Double-balloon technique for retrograde venous ethanol ablation of ventricular arrhythmias in the absence of suitable intramural veins

Abstract

Background: Venous ethanol infusion via an occlusive balloon has been used as a bailout approach to treat ablation-refractory ventricular arrhythmias (VAs). Unfavorable venous anatomy (lack of intramural veins at the targeted site or collateral vein-ethanol shunting) limits its efficacy. Blocking collateral flow with a second balloon may optimize myocardial ethanol delivery.

Objective: The purpose of this study was to validate the "double-balloon" approach to enhance ethanol delivery in cases of unfavorable venous anatomy.

Methods: Eight patients referred after failed ablations (3 left ventricular [LV] summit, 5 scar-related ventricular tachycardia) underwent endocardial mapping and additional radiofrequency ablation without VA resolution. Coronary veins were mapped using a multipolar catheter or wire, and selective venograms were obtained. The double balloon was used when (1) distal collateral branches shunted flow away from the targeted region; (2) the target vein had optimal signals only proximally; or (3) a large vein was targeted that had multiple branches for a large area of interest.

Results: Acute successful ethanol infusion myocardial delivery and resolution of VA was accomplished using the posterolateral LV veins (n = 2 patients, 3 procedures), lateral LV vein (n = 1), apical anterior interventricular vein (AIV; n = 1), middle cardiac vein (n = 1), and septal branches of the AIV (n = 3). At median follow-up of 313.5 days, 2 patients experienced recurrence.

Conclusion: The double-balloon technique can enhance ethanol delivery to target isolated vein segments, block collateral flow, or target extensive areas, and can expand the utility of venous ethanol for treatment of VAs.

Keywords: Angioplasty balloon; Catheter ablation; Coronary vein; Ethanol; Ventricular arrhythmia.

Figure 1

Sequential double-balloon technique in a lateral left ventricular (LV) vein. A: LV map showing a low-voltage area in the lateral wall. The lateral vein lies on the epicardial aspect of the scar. B: Venogram of the lateral LV vein showing collateral flow to a posterolateral vein. C: Cannulation with a decapolar catheter (vein geometry included in the 3-dimensional map in A). D: Signals from the distal decapolar electrodes are in late diastole. E, F: Miniaturized octapolar catheter advanced further into the lateral vein. A late potential (asterisk) is recorded from the distal electrodes. G: Concealed entrainment from the distal octapolar electrodes, with postpacing interval identical to the ventricular tachycardia (VT) cycle length and a mid-diastolic signal (asterisk). H, I: Post-ethanol subendocardial echogenicity on intracardiac echocardiogram. J–M: Balloon 1 was used to infuse ethanol, while balloon 2 was used to occlude the vein distally. Four sequential balloon positionings were used, from distal (J) to proximal (M). VT became uninducible.

Figure 2

Sequential double-balloon ethanol infusion technique in a posterolateral left ventricular vein. A: Endocardial map of a large inferior scar. B, C: Coronary vein geometry (obtained with the decapolar catheter shown in C) showing a large posterolateral vein (B) overlying the endocardial scar. D: Concealed entrainment from the distal decapolar electrodes in the posterolateral vein, with postpacing interval identical to the ventricular tachycardia (VT) cycle length and a mid-diastolic signal. E: Selective venogram of the posterolateral vein. F: Two angioplasty wires and 2 balloons were advanced in the vein. G–I: Sequential balloon positioning, inflation, and ethanol infusion (via balloon 1) all along the posterolateral vein. VT became uninducible. J: Intracardiac echocardiogram showing echogenicity after ethanol infusion.

