Venous access and long-term pacemaker lead failure: comparing contrast-guided axillary vein puncture with subclavian puncture and cephalic cutdown

Ultrasound-guided versus fluoroscopy-guided axillary vein puncture for cardiac implantable electronic device implantation: a meta-analysis enrolling 1257 patients

INTRODUCTION

Ultrasound-guided (Echo-AVP) and Fluoroscopy-guided Axillary Vein Puncture (Fluoro-AVP) are both acknowledged as safe and effective techniques for transvenous implantation of leads for cardiac implantable electronic devices (CIEDs). Nonetheless, it is still debated which of the two techniques has a better safety and efficacy profile. Therefore, we performed a meta-analysis to evaluate the efficacy and safety of Echo-AVP versus Fluoro-AVP for CIEDs implantation.

METHODS

We systematically searched Medline, Embase and Cochrane electronic databases up to May 15th, 2024, for studies that evaluated the efficacy and safety of Echo-AVP and Fluoro-AVP reporting at least one clinical outcome of interest. The primary efficacy endpoint was acute procedural success and the primary safety endpoint was a composite endpoint of pneumothorax, pocket hematoma/bleeding, pocket infection and inadvertent arterial puncture. The effect size was estimated using a random-effect model as Odds Ratio (OR) and Mean Difference (MD) with relative 95% Confidence Interval (CI).

RESULTS

Overall, 4 studies were included, which enrolled 1257 patients (Echo-AVP: 373 patients; Fluoro-AVP: 884 patients). Echo-AVP led to a significant reduction in the primary safety endpoint (OR: 0.41; p = 0.0009), risk of inadvertent arterial puncture (OR: 0.29; p = 0.003) and fluoroscopy time ( MD: -105.02; p = 0.008). No differences were found between Echo-AVP and Fluoro-AVP for acute procedural success (OR: 0.77; p = 0.27), pneumothorax (OR: 0.66; p = 0.60), pocket hematoma/bleeding (OR: 0.68; p = 0.30), pocket infection (OR: 0.66; p = 0.60), procedural time (MD: 1.99; p = 0.65), success rate at first attempt (OR: 1.25; p = 0.34) and venous access time (MD: -0. 25; p = 0.99).

CONCLUSION

Echo-AVP proved to reduce significantly the primary safety endpoint, inadvertent arterial puncture and fluoroscopy time compared to Fluoro-AVP.

Safety and Efficiency of Cephalic Vein Puncture by Modified Seldinger Technique Compared to Subclavian Vein Puncture for Cardiac Implantable Electronic Devices

INTRODUCTION

The establishment of venous access is one of the driving factors for complications during implantation of pacemakers and defibrillators (cardiac implantable electronic devices [CIED]). Recently, a novel approach of accessing the cephalic vein for CIED by cephalic vein puncture (CVP) using a modified Seldinger technique has been described, promising high success rates and simplified handling with steeper learning curves. In this single-center registry, we analyzed the safety and efficiency of CVP to SVP access after defining CVP as the primary access route in our center.

METHODS

A total of 229 consecutive patients receiving a CIED were included in the registry. Sixty-one patients were implanted by primary or bail-out SVP; 168 patients received primary cephalic preparation and CVP was performed when possible, using a hydrophilic transradial sheath.

RESULTS

Implantation of at least one lead via CVP was successful in 151 of 168 patients (90%), and implantation of all leads was possible in 122 of 168 patients (72.6%). Total implantation times and fluoroscopy times and doses did not differ between CVP and SVP implantations. Pneumothorax occurred in 0/122 patients implanted via CVP alone, but 8/107 (7.5%) patients received at least one lead via SVP.

CONCLUSION

Our data confirms high success rates of the CVP for CIED implantation. Moreover, this method can be used without significantly prolonging the total procedure time or applying fluoroscopy dose compared to the highly efficient SVP while showing lower overall complication rates.

Reel Versus Twiddler Syndrome in a Patient With a Pacemaker: A Case Report of Iatrogenic Manipulation

Twiddler syndrome is a rare entity in which patient manipulation causes lead dislocation with lead retraction. Reel syndrome, on the other hand, is observed after external manipulation, intentional or unintentional, in which the leads move along their transverse axis and is considered a variant of Twiddler syndrome. We present the clinical case of a 91-year-old female who, after pacemaker implantation, presented with dizziness and chest discomfort following constant manipulation of the pacemaker, resulting in complete retraction of the lead tip into the pouch, which is unusual in the literature to date.

