Table 1. Numbers of institutions and surgeries classified according to the number of mitral valve surgeries performed in 5 years.

No. of operations	No. of institutions	MVR					MVP
		All MVR	MVR with CCP		MVR with PMA		All MVP	MVP with PMA		MVP with PMR
		No.	No.	% of MVR	No.	% of MVR	No.	No.	% of MVP	No.	% of MVP
1–9	173	286	192	67.1	10	3.5	456	55	12.1	66	14.5
10–19	51	223	129	57.8	1	0.4	494	32	6.5	44	8.9
20–29	17	137	66	48.2	0	0.0	278	11	4.0	31	11.2
30–39	4	57	18	31.6	0	0.0	89	4	4.5	8	9.0
40–49	4	104	27	26.0	0	0.0	75	7	9.3	5	6.7
100–	1	79	11	13.9	6	7.6	21	0	0.0	0	0.0
Total	250	886	443	50.0	17	1.9	1413	109	7.7	154	10.9

CCP: complete chordal preservation; MVP: mitral valvuloplasty; MVR: mitral valve replacement; PMA: papillary muscle approximation; PMR: papillary muscle relocation