Experience using multielectrode cardiac catheters for detection of electrophysiologic activity of the human urinary bladder.

AIM: To determine the feasibility of commercially available multielectrode cardiac electrophysiology catheters to detect electrical activity in the human bladder. METHODS: Ten subjects requiring cystoscopy for the evaluation of lower urinary tract pathology were eligible for participation in our study. After routine rigid cystoscopy with a 70° cystoscope, various multielectrode cardiac electrophysiology catheters were introduced into the bladder. One of three catheters with different electrode configurations was used per subject. Electroanatomical images of the bladder were created and spontaneous electrical activity was recorded. Subjective response to electrical stimuli delivered across the electrodes (20 mA at 5 ms pulse width, rate 100 ms) was also recorded. The responses were qualitatively compared with that from a prior study. RESULTS: Electrical activity recorded at the dome of the bladder was less than 0.5 mV and low frequency. Myopotentials resembling smooth muscle were detected at electrodes near or within the trigone. A sensory response was reported with the use of pacing stimuli, with the sensation in the trigone being reported more often than the dome of the bladder. Stimulation in the trigone triggered sensory urgency and voiding in a patient with a history of overactive bladder. CONCLUSIONS: The use of multielectrode catheters to measure human bladder electrophysiologic activity is feasible. Issues with noise reduction still exist, though to a lesser extent with the multielectrode basket design than simple quadripolar one. Sensory responses to pacing stimuli may be useful for diagnostic and therapeutic purposes in the future.

Safety and efficacy of the NovaCross microcatheter in facilitating crossing of chronic total occlusion coronary lesions: a multicenter, single-arm clinical trial.

BACKGROUND: The aim of this study was to evaluate the safety and efficacy of the novel NovaCross microcatheter system in patients with ischemic heart disease due to coronary chronic total occlusions (CTO). METHODS: A total of 191 subjects between the ages of 25-80 years were recruited in 10 investigational sites. Each subject underwent a percutaneous coronary intervention (PCI) of a CTO lesion using the NovaCross microcatheter, equipped with expandable nitinol scaffolds to enhance guidewire penetration and crossing of the CTO lesion. The primary safety endpoint was procedural major adverse cardiac events [composite of death, myocardial infarction (MI), or urgent target vessel revascularization]. The primary efficacy endpoint was to assess the ability of the NovaCross microcatheter to successfully facilitate the placement of a guidewire beyond a native coronary CTO in the true vessel lumen. After the PCI, subjects remained in hospital until a 12-lead ECG and blood tests for cardiac biomarkers were taken at 3-6 h and 8-16 h post-procedure. RESULTS: No deaths, urgent revascularization, or urgent coronary artery bypass surgery were reported. The reported MI rate according to the protocol definition was 12.3%, and technical success was achieved in 75.3% of the subjects regardless of CTO procedure technique. In 89.2% of the subjects, the NovaCross succeeded in penetrating the proximal CTO cap, and in 25.8% of the subjects, the extendable portion of the NovaCross crossed the full length of the CTO lesion. CONCLUSIONS: The NovaCross met both the primary safety endpoint and the primary efficacy endpoint. We, therefore, conclude that the device is well tolerated, effective, and could be easily adopted by interventional cardiologists.

Intracardiac echocardiography to enable successful edge-to-edge transcatheter tricuspid valve repair in patients with insufficient TEE quality.

