Direct Current Pulse Atmospheric Pressure Plasma Jet Treatment on Electrochemically Deposited NiFe/Carbon Paper and Its Potential Application in an Anion-Exchange Membrane Water Electrolyzer.

An atmospheric pressure plasma jet (APPJ) is used to process electrochemically deposited NiFe on carbon paper (NiFe/CP). The reactive oxygen and nitrogen species (RONs) of the APPJ modify the surface properties, chemical bonding types, and oxidation states of the material at the self-sustained temperature of the APPJ. The APPJ treatment further enhances the hydrophilicity and creates a higher disorder level in the carbon material. Moreover, the metal carbide bonds of NiFe/CP formed in the electrochemical deposition (ED) process are converted to metal oxide bonds after APPJ processing. The potential application of APPJ treatment on NiFe/CP in alkaline water electrolysis is demonstrated. With more oxygen-containing species and better hydrophilicity after APPJ treatment, APPJ-treated NiFe/CP is applied as the electrocatalyst for the oxygen evolution reaction (OER) in alkaline water electrolysis. APPJ-treated NiFe/CP is also used in a custom-made anion-exchange membrane water electrolyzer (AEMWE); this should contribute toward realizing the practical large-scale application of AEM for hydrogen production.

NiFe2O4 Material on Carbon Paper as an Electrocatalyst for Alkaline Water Electrolysis Module.

NiFe2O4 material is grown on carbon paper (CP) with the hydrothermal method for use as electrocatalysts in an alkaline electrolyzer. NiFe2O4 material is used as the anode and cathode catalysts (named NiFe(+)/NiFe(-) hereafter). The results are compared with those obtained using CP/NiFe as the anode and CP/Ru as the cathode (named NiFe)(+)/Ru(-) hereafter). During cell operation with NiFe(+)/Ru(-), the current density reaches 500 mA/cm2 at a cell voltage of 1.79 V, with a specific energy consumption of 4.9 kWh/m3 and an energy efficiency of 66.2%. In comparison, for NiFe(+)/NiFe(-), the current density reaches 500 mA/cm2 at a cell voltage of 2.23 V, with a specific energy consumption of 5.7 kWh/m3 and an energy efficiency of 56.6%. The Faradaic efficiency is 96-99%. With the current density fixed at 400 mA/cm2, after performing a test for 150 h, the cell voltage with NiFe(+)/Ru(-) increases by 0.167 V, whereas that with NiFe(+)/NiFe(-) decreases by only 0.010 V. Good, long-term stability is demonstrated.

Gap between guidelines and clinical practice in heart failure with reduced ejection fraction: Results from TSOC-HFrEF registry.

BACKGROUND: Heart failure (HF) is a global health problem. Guidelines for the management of HF have been established in Western countries and in Taiwan. However, data from the Taiwan Society of Cardiology-Heart Failure with reduced Ejection Fraction (TSOC-HFrEF) registry showed suboptimal prescription of guideline-recommended medications. We aimed to analyze the reason of non-prescription and clinical outcomes as a result of under-prescription of medications. METHODS: A total of 1509 patients hospitalized for acute HFrEF were recruited in 21 hospitals in Taiwan by the end of October 2014. Prescribed guideline-recommended medications and other relevant clinical parameters were collected and analyzed at discharge and 1 year after index hospitalization. RESULTS: At discharge, 62% of patients were prescribed with either angiotensin-converting enzyme-inhibitors (ACEI) or angiotensin receptor blockers (ARB); 60% were prescribed with beta-blockers and 49% were prescribed with mineralocorticoid receptor antagonists (MRA). The proportions of patients at ≥50% of the target dose for ACEI/ARB, beta-blockers and MRA were 24.4%, 20.6%, 86.2%, respectively. At 1-year follow-up, dosages of ACEI/ARB and MRA were up-titrated in about one-fourth patients, and dosages of beta-blocker were up-titrated in about 40% patients. One-year mortality rate was lowest in patients who received at least 2 classes of guideline-recommended medications with ≥50% of the target dose, and highest in those who received 0 or 1 class of medications. CONCLUSION: The TSOC-HFrEF registry demonstrated the under-prescription of guideline-recommended medications and reluctance of physicians to up-titrate medications to target dose. Action plan needs be formulated in order to improve physician's adherence to HF guidelines.

Application of the Transtheoretical Model to Exercise Behavior and Physical Activity in Patients after Open Heart Surgery.