Axillary vein puncture versus cephalic vein cutdown for cardiac implantable electronic device implantation: A meta-analysis

INTRODUCTION

Cephalic vein cutdown (CVC) and axillary vein puncture (AVP) are both recommended for transvenous implantation of leads for cardiac implantable electronic devices (CIEDs). Nonetheless, it is still debated which of the two techniques has a better safety and efficacy profile.

METHODS

We systematically searched Medline, Embase, and Cochrane electronic databases up to September 5, 2022, for studies that evaluated the efficacy and safety of AVP and CVC reporting at least one clinical outcome of interest. The primary endpoints were acute procedural success and overall complications. The effect size was estimated using a random-effect model as risk ratio (RR) and relative 95% confidence interval (CI).

RESULTS

Overall, seven studies were included, which enrolled 1771 and 3067 transvenous leads (65.6% [n = 1162] males, average age 73.4 ± 14.3 years). Compared to CVC, AVP showed a significant increase in the primary endpoint (95.7 % vs. 76.1 %; RR: 1.24; 95% CI: 1.09-1.40; p = .001) (Figure 1). Total procedural time (mean difference [MD]: -8.25 min; 95% CI: -10.23 to -6.27; p < .0001; I2  = 0%) and venous access time (MD: -6.24 min; 95% CI: -7.01 to -5.47; p < .0001; I2  = 0%) were significantly shorter with AVP compared to CVC. No differences were found between AVP and CVC for incidence overall complications (RR: 0.56; 95% CI: 0.28-1.10; p = .09), pneumothorax (RR: 0.72; 95% CI: 0.13-4.0; p = .71), lead failure (RR: 0.58; 95% CI: 0.23-1.48; p = .26), pocket hematoma/bleeding (RR: 0.58; 95% CI: 0.15-2.23; p = .43), device infection (RR: 0.95; 95% CI: 0.14-6.60; p = .96) and fluoroscopy time (MD: -0.24 min; 95% CI: -0.75 to 0.28; p = .36).

CONCLUSION

Our meta-analysis suggests that AVP may improve procedural success and reduce total procedural time and venous access time compared to CVC.

UltraSound Axillary Vein Access (USAA): Learning curve and randomized comparison to traditional venous access for cardiac device implantation

BACKGROUND

Many techniques exist for venous access (VA) during cardiac implantable electronic device (CIED) implantation.

OBJECTIVE

We sought to evaluate the learning curve with ultrasound (US) guided axillary vein access (USAA).

METHODS

Single-center prospective randomized controlled trial of patients undergoing CIED implantation. Patients were randomized in a 2:1 fashion to USAA versus conventional VA techniques. The primary outcomes were the success rates, VA times and 30-day complication rates.

RESULTS

The study included 100 patients (age 68 ± 14 years, BMI 27 ± 4 kg/m² ). USAA was successful in 66/70 implants (94%). Initial attempts at conventional VA included 47% axillary (n = 14), 30% (n = 9) cephalic, and 23% (n = 7) subclavian. The median access time was longer for USAA than conventional access (8.3 IQR 4.2-15.3 min vs. 5.2 IQR 3.4-8.6 min, p = .009). Among the five inexperienced USAA implanters, there was a significant improvement in median access time from first to last tertile of USAA implants (17.0 IQR 7.0-21.0 min to 8.6 IQR 4.5-10.8 min, p = .038). The experienced USAA implanter had similar access times with USAA compared with conventional access (4.0 IQR 3.3-4.7 min vs. 5.2 IQR 3.4-8.6 min, p = .15). Venograms were less common with USAA than conventional access (2% vs. 33%, p < .0001). The 30-day complication rate was similar with USAA (n = 4/70, 6%) versus conventional (n = 3/30, 10%, p = .44).

CONCLUSION

Although the success rate with USAA was high, there was a significant learning curve. Once experienced with the USAA technique, there is the potential for reduced complications without adding to the procedure duration.

Pacemaker electrode rupture causes recurrent syncope: A case report

BACKGROUND

Currently, the implantation of permanent cardiac pacemakers entails mostly subclavian vein puncture, which is relatively simpler and easier to master. However, due to individual differences, some patients carry a narrow space between the clavicle and the first rib. If the range of activity of the upper limb is increased, the friction between the electrode wire and the bone gap leads to the breakage of the electrode wire, which is manifested by poor pacemaker perception and pacing.