Figure 3

Repeated ethanol infusion in a posterolateral left ventricular vein. A: Endocardial scar map showing a posterolateral vein overlying the scar. B: Unipolar wire signals from the posterolateral vein showing mid-diastolic potentials. C: Venogram showing a large posterolateral vein that communicates with the middle cardiac vein (MCV). D: The posterolateral vein was cannulated with 2 balloons, one positioned distal in the vein to prevent flow into the MCV and the other used to deliver ethanol from the proximal part of the vein. The patient did well for 15 months, but ventricular tachycardia (VT) recurred. Repeat procedure showed similar VT, but the posterolateral vein was no longer accessible from the coronary sinus (CS). E: The MCV was cannulated with a sheath, and 2 wires were advanced via collaterals retrogradely into the posterolateral vein, all the way into its takeoff close to the CS. Two balloons were advanced in the posterolateral vein, one to occlude flow (balloon 2) and the other to infuse ethanol (balloon 1). F1–F4: The 2 balloons were sequentially positioned from close to the CS (F1) all the way to the connection of the posterolateral vein with the MCV (F4), with infusion of ethanol in each location, resulting in resolution of VT. PL = posterolateral branch.

Figure 4

Double-balloon ethanol infusion in the middle cardiac vein (MCV). A: Endocardial map showing an inferoseptal scar. The MCV is overlying the septal edge of the scar. B: Activation map and 12-lead electrocardiogram of the ventricular tachycardia (VT). C: Decapolar catheter in the MCV with signal in proximal electrodes preceding the QRS in VT. E: Balloon occlusion venogram showing a large MCV with communication with other ventricular veins (not shown). F: To prevent ethanol shunting, a second balloon (balloon 2) was advanced and positioned distal to the occlusion balloon (balloon 1). Both were inflated, and ethanol was delivered via balloon 1. G–J: The distal balloon (balloon 2) was sequentially positioned at more distal locations in the MCV. VT became uninducible.

Figure 5

Double-balloon technique for ethanol infusion in the anterior interventricular vein (AIV). A: Scar maps of the epicardial surface (left), endocardial surface (middle), and location of the duodecapolar catheter in the AIV relative to the scar (right). B: Fluoroscopic anteroposterior view of the duodecapolar catheter in the AIV. C: Pacing from the apical scar reproduces QRS morphology of the ventricular tachycardia (VT). D: AIV venogram showing AIV to middle cardiac vein (MCV) collateral flow. E–G: Two balloons were inserted in the AIV, one for ethanol infusion (balloon 1) and one for prevention of flow into MCV (balloon 2). Repeated injections led to increased staining of the myocardium. H–K: Consecutive balloon repositioning for ethanol delivery in more proximal locations of the AIV. VT became uninducible.

Figure 6

Double-balloon technique to prevent collateral flow from septal to annular vein. A: Initial coronary sinus (CS) venogram showing a large left ventricular annular (LVA) vein, but the electrodes from the junction of the great cardiac vein (GCV) with the anterior interventricular vein (AIV) showed the best signals. B: Venogram via a left internal mammary artery catheter showing a large septal vein at the GCV–AIV junction, with extensive collateral flow to the LVA. C: Unipolar wire signal from the septal vein (wire 1) showed the best signals, preceding the QRS by 28 ms. A second wire was inserted into the LVA vein (wire 2). D: Two angioplasty balloons were inserted over their respective wires. E: Balloon 1 was positioned in the septal vein, where the best signal had been recorded, while balloon 2 was inserted in the LVA vein to block collateral flow. F: Inflation of balloon 1. G: After inflation of balloon 2, contrast injection in the septal vein via balloon 1 led to myocardial staining in the targeted location without collateral flow. This led to elimination of the extrasystoles. H: Final CS venogram.

Figure 7

Double-balloon technique for ethanol infusion in the left ventricular summit annular (LVA) vein. A: Coronary sinus venogram. B: Wire and balloon in the LVA vein via a left internal mammary artery (LIMA) catheter. C: Wire location where best signal was recorded, preceding the QRS by 30 ms (shown in K). The wire signals were not as early more distal or more proximal in the LVA vein. D, E: LVA venograms showing large septal branches in the left anterior oblique (D) and right anterior oblique (E) views. F: A second wire was advanced outside the LIMA catheter, along with a second balloon (balloon 2). G–I: Balloon 2 was inflated to occlude the septal branch in several positionings. Ethanol led to elimination of ectopic beats (L), but radiofrequency energy was used to reinforce ablation via the retroaortic approach, guided by the ethanol-targeted location (J).