompanying a significant decline in cardiac index (r = -.66, p < .05) and stroke volume (r = -.68,p < .05), and an increase in SVRI (r = .67, p < .05) with increasing age. The Valsalva maneuver, performed in 20 participants, resulted in a change of 10% from baseline blood pressure and cardiac index, which was detected within 4.53 s (SD = 4.36) and 3.31 s (SD = 2.21), respectively. Noninvasive continuous cardiac monitoring demonstrated the ability to rapidly detect logical and predictable hemodynamic changes. These observations suggest that such Nexfin technology may have useful clinical applications.