Echographic detection of latent severe thrombotic stenosis of the superior vena cava and innominate vein in patients with a pacemaker: integrated diagnosis using sonography, pulse Doppler, and color flow

Three simple but interesting transthoracic echocardiographic road maps for proximal superior vena cava visualisation in healthy young adults

Background

Although much is known about the technical aspects of inferior vena cava visualization, it is much less about its counterpart: the superior vena cava (SVC). The aims of this study therefore, were to describe in detail the different possible two dimensional echocardiographic SVC visualization techniques in healthy young adults and to provide a series of values for its dimensions and Doppler signals.

Methods

The proximal SVC visualization through the three transthoracic windows was initially established in several adult patients, with or without cardiovascular implantable devices. Subsequently a group of 70 completely healthy adults (35 males and 35 females) were studied to determine the values of SVC dimensions and its pulse Doppler signal characteristics. The visualization windows included: a) Modified apical 5-champber view, b) Modified parasternal short axis view of great vessels and c) Modified subcostal view. The SVC dimensions were measured 3–5 cm above the RA-SVC junction at the end of both hold cardiac and respiratory cycles (systole, diastole and inspiration/expiration, respectively). The peak pulse Doppler velocities were only measured at the end-held expiration.

Results

The largest end systolic proximal SVC dimensions at the end of the expiration and inspiration ranged from 8 to 14.0 mm (11 ± 2 mm) and 8.0–14.0 mm (11 ± 2 mm) respectively, and the highest S wave velocity ranged from 0.5 to 0.7 m/s (0.6 ± 0.0 m/s).

Conclusion

This study has provided a detailed technical description for transthoracic proximal SVC visualization in a group of 70 healthy adults and has furnished sets of values for its dimensions and Doppler signal parameters.

Upper Extremity Deep Vein Thrombosis and Asymptomatic Vein Occlusion in Patients With Transvenous Leads: A Systematic Review and Meta-Analysis

Aims: The presence of transvenous leads for cardiac device therapy may increase the risk of venous thromboembolisms. The epidemiology of these complications has not yet been determined systematically. Therefore, this study aims to determine (I) the incidence of symptomatic upper extremity deep vein thrombosis (UEDVT) and (II) the prevalence of asymptomatic upper extremity vein occlusion in patients with transvenous leads, both after the initial 2 months following lead implantation.

Methods: PubMed, EMBASE, and Cochrane Library were searched until March 31, 2020 to identify studies reporting incidence of UEDVT and prevalence of asymptomatic vein occlusion after the initial 2 months after implantation in adult patients with transvenous leads. Incidence per 100 patient years of follow-up (PY) and proportions (%) were calculated to derive pooled estimates of incidence and prevalence.

Results: Search and selection yielded 20 and 24 studies reporting on UEDVT and asymptomatic vein occlusion, respectively. The overall pooled incidence of UEDVT was 0.9 (95% CI 0.5–1.4) per 100PY after 2 months after lead implantation. High statistical heterogeneity was present among studies (I² = 82.4%; P = < 0.001) and only three studies considered to be at low risk of bias. The overall pooled prevalence of asymptomatic upper extremity vein occlusion was 8.6% (95% CI 6.0–11.5) with high heterogeneity (I² = 81.4%; P = <0.001). Meta-regression analysis showed more leads to be associated with a higher risk of UEDVT.

Conclusion: Transvenous leads are an important risk factor for symptomatic UEDVT, which may occur up to multiple years after initial lead implantation. Existing data on UEDVT after lead implantation is mostly of poor quality, which emphasizes the need for high quality prospective research. Asymptomatic vein occlusion is present in a substantial proportion of patients and may complicate any future lead addition.

Clinical Trial Registration: (URL: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020178136, Identifier: PROSPERO 2020 CRD42020178136).

Superior vena cava-right atrium junction flow-pattern post-transcatheter closure of patent foramen ovale

BACKGROUND

The patent foramen ovale (PFO) occluder is a bulky metallic device. Its impact on the normal blood flow at the superior vena cava-right atrial (SVC-RA) junction is not clear.

METHODS

We examined SVC-RA junction flow-pattern using pulsed-wave (PW) ultrasound Doppler in 21 patients (4 male, aged 52.7 ± 9 years) who underwent PFO device closure 4-120 months previously, in comparison with 21 age- and sex-matched controls (4 male, aged 51 ± 8.5 years) with structurally normal hearts.