PURPOSE: To assess exercise behavior and physical activity levels after open heart surgery. METHODS: This prospective cohort study included 130 patients (70.8% male, aged 61.0 ± 12.2 years, 53.8% coronary bypass grafting) who underwent open heart surgery. The exercise behavior and physical activity of these patients were assessed at the 3- and 6-month follow-up appointments. Additional interviews were also conducted to further assess exercise behavior. Physical activity duration and metabolic equivalents were calculated from self-reported questionnaire responses. Moreover, possible related demographic factors, clinical features, participation in cardiac rehabilitation programs, and physical activity levels were additionally evaluated. RESULTS: Six months after hospital discharge, most patients were in the action (39.2%) and maintenance (37.7%) stages. Other subjects were in the precontemplation (11.5%), contemplation (5.4%), and preparation (6.2%) stages. The average physical activity level was 332.6 ± 377.1 min/week and 1198.1 ± 1396.9 KJ/week. Subjects in the action and maintenance stages exercised an average of 399.4 ± 397.6 min/week, significantly longer than those in other stages (116.2 ± 176.2 min/week, p = 0.02). Subjects that participated in outpatient cardiac rehabilitation programs after discharge may have the better exercise habit. Gender had no significant effect on exercise behavior 6 months after hospital discharge. CONCLUSIONS: Most subjects following open heart surgery may maintain regular exercise behavior at 6 months after hospital discharge. Physical activity levels sufficient for cardiac health were achieved by subjects in the active and maintenance stages. Outpatient cardiac rehabilitation programs are valuable for encouraging exercise behavior after heart surgery. KEY WORDS: Exercise behavior; Open heart surgery; Physical activity; Transtheoretical model.

Intraoperative three-dimensional transesophageal echocardiography for assessing the defect geometries of mitral prosthetic paravalvular leak during transcatheter closure.

BACKGROUND: Paravalvular leaks (PVLs) are a common complication of prosthetic valve replacement. Use of the transcatheter intervention technique is a suitable alternative in high-risk patients who may not tolerate repeat surgery. Common reasons for failure of this demanding intervention include poor imaging quality and unsuitable anatomy. The purpose of this study was to assess the usefulness and the incremental value of real-time three-dimensional (RT 3D) transesophageal echocardiography (TEE) over two-dimensional (2D) TEE findings in the evaluation of the geometry and track of mitral PVLs during transcatheter closure. METHODS: Five patients with six mitral PVLs at high risk for repeat surgery underwent transcatheter leak closure. Intraoperative RT 3DTEE was used to assess the location, shape, number, and size of the defects. Transapical approaches were used in all cases with fluoroscopic and RT 3D TEE guidance of the wire and catheter, device positioning, and assessment of residual leak after the procedure. RESULTS: In all of the cases, defects with irregular crescent shapes and distorted tracks were clearly delineated by RT 3D TEE. This was compared to those results obtained through 2D TEE, which was unable to characterize the defects. Three cases showed small leaks, which were completely occluded with a patent ductus arteriosus (PDA) device in two cases, and a muscular ventricular septal defect (mVSD) occluder combined with coil devices in one case. One case involved a large leak and early device embolization of the muscular VSD occluder, which was removed surgically, and demonstrated a crescent-shaped defect. One patient had two releaks 2 months subsequent to the procedure due to two new extended leaks at the tails of the crescent-shaped defect. CONCLUSION: RT 3D TEE can clearly delineate the geometries of defects in their entirety, including shape, size, and location of the defect and track canal. It would also appear that RT 3D TEE is superior to 2D TEE in the process of guiding the wire through the difficult canal anatomy, facilitating the overall procedure. The small mitral PVLs can be completely occluded, but subsequent complications occurred with large defect closures because of embolization or releak. Therefore, transcatheter closure of PVLs seems to be an attractive alternative for these patients, but newer occluder designs that better conform to leak geometry will be required to improve outcomes.

The additional value of live/real-time three-dimensional transesophageal echocardiography over two-dimensional transesophageal echocardiography for assessing mitral regurgitation with eccentric jets.