CASE SUMMARY

A 68-year-old woman underwent permanent pacemaker implantation in our hospital because of third-degree atrioventricular block 6 years ago. At that time, the patient was recommended to have a dual-chamber permanent pacemaker implantation, and finally chose a single-chamber permanent pacemaker because she could not afford the cost. The patient has repeatedly lost consciousness for no obvious reason in the past 3 d, and went to our hospital for treatment. The chest X-ray showed that the pacemaker electrode was broken. After the patient was given a pacemaker electrode replacement, the patient did not continue to lose consciousness.

CONCLUSION

Because the electrodes implanted in the subclavian approach are close to the clavicle and the first rib, the pacemaker electrodes may wear out. If the patient loses consciousness again after the pacemaker is implanted, we should consider whether there is a pacemaker. The possibility of electrode breakage, and timely help the patient to replace the new pacemaker electrodes.

Vascular Accesses in Cardiac Stimulation and Electrophysiology: An Italian Survey Promoted by AIAC (Italian Association of Arrhythmias and Cardiac Pacing)

Simple Summary

Both cardiac implantable electronic device (CIED) implantations and electrophysiology procedures require vascular access to reach the heart through vessels. Different types of access carry different rates of complications. Safety and ease of vascular access are the main targets of physicians; in fact, each complication causes morbidity and raises costs. To avoid complications, the use of ultrasound-guided vessel puncture and closure devices is increasing in frequency. We conducted a survey in Italian centers to outline common practice; an uneven pattern of habits emerged. Hopefully, recently published scientific society consensus statements will lead to an improvement in physicians’ practice. The survey highlights that there is an unmet need for dedicated courses, particularly for ultrasound-guided vessel puncture.

Abstract

Cardiac implantable electronic device (CIED) implants and electrophysiological procedures share a common step: vascular access. On behalf of the AIAC Ricerca Investigators’ Network, we conducted a survey to outline Italian common practice regarding vascular access in EP-lab. All Italian physicians with experience in CIED implantation and electrophysiology were invited to answer an online questionnaire (from May 2020 to November 2020) featuring 20 questions. In total, 103 cardiologists (from 92 Italian hospitals) answered the survey. Vascular access during CIED implants was considered the most complex step following lead placement by 54 (52.4%) respondents and the most complex for 35 (33.9%). In total, 54 (52.4%) and 49 (47.6%) respondents considered the cephalic and subclavian vein the first option, respectively (intrathoracic and extrathoracic subclavian/axillary vein by 22 and 27, respectively). In total, 45 (43.7%) respondents performed close arterial femoral accesses manually; only 12 (11.7%) respondents made extensive use of vascular closure devices. A total of 46 out of 103 respondents had experience in ultrasound-guided vascular accesses, but only 10 (22%) used it for more than 50% of the accesses. In total, 81 (78.6%) respondents wanted to increase their ultrasound-guided vascular access skills. Reducing complications is a goal to reach in cardiac stimulation and electrophysiological procedures. Our survey shows the heterogeneity of the vascular approaches used in Italian centres. Some vascular accesses were proved to be superior to others in terms of complications, with ultrasound-guided puncture as an emerging technique. More effort to produce the standardization of vascular accesses could be made by scientific societies.

Perioperative complications after pacemaker implantation: higher complication rates with subclavian vein puncture than with cephalic vein cutdown

PURPOSE

The cephalic vein cutdown (CVC) and the subclavian puncture (SP) is the most common access for pacemaker implantation. The purpose of this study was to compare the peri-/postoperative complications of these approaches.

METHODS

A retrospective analysis of the quality assurance data of the state of North Rhine-Westphalia was performed to evaluate the peri-/postoperative complications of first pacemaker implantation according to the venous access. The primary endpoint was defined as the occurrence of one of the following: asystole, ventricular fibrillation, pneumothorax, hemothorax, pericardial effusion, pocket hematoma, lead dislocation, lead dysfunction, postoperative wound infection or other complication requiring intervention. Descriptive analysis was done via absolute, relative frequencies and Odds Ratio. Fisher's exact test was used for comparison of the both study groups.