RESULTS

Mean systolic flow velocity at the SVC-RA junction was 60 ± 11 cm/s in the PFO closure group and 64 ± 17 cm/s in the control group (P = 0.27). Mean diastolic blood flow velocity at the SVC-RA junction in those groups was 30 ± 8 and 35 ± 9 cm/s, respectively (P = 0.1).The mean systolic wave duration was 439 ± 52 ms in the PFO closure group and 422 ± 67 ms in the control group (P = 0.4). The mean diastolic wave duration was 320 ± 75 and 277 ± 88 ms, respectively (P = 0.12).

CONCLUSION

The study results show that transcatheter PFO closure does not affect the normal blood flow at the SVC-RA junction.

Sonology Demonstrates Flow Reversal Within Internal Jugular Vein Secondary to Occluded Innominate Vein and Stenotic Hemodialysis Arteriovenous Fistula

This case illustrates a rare finding of flow reversal within the internal jugular vein associated with innominate occlusion and ipsilateral arteriovenous fistula. The patient was an adult male who presented with extreme pain and swelling of the left upper extremity and an ipsilateral nonfunctioning hemodialysis shunt. Doppler waveforms demonstrated turbulence and retrograde flow of the internal jugular vein (IJV). Sonography demonstrated complete occlusion of the left innominate vein. Angiography confirmed the IJV flow reversal and the full extent of the innominate vein clot. Angiography also showed bilateral indwelling innominate stents, as well as visualized the retrograde flow from the IJV crossing left to right via the transfer sinus and descending caudally to the right IJV. As demonstrated in this case, ultrasound works well in tandem with special procedures.

Prevalence of Thromboembolic Disease IncludingSuperior Vena Cava and Brachiocephalic Veins

Thrombosis of the brachiocephalic veins or superior vena cava (SVC) is rare. This study was conducted to determine the prevalence and characteristics of thrombosis of brachiocephalic veins and SVC, and its association with symptomatic pulmonary embolism (PE). The prevalence of thrombosis involving the brachiocephalic veins and SVC was evaluated retrospectively at a university hospital during the 3-year period. Patients were identified by hospital records and review of computer-generated lists of of all venograms, contrast-enhanced chest computed tomography, and magnetic resonance angiograms of the upper extremity and SVC. Thrombosis of the brachiocephalic veins and SVC was diagnosed in 33 (0.03%) of 100,942 patients of all ages [(32 of 70,751 adult patients≥ 20 years; 0.04%)]. Twenty-three (70%) patients initially had secondary thrombosis with multiple risk factors: associated with malignancy in 14 (42%) patients, chronic disorders in 13 (39%) patients, central venous lines (CVL) and peripheral venous lines (PVL) in 9 (27%) patients, and thrombophilia in 10 (38%) of 26 patients. Swelling of the arm, head, and neck was present in 32 (97%) patients. Symptomatic PE developed before thrombosis being treated in 12 (36%) patients. All patients except eight (three, thrombolytic; five, thrombectomy) received anticoagulant therapy. Thrombosis of the SVC and brachiocephalic veins is an uncommon but serious complication in patients with malignancy, chronic disorders, CVL, PVL, and thrombophilia. Because it is important clinical problem with frequent PE, the patients with appropriate clinical findings should be diagnosed early with imaging tests and treated with anticoagulant drugs.

Superior vena cava echocardiography as a screening tool to predict cardiovascular implantable electronic device lead fibrosis

BACKGROUND

Currently there is no noninvasive imaging modality used to risk stratify patients requiring lead extractions. We report the novel use of superior vena cava (SVC) echocardiography to identify lead fibrosis and complex cardiac implantable electronic device (CIED) lead extraction. With an aging population and expanding indications for cardiac device implantation, the ability to deal with the complications associated with chronically implanted device has also increased.

METHODS

This was a retrospective analysis of Doppler echocardiography recorded in our outpatient Electrophysiology/Device Clinic office over 6 months. Images from 109 consecutive patients were reviewed.

