Back to 2014 Annual Meeting Posters

Background:
Minimally invasive coronary artery bypass grafting (MICS CABG) is a safe and widely applicable procedure for coronary artery disease. We reviewed a single surgeon’s experience with MICS CABG, noting operative time, number of bypasses performed and rate of conversion to sternotomy.
Methods:
A prospectively accumulated database of 720 MICS CABG performed by one surgeon between January 2005 and December 2012 was reviewed. MICS CABG is performed through a 4-5 cm thoracotomy in the left 5th intercostal space via which harvesting of left internal thoracic artery, proximal anastomoses on the ascending aorta and distal anastomoses are done in a stepwise fashion.
Results:
A total of 700 consecutive cases were distributed into equal sized chronological 7 groups. Number of triple vessel disease referrals has increased significantly (1^st vs 5^th Group:p=0.0001; 1^st vs 6^th Group:p=0.007). Number of bypasses was significantly increased between the first 100 cases and the successive 600 patients (p <0.001). We observed significant decreased in operative time index after the first 200 cases (p <0.0001) (figure 1 and table 2).
Conclusions:
With experience in MICS CABG number of bypassed vessels increases and operative time and conversion to sternotomy decreases.

Table 1: Patient demographics, postoperative outcome and 30-day mortality
	Initial Case set	Group 1	Group 2	Group 3	Group 4	Group 5	Group 6
N	1-120	121-220	221-320	321-420	421-520	521-620	621-720
Age	62±11	64±10	62±12	64±11	66±11	67±10	65±12
Male	74(61%)	69%	82%	74%	70%	80%	71%
Diabetes	34(28%)	28%	29%	26%	35%	32%	44%
Hypertension	98(81%)	76%	84%	81%	80%	91%	90%
Chronic obstructive pulmonary disease	22(18%)	16%	16%	9%	11%	12%	16%
Peripheral vascular disease	10(8%)	11%	8%	7%	6%	8%	7%
Ejection fraction, %	40±12	40±11	42±10	43±12	43±10	44±12	48±12
Diseased Vessels
One	18(15%)	14%	14%	14%	7%	12%	4%
Two	51(43%)	33%	44%	38%	30%	17%	35%
Three	51(43%)	53%	42%	48%	63%	71%	61%
Urgent	81(68%)	70%	60%	53%	62%	55%	55%
Operative time, min	247±67	269±90	244±75	244±85	258±70	266±55	244±48
No. bypasses performed	2.2±0.8	3±1	3±1	2.6±1	3±1	3±1	2.7±1
Left internal mammary artery utilized	95%	97%	98%	99%	100%	98%	99%
Converted to sternotomy	10(8%)	3%	1%	2%	1%	0	1%
Cardiopulmonary bypass - Pump Assist	3(2%)	6%	6%	8%	11%	13%	1%
Cardiopulmonary bypass time, min	70±34	56±62	49±25	90±108	83±67	91±64	0
Perioperative blood products	0.9±1.9	1.4±3.3	0.9±2.6	1.3±2.8	0.9±1.8	1.5±1.9	0.8±1.9
Re-Operation for Bleed	4(3%)	3%	3%	3%	4%	2%	0
Atrial Fibrillation	31(26%)	21%	27%	20%	20%	23%	19%
Stroke <24 hours	1(0.8%)	1%	0	0	0	0	0
Superficial surgical site infection	0	0	0	1%	0	0	0
Length of Stay	6±3.8	6±9	6±10	5±4	6±5	5±3	6±4
Mortality-30 DAY	1(0.8%)	2%	1%	1%	1%	0	0

Table 2: The means and standard deviations of the total operative time/ number of bypass according to the chronological groups of MICS-CABG patients. (i.e. 1^st group: the first 100 MICS-CABG cases, 7^th group: last 100 MICS-CABG cases.)

	Mean	Standard deviations	P value
1st group	135.4583	43.60151	Ref
2nd group	129.8717	37.77322	0.33
3rd group	119.785	32.70317	0.0045
4th group	116.4867	36.64334	0.001
5th group	108.655	45.65881	< 0.0001
6th group	109.1658	48.64363	<0.0001
7th group	101.9097	30.45284	<0.0001

Additional analyses showed statistical significant difference in operative time was noted after the first 200 cases (between 2^nd and 3^rd group).
Figure 1: The total operative time/ number of bypass ratio according to the chronological groups of MICS-CABG patients.