RESULTS

From 139,176 pacemaker implantations from 2010 to 2014, 15,483 cases were excluded due to other/double access. The median age was 78 years and the access used was CVC for 75,251 cases (60.8%) and SP for 48,442 cases (39.2%). The implanted devices were mainly dual-chamber pacemakers (73.9% in the CVC group and 78.4% in the SP group), followed by single-chamber pacemakers VVI (24.9% and 19.9% in the CVC and SP group respectively). There were significantly fewer peri/postoperative complications in the CVC group compared to the SP group (2.49% vs. 3.64%, p = 0.0001, OR 1.47; 95% CI 1.38-1.57).

CONCLUSIONS

CVC as venous access for pacemaker implantation has significantly fewer peri/postoperative complications than SP and appears to be an advantageous technique.

Axillary vein access using ultrasound guidance, Venography or Cephalic Cutdown-What is the optimal access technique for insertion of pacing leads?

We reviewed the different approaches used for central vein access during insertion of cardiac implantable electronic devices. The benefits and hazards of each approach (cephalic vein cutdown, axillary vein cannulation using venography and ultrasound) are discussed. Each approach has its advantages and hazards that need to be considered for the individual patient and balanced against the skills of the operator. The benefits of ultrasound guided venous access in reducing radiation exposure to the patient and implanter, avoiding the need for angiographic contrast and in minimizing the risk of pneumothorax and inadvertent arterial puncture are highlighted. Trainees should be taught each approach to deal with patient variability. Ultrasound guidance should be considered as a mainstream option for most patients.

Utility of Caudal Angulation for Venous Access under Fluoroscopic Guidance during Cardiovascular Implantable Electronic Device Implantation

BACKGROUND

Axillary venous access is preferred for CIED implantation. The procedure is usually performed under fluoroscopic guidance in anteroposterior (A-P) view. However, there is a lack of perception of depth in this view with a fear of creating complications. Caudal fluoroscopy (adding 30°-35° caudal angulation to A-P projection) has been proposed to circumvent this problem.

OBJECTIVE

The aim of this study was to elucidate the advantages of caudal fluoroscopy using fluoroscopic images, contrast venograms, and CT angiography images of axillary vein.

METHODS

The fluoroscopic images and contrast venograms obtained in the A-P view were compared with caudal fluoroscopy in patients undergoing CIED implantation at our centre. Also, the CT angiography images of axillary vein were reconstructed to understand the relative anatomy of the vein and the underlying lung parenchyma, simulating these 2 projections.

RESULTS

The CT angiography images, contrast venograms, and fluoroscopic images confirmed that caudal fluoroscopy allows better visualization of the vein in relation to the lung parenchyma and rib cage. Analysis of fluoroscopic images revealed that the bend of the first rib formed a conical prominence in caudal fluoroscopy. This served as an important bony landmark for successful venous access, which was usually obtained while the needle was being directed towards this prominence in caudal fluoroscopy.

CONCLUSIONS

The proposed advantages of caudal fluoroscopy for CIED implantation have been elucidated by analysis of CT angiography images, contrast venograms, and fluoroscopic images.

Multi-lead cephalic venous access and long-term performance of high-voltage leads

BACKGROUND

Cardiac resynchronization therapy-defibrillator (CRT-D) implantation via the cephalic vein is feasible and safe. Recent evidence has suggested a higher implantable cardioverter-defibrillator (ICD) lead failure in multi-lead defibrillator therapy via the cephalic route. We evaluated the relationship between CRT-D implantation via the cephalic and ICD lead failure.

METHODS

Data was collected from three CRT-D implanting centers between October 2008 and September 2017. In total 633 patients were included. Patient and lead characteristics with ICD lead failure were recorded. Comparison of "cephalic" (ICD lead via cephalic) versus "non-cephalic" (ICD lead via non-cephalic route) cohorts was performed. Kaplan-Meier survival and a Cox-regression analysis were applied to assess variables associated with lead failure.

