Total arterial revascularization with an internal thoracic artery and radial artery T graft

Coronary artery bypass grafting versus percutaneous coronary intervention in single-vessel left anterior descending artery disease: mid-term propensity matching study

Introduction

Coronary artery bypass grafting (CABG) has been considered to be the proven therapeutic choice for coronary artery disease. However, percutaneous coronary intervention (PCI) with drug-eluting stents is increasingly used for extensive coronary artery disease with contradictory results. The aim of this study is to compare immediate- and mid-term results of CABG where skeletonized internal mammary artery (IMA) was used as in situ graft versus PCI with serolimus drug eluted stents (SES) in single-vessel left anterior descending artery (LAD) disease.

Methods

In 2014-2022, 938 patients treated for isolated LAD revascularization were included in this study. Among them, there were 346 patients with CABG-IMA and 592 patients with SES-PCI. CABG-IMA patients (n = 266) were compared with SES-PCI patients (n = 266) in propensity score-matched method.Primary outcome measures were identified as all-cause mortality at 30 days and 3 years after surgery, while secondary outcome measures were length of hospital stay and the incidence of postoperative major adverse cardiovascular and cerebrovascular events (MACCE).

Results

Increased incidence for post procedural MACCE after PCI was recorded (CABG = 1.2% vs. PCI = 5.3%; p < 0.05). There was no difference in immediate-term (30 days: CABG = 1.2% vs. PCI = 1.5%; p = ns) and mid-term (3 years: CABG = 3.7% vs. PCI = 4.5%; p = ns) mortality between the groups. Patient after SES-PCI had shorter length of hospital stay (CABG = 7.7 days vs. PCI = 3.8 days; p < 0.05).

Conclusion

The results of the study indicated that CABG-IMA performed at the time of myocardial revascularization in single-vessel LAD disease is better than SES-PCI. Our conclusion is independent of traditionally accepted risk factors incorporated in the Logistic EuroSCORE II (European System for Cardiac Operative Risk Evaluation) and SYNTAX score II (Synergy Between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery Score II) and is exclusively method related.

The use of free versus in situ right internal mammary artery in coronary artery bypass grafting

INTRODUCTION

Coronary artery bypass grafting (CABG) continues to be the most commonly performed cardiac surgical procedure in the world. The use of multiarterial grafting may confer a long-term survival benefit over the use of vein grafts. However, there is a paucity of data comparing the use of in situ versus free right internal mammary artery (RIMA) in isolated CABG.

METHODS

Patients that underwent isolated CABG between 2010 and 2018 where RIMA was used in addition to a left internal mammary artery graft. Patients with prior cardiac surgery or percutaneous coronary intervention were excluded. Propensity matching was used for subanalysis. Mortality and major adverse cardiac and cerebrovascular events (MACCE) were analyzed with Kaplan-Meier survival curves and Cox multivariable regression. Heart failure-specific readmissions were assessed with cumulative incidence curves with Fine and Gray competing risk regression.

RESULTS

A total of 667 patients underwent isolated CABG. Of those, 422 had free RIMA and 245 had in situ RIMA utilized. Mortality was similar between cohorts (p = 0.199) with 5-year mortality rates of 6.6% (free) and 4.1% (in situ). MACCE was similar between cohorts, with 5-year event rates of 33.6% and 33.9% (p = 0.99). RIMA style was not a significant predictor of any outcome.

CONCLUSION

There was no difference in long-term mortality, complications, MACCE, or heart failure readmissions when comparing a contemporary cohort of patients undergoing isolated CABG utilizing RIMA as a conduit. These data may allow surgeons to consider using RIMA either as an in situ or a free conduit.

Comparison of graft patency following coronary artery bypass grafting in the left versus the right coronary artery systems: a systematic review and meta-analysis

Although coronary artery bypass grafting has been the standard of care for patients with complex coronary artery disease for over 50 years, the evolution of graft patency over time in the left versus the right coronary systems remains poorly documented. This systematic review and meta-analysis aimed to characterize the evolution of graft patency over time comparing the left (excluding left anterior descending artery) and right coronary systems, with an emphasis on the comparison of venous versus arterial grafts and symptomatic versus asymptomatic patients. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and MEDLINE from inception to August 2016. We also searched clinical trials registers and reference lists of relevant studies. We included randomized clinical trials and observational studies comparing graft patency in the left versus the right coronary systems. Our outcome was graft patency defined as a binary variable according to whether grafts were reported as patent or failed at the time of angiogram. Data collection and analysis were performed according to the methodological recommendations of the Cochrane Collaboration. From a total 2275 papers, 52 studies were included in the qualitative analysis and 48 studies (including 36 006 grafts) in the meta-analysis. There was a 3.3% significant difference between the left-sided and right-sided graft patency, and the difference appeared to increase over time. Furthermore, patency of arterial grafts was higher in the left coronary system, while venous grafts performed similarly irrespective of the coronary circulation. Symptom recurrence also seemed related to a higher failure rate in the right coronary circulation. However, the high degree of heterogeneity precluded drawing definite conclusions. This meta-analysis suggested that graft patency might be better for left-sided vessels and that this difference might be driven by the better performance of arterial grafts in the left coronary system. However, evidence currently available is limited, and further research is warranted to understand whether certain grafts achieve better patency in the right versus the left coronary circulations.

Composite Y Grafts From the Left Internal Mammary Artery: Current Considerations

The use of composite coronary artery bypass grafts from the left internal mammary artery (LIMA) has increased over the last 20 years. Total arterial revascularisation can be achieved with two arterial conduits and is associated with a reduced risk of stroke. However, the traditional coronary bypass graft configurations of the in situ LIMA and aorto-coronary saphenous vein grafts remain as the mainstay of coronary bypass surgery in most centres. Concerns regarding composite Y grafts relate to (1) the adequacy of a single inflow for all coronary bypass grafts; (2) the risk of compromising the LIMA flow to the left anterior descending coronary artery; (3) the effects of competitive flow on graft patency; and (4) the use of sequential coronary anastomoses. The evidence upon which these concerns are based will be discussed along with the evidence relating to the use of the various second conduit options.

What has happened to multiple arterial grafting in coronary artery bypass grafting surgery?

Coronary artery bypass grafting (CABG) is a well-established therapy for patients with multivessel coronary artery disease, with excellent short- and medium-term results. This is best illustrated by studies comparing percutaneous coronary interventions (PCIs) with CABG surgery, where CABG continues to offer better event-free survival. However, there has been increasing concern about the long-term patency of vein grafts utilized for CABG when compared with arterial grafts. Some have suggested that revascularization with arterial grafts rather than vein grafts may result in improved outcomes following CABG. This is particularly important when one considers that graft occlusion can result in recurrence of disabling angina, rehospitalization, reintervention and death. To date, however, multiple arterial grafts have yet to become the standard approach for patients undergoing CABG. This is best exemplified by reports from large registries suggesting that the use of multiple arterial grafting is limited to approximately 10% of all patients undergoing CABG. In this article, we will provide some of the evidence outlining the risk and benefits of multiple arterial grafting, but more importantly, begin to explore why the utilization of multiple arterial grafting does not appear to be increasing significantly.

Y grafting for coronary artery bypass: is it as good as single grafting?

PURPOSE OF REVIEW

The use of multiple arterial grafting has gained popularity in recent years due to its clinical advantages when compared with conventional CABG surgery. The purpose of the present review is to focus in particular on the safety and efficacy of composite Y grafting in coronary surgery.

