Temporary transcoronary pacing by coated guidewires

Coronary Guidewires in Temporary Cardiac Pacing and Assessment of Myocardial Viability: Current Perspectives and Future Directions

Intracoronary guidewires used in percutaneous coronary intervention can also be configured to provide temporary ventricular pacing. Trans coronary electrophysiological parameters recorded by employing coronary guidewires may have a potential role in assessing myocardial viability and could provide a means to make an immediate on-table decision about revascularisation. To date, some small studies have demonstrated the safety of this technique in temporary cardiac pacing, but further research is required to refine this approach and establish its clinical utility in myocardial viability assessment. In this review we discuss the potential role of trans coronary electrophysiology in the assessment of myocardial viability.

Intracoronary Pacing during "Chimney Technique" in Transcatheter Aortic Valve-in-Valve Implantation: An Alternative Temporary Rapid Ventricular Stimulation?

Temporary rapid ventricular pacing (TRVP) is required during transcatheter aortic valve implantation (TAVI) in order to reduce cardiac output and to facilitate balloon aortic valvuloplasty, prosthesis deployment, and post-deployment balloon dilation. The two most frequently used TRVP techniques are right endocardial (RE)-TRVP and retrograde left endocardial temporary rapid ventricular pacing (RLE)-TRVP. The first one could be responsible for cardiac tamponade, one of the most serious procedural complications during TAVI, while the second one could often be unsuccessful. Intracoronary (IC)-TRVP through a coronary guidewire has been described as a safe and efficient procedure that could avoid such complications. We describe two clinical cases in which IC-TRVP has been effectively used during valve-in-valve TAVI with coronary protection via the "chimney technique", after unsuccessful RLE-TRVP.

Trans-coronary pacing via Rota wire prevents bradycardia during rotational atherectomy: a case report

Back ground

Rotational atherectomy (RA) is used for plaque modification in patients with heavily calcified coronary lesions. Rotational atherectomy can induce significant bradycardia or atrioventricular block requiring for temporary pacemaker insertion. In this report, we present a case of trans-coronary pacing via a Rota wire to prevent bradycardia during RA in the proximal right coronary artery (RCA).

Case summary

A 72-year-old woman with a 1 month history of worsening effort angina was admitted to our hospital. Computed tomography coronary angiography disclosed significant coronary stenosis with severe calcification in proximal RCA. Coronary angiography revealed significant coronary stenosis with severe calcification in the proximal RCA. Subsequently, percutaneous coronary artery intervention was performed under the guidance of intravascular ultrasound (IVUS). The pull-back IVUS showed a circumferential calcified lesion in the proximal RCA that was treated using RA, which induced significant bradycardia requiring temporary pacemaker insertion. Immediately, trans-coronary pacing was provided via a Rota wire placed in the far distal RCA; this was used for back-up pacing during RA. Rotational atherectomy was completed by safely modifying the calcified lesion. After successful debulking of the calcified lesion, we dilated with a balloon, and a drug-eluting stent was implanted at the proximal RCA. Final IVUS and angiography showed good stent apposition and expansion. We did not observe any serious intraprocedural complications.

Discussion

Rotational atherectomy is used for plaque modification in patients with heavily calcified coronary lesions. Rotational atherectomy can induce significant bradycardia or atrioventricular block requiring for temporary pacemaker insertion via the transvenous route. This method could be an effective method to prevent bradycardia during RA.

The Wattson temporary pacing guidewire for transcatheter heart valve implantation

Transcatheter aortic valve implantation and implantation of other transcatheter heart valves, generally requires insertion of a temporary venous pacemaker. Implantation of a temporary venous pacemaker adds complexity, time and risk to the procedure. Guidewire modification to allow pacing is increasingly popular, however it requires technical expertise and provides unipolar pacing resulting in high thresholds and potential capture loss. The Wattson temporary pacing guidewire is a novel device which offers guidewire support for valve delivery and concomitant bipolar pacing. It may offer a safe and effective solution to guidewire pacing for transcatheter aortic valve implantation and other transcatheter heart valve implantations. Herein, we review the literature surrounding left ventricular guidewire pacing along with the features and clinical data of the Wattson wire.

Transcoronary pacing in an animal model : Second coated guidewire versus cutaneous patch as indifferent electrodes

BACKGROUND

Transcoronary pacing is a seldom used treatment option for unheralded bradycardias in the setting of percutaneous coronary interventions (PCI). In the present study we compared a coated guidewire inserted proximally into a coronary artery with a cutaneous patch electrode as indifferent electrodes for transcoronary pacing in a porcine model.