BACKGROUND: Transesophageal echocardiography (TEE) as a guiding tool for edge-to-edge transcatheter tricuspid valve repair (EETVr) using MitraClip (Abbott Vascular, Santa Clara, USA) may not offer sufficient image quality in a significant proportion of patients. OBJECTIVES: Intracardiac echocardiography (ICE) as additional guiding tool in EETVr with the MitraClip device. METHODS: Appropriate angulations of the ICE catheter to visualize each commissure of the tricuspid valve were established in 3D printed heart models. In a single tertiary-care center ICE was used to support EETVr as additional guidance when TEE image quality was insufficient. Procedural safety and outcomes up to 30-days were compared between ICE/TEE and TEE only guided patients. RESULTS: In 6 of 11 patients (54.5%) undergoing EETVr with MitraClip TEE alone was unsatisfactory, necessitating additional ICE guidance. In 4 of these 6 patients ICE enabled a successful completion of the procedure. The steering maneuvers identified in the 3D models were well applicable in all patients, providing examples for potential future ICE implementation in EETVr. Under both TEE alone (n = 5) and ICE (n = 6) guidance the rate of procedural complications was 0%. According to vena contracta values at discharge significant TR reduction was achievable in the treated cohort (p = 0.011). At 30-days follow-up one patient (ICE guided) died following global heart failure, not associated with the procedure itself. CONCLUSIONS: ICE guidance may offer an additional tool to guide EETVr with the MitraClip device in patients with poor TEE quality, as it enables successful results without impairing procedural safety.

Phasic pressure measurements for coronary and valvular interventions using fluid-filled catheters: Errors, automated correction, and clinical implications.

OBJECTIVES: We sought to develop an automatic method for correcting common errors in phasic pressure tracings for physiology-guided interventions on coronary and valvular stenosis. BACKGROUND: Effective coronary and valvular interventions rely on accurate hemodynamic assessment. Phasic (subcycle) indexes remain intrinsic to valvular stenosis and are emerging for coronary stenosis. Errors, corrections, and clinical implications of fluid-filled catheter phasic pressure assessments have not been assessed in the current era of ubiquitous, high-fidelity pressure wire sensors. METHODS: We recruited patients undergoing invasive coronary physiology assessment. Phasic aortic pressure signals were recorded simultaneously using a fluid-filled guide catheter and 0.014″ pressure wire before and after standard calibration as well as after pullback. We included additional subjects undergoing hemodynamic assessment before and after transcatheter aortic valve implantation. Using the pressure wire as reference standard, we developed an automatic algorithm to match phasic pressures. RESULTS: Removing pressure offset and temporal shift produced the largest improvements in root mean square (RMS) error between catheter and pressure wire signals. However, further optimization <1 mmHg RMS error was possible by accounting for differential gain and the oscillatory behavior of the fluid-filled guide. The impact of correction was larger for subcycle (like systole or diastole) versus whole-cycle metrics, indicating a key role for valvular stenosis and emerging coronary pressure ratios. CONCLUSIONS: When calibrating phasic aortic pressure signals using a pressure wire, correction requires these parameters: offset, timing, gain, and oscillations (frequency and damping factor). Automatically eliminating common errors may improve some clinical decisions regarding physiology-based intervention.

Nursing Practice With Transthoracic Intracardiac Catheters in Children: International Benchmarking Study.

BACKGROUND: Transthoracic intracardiac catheters are central catheters placed in the operating room at the conclusion of cardiac surgery for infants and children. Complications associated with these catheters (eg, bleeding, migration, premature removal, infection, leakage, and lack of function) have been described. However, no researchers have addressed the nursing management of these catheters in the intensive care unit, including catheter dressing and securement, mobilization of patients, and flushing the catheters, or the impact of these interventions on patients' outcomes. OBJECTIVES: To internationally benchmark current nursing practice associated with care of infants and children with transthoracic intracardiac catheters. METHODS: In a cross-sectional, descriptive study of nursing practice in infants and children with transthoracic intracardiac catheters, a convenience sample of bedside and advanced practice nurses was recruited to complete an online survey to benchmark current practice. The survey included questions on criteria for catheter insertion and removal, dressing care, flushing practice, securement, and mobilization of patients. RESULTS: Transthoracic intracardiac catheters are used by most centers that provide care for infants and children after open heart surgery. A wide range of practices was reported. CONCLUSIONS: Standardizing the use and care of transthoracic intracardiac catheters can improve the safety and efficacy of their use in infants and children and promote safe and early postoperative mobilization of patients.

Pathology Approaches to Determine Safety and Efficacy of Cardiac Ablation Catheters.