RESULTS

62% (68/109) did not have a CIED and 38% (41/109) had a CIED. In patients without a CIED, 6% (4/68) displayed turbulent color flow by Doppler in the SVC, while 22% (9/41) of patients with a CIED displayed turbulent flow. Fisher's exact test found a statistically significant difference between the two groups (p value < 0.05). The CIED group was subdivided into 2 groups based on device implant duration (< 2 years vs. ≥ 2 years). Of the CIED implanted for ≥ 2 years, 27% (9/33) had turbulent flow in the SVC by Doppler, while no patients (0/8) with implant durations < 2 years demonstrated turbulent flow. Nine patients underwent subsequent lead extraction. A turbulent color pattern successfully identified all 3 patients that had significant fibrosis in the SVC found during extraction.

CONCLUSION

Our data suggests that assessing turbulent flow using color Doppler in the SVC may be a valuable noninvasive screening tool prior to lead extraction in predicting complex procedures.

Surgical management of superior vena cava syndrome following pacemaker lead infection: a case report and review of the literature

Superior vena cava (SVC) syndrome is a known but rare complication of pacemaker lead implantation, accounting for approximately less than 0.5% of cases. Its pathophysiology is due to either infection or endothelial mechanical stress, causing inflammation and fibrosis leading to thrombosis, and therefore stenosis of the SVC. Due to the various risks including thrombo-embolic complications and the need to provide symptomatic relief, medical and surgical interventions are sought early. We present the case of a 48-year Caucasian male who presented with localised swelling and pain at the site of pacemaker implantation. Inflammatory markers were normal, but diagnostic imaging revealed three masses along the pacemaker lead passage. A surgical approach using cardiopulmonary bypass and circulatory arrest was used to remove the vegetations. Culture from the vegetations showed Staphylococcus epidermidis. The technique presented here allowed for safe and effective removal of both the thrombus and infected pacing leads, with excellent exposure and minimal post-procedure complications.

Utility and safety of axillo-subclavian venous imaging with carbon dioxide (CO) prior to chronic lead system revisions

BACKGROUND

Prior to attempting placement of one or more electrodes to revise existing rhythm control devices, patency of the central veins should be documented, in view of a high incidence of significant chronic occlusions. Since iodinated contrast venography may be contraindicated in select situations, imaging of the axillo-subclavian venous system with gaseous carbon dioxide (CO(2)) was evaluated prospectively in 23 consecutive individuals who were considered for revision of previously implanted pacemaker or automatic cardioverter defibrillator lead systems.

METHODS

Approximately 20 mL of CO(2) were manually infused via CO(2) primed injection tubing into a vein at or above the level of the antecubital fossa ipsilateral to the side of prior lead placements. Digital subtraction imaging over the axillo-subclavian region, lower neck, and mediastinum was performed. Formal interpretation was obtained from one of three interventional radiologists and at least one electrophysiologist.

RESULTS

Significant venous occlusions were identified in five (22%) patients. Vascular access utilized for the subsequent 18 revisions performed included the imaged patent ipsilateral vein in 14 patients and the contralateral, right-sided subclavian venous system in three patients. One patient required epicardial left ventricular lead placement. There were no complications from venography.

CONCLUSIONS

Axillo-subclavian venography with gaseous CO(2) in patients undergoing pacemaker or implantable cardioverter defibrillator lead revisions is feasible and safe when use of iodinated dye is contraindicated. This technique should be employed in patients with azotemia, dye contrast allergies, or significant inflammation in the vicinity of the intravenous line insertion.

Acute Subclavian or Axillary Vein Occlusion During Biventricular Pacemaker Implantation

During biventricular pacemaker implantation, multiple punctures of the subclavian vein were performed and venous occlusion was apparent during the procedure, which in one case was stopped before lead insertion and in the other patient new access has to be forced through the occlusion by removing one of the already implanted leads. For implanting physicians, it is important to know that acute venous occlusion may occur during lead implantation.

Echocardiography of the superior vena cava

The anatomy and applied echocardiographic anatomy of the superior vena cava (SVC) are briefly described. Right supraclavicular interrogation of the SVC has been in use for many years, but supraclavicular two-dimensional (2-D) imaging of the SVC has been virtually ignored. We have recently shown that supraclavicular 2-D imaging can provide excellent views of the SVC and its main tributaries. Transthoracic echocardiography (TEE) is suitable for imaging of the lower (juxtaatrial) SVC. Persistence of a left SVC is an uncommon variant, diagnosed echocardiographically by coronary sinus dilatation and passage of contrast into it from a left arm vein. Extensive SVC compression by mediastinal masses is well known, but recently intravascular SVC obstruction has been increasingly reported as a complication of radiofrequency ablation for ectopic atrial tachycardia, for thrombosis of the SVC or its main tributaries following indwelling catheters, or following insertion of pacemaker leads. Doppler interrogation or TEE imaging of the SVC have been used in recent years to elucidate such pathology.