BACKGROUND: Two-dimensional transesophageal echocardiography (2D TEE) Doppler color flow imaging is the gold standard for assessing the severity of mitral regurgitation (MR). Severe MR with very eccentric jet may involve more than one mitral leaflet lesion and can be missed by 2D TEE. The purpose of this study was to assess the usefulness and the incremental value of real-time three-dimensional (RT 3D) TEE over 2D TEE findings in the evaluation of patients suffering eccentric MR with more than one mitral leaflet lesion. METHODS: Intraoperative 2D TEE and RT 3D TEE examinations were performed on 168 patients with Carpenter II MR who underwent surgery. MR was defined as either central, free-standing eccentric jet or very eccentric jet. 2D TEE and RT 3D TEE finding were compared with surgical findings. RESULTS: Of these 168 MR patients, 25 patients (14.9%) had central jets and 143 patients (85.1%) had eccentric jets. Among 143 patients with eccentric jets, 47 patients (32.9%) had free-standing eccentric MR jets, and 96 (67.1%) patients had very eccentric jets. 3D TEE diagnosed the severity and location of MR lesions correctly in all patients; this was not the case with 2D TEE, which had significant diagnostic misses in nine patients (9.4%, p < 0.001) having MR with very eccentric jets. These nine patients had lesions on both mitral leaflets, which were missed during 2D TEE examination owing to the highly turbulent flows produced by very eccentric jets from one mitral leaflet lesion and impinging the opposite mitral leaflet lesion. CONCLUSION: The severity of MR with very eccentric jet was more accurately and comprehensively assessed by 3D TEE than by 2D TEE. Therefore, intraoperative RT 3D TEE provides incremental information that is generally superior to 2D TEE in patients with complex MR due to very eccentric jets.

The utilization of twelve-lead electrocardiography for predicting sudden cardiac death after heart transplantation.

BACKGROUND: Sudden cardiac death (SCD) occurs commonly after heart transplantation (HTX). The utilization of surface electrocardiography (ECG) to assess post-HTX SCD has not been investigated thoroughly. This study aimed to investigate the specific changes in surface ECG in HTX patients with SCD. METHODS: A total of 227 HTX patients (age 48 ± 14 y/o, mean donor age 34 ± 14 y/o, 173 males) were followed up regularly at the outpatient clinic. Twelve-lead ECG's were recorded during 1-2 monthly visits. Serial ECG parameters and relevant clinical data were collected and analyzed. RESULTS: During the follow-up period of 96 ± 51 months, SCD occurred in 28 (12.3%) patients. The baseline ECG parameters were comparable between patients with and without SCD. Important ECG trends of rising rest heart rates and prolongation of corrected QT (QTc) and JT (JTc) intervals were observed prior to development of SCD. After adjustment for other clinical variables, the independent predictors for SCD were older donor age (p = 0.014, OR 1.05, 95% CI 1.01-1.09), faster heart rate (p = 0.006, OR 1.06, 95% CI 1.02-1.1) and longer JTc interval (p = 0.015, OR 1.03, 95% CI 1.01-1.06). SCD occurred in 71.4% patients presenting with all three risk predictors. CONCLUSIONS: Besides older donor age, important ECG signs, including prolongation of the JTc interval and increased heart rate during post HTX follow up, could predict SCD.

Midterm results of vascular ring connector in open surgery for aortic dissection.

OBJECTIVES: This study observed midterm results of vascular ring connectors in surgery for aortic dissection. METHODS: Vascular ring connectors were used as stents in vascular grafts to achieve quick, sutureless anastomoses. Tapes were used to secure ringed vascular grafts from outside the aorta. RESULTS: From November 2007 to February 2011, 113 consecutive patients with aortic dissection, except 3 in preoperative profound shock, underwent open surgery. All underwent aortic reconstruction with vascular grafts and vascular ring connectors: ascending aorta in 29, descending thoracic aorta in 20, distal hemiarch plus descending thoracic aorta in 22, total arch in 14, ascending aorta plus total arch in 12, total arch plus descending thoracic aorta in 7, ascending aorta plus arch plus descending thoracic aorta in 8, and thoracoabdominal aorta in 1. Concomitant operations were 19 Bentall procedures, 14 coronary bypasses, 2 mitral valve replacements, 1 aortic valve replacement, and 1 heart transplant. We used sternotomy to repair 77% of type B dissections, 83% with elephant trunks. Time to extubation was 9.0 ± 6.2 hours. Average blood loss was 345 ± 195 mL. Half the patients needed no blood transfusion. In-hospital mortality was 5.3%; late mortality was 2.7%. CONCLUSIONS: Use of vascular ring connectors in surgical repair for aortic dissection might reduce risks and improve early and midterm results. With addition of elephant trunk, most type B dissections could be repaired through sternotomy. With the improved surgical results, we can suggest open repair for most uncomplicated type B dissections; however, more long-term follow-up is needed.

