New and more efficient CRT-implantation technique based on the advantages of the multipolar left ventricular lead (Quartet™): A single centre comparison between conventional and new strategy

Introduction: Cardiac resynchronization therapy (CRT) is a well-established therapy in case of severe heart failure. Usually the implantation of left ventricular (LV) lead requires an occlusive venography to identify coronary sinus anatomy. Based on this information the surgeon chooses the best lateral target vein for left ventricular lead placement. The introduction of the novel multipolar LV lead (Quartet™ lead, St. Jude Medical) with its advantage of 10 different LV lead stimulation vectors enables the modification of LV lead approach. Therefore we performed an initial study in order to elucidate the possible benefits of this new approach.

Methods: In a period from October 2009 till October 2010 we prospectively included all consecutive heart failure patients requiring defibrillator CRT-systems (CRT-D) into our registry. The implantation was performed either in a conventional approach (CA) including an occlusive coronary sinus venography prior to LV lead placement or in a new approach (NA) where only a selective angiography of target coronary sinus branches was executed. Implantation time, total fluoroscopy time, volume of used contrast fluid and the number of detected target veins were noted.

Results: During the observation period 107 patients received multipolar Quartet™ leads. The implantation has been performed in 35 patients (32.7%) by conventional (CA) and in 72 (67.3%) by described new approach. Both groups had comparable baseline characteristics. The measured values are demonstrated in the table below:

Table 1:

	Conventional Approach (n = 35)	New Approach (n = 72)	P Value
Median Total implant duration, min (IQR)	105.00 (89.00 – 136.00)	89.00 (75.75 – 100.25)	p < 0.05
Median Total Fluoroscopy time, min (IQR)	19.25 (13.38 – 31.29)	13.78 (9.34 – 18.08)	p < 0.05
Median Volume of Contrast used, ml (IQR)	82.50 (45.00 – 131.25)	40.00 (25.00 – 76.25)	p < 0.05
Mean No. of Target veins visualised, (SD)	2.09 (0.78)	1.73 (0.70)	p = 0.54

Conclusions: The change of implantation technique decreases implantation and fluoroscopy time and reduces dramatically the need of contrast fluid by a moderate reduction of visualized target vessels. Therefore, we believe that demonstrated CRT implantation approach is more efficient and less wearing in standard implantation scenario compared to conventional technique. Moreover, our results suggest that occlusive coronary sinus venography is not obligate needed in standard implantation procedure.