RESULTS

The cephalic and non-cephalic cohorts were equally male (81.9% vs. 78%; p = .26), similar in age (69.7 ± 11.5 vs. 68.7 ± 11.9; p = .33) and body mass index (BMI) (27.7 ± 5.1 vs. 27.1 ± 5.7; p = .33). Most ICD leads were implanted via the cephalic vein (73.5%) and patients had a mean of 2.9 ± 0.28 leads implanted via this route. The rate of ICD lead failure was low and statistically similar between both groups (0.36%/year vs. 0.13%/year; p = .12). Female gender was more common in the lead failure cohort than non-failure (55.6% vs. 17.9%, respectively; p = .004) as was hypertension (88.9% vs. 54.2%, respectively, p = .038). On multivariate Cox-regression, female sex (p = .008; HR, 7.12 [1.7-30.2]), and BMI (p = .047; HR, 1.12 [1.001-1.24]) were significantly associated with ICD lead failure.

CONCLUSION

CRT-D implantation via the cephalic route is not significantly associated with premature ICD lead failure. Female gender and BMI are predictors of lead failure.

Strategies to Promote Long-Term Cardiac Implant Site Health

In the past several decades there has been a continuous growth in the field of cardiac implantable electronic devices (CIED) implantation procedures as well as their technological development. CIEDs utilize transvenous leads that are introduced into the heart via the axillary, subclavian, or cephalic veins, as well as a devices generator that is implanted in a subcutaneous pocket, typically in the pre-pectoral region. Despite this significant improvement, complication rates range from 1-6% with current implant tools and techniques. In this review we will discuss the three central parts of the CIED implantation procedure, their impact on implantation site, infections, and possibilities for its prevention.

Ultrasound-guided Axillary Vein Puncture in Cardiac Lead Implantation: Time to Move to a New Standard Access?

Cardiac stimulation therapy has evolved significantly over the past 30 years. Currently, cardiac implantable electronic devices (CIED) are the mainstream therapy for many potentially lethal heart conditions, such as advanced atrioventricular block or sustained ventricular tachycardia or fibrillation. Despite sometimes being lifesaving, the implant is surgical and therefore carries all the inevitable intrinsic risks. In the process of technology evolution, one of the most important factors is to make it safer for the patient. In the context of CIED implants, complications include accidental puncture of intrathoracic structures. Alternative strategies to intrathoracic subclavian vein puncture include cephalic vein dissection or axillary vein puncture, which can be guided by fluoroscopy, venography or, more recently, ultrasound. In this article, the authors analyse the state of the art of ultrasound-guided axillary vein puncture using evidence from landmark studies in this field.

Intermittent Pacemaker Malfunction Caused by Continuous Compression of the Lead by the Clavicle (Subclavian Crush Syndrome)

Subclavian vein access is still one of the most favoured access options for cardiac implantable electronic device (CIED) implantation. For the physician, the technique is reasonably familiar and easy to carry out. However, this has several potential complications. In this case, we present a late complication of subclavian access. The patient presented with intermittent loss of pacemaker output, which caused him to experience several syncopal events. In the acute setting, we changed the lead polarity and achieved a good outcome. Further management of this situation consisted of removal and replacement of the damaged lead.

Triple lead cephalic versus subclavian vein approach in cardiac resynchronization therapy device implantation

Cardiac resynchronization therapy (CRT) device implantation is associated with severe complications including pneumo- and hemothorax. Data on a sole cephalic vein approach (sCV), potentially preventing these complications, are limited. The aim of our study was to compare a sole cSV with a subclavian vein approach (SV) in CRT implantations with respect to feasibility and safety. We performed a prospective cohort study enrolling twenty-four consecutive de-novo CRT implantations (group A) using a sCV at two centers. Fifty-four age-matched CRT patients implanted via the SV served (group B) as reference. Procedural success rate and complications were recorded during a follow-up of 4 weeks. All CRTs could be implanted in group A, with 91.7% using cephalic access alone. In group B, CRT implantation was successfully performed in 96.3%. Procedure and fluoroscopy duration were similar for both groups (sCV vs. SV: 119 ± 45 vs. 106 ± 31 minutes, 17 ± 9 vs 14 ± 9 minutes). Radiation dosage was higher in sCV group vs. SV (2984 ± 2370 vs. 1580 ± 1316 cGy*cm²; p = 0.001). There was no case of a pneumothorax in group of sCV, while two cases were observed using SV. Overall complication rate was similar (sCV: 13.0% vs. SV: 12.5%). de-novo CRT implantation using a triple cephalic vein approach is feasible. Procedure duration and complication rates were similar, while radiation dosage was higher in the sCV compared to the SV approach. Despite its feasibility in the clinical routine, controlled prospective studies with longer follow-up are required to elucidate a potential benefit with respect to lead longevity.