Cardiac electrophysiology utilizes nonimplantable, catheter-based devices for diagnosis and treatment of arrhythmias as well as electroanatomical mapping of cardiac chambers. Gross pathology and histopathological assessments in preclinical studies play critical roles in determining the safety and efficacy of cardiac ablation systems used to treat tachyarrhythmias. The pathologist must assess ablation sites, adjacent structures and organs, and downstream organs to characterize the effects of the ablation treatment and determine whether adverse local reactions, collateral injury, or downstream thromboembolism are present. Histopathological assessment serves as an adjunct to electroanatomical data in determining efficacy in preclinical studies. Histopathology is the standard in definitively demonstrating transmurality of ablation lesions, which is necessary for complete conduction block, as well as showing the linear or circumferential distribution of a contiguous, transmural ablation lesion necessary for electroanatomical isolation of entire target structures such as pulmonary veins and the cavotricuspid isthmus, which are involved in propagating certain arrhythmias. This article will detail gross and histological methods for the pathology assessment of preclinical studies evaluating the safety and/or efficacy of cardiac ablation catheter systems as well as discuss correlation of pathology data with other supporting evidence for safety and efficacy such as acute, electroanatomical data.

Fiberoptic Contact-Force Sensing Electrophysiological Catheters: How Precise Is the Technology?

BACKGROUND: Contact-force (CF) sensing catheters are increasingly used in electrophysiological procedures due to their efficacy and safety profile. As data about the accuracy of fiberoptic CF technology are scarce, we sought to quantify it using in vitro experiments. METHODS AND RESULTS: A force sensor was built with a flexible membrane to allow exact reference force measurements for each set of experiments. A TactiCath Quartz (TCQ) ablation catheter was brought in contact with the force sensor membrane in order to compare the TCQ force measurements to sensor reference force measurements. Measurements were performed at different tip angles (0°/perpendicular contact, 45°, 90°/parallel contact), with fluid irrigation, different degrees of catheter deflection, and using a sheath. The accuracy of the TCQ force measurements was 0.9 ± 0.9 g (0°), 0.8 ± 0.8 g (45°) and 1.2 ± 1.3 g (90°), 0.8 ± 0.7 g (irrigation), 0.8 ± 0.8 g (deflection), and 0.8 ± 0.9 g (sheath); this was not significantly different among all experimental conditions. The precision was ≤3.8%. CONCLUSION: CF measurements using a fiberoptic sensing technology show a high level of accuracy and precision, without being significantly influenced by tip angle, fluid irrigation, catheter deflection or use of a sheath.

Electromagnetic Contact-Force Sensing Electrophysiological Catheters: How Accurate is the Technology?

BACKGROUND: Contact-force (CF) sensing catheters are increasingly used in clinical electrophysiological practice due to their efficacy and safety profile. As data about the accuracy of this technology are scarce, we sought to quantify accuracy based on in vitro experiments. METHODS AND RESULTS: A custom-made force sensor was constructed that allowed exact force reference measurements registered via a flexible membrane. A Smarttouch Surround Flow (ST SF) ablation catheter (Biosense Webster, Diamond Bar, CA, USA) was brought in contact with the membrane of the force sensor in order to compare the ST SF force measurements to force sensor reference measurements. ST SF force sensing technology is based on deflection registration between the distal and proximal catheter tip. The experiment was repeated for n = 10 ST SF catheters, which showed no significant difference in accuracy levels. A series of measurements (n = 1200) was carried out for different angles of force acting to the catheter tip (0°/perpendicular contact, 30°, 60°, 90°/parallel contact). The mean absolute differences between reference and ST SF measurements were 1.7 ± 1.8 g (0°), 1.6 ± 1.2 g (30°), 1.4 ± 1.3 g (60°), and 6.6 ± 5.9 g (90°). Measurement accuracy was significantly higher in non-parallel contact when compared with parallel contact (P < 0.01). CONCLUSIONS: Catheter force measurements using the ST SF catheters show a high level of accuracy regarding differences to reference measurements and reproducibility. The reduced accuracy in measurements of 90° acting forces (parallel contact) might be clinically important when creating, for example, linear lesions.