RECENT FINDINGS

Several studies demonstrated mid-term and long-term benefits of total arterial myocardial revascularization when compared with conventional CABG, that is utilizing the left internal mammary artery and multiple veins. Nevertheless, there have been concerns whether it is safe to have a single inflow rather than multiple aorto-coronary grafts. There is evidence in literature that composite arterial grafting is nowadays a well established technique, and several configurations can be performed according to the specific patients' needs. Moreover, the use of Y grafting completely avoids aortic manipulation, especially when used in association with the off-pump technique.

SUMMARY

Composite Y grafting with the exclusive use of arterial conduits is a well tolerated and effective technique. The choice of the second arterial conduit should be tailored according to the specific patients' characteristics. The association of composite arterial grafting and off-pump technique allows a no-touch technique of the ascending aorta, thereby also minimizing the risk of neurological events.

Formulaic expression of composite grafts of coronary artery bypass

This is to introduce a formulaic expression of composite grafts of coronary artery bypass.

Late results of conventional versus all-arterial revascularization based on internal thoracic and radial artery grafting

BACKGROUND

Use of one or more arterial grafts to revascularize two-vessel and three-vessel coronary artery disease has been shown to improve coronary artery bypass graft surgery (CABG) survival. Yet, the presumed long-term survival benefits of all-arterial CABG have not been quantified.

METHODS

We compared propensity-adjusted 12-year survival in two contemporaneous multivessel primary CABG cohorts with all patients receiving 2 or more grafts: (1) all-arterial cohort (n = 612; 297 three-vessel disease [49%]); and (2) single internal thoracic artery (ITA) plus saphenous vein (SV) cohort (n = 4,131; 3,187 three-vessel disease [77%]).

RESULTS

Early (30-day) deaths were similar for the all-arterial and ITA/SV cohorts (8 [1.30%] versus 69 [1.67%]) whereas late mortality was substantially greater for the ITA/SV cohort (85 [13.9%] versus 1,216 [29.4%]; p < 0.0001). The risk-adjusted 12-year survival was significantly better for all-arterial (with a risk ratio [RR] = 0.60; 95% confidence interval [CI]: 0.48 to 0.75; p < 0.001), but this benefit was true only for three-vessel disease (RR = 0.58; 95% CI: 0.43 to 0.78; p < 0.001) and not for two-vessel disease (RR = 0.97; 95% CI: 0.66 to 1.43; p = 0.89). The all-arterial survival benefit was also true for varying risk subcohorts: no diabetes mellitus (RR = 0.50; 95% CI: 0.37 to 0.69), diabetes mellitus (RR = 0.77; 95% CI: 0.56 to 1.07), ejection fraction 40% or greater (RR = 0.60; 95% CI: 0.45 to 0.78), and ejection fraction less than 40% (RR = 0.62; 95% CI: 0.40 to 0.98). Lastly, the multivariate analysis indicated a strong long-term effect of completeness of revascularization, particularly for all-arterial patients, so that compared with patients with two grafts, survival was significantly better when three grafts (RR = 0.54; 95% CI: 0.33 to 0.87) or four grafts (RR = 0.40; 95% CI: 0.21 to 0.76) were completed.

CONCLUSIONS

All-arterial revascularization is associated with significantly better 12-year survival compared with the standard single ITA with saphenous vein CABG operation, in particular for triple-vessel disease patients. The completeness of revascularization of the underlying coronary disease is critical for maximizing the long-term benefits of arterial-only grafting.

Configurations and classifications of composite arterial grafts in coronary bypass surgery

The aim of this review is to present the configurations and classifications of composite arterial grafts in coronary bypass surgery. Articles were collected by tracking references cited in the literature with regard to the configurations of composite arterial grafts in coronary bypass surgery. Figures of the configurations were drawn in accordance to the schematic drawings, angiograms, photographs, table contents or written captions of the literature. According to their structural nature, composite arterial grafts can be classified as: (i) alphabetical (Y, T, I, U, K, X and H) and (ii) complex grafts (TY, loop, pi and sling grafts). According to the conduits that form the composite graft, they can be classified as: (i) definite (all standard alphabetical grafts, classic pi and sling grafts); (ii) varying [internal mammary artery (IMA) loop, modified pi graft]; and (iii) indefinite conduit graft (TY graft). According to their application in coronary artery bypass grafting (CABG), they can be divided into complete arterial revascularization for: (i) triple vessel disease (T, Y, K, X, TY, pi and sling grafts); (ii) two vessel disease (U, right Y, and two-thirds right IMA T grafts); and (iii) single vessel disease, mainly the left anterior descending artery with or without the diagonal branch (H, I, IMA loop and left IMA T grafts). According to the CABG method, they can be classified as: (i) for conventional CABG (sling graft); (ii) for minimally invasive direct coronary artery bypass (H graft); and (iii) for both conventional CABG and off-pump coronary artery bypass (T, Y, U, K, I, TY, IMA loop, and pi grafts). Standard Y and T grafts have been accepted as the common figurations of composite arterial grafts to maximum graft length for the bypass of triple vessel disease. Composite arterial grafts overcome the limited availability of arterial conduits for performing total arterial myocardial revascularization, allow a gain in conduit length, and minimize the ascending aorta manipulation.

Quality control after total arterial revascularisation: multislice computer tomography cannot replace coronary angiography

INTRODUCTION

Coronary angiography is regarded as the gold standard in evaluating graft patency, Multi-slice CT (MSCT) which enable rapid imaging of cardiac structures, including coronary arteries may be a less invasive technique. Therefore in our institution a prospective pilot study was performed combining these procedures.

PATIENTS AND METHODS

Starting from July 2004 a study was done with 13 patients. They received TAR using composite left internal thoracic artery (LITA) and left radial artery (RA) as T-graft. Intra-operative angiography was performed in these patients to confirm graft patency. Follow-up control (9-21 months) was performed with exercise Ergometry and 64 slides MSCT.

RESULT

Mean procedure time for intra-operative angiography was 13.7 +/- 7.3 min and mean fluoroscopy time was 6.2 +/- 4.6 min. In one patient, RA-marginal artery side to side anastomoses was stenosed and had to be revised. And in another, there was a kinking of the LITA and was corrected. At follow-up, exercise ergometry showed no signs of angina or ECG-changes in all patients. MSCT showed occluded radial artery grafts in two patients. In two other patients interpretation was difficult due to resolution reasons. In all patients the LITA graft was patent.

CONCLUSION

The intra-operative graft angiography can be performed in patients undergoing TAR easily. MSCT can be used for post-operative less-invasive angiography with limitations in patients with small graft/coronary diameters and arrhythmias. However, this study shows that an interdisciplinary cooperation is a new possibility toward quality control during and after TAR.

Elective vs non-elective radial artery grafts: comparing midterm results through 64-Slice computed tomography

BACKGROUND

Left internal thoracic artery to left anterior descending artery (LITA-LADA) grafting has become a fundamental part of the coronary artery bypass graft procedure (CABG). This grafting in turn has led to an increased use of other arterial conduits, of which the radial artery (RA) is most popular. Whether RA grafting can be used in the emergency patient is controversial.

METHODS

47 patients with critical stenosis (>70%) in all target vessels underwent CABG with LITA and RA grafts from 1996 to 2003. Patients were divided into elective (23 patients) and non-elective groups (24 patients) with LITA and RA grafts per patient being similar in both groups. Of these 47 patients, 5 died from non-cardiac complications and 12 were unavailable. Thus, 30 patients (71% of survivors) were studied by multidetector computed tomography. A total of 36 LITA and 64 RA grafts were studied.