The ability of live three-dimensional transesophageal echocardiography to evaluate the attachment site of intracardiac tumors.

In this study, a case of a right ventricular myxoma and a case of a right ventricular hemangioma are used to demonstrate the ability of live three-dimensional transesophageal echocardiography (3DTEE) to assess the site of tumor attachment. Because 3DTEE has the ability to visualize desired structures in multiple planes, we defined the attached portion of the tumors and measured the en face view dimensions. In addition, the improved ability of 3DTEE to evaluate tissue characteristics allowed differentiation of the heterogeneous myxoma and highly vascular hemangioma. On the contrary, because two-dimensional (2D) TEE only allows structures to be viewed in a 2D plane, the attachment site can be located but complete delineation and measurement of area is not possible. As surgical options become less invasive, accurate attachment site location and size will become more important to ensure complete excision.

Successful transcatheter closure of a residual patent ductus arteriosus with complex anatomy after surgical ligation using an amplatzer ductal occluder guided by live three-dimensional transesophageal echocardiography.

Residual patent ductus arteriosus (PDA) after surgical ligation is not common, but the anatomy of the residual duct may be distorted by the surgical ligation resulting in a difficult transcatheter closure. Such distorted anatomy of the duct may not be demonstrated by the two-dimensional transesophageal echocardiography (2D TEE). Fortunately, live 3D TEE provided the precise anatomy of the elongated distorted residual duct, and as in the case presented herein, guided the Amplatzer ductal occluder (ADO). We concluded that live 3D TEE provided novel images of complex residual ducts and successful guidance of a ductal occluder.

A new vascular ring connector in surgery for aortic dissection.

OBJECTIVE: To improve the surgical results of aortic dissection, we used a novel vascular ring connector for anastomosis. METHODS: The vascular ring connector is a titanic ring used as a stent in the vascular graft to achieve a quick, blood-sealed, and sutureless anastomosis. From November 2007 to December 2008, 19 consecutive patients (age range 36-77 years; 16 male and 3 female) with aortic dissection underwent open surgery. All patients received aortic reconstruction with vascular grafts (including 5 cases of arch replacement). The combined procedures were 5 Bentall and 4 coronary artery bypass graft operations. RESULTS: There were no significant blood leaks from the anastomotic sites. The time required for each anastomosis was 1 to 2 minutes. All patients were discharged uneventfully and are still doing well after a follow-up period of 1 to 12 months. CONCLUSION: The vascular ring connector may improve the early surgical results of aortic dissection by reducing both the time for anastomosis and the risk of bleeding and may be an alternative technique for aortic reconstruction. Its usefulness in the routine treatment of aortic dissection warrants further evaluation.

High-output heart failure resulting from an obscure traumatic arteriovenous fistula.

Traumatic arteriovenous fistula (AVF) is not an uncommon disorder, but late discovery and the presentation of high-output heart failure is very rare. This patient did not know that he had traumatic AVF after a gunshot injury in the left thigh 14 years ago. The major presentation of the AVF was signs of heart failure. We performed surgical repair after making the diagnosis. The patient recovered with an uneventful course. This report stresses the importance of history-taking and physical examination in making the diagnosis of traumatic AVF.

Long-term survival and prognostic implications after coronary artery bypass grafting in Chinese patients with coronary artery disease.

OBJECTIVES: This hospital-based study was conducted to determine the survival rates of patients after coronary artery bypass grafting (CABG) surgery and the associated prognostic factors related to all-cause mortality during a 7-year follow-up in Taiwan. METHODS AND RESULTS: Between January 1997 and December 2003, the medical records of 1877 patients who underwent primary, isolated CABG surgery were studied. The Kaplan-Meier method was used to estimate survival. Multiple Cox regression was used to investigate the independence of prognostic factors associated with all-cause mortality. Of the 1877 patients who underwent CABG surgery, 192 expired during the 7-year study period. The overall patient survival rate was 85.96% (95% CI: 83.74-88.16). Using multiple Cox regression analysis, in addition to female gender, older age at surgery, pulmonary oedema, longer ischaemic time, longer cardiopulmonary bypass time, and poorer postoperative left ventricular ejection fraction were significant factors associated with all-cause mortality for both men and women. Associated prognostic factors varied by gender. For men, smoking (RR = 2.82, 95% CI: 1.06-4.16), respiratory failure (RR = 6.88, 95% CI: 3.29-14.40) and cardiogenic shock (RR = 4.04, 95% CI: 2.13-7.67) were significantly related to all-cause mortality, but not for women. Sepsis (RR = 8.97,95% CI: 1.19-19.81) and ICU stay (RR = 1.03,95% CI: 1.01-1.05) were significantly related to all-cause mortality among female patients only. CONCLUSIONS: Several gender-related differences were noted pertaining to all-cause mortality and the relationships between smoking, sepsis, respiratory failure, cardiogenic shock, and ICU stay.