METHODS

Transcoronary pacing was investigated in 7 adult pigs in an animal catheterization laboratory. A standard guidewire insulated by a monorail-balloon was advanced into the periphery of a coronary artery serving as the cathode. As the indifferent anode, a special guidewire with electrical insulated by a polytetrafluoroethylene (PTFE) coating was positioned into the proximal part of the same coronary vessel. Transcoronary pacing parameters (threshold and impedance data and the magnitude of the epicardial electrogram) were compared with unipolar transcoronary pacing using a cutaneous patch electrode.

RESULTS

Transcoronary pacing was successful against both indifferent electrodes. Pacing thresholds obtained with the coated guidewire technique (1.8 ± 1.3 V) were similar to those obtained by standard unipolar transcoronary pacing with a cutaneous patch electrode (1.8 ± 1.5 V). The impedance with the additional coated guidewire was 419 ± 144 Ω and thereby slightly higher compared to 320 ± 103 Ω obtained by pacing against the patch electrode (p < 0.05). Both settings yielded comparable R‑wave amplitudes (8.0 ± 5.1 mV vs. 7.1 ± 3.6 mV).

CONCLUSIONS

A second coated guidewire is as effective as a cutaneous patch electrode when added as an indifferent electrode in transcoronary pacing. This transcoronary pacing technique could replace temporary transvenous pacing in emergency situations during PCI, especially when using the radial approach.

The double guidewire approach for transcoronary pacing in a porcine model

BACKGROUND

Transcoronary pacing is used for treatment of unheralded bradycardias in the setting of percutaneous coronary interventions (PCI).

OBJECTIVES

In the present study we introduced a new concept - the double guidewire approach - for transcoronary pacing in a porcine model.

METHODS

Transcoronary pacing was applied in 16 adult pigs under general anaesthesia in an animal catheterization laboratory. A special guidewire with electrical insulation by PTFE coating except for the distal part of the guidewire was positioned in the periphery of a coronary artery serving as the cathode. As the indifferent anode, an additional standard floppy tip guidewire was advanced into the proximal part of the same coronary vessel. The efficacy of double guidewire transcoronary pacing was assessed by measurement of threshold and impedance data and the magnitude of the epicardial electrogram compared with unipolar transcoronary pacing using a standard cutaneous patch electrode as indifferent anode.

RESULTS

Transcoronary pacing was effective in all cases. Pacing thresholds obtained with the double guidewire technique (1.5 ± 0.9 V) were similar to those obtained by standard unipolar transcoronary pacing with a cutaneous patch electrode (1.2 ± 0.7 V) and unipolar transvenous pacing against the same cutaneous patch electrode (1.5 ± 1.0 V). Bipolar transvenous pacing yielded the lowest pacing threshold at 0.8 ± 0.4 V.

CONCLUSIONS

Transcoronary pacing in the animal model with the novel "double guidewire approach" is a simple and effective pacing technique with comparable pacing thresholds obtained by standard unipolar transcoronary and transvenous pacing.

Coronary stent immobilization during angioplasty by transcoronary ventricular pacing via a guidewire

INTRODUCTION AND OBJECTIVES

In some patients, cardiac contractions cause the coronary artery segment adjacent to a stent to move in such a way that accurate stent positioning is difficult. A number of techniques have been described for immobilizing the stent at the target site by inducing periods of either asystole or tachycardia. This study shows how pulsatile motion can be controlled by means of rapid ventricular pacing via an angioplasty guidewire.

METHODS

The study involved 27 consecutive patients in whom excessive stent movement during angioplasty complicated accurate stent implantation. In these selected patients, myocardial tachycardia was induced by transcoronary ventricular pacing via an angioplasty guidewire with the aim of reducing the pulsatile motion of the stent.

RESULTS

At baseline, the median displacement was 4.08 mm (interquartile range 2.75 mm). During pacing at 100 and 150 beats per minute, the median displacement was 1.39 mm and 0.54 mm, respectively (interquartile range 1.66 mm and 0.54 mm, respectively). Transcoronary myocardial pacing was effective in 96% of cases. No complications associated with pacing were reported.

CONCLUSIONS

Transcoronary ventricular pacing via an angioplasty guidewire was an effective and safe method for achieving stent immobilization in cases where there was excessive pulsatile motion.