RESULTS

The RA patency rate for elective and non-elective grafts were 82% (31/38) and 85% (22/26), respectively (p=0.75). The RA had a similar patency rate for all target vessels ranging from 73% to 100%. Only one patient had a redo CABG and 29 (97%) are free from angina or re-intervention. LITA-LADA had a 92% (11/12) and 100% (10/10) patency rate for elective and non-elective groups, respectively (p=0.37). The sequential LITA-diagonal-LADA in the elective group had a 50% (03/06) patency rate, which was significantly lower than the 100% (08/08) patency rate of the non-elective group (p=0.02).

CONCLUSION

Radial Artery grafts can be used in both elective and non-elective patients with excellent results.

The effect of total arterial grafting on medium-term outcomes following coronary artery bypass grafting

BACKGROUND

While it is believed that total arterial grafting (TAG) for coronary artery bypass grafting (CABG) confers improved long-term outcomes when compared to conventional grafting with left internal mammary artery and saphenous vein grafts (LIMA+SVG), to date, this has not become the standard of care. In this study, we assessed the impact of TAG on medium-term outcomes after CABG.

METHODS

Peri-operative data was prospectively collected on consecutive first-time, isolated CABG patients between 1995 and 2005. Patients were divided into two groups based on grafting strategy: TAG (all arterial grafts no saphenous veins) or LIMA+SVG. Patients who had an emergent status or underwent fewer than two distal bypasses were excluded. Medium term univariate and risk-adjusted comparisons between TAG and LIMA+SVG cases were performed.

RESULTS

A total of 4696 CABG patients were included with 1019 patients undergoing TAG (22%). Unadjusted in-hospital mortality was 1.5% for TAG patients compared to 2.0% for LIMA+SVG (p = 0.31). The mean follow-up was 4.8 +/- 2.0 years for TAG patients compared to 6.1 +/- 3.0 years for LIMA+SVG patients (p < 0.0001). At follow-up total mortality (8% vs 19%; p < 0.0001), and the incidence of readmission to hospital for cardiac reasons (29% vs 38%; p < 0.0001) were significantly lower in TAG compared to LIMA+SVG patients. However, after adjusting for clinical covariates, TAG did not emerge as a significant independent predictor of long-term mortality (HR 0.92; CI 0.71-1.18), readmission to hospital (HR 1.02; CI 0.89-1.18) or the composite outcome of mortality and readmission (HR 1.00; CI 0.88-1.15). Risk adjusted survival was better than 88% in both TAG and LIMA-SVG patients at 5 years follow-up.

CONCLUSION

Patients undergoing TAG appear to experience lower rates of medium-term all-cause mortality and readmission to hospital for any cardiac cause when compared to patients undergoing LIMA+SVG. However, after adjusting for clinical variables, this difference no longer persists suggesting that at median follow-up there are no mortality or morbidity benefit based on the choice of conduit.

Total arterial revascularization and concomitant aortic valve replacement

The safety of total arterial revascularization with a left internal thoracic artery-radial artery T-graft was evaluated in patients with at least two-vessel coronary artery disease and aortic valve stenosis requiring concomitant aortic valve replacement. From June 2001 to January 2005, 18 patients underwent aortic valve replacement and total arterial revascularization, while 101 had aortic valve replacement and conventional grafting. By matching age, sex, left ventricular ejection fraction, and number of distal anastomoses, 1:2 matched groups were generated: 15 patients with a left internal thoracic-radial artery T-graft, and 30 with left internal thoracic artery and additional vein grafts. Aortic cross clamp and cardiopulmonary bypass times were similar in both groups. There were no significant differences in postoperative data between the groups. Early mortality was 0% in the T-graft group and 2% in those with conventional grafts. Follow-up ranged from 2 to 50 months. Event-free survival was 100% in the T-graft group and 90% in the conventional graft group. Total arterial grafting with a left internal thoracic-radial artery T-graft can be performed in selected patients with aortic valve stenosis requiring simultaneous aortic valve replacement.

Forearm Muscle Necrosis After Radial Artery Harvesting for Coronary Artery Bypass Surgery

Donor site complications after radial artery harvesting for coronary revascularization have been primarily wound related and parasthesias. Forearm muscle compartment syndrome has only been reported once. A patient underwent successful coronary revascularization with a radial artery graft; however his forearm extensor muscles necrosed, possibly from a missed compartment syndrome, and he required tendon transfers to provide finger and wrist extension.

Harvesting radial artery and neurologic complications

BACKGROUND

Determination of the incidence, mechanisms, and diagnosis of hand complications after radial artery (RA) harvesting in coronary surgery (CABG).

METHODS

The study group (RA group) includes 54 patients who underwent RA harvesting in CABG operation. The control group (noRA group) consists of 131 patients who underwent CABG without the use of RA graft. The average follow-up time was 16.36 +/- 5.13 months. The patients were examined clinically, (a) for motor function abnormalities associated with radial and median nerve damage and (b) for sensory abnormalities, and the function of radial nerve was determined by eliciting the brachioradialis reflex. They answered in a formal scripted questionnaire to elicit symptoms and clinical points attributable to nerve damage during RA harvest, such as hand weakness, thumb weakness, sensation abnormalities on the back and on the palm side of the forearm, hand numbness, hand-reversible paresis or forearm infection postoperatively, and any other upper limb abnormality.

RESULTS

Of the patients in the RA group, 34.09% reported left-hand abnormality after operation. On the other hand, in the noRA group left-hand abnormality was reported in 18.68% of patients. In the RA group sensation abnormality was reported in 34.09% of patients and thumb weakness alone was reported in 6.82% of patients. There was a statistically significant difference between the two groups. Low EuroSCORE was the predicting factor for motor abnormalities.

CONCLUSIONS

More knowledge has been added about the neurologic complications after RA harvesting lately. We demonstrated the rate of motor and sensory abnormality, the potential mechanisms of these complications caused by surgical trauma or devascularization, and any predictive factors of complications. Optimal surgical techniques to avoid the damage of the responsible nerves are recommended.

Total Arterial Revascularization is Safe: Multicenter Ten-Year Analysis of 71,470 Coronary Procedures

BACKGROUND

The purpose of this study was to assess the use of arterial revascularization and to compare the in-hospital mortality with other CABG grafting strategies.

METHODS

A total of 71,470 CABG patients (1992-2001) in 27 centers in the United Kingdom were studied. The proportion of patients with arterial revascularization was compared. In-hospital mortality was compared for various grafting strategies: all-arterial (n = 5,401), all non-all-arterial patients (n = 66,069), one artery any number of veins (n = 49,801). The groups were compared for in-hospital mortality using multivariate logistic regression to assess the independent effect of the grafting strategies on mortality; logistic EuroSCORE-predicted mortality was compared to actual mortality, and all arterial and one artery and veins patients were compared with propensity score analysis.