Clinical and Procedural Outcomes of 5-French versus 6-French Sheaths in Transradial Coronary Interventions.

The radial artery has been increasingly used for its favorable safety profile. However, no conclusive data are available on the optimal sheath size. In particular, it is seemingly difficult to weight both advantages and disadvantages of narrower versus larger sheaths size. Despite several studies were performed to compare the use of 6-Fr to the smaller 5-Fr sheaths, these were mostly small, single center-studies, yielding various results.We performed a comprehensive meta-analysis of all available studies comparing the use of 5-Fr versus 6-Fr sheaths in coronary procedures through the TRA.Studies comparing a 5-Fr versus a 6-Fr sheaths were searched for in PubMed, the Cochrane Library, and ISI Web of Knowledge databases.Studies were deemed eligible if they only included patients undergoing transradial cardiac catheterization with 5-Fr or 6-Fr system and reported at least one of these parameters: contrast dye volume, procedural success, procedural time, access complications, radial artery occlusion, and bleedings.Odds ratio (OR) and the mean difference (MD) were respectively used for dichotomous and continuous variables as summary measures. Both the random-effects model and the fixed effect models were used for computation of meta-analyses. Heterogeneity was assessed by means of the Cochrane Q test. Metaregression was calculated using the unrestricted maximal likelihood random effects model.The use of a 5-Fr system is associated with a significant lower contrast medium administration (MD = -22.20 [-36.43 to -7.96], P < 0.01) and significantly reduces bleedings (OR = 0.58 [0.38-0.90], P = 0.02), without compromising procedural success (OR = 0.95 [0.53-1.69], P = 0.86) or procedure length (OR = 0.55 [-2.58 to 3.69], P = 0.73), compared to the 6-Fr system. Despite no significant difference was observed between the groups (OR = 0.88 [0.50-1.56], P = 0.67), at metaregression RAO incidence in the 5-Fr group was increasingly lower as the percentage of women included into the study increased (P = 0.02).Some potentially interesting technical details, such as sheath length, hydrophilic coating, or periprocedural anticoagulation, were not homogeneously reported in individual studies.Results of the present meta-analysis confirm the excellent safety profile of transradial procedures both with 5-Fr and 6-Fr system. A 5-Fr system could be preferred in patients with a higher bleeding propensity or kidney injury.

Right heart catheterisation: best practice and pitfalls in pulmonary hypertension.

Right heart catheterisation (RHC) plays a central role in identifying pulmonary hypertension (PH) disorders, and is required to definitively diagnose pulmonary arterial hypertension (PAH). Despite widespread acceptance, there is a lack of guidance regarding the best practice for performing RHC in clinical practice. In order to ensure the correct evaluation of haemodynamic parameters directly measured or calculated from RHC, attention should be drawn to standardising procedures such as the position of the pressure transducer and catheter balloon inflation volume. Measurement of pulmonary arterial wedge pressure, in particular, is vulnerable to over- or under-wedging, which can give rise to false readings. In turn, errors in RHC measurement and data interpretation can complicate the differentiation of PAH from other PH disorders and lead to misdiagnosis. In addition to diagnosis, the role of RHC in conjunction with noninvasive tests is widening rapidly to encompass monitoring of treatment response and establishing prognosis of patients diagnosed with PAH. However, further standardisation of RHC is warranted to ensure optimal use in routine clinical practice.

Impact of Catheter Sheath Insertion into the Radial Artery on Vascular Endothelial Function Assessed by Reactive Hyperemia Peripheral Arterial Tonometry.