Long-term reliability of the defibrillator lead inserted by the extrathoracic subclavian puncture

BACKGROUND

As the transvenous defibrillator lead is fragile and its failure may cause a life-threatening event, reliable insertion techniques are required. While the extrathoracic puncture has been introduced to avoid subclavian crush syndrome, the reports on the long-term defibrillator lead survival using this approach, especially the comparison with the cephalic cutdown (CD), remain scarce. We aimed to evaluate the long-term survival of the transvenous defibrillator lead inserted by the extrathoracic subclavian puncture (ESCP) compared with CD.

METHODS

Between 1998 and 2011, 324 consecutive patients who underwent an implantable cardioverter-defibrillator (ICD) implantation in Hokkaido University Hospital were included. ICD leads were inserted by CD from 1998 to 2003 and by contrast venography-guided ESCP thereafter. Lead failure was defined as a nonphysiologic high-rate oversensing with abnormal lead impedance or highly elevated sensing and pacing threshold.

RESULTS

Of 324 patients, CD was used in 37 (11%) and ESCP in 287 patients (89%). During the median follow-up of 6.2 years (IQR:3.2-8.3), 7 leads (2 in CD and 5 leads in ESCP group) failed. All patients with lead failure in ESCP group were implanted with either SJM Riata (n = 1) or Medtronic Fidelis lead (n = 4). Five-year lead survival was 93.8% (CI95%:77.3-98.4%) in CD compared with 99.1% (CI95%:96.6-99.8%) in ESCP group (P = 0.903). Univariate Cox regression analysis showed that the use of Fidelis or Riata lead was the strong predictor of the ICD lead failure (HR 13.8, CI95%:2.9-96.5; P = 0.001).

CONCLUSIONS

Contrast venography-guided extrathoracic puncture ensures the reliable long-term survival in the transvenous defibrillator leads.

Puncture of the Axillary Vein for the Implant for Electronic Cardiac Devices

Introduction: The obtaining of venous access for implantation of implantable electronic cardiac devices (IECDs) has been traditionally made by intrathoracic subclavian vein puncture (SVP) or cephalic vein phlebotomy (CVP). Evidence indicates, however, the increased risk of short-term and long-term complications with SVP due to the fact that it is intrathoracic access and the risk of compression of the electrodes by the costoclavicular ligament, leading to different types of defects. CVP, in turn, has been associated with a failure rate that reaches 45%. Axillary vein puncture (AVP) has been described in the literature and is presented here as an alternative to the two techniques mentioned. Methods: A PubMed survey was conducted on articles that mention the AVP, SVP and CVP techniques and compare them to the immediate, short and long term results and success rates for obtaining venous access. Emphasis was placed on comparisons between the various AVP techniques. Conclusion: The AVP technique for obtaining venous access presents some variations among the different authors. It has CVP-like safety, success rates comparable to those of the subclavian vein, and better medium and long term results for electrode function.

Punção da Veia Axilar para o Implante de Dispositivos Cardíacos Eletrônico

Introdução: A obtenção do acesso venoso para implante de dispositivos cardíacos eletrônicos implantáveis (DCEIs) tem sido tradicionalmente feita por meio da punção da veia subclávia intratorácica (PVS) ou por fl ebotomia da veia cefálica (FVC). Evidências apontam, entretanto, para o risco aumentado de complicações a curto e longo prazos com a PVS pelo fato de ser um acesso intratorácico e pelo risco de compressão dos eletrodos pelo ligamento costoclavicular, levando a diferentes tipos de defeitos. A FVC, por sua vez, tem sido associada à taxa de insucesso que chega a 45%. A punção da veia axilar (PVA) tem sido descrita na literatura e é apresentada, aqui, como alternativa às duas técnicas mencionadas. Métodos: Realizou-se uma pesquisa pelo PubMed sobre artigos que mencionam as técnicas de PVA, PVS e FVC e que as comparam quanto aos resultados imediatos, a curto e longo prazos e taxas de sucesso para a obtenção do acesso venoso. Deu-se ênfase às comparações entre as diversas técnicas de PVA. Conclusão: A técnica de PVA para obtenção do acesso venoso apresenta algumas variações entre os diversos autores. Ela tem segurança semelhante à da FVC, taxas de sucesso comparáveis às da veia subclávia e melhores resultados a médio e a longo prazos para a função dos eletrodos.