RESULTS

There was a significant increase in the proportion of all-arterial patients over time (3.2% to 11.7%, p < 0.001) with evidence of variability across centers. Crude mortality for all-arterial patients was 2% vs 3% for all non-all-arterial patients (p < 0.001). In multivariate analysis, all-arterial was associated with a slight but insignificant increase in in-hospital mortality (odds ratio [OR] 1.13; [95% confidence interval {CI} 0.86-1.48], p = 0.36). There was a trend toward higher mortality in the all-arterial group when compared with the one artery and veins group (OR 1.19 [95% CI 0.91-1.56], p = 0.10). The one artery and veins group was the only group where actual mortality was significantly lower than predicted by EuroSCORE (p < 0.001). In propensity analysis the mortality was 1.51% for one artery and veins and 1.74% of all-arterial patients (p = 0.56).

CONCLUSIONS

The use of arterial grafting has increased over time, varies by center, and appears to be safe in terms of in-hospital mortality.

Perioperative and clinical-angiographic late outcome of total arterial myocardial revascularization according to different composite original graft techniques

Total arterial myocardial revascularization (TAMR) is advisable because of the excellent long-term patency of arterial conduits. We present early and midterm outcomes of five different surgical configurations for TAMR. Between January 1998 and May 2004, 112 patients (aged 56.5 +/- 4.5 years, 20% female) with three-vessel disease underwent TAMR. The internal mammary arteries (IMAs) were harvested in a sketelonized fashion. The surgical techniques for TAMR consisted in Y or T composite grafts (n = 88, 78%) constructed between the in situ right IMA (RIMA) and the free left IMA (LIMA) graft (n = 58) or the radial artery (n = 30) (RA) in three different configurations. The other techniques consisted in T- and inverted T-graft (n = 24, 22%) constructed between the RA conduit and the free LIMA graft in two different configurations. The mean follow-up time was 40 +/- 23 months. Postoperative angiographic control was performed in 76/111 (70%) patients. Overall, 472 arterial anastomoses (average 4.2 per patient) were performed. One (0.9%) patient, undergoing the inverted T-graft technique, died on postoperative day 2. Another patient (0.9%), undergoing the lambda-graft technique using both IMAs and RA, suffered a new myocardial infarction probably due to RA conduit vasospasm. One week after surgery, after the transthoracic echocardiographic Doppler with adenosine provocative test, the coronary flow reserve (CFR) at the LIMA and RIMA main stems were 2 +/- 0.4 and 2.4 +/- 0.3, respectively. At 12-month follow-up, after adenosine provocative test, the CFRs at the LIMA and RIMA stems were significantly higher than the values at 1 week after surgery within the same group; (LIMA)CFR (1 week) 2.4 +/- 0.3 (12 months) vs 2 +/- 04 (1 week), P = 0.002; (RIMA)CFR 2.58 +/- 0.4 vs 2.4 +/- 0.3, P = 0.001. The CFR at the RIMA main stem was higher in all measurements within the same group than in the LIMA main stem, but not significantly. In one patient undergoing the lambda-graft technique using both IMAs, the RIMA was found to have a string sign. Postoperative angiography in 50 patients showed that the patency rate for the LIMA was 100%, for the RIMA 97.3%, and for the RA 96.7%. Angiography at 3-year follow-up in 76 patients documented excellent patency rates of the LIMA (97.4%), RIMA (95%), and RA (87%). Survival at 7 years was 92.5%, event-free survival 89.3%, and freedom from angina 94%. Total arterial myocardial revascularization using different surgical configurations is safe and effective. The use of composite arterial grafts provides excellent clinical and angiographic results, with a low rate of angina recurrence and late cardiac events. These configurations allow for complete arterial revascularization.

Total arterial revascularisation in left ventricular dysfunction

The feasibility and safety of total arterial coronary revascularization with 2 arterial conduits in patients with impaired left ventricular function was evaluated. Data were prospectively collected on all patients with multiple vessel discase and moderately or severely impaired left ventricular function, who underwent coronary surgery with the intention of total arterial revascularization with 2 conduits between March 1995 and August 2002. One hundred and seventy-nine patients were included in the study. Acute coronary insufficiency was present in 3 patients and 43 had unstable angina. Severe left ventricular impairment was present in 29 patients. There were 17 redo operations including 3 redo-redo procedures. Eighty-two percent of patients had a Y graft configuration from the left internal mammary artery (right internal mammary artery 40.8%, radial artery 33.5%, other 7.8%). The perioperative mortality was 2.2%, myocardial infarction 1.7% and stroke 0.6%. Total arterial revascularization in patients with ischaemic left ventricular dysfunction can be safely performed with 2 arterial conduits. The radial artery provides conduit length greater than the right internal mammary artery and allows full revascularization despite left ventricular dilatation.

Mid-Term Results of Radial and Mammary Arteries as the Conduits of Choice for Complete Arterial Revascularization in Elective and Nonelective Coronary Bypass Surgery

OBJECTIVE

The aim of this study is to evaluate the mid-results of the use of the radial artery alongside the internal mammary artery for complete arterial revascularization in elective and nonelective coronary bypass graft surgery.

METHODS

All patients undergoing coronary artery surgery alone over a 3-year period with disease of more than one coronary artery were considered for complete arterial revascularization. Preoperatively, all patients had an Allen's test on the dominant arm and a cutoff point of 10 seconds was used. These patients were initially followed in the outpatient clinic after 6 weeks and then further followed up with the help of a mailed questionnaire. The incidence of recurrent angina and reangiogram was obtained and selected patients were further interviewed and examined in the outpatient department.

RESULTS

Over a 3-year period, 291 patients underwent total arterial revascularization using the radial and internal mammary arteries alone in Y-graft configuration. The mean age of the study population was 62.4 +/- 8.8 years, with a male to female ratio of 221 to 70. Elective surgery was performed in 230 patients (79.4%), with nonelective procedures comprising a total of 61 patients (20.6%). The mean number of distal anastomoses was 2.9 +/- 0.9. There were four perioperative mortalities (1.37%) and 43 patients (14.7%) developed low cardiac output syndrome, requiring inotropes with or without intra-aortic balloon pump. Forty patients (13.7%) developed postoperative supraventricular arrhythmias. There was no incidence of hand ischemia or wound complications. After a mean follow-up period of 35.4 +/- 6.3 months of 220 patients (75%), there was one further death and 24 patients required readmissions for cardiac-related causes. Ten patients had reangiogram for angina of which one patient had a blocked radial artery graft and two patients underwent angioplasty to their native coronary arteries. The patients' angina score was currently 0.5 +/- 1.0 versus 2.6 +/- 1.4 preoperatively.

CONCLUSION

Total arterial revascularization with the internal mammary and radial artery is associated with a low rate of perioperative complications and mortality and can be safely used in both elective and nonelective bypass graft surgery with excellent clinical results.

Role of Radial Artery Graft in Coronary Artery Bypass Grafting

The use of the radial artery (RA) as a coronary artery bypass graft has assumed a revival and thus a multitude of issues have arisen surrounding the routine and widespread use of this conduit in myocardial revascularization. There has been no uniformity regarding harvest techniques, assessment of the adequacy of hand collateral circulation, antispasm protocols, selection of target vessels, and the site of proximal anastomosis. It is widely believed and practiced that the RA should be harvested as a pedicle graft and preferably be used to bypass critically stenosed (>70% stenosis) coronary arteries. It is used either as a free graft with proximal anastomosis to the ascending aorta or as a composite arterial graft along with the left or right internal thoracic artery. The patency of RA grafts depends on the severity of the target coronary artery stenosis and target artery location rather than its use as an aortocoronary conduit or composite graft. In this article, we reviewed the current knowledge regarding the use of RA grafts as a coronary bypass conduit in an attempt to suggest a few acceptable strategies concerning the above issues in a given clinical scenario.

