A comparative cohort study of totally laparoscopic and open aortobifemoral bypass for the treatment of advanced atherosclerosis

Figures & data

Figure 1 Flow chart of the comparative cohort study. Laparoscopic aortobifemoral bypass versus open aortobifemoral bypass during the period 2005–2011.

Abbreviations: ABFB, aortobifemoral bypass; AIOD, aortoiliac occlusive disease; TASC, Trans-Atlantic Inter-Society Consensus.

Table 1 Clinical characteristics of the patients operated either with totally laparoscopic aortobifemoral bypass (LABF) or with open aortobifemoral bypass (OABF) during the period 2005–2011

Variables	LABF, N=50	OABF, N=30	Two-tailed P-value
Age in years	62 (59–67)a	62 (60–70)a	0.47
BMI	24.2 (22.8–25.7)a	25.4 (22.4–27.5)a	0.25
Hypertension	38 (76%)	23 (77%)	0.94
CHD	17 (34%)	7 (23%)	0.31
Dyslipidemia	30 (60%)	21 (70%)	0.36
Diabetes mellitus	6 (12%)	8 (27%)	0.09
Tobacco use	37 (74%)	21 (70%)	0.69
ASA 3	36 (72%)	16 (53%)	0.09
COPD	14 (28%)	4 (13%)	0.12
Prior vascular intervention/operation	22 (44%)	12 (40%)	0.58
Run-off artery stenosis/occlusion	21 (42%)	11 (37%)	0.63
Suprarenal cross-clamping	0	9 (30%)	0.001
Prior laparotomy	14 (28%)	7 (23%)	0.64

Notes:

a Median and interquartile range.

Abbreviations: ASA 3, The American Society of Anesthesiologists category 3; BMI, body mass index; CHD, coronary heart disease; COPD, chronic obstructive pulmonary disease.

Figure 2 Survival analysis.

Notes: (A) Survival freedom from composite event in the 80 patients’ cohort, operated with totally laparoscopic aortobifemoral bypass (n=50) and open aortobifemoral bypass (n=30). Median follow-up time period of 4.12 years (range from 1 day to 9.3 years). (A) Composite event. (B) Graft thrombosis. (C) Systemic complications. (D) Mortality.

Table 2 Effect of procedure on composite outcome and its components, using the patient–time model

Endpoint	LABF, N=50 (patient years)	OABF, N=30 (patient years)	RR (95% confidence interval)	Two-tailed P-value
Major outcome
Mortality	5 (300)	8 (160)	0.33 (0.08–1.15)	0.005
Graft thrombosis	3 (308)	4 (197.8)	0.48 (0.07–2.84)	0.051
Systemic complication	4 (295.8)	13 (123.5)	0.13 (0.03–0.41)	0.00001
Composite endpoint (mortality, graft thrombosis, and systemic complication)	10 (267)	19 (93.5)	0.18 (0.07–0.42)	0.00001
Secondary outcome
Operation time (minutes)	265 (250–291)	214 (183–252)		0.0003
Aorta cross-clamping time (minutes)	59.5 (51–76)	26.5 (30–95)		0.0001
Operative bleeding (mL)	400 (300–600)	1000 (600–1500)		0.0001
Hospital stay (days)	5 (4–7)	11 (8–13)		0.0002

Note: Comparison of secondary endpoints between the total laparoscopic aortobifemoral bypass (LABF) or open aortobifemoral bypass (OABF).

Abbreviation: RR, rate ratio.

Table 3 Crude effect of laparoscopic aortobifemoral bypass versus open aortobifemoral bypass

Event	Effect	HR (95% confidence interval)	P-value
Composite endpointa	Crude	0.21 (0.09–0.46)	0.0001
	Adjustedc	0.18 (0.08–0.42)	0.0001
Mortalitya	Crude	0.34 (0.11–1.04)	0.06
	Adjustedd	0.27 (0.08–0.49)	0.03
Graft thrombosisb	Crude	0.44 (0.10–1.91)	0.27
	Adjustede	0.26 (0.06–1.09)	0.06
Systemic complicationsb	Crude	0.15 (0.05–0.46)	0.001
	Adjustedf	0.14 (0.04–0.45)	0.001

Notes:

a Cox’s model for composite event and mortality;

b Cox proportional hazard model for cause-specific hazard for competing risk endpoints, graft thrombosis, and systemic complications;

c adjusted hazard ratio (HR) controlling for age and suprarenal cross-clamping (confounding effect 14.3%);

d adjusted HR for age and suprarenal cross-clamping (confounding effect 20.6%);

e adjusted HR controlling for age and suprarenal cross-clamping (confounding effect 41%);

f adjusted HR controlling for sex, ASA classification, BMI, and diabetes mellitus (confounding effect 7%), using the Cox proportional hazard model.

Abbreviations: ASA, The American Society of Anesthesiologists; BMI, body mass index.