The transradial approach has been used for coronary procedures, but this procedure carries a risk of injury to the endothelium of the radial artery. In this study, the vascular dysfunction caused by transradial catheterization was examined using reactive hyperemia peripheral arterial tonometry (RH-PAT), a recently developed technique for assessing endothelial function in digits, and the differences in injuries were compared according to the size of sheath.Forty-three patients undergoing transradial catheterization with 6-Fr sheaths (n = 17) or 4-Fr/5-Fr (non-6-Fr; n = 26) sheaths underwent RH-PAT using an Endo-PAT2000 before, the day after, and 6 months after catheterization. RH-PAT was assessed in the arm of sheath placement and in the other arm as a control.RH-PAT values decreased from 2.42 ± 0.67 before catheterization to 2.08 ± 0.41 the day after catheterization in the 6-Fr group (P = 0.031); this was more evident in patients with a longer procedure time (> 91 minutes). In contrast, the change in the non-6-Fr group was not significant. RH-PAT of the non-catheterized arm was unchanged in both groups. At 6 months after catheterization, RH-PAT values in the 6-Fr group had not completely returned to baseline.In conclusion, the insertion of a 6-Fr catheter sheath into the radial artery, especially with a longer procedure time, impaired vascular endothelial function assessed by RH-PAT the day after the procedure and was sustained for 6 months. Thus, the use of smaller size sheaths (< 6-Fr) with a shorter procedure should be considered when performing transradial catheterization.

Drug-coated balloon treatment of coronary artery disease: a position paper of the Italian Society of Interventional Cardiology.

Drug-coated balloons are a new tool for the treatment of patients with coronary artery disease. The main feature of this technology is a rapid and homogenous transfer of an antiproliferative drug (paclitaxel) to the vessel wall just at the time of balloon inflation, when neointimal proliferation, in response to angioplasty, is the highest. Moreover, drug-coated balloons share adjuntive advantages over stents: the absence of permanent scaffold and polymer, the respect of the original coronary anatomy, and limited inflammatory stimuli, thereby allowing for short-term dual antiplatelet therapy. To this day, a lot of devices are available in the market, with limited scientific data for the vast majority of them. Thus, the Italian scientific society of interventional cardiologists GISE decided to coordinate the efforts of a group of reknown experts on the field, in order to obtain a Position Paper on the correct use of drug-coated balloons in all the settings of coronary artery disease, giving a class of indication to each one, based on the clinical evidence. This Position Paper represents a quick reference for operators, investigators, and manufactures to promote the understanding and the correct use of the drug-coated balloon technology in everyday clinical practice.

[The comparison of thrombectomy catheters by primary transcutaneous coronary surgery].

Treatment results of 44 cases of myocardial infarction with ST segment elevation were analyzed. Patients were divided in 2 groups. The first group (n=21) received the transcutaneous coronary intervention with the use of catheters for rheolythic thrombectomy. The second group (n=23) received the intervention with catheters for the manual thrombectomy. Patients from the 1st group demonstrated reliably better results considering adequate reperfusion, registered angio- and electrocardiographically. There were no cases of arterial dissection or vessel perforation in both groups. There were two lethal hospital outcomes among patients of the manual thrombectomy group.

New re-entry device for revascularization of chronic coronary total occlusions: preliminary single Japanese center experience.

BACKGROUND: Although retrograde approach for coronary chronic total occlusion (CTO) has been introduced, the procedure is still time and resource consuming. A simplified antegrade approach mightbe another resort. The aim of this study was to evaluate a new device designed to facilitate guidewire re-entry into the true lumen of a CTO from the adjacent subintimal space. METHODS: Patients with CTO were entered into a prospective registry regardless of lesion characteristics. A new metal-tip catheter was used initially in primary use cases. If it created subintimal tracking, a new re-entry tool (a flat balloon with 2 exit ports offset by 180 degrees) was used as a platform to attempt guidewire penetration into the distal true lumen. In rescue use cases after unsuccessful conventional wiring, the re-entry procedure was subsequently attempted. RESULTS: In 11 CTO lesions attempted, device success was achieved in 8 cases (72.7%). Re-entry procedure success rate was higher in primary use cases (80%) compared to rescue use cases (33.3%). Retrograde approach was conducted immediately after unsuccessful antegrade procedure using this device in the other 3 cases and successful recanalization was achieved in all cases. All lesions were stented, resulting in TIMI 3 flow without major complications. CONCLUSION: A new coronary re-entry device may provide another strategic option in the antegrade approach to recanalize CTOs.