Venous Thrombosis and Stenosis After Implantation of Pacemakers and Defibrillators

Venous complications of pacemaker/ implantable cardioverter defibrillator (ICD) system implantation rarely cause immediate clinical problems. The challenge starts when patients come for system revision or upgrade. Numerous reports of venous complications such as stenosis, occlusions, and superior vena cava syndrome have been published. We reviewed current knowledge of these complications, management, and their impact on upgrade/revision procedures. One study has suggested that intravenous lead infection promotes local vein stenosis. Another found that the presence of a temporary wire before implantation is associated with an increased risk of stenosis. Although data for ICD leads is based only on three studies-it suggests that the rate of venous complications is very similar to that of pacing systems, and probably data from pacing leads can be extrapolated to ICD leads. Despite 40 years of experience with transcutaneous implanted intravenous pacing systems and dozens of studies, we were unable to identify clear risk factors (confirmed by independent studies) that lead to venous stenosis. Neither the hardware (lead size, number and material) nor the access site choice (cephalic cut down, subclavian or axillary puncture) appears to affect rate of venous complications. A few factors were proposed as predictors of severe venous stenosis/occlusion: presence of multiple pacemaker leads (compared to a single lead), use of hormone therapy, personal history of venous thrombosis, the presence of temporary wire before implantation, previous presence of a pacemaker (ICD as an upgrade) and the use of dual-coil leads. Anticoagulant therapy (for other reasons than pacemaker lead) seemed to have protective antithrombotic effect.

An Epicardial Subxiphoid Implantable Defibrillator Lead:. Superior Effectiveness After Failure of Standard Implants

A single epicardial implantable lead using the subxiphoid approach is described in this article. It consists of a single halo-shaped coil that is implanted under the inferior surface of the heart, including the right and left inferior ventricular surfaces. It has been implanted in four patients who could not be defibrillated with a transvenous system, even with the adjunct use of subcutaneous leads or left chest wall patch. Three of the patients had progressive heart failure due to ischemic myocardiopathy; the fourth patient had a dilated idiopathic myocardiopathy. The approach is simple and appears to be effective due to its ability to encompass the left and right ventricles. This vector seems to significantly lower the threshold for defibrillation, and may offer substantial benefit in the setting of high defibrillation thresholds with conventional leads, or when conventional systems are inadequate to achieve consistent defibrillation.

Symptomatic subclavian vein stenosis and occlusion in hemodialysis patients with transvenous pacemakers

The objective of this study was to determine the incidence and timing of complications associated with ipsilateral transvenous pacemakers and hemodialysis access, including subclavian vein stenosis and occlusion, and assess their impact on dialysis access patency. All patients who had pacemakers placed at St. Francis Medical Center were reviewed during the 10-year period from 1988 to 1998. Patients requiring chronic hemodialysis were identified and their demographic data, the presence of arm swelling, and fistula patency were noted. Development of subclavian vein stenosis and occlusion was documented by venography in symptomatic patients. The ultimate outcome of dialysis access was recorded. During the 10-year period 495 patients had transvenous pacemakers placed. Twenty patients were identified with renal failure requiring hemodialysis and 14 had hemodialysis access in the extremity ipsilateral to the pacemaker. Ten (10/14, 71%) patients developed symptoms of subclavian stenosis, including venous hypertension, high recirculation rate, arm swelling, pain, and neurologic symptoms. Eighty percent (8/10) of symptomatic patients had subclavian vein occlusion. All 10 symptomatic patients required ligation of the hemodialysis access to control symptoms. The four asymptomatic patients expired within 6 months of placement of the pacemaker or hemodialysis access from unrelated causes. There is a high incidence of complications in patients who have ipsilateral pacemakers and hemodialysis access. The presence of pacemaker electrodes in the subclavian vein and the flow associated with hemodialysis may accelerate the occurrence of subclavian venous stenosis and occlusion. Patients who did not develop symptoms may have expired before venous outflow obstruction could develop. Vascular surgeons and cardiac surgeons/cardiologists need to coordinate their procedures to avoid ipsilateral transvenous pacemakers and hemodialysis access.