Coronary revascularization with the left internal thoracic artery and radial artery: comparison of short-term clinical evolution between elective and emergency surgery

BACKGROUND

Left internal thoracic artery-to left anterior descending artery grafting has become a fundamental part of coronary artery bypass grafting. This grafting has led to increased use of other arterial conduits, of which the radial artery is most popular. Whether radial grafting can be used in the emergency patient is not known. This study compares the short-term clinical evolution between elective vs emergency coronary artery bypass grafting surgery with left internal thoracic artery and radial artery.

METHODS

A retrospective study of 47 patients who underwent elective or emergency coronary artery bypass grafting from 1996 to 2003. All patients had coronary stenosis>70% in all target vessels. Only the left internal thoracic artery and radial artery were used as grafts. Patients were divided into elective group (23 patients) and emergency group (24 patients). Emergency criteria were unstable angina and/or critical coronary stenosis with high risk for acute myocardial infarction. Groups were similar for age and number of diseased vessels.

RESULTS

The mean number of left internal thoracic artery grafts per patient in the elective and emergency groups were respectively 1.17 and 1.38 (P=.17). The mean number of radial artery grafts per patient in the elective and emergency groups was respectively 2.26 and 2.08 (P=.48). The 30-day mortality was 0. There was no postoperative cardiogenic shock. The elective group had 1 acute myocardial infarction (4.4%) postoperatively, and emergency group had 5 (20.8%). A nonsignificant trend towards acute myocardial infarction was noted in the emergency group (P=.18). Intensive care unit and postoperative stay were similar in both groups.

CONCLUSION

Coronary artery bypass grafting using left internal thoracic artery and radial artery accomplishing complete revascularization can be performed in emergency patients with results similar to those for elective patients.

Outcome assessment of hand function after radial artery harvesting for coronary artery bypass

The radial artery has gained widespread acceptance as a conduit for coronary artery bypass. Advantages include minimal donor site discomfort, ease of handling, excellent early patency rates, and the possibility of freedom from late conduit atherosclerosis. Although most series describe minimal morbidity, a significant incidence of radial sensory neuropathy and isolated instances of hand claudication and ischemia have been reported. We performed an outcome study utilizing the Short Form-36, the Upper Limb-Disabilities of Arm, Shoulder and Hand, and a modified self-administered hand diagram to compare 288 patients undergoing coronary artery bypass utilizing the radial artery with a control group of 174 patients undergoing coronary artery bypass without the radial artery. The data were analyzed by the t test for continuous variables and the chi-square test for categorical variables, and subsequently a multivariate regression model was constructed. No patients developed hand claudication or ischemia. Although there was an incidence of radial sensory neuropathy of 9.9% associated with radial artery harvest, it was not significantly higher than the incidence in the control group (5.2%, p =.16). Intrinsic patient factors such as obesity, age, diabetes, and peripheral vascular disease were the principal determinants of overall health and quality of life issues.

Total arterial revascularization with composite skeletonized gastroepiploic artery graft in off-pump coronary artery bypass grafting

BACKGROUND

Total arterial revascularization in coronary artery bypass grafting has recently become of great interest to many surgeons. At the same time, off-pump coronary bypass grafting has also become a popular procedure because of its low morbidity and mortality. Here we report our recent series of off-pump coronary bypass grafting performed with a grafting technique we developed by using the skeletonized gastroepiploic artery and the radial artery composite graft to achieve total arterial revascularization.

METHODS

From September 2000 to April 2003, 98 patients underwent total arterial revascularization with the skeletonized gastroepiploic artery and radial artery composite graft on the beating heart. We used the gastroepiploic artery graft of choice in patients with a right coronary artery lesion. When multiple grafting was required in inferior, posterolateral, or lateral ventricular walls and the gastroepiploic artery graft was too short to cover these areas, we used the composite grafting technique.

RESULTS

There were no in-hospital deaths and there was no severe morbidity among the study patients. Postoperative angiography showed graft occlusion at the anastomosis site between the gastroepiploic and radial arteries. The patency rate of the gastroepiploic arterial composite graft was 98.3% (118/120 distal anastomoses).

CONCLUSIONS

A composite graft with the skeletonized gastroepiploic artery and the radial artery ensured sufficient caliber size and length for myocardial revascularization on inferior, posterolateral, and lateral ventricular walls. This composite graft can be used safely and effectively even in off-pump coronary bypass surgery with excellent early clinical and angiographic outcome in selected patients, although longer follow-up periods are necessary to draw definitive conclusions.

Improved Survival With Radial Artery Versus Vein Conduits in Coronary Bypass Surgery With Left Internal Thoracic Artery to Left Anterior Descending Artery Grafting

Background— Given its proven survival benefit, left internal thoracic artery to left anterior descending (LITA-LAD) grafting has become a fundamental part of CABG. This grafting also led to increased use of other arterial conduits, of which the radial artery is most popular. Whether radial grafting improves survival beyond that achieved by LITA-LAD alone is not known.

Methods and Results— We compared 6-year outcomes in propensity-matched CABG-LITA-LAD patients (925 each) divided into those with ≥1 radial grafts and those with vein-only grafting. Matched patients had essentially identical demographics, comorbidities, coronary disease, and operative data. Perioperative outcomes, including death (radial, 11 [1.2%]; vein, 10 [1.1%]), were similar for the 2 groups. Cumulative 0- to 6-year survival was better for radial patients (risk ratio, 0.675), particularly after 3 years ( P <0.03). Six-year survival in vein (86.8%) and radial (92.1%) patients indicated 67% greater overall vein mortality. Incidence rates of radial and vein repeated catheterization (190 of 925 [20.5%] versus 199 of 925 [21.5%]) and revascularization (8.8% versus 8.5%) were similar. Angiography data in restudied symptomatic patients showed a trend for greater radial patency. Vein failure (66 of 161 [41%]) was significantly worse than radial failure (46 of 157 [29.3%]) in patients receiving both types of grafts ( P =0.039).

Conclusions— Using radial as a second arterial conduit in CABG-LITA-LAD as opposed to vein grafting improves long-term outcomes as a result of decreased late deaths, especially after the third postoperative year.

Left internal thoracic artery-radial artery composite grafts as the technique of choice for myocardial revascularization in elderly patients: a prospective randomized evaluation

OBJECTIVES

The technique of choice for myocardial revascularization in elderly patients remains a debated issue. We evaluated the potential advantages of the use of left internal thoracic artery-radial artery composite grafts compared with conventional coronary artery bypass grafts in elderly patients.

METHODS

We prospectively enrolled 160 patients aged more than 70 years scheduled to undergo isolated myocardial revascularization. Patients were assigned at random to group 1, 80 patients undergoing total arterial revascularization (left internal thoracic artery on left anterior descending coronary artery plus radial artery), or group 2, 80 patients undergoing standard coronary artery bypass graft surgery (left internal thoracic artery on left anterior descending coronary artery plus saphenous veins). The radial artery was used in all cases as a composite Y-graft.

