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Naik et al. Vessel Plus 2018;2:38 I http://dx.doi.org/10.20517/2574-1209.2018.62 Page 5 of 10
late post-operative period 64.7% of grafts (22 out of 34 grafts in 29 patients) had occlusive intimal changes.
[39]
On the other hand, later in the early 90’s, Acar et al. demonstrated a 93.5% patency rate at 9 month follow-
[40]
up concluding that the RA was still a reasonable alternative to complement IMA. Ikeda et al. found the
patency rates of RA graft to be 91% (24 out 26 grafts), which was comparable to ITA graft patency rate of
[41]
97% (139 out 143 grafts) in the mid post-operative period (27 ± 10 months). Subsequently, Desai et al. also
found that RA grafts were less likely to develop occlusion at one year when compared to saphenous venous
[42]
grafts. RA grafts were found to have a higher patency rate at 5 year follow up when compared to SVG .
[43]
Angiographic studies have demonstrated a patency rate of 80%-90% at 7-10 year follow-up . A more recent
study reported an 84.4% patency rate at 20 years with a probability of graft failure at a similar time to LITA
[44]
(19.0% ± 0.2% for LITA vs. 25.0% ± 0.2% for the RA) .
Moreover, a large patient-level meta-analysis, involving 1,036 patients from 6 trials, comparing RA with
saphenous vein grafts showed a significant reduction in the incidence of adverse cardiac events like
[9]
myocardial infarction, repeat revascularization, and death from cardiac causes with the use of the RA .

Vasospasm was one of the major reasons which lead to a significant degree of reluctance in the use of
the RA as a graft conduit in CABG procedures soon after its introduction. These concerns were related
to the pronounced muscular profile of the RA wall as opposed to the more elastic wall of the ITA. Peri-
[45]
operative arterial spasm is reported at 0.43% in all CABG surgeries, and He et al. have suggested this
to be an underestimate owing to the chance of mild spasms going unreported. For this reason, a number
of pharmacology prophylaxis protocols aimed at avoiding vasospasm have been developed . Treatment
[46]
includes the use of calcium channel blockers with or without long-acting nitrates in the postoperative
management of these patients or during surgery as per Reyes et al. . Chanda et al. recommend a
[46]
[48]
[47]
combination of a calcium channel blocker like nifedipine, diltiazem, or verapamil with nitroglycerine for
prevention of spasm. Organic nitrates like nitroglycerine have a short half-life but have a faster onset of action
as compared to calcium channel blockers like nifedipine, verapamil, etc. These drugs are usually started
immediately post operatively and continued for the first postoperative year. However, biological studies have
demonstrated a progressive remodeling towards a more elastomuscular phenotype after implantation of the
[50]
[49]
RA as a graft , and clinical reports deny a benefit from antispastic pharmacological therapy .
COMPARISON OF OUTCOMES BETWEEN ERAH AND ORAH
Harvesting technique may have an impact on postoperative outcomes and surgical complications. In early
[51]
experiences in the late 90’s, Royse et al. reported that post-operative numbness and paresthesia of the hand
were a commonly observed complication although there was a 98.9% resolution within 3-6 months after
surgery. Neurological complications such as sensory loss occurred in 1.6%-18.1%, while motor complications
such as diminished thumb strength were observed in 5.5% of patients in other large series [51-53] .

After the introduction of endoscopic harvesting, the incidence of these complications significantly decreased.
[54]
In an early prospective study from Patel et al. comparing ERAH with ORAH, major neurological
complication restricting motor function post-operatively (8% vs. 1% patients at 1 month, P < 0.05), wound
erythema, ecchymosis, mild numbness, or tingling were found to be significantly increased when using open
approaches [Table 1].

More recently, the results of a propensity-matched study showed significantly lower hand ischemia (open
7.3% vs. endoscopic 0%, P = 0.007), by performing a modified Allen test prior to graft selection to confirm
good collateral blood flow to the hand, and wound infection rate in the ERAH group, as well as better minor
neurological outcomes (open 19.5% vs. endoscopic 3.6%, P < 0.001). Interestingly, freedom from cardiac-
related mortality (open 96.3% ± 2.1% vs. endoscopic 98.1% ± 1.8%, P = 0.448) as well as survival free from
major cardiac and cerebrovascular adverse events (open 93.9% ± 2.6% vs. endoscopic 93% ± 3.4%, P = 0.996)