Recently, with the results of the MIRACLE and COMPANION trials, there has been an increase in the demand for implanting cardiac resynchronization devices. One of the initial hurdles that the implanter must overcome is to access the coronary sinus through its ostium. However, in approximately 1–5% of cases, the coronary ostia may be difficult to identify. Muscle bands, bridges, and valves may prevent the operator from entering the coronary sinus and thereby finding an appropriate left ventricular lateral branch. A number of tools have been utilized to facilitate these difficult implants. We describe a case report of such a muscle band, identified by intracardiac echocardiography. Intracardiac echocardiography helped to facilitate a difficult transvenous endocardial biventricular implant (thereby obviating the need for an epicardial approach).

Figure 1

Intracardiac echocardiograph (ICE) of right atrium emptying into the coronary sinus vein. The level of the ICE transducer helped to fluoroscopically identify the level of the coronary sinus ostium.

Figure 2

A venogram of the ostium performed by using ICE and a steerable lumen electrophysiology catheter towards the ostium of the coronary sinus.

Case Report. The patient was a 40-year-old man with a severe dilated cardiomyopathy, a history of ventricular tachycardia and implantable cardioverter defibrillator, a left ventricular ejection fraction of 20 percent, and New York Heart Association class III congestive heart failure, despite optimal medical therapy. The patient has a wide QRS complex of 150 ms. The patient was referred for an upgrade of an implantable cardioverter-defibrillator to a cardiac resynchronization device (i.e. the addition of a coronary sinus/left ventricular pacing lead). The patient underwent a very difficult procedure by an experienced biventricular device implanter (greater than 50 implants), which consisted of approximately six hours of using a variety of straight and curved commercially available sheaths, and catheters with contrast injections in order to access the coronary sinus vein. The procedure was eventually aborted, even after a second operator assisted in the procedure — approximately six hours in total — without success. A recent coronary angiogram failed to demonstrate any levophase, and the patient was scheduled for a right femoral venous attempt at cannulating the coronary sinus. A 20-pole steerable catheter, which we routinely use for coronary sinus cannulation, failed to identify the coronary sinus ostium. A 9 French (Fr) introducer sheath was placed in the left femoral vein and an intracardiac echocardiography catheter (Ultra ICETM, Boston Scientific, San Jose, California) was positioned in the superior vena cava and a pullback was performed in order to identify the coronary sinus ostium. Once visualized, a 6 Fr steerable EP catheter with a central lumen (Luma-Cath, Irvine Biomedical, Irvine, California) was positioned near the ostium. Contrast was injected through the lumen in order to visualize the coronary sinus ostium (Figure 2). A 0.018´´ guidewire was then advanced into the coronary sinus, and a steerable lumen catheter was advanced deep into the coronary sinus, thereby creating a target for placing the sheath from the left subclavian vein into the coronary sinus (Figure 3). The catheter was secured in the groin and the patient was then prepped and draped for a left pectoral implant. The procedure was successfully performed using a steerable EP catheter and a long, curved sheath with a steerable EP catheter. While aiming for the target, the coronary sinus lead was placed in a lateral left ventricular branch with excellent pacing and sensing thresholds, which achieved appropriate cardiac resynchronization (Figure 4).

Figure 3

Once the coronary sinus ostium was identified, a soft guidewire was advanced into the vessel and the catheter secured deep inside the vessel. This was used as a target for the cannulation of the ostium but the left subclavian venous approach.

Figure 4

The successfully deployed left ventricular lead using the described techniques.

Discussion. This case demonstrates the utility of intracardiac echocardiography to facilitate localization of the coronary sinus ostium and thereby implantation of left ventricular leads. Previously, intracardiac echocardiography has been utilized to facilitate transseptal catheter placement and help localize critical intracardiac structures during electrophysiology studies and catheter ablations.^1–5 A search of the National Library of Medicine (Medline) failed to identify any prior case reports of intracardiac echocardiography being used to find the coronary sinus ostium and place implantable left ventricular leads. This paper highlights the advantages of intracardiac echocardiography for facilitating difficult electrophysiology procedures. Intracardiac echocardiography can help localize, and position these new leads into difficult to find coronary sinus vessels.

This article was reprinted with permission from The Journal of Invasive Cardiology 2003;15:685–686.