RESULTS

Preoperative characteristics and risk factors (EuroSCORE: group 1 = 7.9 vs group 2 = 8.1), number of grafted coronary vessels (group 1 = 2.4 vs group 2 = 2.5), aortic crossclamping time (group 1 = 37 +/- 7 minutes vs group 2 = 38 +/- 7 minutes), ventilation time (group 1 = 22 +/- 12 hours vs group 2 = 23 +/- 11 hours), intensive care unit stay (group 1 = 39 +/- 10 hours vs group 2 = 40 +/- 9 hours), and hospital mortality (group 1 = 3.8% vs group 2 = 5%) were comparable between the groups. Comparison between the 2 groups in terms of early postoperative complications showed a higher incidence of cerebrovascular accidents in group 2 (group 1 = 0 patients vs group 2 = 4 patients, 5%). At a mean follow-up of 16 +/- 3 months, patients in group 1 showed superior clinical results with a lower incidence of graft occlusion (group 1 = 2 vs group 2 = 11; P =.06) and angina recurrence (group 1 = 2 patients vs group 2 = 12 patients; P =.03). Multivariate analysis identified saphenous vein grafts as independent predictors for graft occlusion and angina recurrence.

CONCLUSIONS

Left internal thoracic artery-radial artery composite grafts proved to be a safe procedure in elderly patients. It improved the clinical outcome, providing a significantly higher graft patency rate and a lower incidence of late cardiac events.

The Influence of Calcium Channel Antagonists on Isolated Human Distal Radial Arteries

A comparison was made between the efficacies and potencies of calcium channel antagonists on contractions induced by 5-hydroxytryptamine, norepinephrine, or high-potassium buffer in isolated human distal radial arteries. Also, the impact of removal of extracellular calcium ions on contractions induced by 5-hydroxytryptamine or norepinephrine was assessed. Isometric contractions were induced by agonists, and relaxant responses to calcium channel antagonists, nifedipine, diltiazem, verapamil, or mibefradil were examined. 5-hydroxytryptamine-induced contractions when compared with norepinephrine or high-potassium induced contractions were significantly more sensitive to inhibition by nifedipine (pIC50 = 7.53 +/- 0.15; 6.78 +/- 0.12; 6.6 +/- 0.22, respectively, mean +/- SEM). Diltiazem was more effective in producing relaxations when contractions were elicited with 5-hydroxytryptamine (pIC50 = 6.48 +/- 0.84) or norepinephrine (pIC50 = 6.20 +/- 0.21) than with high potassium (pIC50 = 5.43 +/- 0.10). Verapamil was more effective at relaxing arteries contracted with 5-hydroxytryptamine (pIC50 = 6.09 +/- 0.19) or norepinephrine (pIC50 = 6.00 +/- 0.17) than with high potassium (pIC50 = 5.60 +/- 0.16). Mibefradil was not very effective in producing relaxations. The studies revealed that removal of extracellular calcium significantly attenuated contractions produced by 5-hydroxytryptamine (-67.7 +/- 6.3%) and norepinephrine (-89 +/- 1.5%). In conclusion, our data indicates that nifedipine was the most effective drug in producing relaxations; also, contractions produced by 5-hydroxytryptamine and norepinephrine were found to be critically dependent on the presence of extracellular calcium.

Total arterial myocardial revascularization with composite grafts improves results of coronary surgery in elderly: a prospective randomized comparison with conventional coronary artery bypass surgery

BACKGROUND

Total arterial myocardial revascularization with composite grafts proved to enhance the long-term benefits of coronary surgery. We assessed the hypothesis that full arterial revascularization (FAR) may improve clinical outcome even in elderly and at short term.

METHODS AND RESULTS

A prospective randomized study was designed to compare FAR with conventional coronary artery bypass grafting (CABG) surgery [left interval thoracic artery (LITA) on left anterior descending (LAD) plus additional saphenous vein grafts] with the following end points: early and late death, graft occlusion, reintervention, angina recurrence, and acute myocardial infarction (AMI). We enrolled 200 consecutive patients >70 years of age; population was equally divided at random in Group 1 (G1, FAR) and Group 2 (G2, Conventional). The groups resulted comparable with respect to all preoperative continuous and discrete variables and risk factors (Euroscore: G1=8.4 versus G2=8.1). No differences between G1 versus G2 were observed in terms of postoperative complications (perioperative AMI:2% versus 3%), mean intensive care unit (ICU) (hours: 39+/-11 versus 40+/-9) and hospital stay (days: 6+/-2 versus 7+/-3) nor were there any differences in hospital mortality(G1=5% versus G2=4%). At the mean follow-up of 14+/-5 months the incidence of angina recurrence was 3% in G1 versus 12% in G2. Angiographic controls of grafts showed a superior graft patency rate of all the arterial grafts when compared with saphenous vein grafts. Conventional CABG surgery was identified as incremental risk factor for angina recurrence and as predictor for graft occlusion.

CONCLUSIONS

Total arterial myocardial revascularization improved clinical outcome of patients undergoing coronary surgery in the elderly, whereas saphenous vein grafts negatively affected patient prognosis in terms of graft patency and freedom from late cardiac events.

Safety and usefulness of composite grafts for total arterial myocardial revascularization: a prospective randomized evaluation

OBJECTIVES

To evaluate the results of total arterial revascularization with composite grafts compared with the results of conventional coronary surgery, we enrolled 200 consecutive patient undergoing myocardial revascularization.

METHODS

Patients were randomly assigned to 2 groups of 100 patients each: group 1 underwent total arterial revascularization, and group 2 received left internal thoracic artery on left anterior descending artery grafts plus additional saphenous vein grafts. The groups were comparable in terms of continuous and discrete variables and preoperative risk factors.

RESULTS

There were no differences between group 1 and group 2 in terms of the number of grafted vessels (mean, 2.8 vs 2.9, respectively), crossclamping time (mean, 38 +/- 7 vs 40 +/- 6 min, respectively), intensive care unit stay (mean, 25 +/- 8 vs 24 +/- 7 hours, respectively), and hospital mortality (1% in both groups) nor were there any differences in postoperative complications. At the mean follow-up of 12 +/- 4 months, patients receiving total arterial revascularization (group 1) showed a better outcome in terms of angina recurrence (group 1 vs group 2: 2 vs 13 patients, P =.007), need of percutaneous transluminal coronary angioplasty reintervention (group 1 vs group 2: 0 vs 8 patients, P =.0012), and actuarial freedom from cardiac events (group 1 vs group 2: 96% vs 67%, P =.006). Angiography carried out in 72% in group 1 and in 68% in group 2 demonstrated a patency rate of 99% of saphenous vein grafts in group 1 and 89% of saphenous grafts in group 2.

CONCLUSIONS

Total myocardial revascularization with composite arterial grafts provided superior clinical results and improved patient outcome, even in the short term to midterm. Arterial conduit-related benefits were clearly evident with respect to recurrence of angina and a higher graft patency rate.

[Surgical revascularization of the myocardium]

It has been 45 years ago when Longmire (1958.) used internal thoracic artery (ITA) for the first time in coronary artery bypass surgery (CABG). In this review, we are presenting novel surgical approaches in CABG surgery. We have also been summarized the best of knowledge, up to date, regarding histology, pharmacology and pathophysiology of conduits (VSM, ITA and alternative venous and arterial grafts) which have been used in CABG surgery, as well as factors influence on its short and long-term patency.

Comparative study of functional responses and morphometric state of distal radial arteries in male and female

BACKGROUND

Differences can exist in terms of physiology and morphology of blood vessels on the basis of gender. Radial artery is now considered to be the second choice for coronary artery bypass grafting. However, there is a lack of comparative studies on the function and morphometery of radial arteries in female and male patients.

