Transcatheter aortic valve implantation: Current status and future perspectives

Table 1 Comparative characteristics of the Edwards SAPIEN and Corevalve ReValving System valves

Features	Edwards SAPIEN XT	Medtronic core valve
Manufacturer	Edwards Lifesciences	Medtronic
Stent	Cobalt Chromium	Nitinol
Valve leaflets	Bovine pericardium	Porcine pericardium
Implantation	Balloon-expandable	Self-expandable
Repositionable	No	Partially (prior to release)
Retrievable	No	No
Fixation	Aortic annulus	Aortic annulus and ascending aorta
Available diameters (mm)	23, 26	26, 29
Recommended annulus diameter (mm)	18-25	20-27
Delivery system diameter	18F (23) and 19F (26)	18 F
Minimum required arterial diameter (mm)	6	6
Alternative to transfemoral	Transapical	Trans-subclavian
Permanent pacemaker implantation	< 10%	25%-35%

Table 2 Clinical outcomes across the most recent published studies

	Year published	Patients	Valve	Access	Procedural success (%)	30-d mortality (%)	1-yr mortality (%)
PARTNER EU[55]	2010	61	ES	TF	91	8.1	21.3
SOURCE Registry[56]	2010	463	ES	TF	95.2	6.3	-
PARTNER cohort B[11]	2010	179	ES	TF	-	5	30.7
Rodés-Cabau et al[24]	2010	168	ES	TF	90.5	9.5	25
PARTNER cohort A[12]	2011	244	ES	TF	-	3.3	22.2
PARTNER EU[55]	2010	69	ES	TA	91	18.8	51.7
SOURCE Registry[56]	2010	575	ES	TA	92.7	10.3	-
Rodés-Cabau et al[24]1	2010	177	ES	TA	96.1	11.3	23
Wong et al[45]1	2010	60	ES	TA	98.3	18.3	-
PARTNER cohort A[12]	2011	104	ES	TA	-	3.8	29
Grube et al[43]	2008	1022	CS	TF	91.2	10.8	-
Piazza et al[57]	2008	646	CS	TF	97.2	8	-
Avanzas et al[58]	2010	108	CS	103 TF/5 TS	98.1	7.4	17.7
Tamburino et al[27]	2011	663	CS	599 TF/64 TS	98	5.4	15

¹Dr. Wong and Dr. Rodés-Cabau are from the same centre, probably patients overlapped in these two studies;

²Results referred to the third generation Corevalve ReValving System (CS) device only. ES: Edwards SAPIEN; TF: Transfemoral; TA: Transapical; TS: Trans-subclavian.

Table 3 Future valves under development

Name	Manufactured by	Country	Advantages and published experience
AorTx™	Hansen Medical	USA	Fully retrievable
Direct Flow™	Direct Flow Medical Inc	USA	Fully retrievable, inflatable fabric cuff around the valve that seals the aortic annulus. 6 patients implanted[59]
Engager™	Medtronic	USA	Specifically designed for transapical access. Easy positioning, better fixation (hooks). 30 implants in tricuspid position[53]
HLT™	Heart Leaflet Technologies	USA	”Flow-through” configuration that does not create obstruction. No need for rapid pacing
JenaValve™	JenaValve	Germany	Repositionable, clipping of the native leaflets. No need for rapid pacing. First-in-man
Lotus™	Sadra Medical / Boston Scientific	USA	Fully repositionable, self-centreing, early leaflet function before final release. First-in-man[60]
Paniagua™	Endoluminal technology Research	USA	Low profile catheter. First retrograde implantation in the world[61]
St Jude™	St Jude Medical	USA	Additional binding in the ascending aorta. Early stages. No human implants yet
ValveXchange™	ValveXchange Inc	USA	Permanent support frame and exchangeable leaflet set. Early stages. No human implants yet