Cardiopulmonary resuscitation in prone position: a simplified method for outpatients.

BACKGROUND: The efficacy of cardiopulmonary resuscitation (CPR) is vital for saving lives of victims with sudden cardiac arrest. In 1960, Kuowenhoven and colleagues proposed the method that has become standard for CPR. Despite vast input of resources for public education and training of this procedure, its success rate outside hospitals remains poor to dismal. During CPR, restoration of respiration is as important as circulation. But opening the airway and giving effective mouth-to-mouth respiration is difficult for lay people to learn. Furthermore, most bystanders are reluctant to do mouth-to-mouth respiration because of the risk of infection. Therefore, the general population needs a more simplified CPR method for outpatients. The practice of CPR in the prone position, first proposed by McNeil in 1989, has not been adopted, despite the fact that it meets the desirable requirements of ideal resuscitation: simultaneous restoration of circulation and respiration with a very simple maneuver. METHODS: Part 1 (circulation test): Eleven patients who expired in the intensive care unit (ICU), with arterial lines attached, received standard pre-cordial cardiac massage, and the generated blood pressure (BP) was recorded. They were then turned to the prone position, with the head turned to one side. We compressed the patient's thoracic spine with the same force used in standard CPR (rhythm of approximately 60 per minute each time when the back bounces back), and the BP was also recorded. Part 2 (ventilation test): Ten healthy volunteers (5 doctors and 5 nurses) were enlisted for respiratory assessment during compression on the back. With the nose clipped and spontaneous breathing held, the volunteer's exhaled tidal volume upon compression was measured with a spirometer. RESULTS: Standard external cardiac massage of the cadavers generated BPs of 55 +/- 20/13 +/- 7 mmHg; however, external compression on the back of the cadavers generated higher BP of 79 +/- 20/17 +/- 10 mmHg (p = 0.028, Wilcoxon signed-rank analysis). External compression on the back of the volunteers generated mean tidal volumes of 399 +/- 110 mL. CONCLUSION: Our study revealed that prone CPR provides good respiratory and circulatory support at the same time. It is easy to perform and it may be a good alternative way for bystanders to perform CPR in public surroundings. We recommend that more investigators do further studies on this topic.

Development of an echocardiographic method for choosing the best fitting single-pass VDD lead.

To achieve stable single-lead VDD pacing, a selection of the electrode with the optimal distance between the lead tip and the floating atrial dipole (AV distance [AVD]) is important. The authors hypothesized that the size of the right heart chambers may affect atrial sensing, and that measurement of their internal dimension at end-diastole (RHIDd) in the apical four chamber view by transthoracic echocardiography may aid in choosing the proper AVD. Twenty-six consecutive cases that had undergone VDD pacer implantation using the conventional chest X ray were examined retrospectively by the echocardiographic method. The chest x-ray method properly selected a lead with optimal atrial sensing, defined as minimum P wave amplitude > or = 1.0 mV, for only 20 (77%) of 26 patients. By comparing these results with their respective RHIDd, a cut-off point of 13 cm was obtained that indicated a criterion for choosing the proper AVD. The indication was that if the RHIDd was > or = 13 cm, a lead with an AVD of 15.5/16 cm should have been used; if the RHIDd was < 13 cm, a lead with an AVD of 13/13.5 cm should have been chosen. Using the echocardiographic method, all six patients who had suboptimal atrial sensing could be identified and classified as having missized (four undersized; two oversized) permanent leads. In conclusion, the described method provides a promising preoperative assessment of the best fitting electrode length in single lead VDD pacing. A prospective study is ongoing to verify its applicability.