METHODS

Radial arteries from 9 female and 9 male patients undergoing coronary artery bypass grafting were used to compare the effects of vasoconstrictors, noradrenaline and 5-hydroxytryptamine, as well as the influence of endothelium-dependent (with methacholine) and endothelium-independent (with sodium nitroprusside) relaxations. Furthermore, morphomteric measurements of smooth muscle thickness, lumen perimeter, lumen area, and intima area (including plaque) of distal radial arteries from female and male patients were also made.

RESULTS

Radial arteries from female patients when compared to male patients were significantly more sensitive to the actions of noradrenaline, and somewhat more sensitive towards the actions of 5-hydroxytryptamine. However, no significant differences were found between the relaxant effects of methacholine in radial arteries of female and male patients. In contrast, radial arteries from female patients when compared to male patients were significantly less sensitive to the relaxant effects of sodium nitroprusside. Morphometric measurements of blood vessels from female and male patients revealed that vessels obtained from female patients had a smaller lumen area and perimeter than vessels from male patients. In contrast, there were no significant differences between tunica intima area (including plaque area) or smooth muscle thickness in radial arteries of female patients when compared to male patients. However, the radial arteries from female patients had a significantly greater ratio of tunica intima area (including plaque) to lumen area when compared with radial arteries from male patients.

CONCLUSIONS

Differences exist between the functional behavior and morphometery of radial arteries of female and male patients. It is possible that postbypass, radial artery graft may show different characteristics in female versus male patients.

Use of radial artery graft reduces the morbidity of coronary artery bypass graft surgery in patients aged 65 years and older

BACKGROUND

The use of the radial artery graft in patients aged 65 years and older could prevent the occurrence of leg wound infection, which is known to increase the morbidity of coronary artery bypass grafting surgery.

METHODS

We reviewed, retrospectively, 261 patients aged 65 years and older (age range 65 to 93 years), who underwent coronary artery bypass grafting surgery between February 1998 and August 2001. All the patients received at least one radial artery graft in addition to either a left internal thoracic artery, right internal thoracic artery, or saphenous vein graft as required. Saphenous vein grafts were used in 141 (54.1%) patients (group 1), and these were compared to 120 (45.9%) patients (group 2) who received only arterial conduits. Angiography was performed on 26 consecutive patients. The aim of the study was to review the clinical and angiographic outcomes in this population.

RESULTS

The mean number of distal anastomoses performed was 2.98. Mean global operating time was 204 minutes. This time dropped to 201 minutes in group 1 versus 231 minutes in group 2; p = 0.009. Sixteen (11.3%) patients receiving saphenous vein grafts had leg wound infection whereas only 1 (0.3%) patient of the global population had a forearm infection. The mean global hospital stay was 9.81 days; this duration increased to 13 days when leg wound infection occurred versus 9.1 days when infection did not occur; p = 0.008. Twenty-six (10%) patients underwent an early angiographic study. Twenty-four (92.3%) radial artery grafts were patent.

CONCLUSIONS

The routine use of radial artery grafts in patients aged 65 years and older is feasible, safe, and does not increase mortality, morbidity, or the complexity of coronary artery bypass grafting surgery.

Revascularization of the lateral wall: long-term angiographic and clinical results of radial artery versus right internal thoracic artery grafting

OBJECTIVE

We sought to evaluate whether the radial artery provides the same results as the right internal thoracic artery in lateral wall revascularization in the long term.

METHODS

From January 1992 to September 1996, 288 patients had myocardial revascularization with the left internal thoracic artery anastomosed to the left anterior descending coronary artery. The lateral wall was grafted with the radial artery in 139 patients (group A) and with the right internal thoracic artery in 149 patients (group B). Groups were different only because of older age and a higher incidence of patients requiring urgent treatment in group A. Y grafting was used in 86.4% of patients in group A and in 34.8% of patients in group B (P < .001). Anastomoses per patient were similar in both groups (3.2 +/- 0.8 vs 3.2 +/- 0.9, P = 1.000).

RESULTS

Thirty-day mortality was similar (2.1% vs 2.0%, P = .722). There were 15 late deaths in group A versus 11 in group B (P = .418). Cause of death was cardiac related in 6 patients in group A versus 7 in group B. Late redo or percutaneous transluminal coronary angioplasty was performed in 3 patients in group A and in 1 patient in group B (P = 0.538). Eight-year survival was 86.7% +/- 2.9% in group A versus 89.6% +/- 2.8% in group B (P = .477); event-free survival was 84.2% +/- 3.2% versus 88.9% +/- 2.9%, respectively (P = .430). The patency rate within 30 days was 99.1% in group A (105/106 left internal thoracic artery plus radial artery anastomoses) versus 100% in group B (52/52 bilateral internal thoracic artery anastomoses; P = .715). After a mean of 35 +/- 28 months, the patency rate was 99.0% in group A (100/101 left internal thoracic artery plus radial artery anastomoses) and 100% in group B (33/33 bilateral internal thoracic artery anastomoses, P = .560).

CONCLUSION

In the long-term, lateral wall grafting with the radial artery provides the same clinical and angiographic results as right internal thoracic artery grafting.

Effect of target stenosis and location on radial artery graft patency

OBJECTIVE

The purpose of this study was to evaluate the effect of target vessel characteristics on radial artery patency when used as a composite T graft.

METHODS

Between October 1993 and March 2001, 1022 patients underwent coronary bypass with the internal thoracic artery-radial artery composite T graft. Of these, angiography has been performed on 109 patients at a mean 27.1 months (range, 2-70 months) postoperatively for symptoms of ischemia. By means of Cox proportional hazard models, the relationships between anastomotic patency and target vessel location, proximal stenosis, target diameter, and quality were assessed.

RESULTS

A total of 231 radial artery anastomoses were evaluated. The mean stenosis for patent anastomoses was 82% compared with 71% for occluded anastomoses (P <.001). Anastomotic patency for targets with moderate stenosis (< or = 70%) was worse than that for vessels with critical stenosis (> or = 90%; relative risk, 1.7; 95% confidence interval, 1.3-2.2; P <.001). Patency for targets of the right coronary artery was statistically inferior to that for targets of the left anterior descending artery (relative risk, 1.8; 95% confidence interval, 1.2-2.9; P =.01) and bordered on significance versus that for the circumflex artery distribution (relative risk, 1.6; 95% confidence interval, 1.0-2.8; P =.06). When directed toward critically stenosed targets of the left anterior descending or circumflex arteries, radial artery patency was not statistically different that that of the internal thoracic artery (P =.19).

CONCLUSION

Radial artery patency is sensitive to both target location and proximal target stenosis. Selective use of the radial artery to targets of the left anterior descending and circumflex distributions remains encouraging. Radial artery grafts to targets of the right coronary artery or those with moderate stenosis appear to be at particularly high risk of failure.

The radial artery in coronary surgery: a 5-year experience--clinical and angiographic results

BACKGROUND

The radial artery (RA) has been used extensively by us as a way of reducing the use of the saphenous vein. It has been hoped that the RA will maintain greater late patency than the saphenous vein. We evaluated our initial 5-year experience with the RA in coronary surgery.

METHODS

We studied 6,646 consecutive patients who had a single RA (4,872), or bilateral RA (1,774), as coronary grafts, from June 1995 to June 2000. Angiograms were performed mostly in symptomatic patients, or as part of a research project in asymptomatic patients.