Venous occlusion of the access vein in patients referred for lead extraction: influence of patient and lead characteristics

The aim of this study was to determine the effect of patient and lead characteristics on occlusion of the access vein in pacemaker and ICD patients. Contrast venography of the access vein was obtained in 89 patients (17 patients with an ICD) scheduled for lead extraction. The indication for extraction was infection in 57 patients (systemic infection in 9) and lead malfunction in 32 patients. In 6 of the 89 patients, leads were introduced in both the right and left subpectoral area, resulting in a total of 95 venous entry sites. In 22 of these entry sites one lead was present, in 61 two leads, in 11 three, and in 1 four leads. The vessel patency was graded open or occluded. Occlusion of the subclavian vein occurred in four (13%) patients with lead malfunction versus 18 (32%) patients with infection (P = 0.07). In patients with systemic infection, 5 of 9 showed venous occlusion (P = 0.01 when compared to patients with malfunction, odds ratio 8.75, 95% confidence interval 1.21-64.11). Considered per entry site, the incidence of occlusion was 7 of 22 with one lead present, 17 of 61 with two leads, 0 of 11 with three leads, and 0 of 1 with four leads (P = 0.13). No patient had a superior vena caval occlusion. Patients with systemic infection have an increased risk of occlusion of the access vein. On the contrary, the study found no support for the concept that the risk of venous occlusion increases with a higher number of leads present.

Color Doppler sonographic finding of retrograde jugular venous flow as a sign of innominate vein occlusion

Occlusion or stenosis of the superior vena cava, the innominate vein, or both is an important clinical problem that requires prompt diagnosis. To confirm a suspected occlusion, imaging studies revealing the obstruction and the presence of collateral venous routes are needed. Color Doppler sonography (CDUS) is widely used to evaluate suspected venous thrombosis and collateral pathways. We present the CDUS findings in 2 cases of innominate vein occlusion. In case 1, CDUS of the neck and left upper arm, which harbored a permanent hemodialysis access, showed engorged veins in the upper arm, a patent dialysis access, and some collateral veins in the axilla. The subclavian and internal jugular veins were patent, but the flow in the left internal jugular vein was reversed. The left innominate vein was occluded. In case 2, CDUS of the upper arms showed that the veins, the dialysis access in the left upper arm, and the subclavian and jugular veins were patent, but the flow in the left internal jugular vein and in the right subclavian vein was reversed. Collateral veins were seen in the right axillary region. Both innominate veins were occluded. The resulting collateral pathways, ie, retrograde flow in the ipsilateral jugular vein crossing to the contralateral jugular vein through dural sinuses, were confirmed by venography in both cases.

Experience with a low profile bipolar, active fixation pacing lead in pediatric patients

Continued miniaturization of permanent pacing systems has promoted use of this technology in younger and smaller pediatric patients. Intermedics ThinLine 438-10 active fixation pacing leads (4.5 Fr lead body) were implanted in 26 patients (17 males/9 females; 9.9 +/- 6.9 years). Twenty of 26 patients received dual chamber systems, 6 of 26 patients single lead systems. Each patient has been followed 3 months. Pacemaker analysis at implant and 6 months later evaluated pulse width thresholds at 2.5 V (atrial 0.07 +/- 0.02 vs 0.13 +/- 0.02 ms [P = 0.01]; ventricular 0.08 +/- 0.04 ms vs 0.20 +/- 0.04 ms [P = 0.01]); sensing thresholds (atrial 4.1 +/- 0.41 mV vs 4.0 +/- 4.2 mV [P = NS]; ventricular 9.7 +/- 0.72 vs 9.3 +/- 0.94 mV [P = NS]); and impedance (atrial 345 +/- 12 vs 370 +/- 120 O [P = 0.04]; ventricular 412 +/- 17 vs 458 +/- 190 O [P < 0.01]). One volt lead failed with exit block at approximately 6 weeks. The youngest (9 months to 5 years) and smallest (6.5-18.0 kg) ten patients have each shown by venography to have at least mild venous stenosis at the lead(s) insertion site; five patients demonstrated collateral formation around asymptomatic obstruction, with no thrombus formation. The Intermedics 438-10 ThinLine pacing lead has demonstrated good and stable early postimplant electrical parameters. Angiographic evaluation in our smaller patients has shown evidence for asymptomatic venous obstruction.