RESULTS

The patients' mean age was 65.1 years; 23% had diabetes, 14% had unstable angina, and 42% had prior myocardial infarction. An average of 3.3 grafts per patient were performed, 87% from arterial conduit. Conduits used were RA (8,420), left internal thoracic artery (6,296), and right internal thoracic artery (1,076). Operative mortality occurred in 58 (0.9%) patients, stroke in 92 (1.4%), deep sternal infection in 97 (1.4%), reoperation for hemorrhage in 56 (0.9%), and myocardial infarction in 52 (0.8%). Peak mean postoperative creatine kinase MB (CKMB) was 16.5 IU/L. Two patients developed fingertip ischemia. Postoperative angiographic RA patency was 90.2% (333 of 369 distal anastomoses).

CONCLUSIONS

Good early clinical and angiographic results can be achieved by using the RA in coronary surgery.

Midterm results of complete arterial revascularization in more than 1,000 patients using an internal thoracic artery/radial artery T graft

OBJECTIVE

To report the authors' 7-year experience with the internal thoracic artery/radial artery (ITA/RA) T graft as the only conduits for myocardial revascularization in two- and three-vessel disease.

SUMMARY BACKGROUND DATA

One and two arterial conduits provide increasing survival benefit for coronary grafting and reduce the need for reintervention. Exclusive use of arterial conduits may provide further benefit.

METHODS

From October 1993 to November 2000, 1,020 patients underwent complete arterial revascularization with the ITA/RA T graft. The authors focus on the 909 having initial bypass, with a mean age of 60 and 20% age 70 or older. The incidence of triple-vessel disease was 73%, female gender 28%, diabetes mellitus 27%, peripheral vascular disease 11%, cerebrovascular disease 10%, and chronic obstructive pulmonary disease 6%; ejection fraction was less than 35% in 11%. Perioperative data were collected prospectively. Follow-up information was obtained at a mean of 35.4 months (range 1-88) and was 95% complete.

RESULTS

There were seven (0.08%) deaths within 30 days of surgery. The incidence of perioperative infarction was 3.3%, low cardiac output 2.7%, stroke 2.2%, reoperation for bleeding 3.8%, and deep sternal infection 0.8%. The actuarial survival rate was 90% at 5 years, freedom from infarction was 94%, freedom from catheterization was 83%, and freedom from reintervention (angioplasty or reoperation) was 93%.

CONCLUSION

The ITA/RA T graft for complete arterial revascularization is associated with a low rate of perioperative death and complications and 5-year survival and freedom from reintervention values consistent with other revascularization strategies.

Radial artery for myocardial revascularization: long-term clinical and angiographic results

BACKGROUND

To evaluate the long-term clinical and angiographic results of the radial artery (RA) as a graft in coronary artery bypass surgery.

METHODS

One hundred sixty-four patients had a RA graft from July 1992 to July 1994. In 128 (group A) the RA was connected end to side (115) or end to end (13) to the left internal mammary artery. In 36 (group B) the proximal anastomosis was on the ascending aorta.

RESULTS

Early mortality was 1.8% (group A 1.6% and group B 2.8%). Eight-year survival was 83.2%+/-3.2% (group A 82.1%+/-3.8% and group B 86.7%+/-6.2%, p = not significant [NS]), and event free survival was 80.1%+/-3.5% (group A 79.9%+/-4.4% and group B 80.2%+/-7.3%, p = NS). Sixty-one patients (37.2%) had an early angiography within 90 days from the operation. Patency rate of RA distal anastomoses were 98.9% (88 of 89), 98.7% in group A (77 of 78), 100% in group B (11 of 11; p = NS). After a mean of 48+/-27 months (6 to 96), 72 patients (51.1% of the survivors) had a new angiography. Patency rate of RA distal anastomoses was 95.6% (87 of 91), 93.8% in group A (61 of 65) and 100% in group B (26 of 26; p = NS). All the intermediate RA-LIMA anastomoses were patent at the early and late control. Patency rate for RA and IMAs was similar both early (88 of 89 versus 82 of 82; p = NS) and after 48+/-27 months (87 of 91 versus 93 of 93; p = NS).

CONCLUSIONS

Long-term clinical results after RA grafting are satisfying. Angiographic patency rate, both early and after 48 months, is higher than 90% and is similar to that obtained with internal mammary arteries. The site of the proximal anastomosis does not influence early and late patency.

Occurrence of myocardial ischemia immediately after coronary revascularization using radial arterial conduits

OBJECTIVE

To assess the incidence of myocardial ischemia in patients receiving radial arterial and left internal thoracic arterial conduits (RA+LITA) during the postrevascularization period.

DESIGN

Nonrandomized observational sequential cohort.

SETTING

University hospital.

PARTICIPANTS

Thirty adult patients, scheduled for elective coronary artery bypass graft surgery with RA+LITA, compared with 30 patients who received saphenous vein graft and left internal thoracic arterial conduits.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Myocardial ischemic episodes were defined as reversible ST-segment depressions or elevations >or=1 mm and >or=2 mm at J +60 msec and lasting >or=1 minute using 2-channel Holter monitoring. During the post-cardiopulmonary bypass period, a significantly higher number of patients with >or=2 mm ischemic episodes (21.7%; p = 0.015) and higher number of >or=2 mm ischemic episodes per hour (0.19 +/- 0.4 episodes/hr; p = 0.03) were observed in the radial artery group versus the comparison group (0% of patients and 0 episodes/hr). During the postoperative period (24 hours), a significantly longer duration of >or=2 mm ischemic episodes was observed in the radial artery group (24 +/- 33 minutes v 8.4 +/- 21 minutes; p = 0.046). Radial artery graft, preoperative calcium antagonists, and pulmonary arterial mean pressure were independent predictors of the duration and area under the ST-segment curve of >or=2 mm ischemic episodes during the postoperative period.

CONCLUSION

There is an association between the use of the radial artery graft and the incidence and severity of >or=2 mm postrevascularization ischemic episodes.

Vasoreactivity of arterial grafts in the patient with diabetes mellitus: investigations on internal thoracic artery and radial artery conduits

OBJECTIVE

Arterial revascularization with either internal thoracic artery (ITA) or radial artery (RA) appears to be particularly attractive in diabetic patients. Previous investigations have shown that endothelial dysfunction and artherosclerosis are seen more often in these patients. The aim of this study was to compare the vasoreactive properties of ITA and RA grafts in diabetic and non-diabetic patients.

METHODS

Arterial rings were harvested from 57 patients who underwent complete arterial revascularization. The patients were divided into a non-diabetic group (I: n = 30) and patients with diabetes mellitus (II: n = 27). Arterial rings of the ITA (I: n = 30; II: n = 27) and RA (I: n = 28; II: n = 19) were mounted on a strain gauge in oxygenated, normothermic Krebs's--Henseleit solution at optimal resting tension. With KCL (80 mM) serving as the control, assessment of force of contraction (norepinephrine), endothelium-dependent relaxation (acetylcholine) and smooth muscle-dependent relaxation (glyceroltrinitrate) were obtained.

RESULTS

After KCL, the RA showed a trend to lower maximum contraction forces in diabetics (I: 76 +/- 25 mN; II: 69 +/- 29 mN), which was pronounced in patients with diabetes of more than 10 years duration (55 +/- 23 mN; P = 0.1). Maximum contraction force of the ITA was similar in both groups (I: 41 +/- 20 mN; II: 34 +/- 19 mN) and not influenced by the duration of diabetes. The two groups showed no significant differences of the relative vasoconstriction after norepinephrine in RA (I: 53 +/- 18%; II: 61 +/- 19%) and ITA rings (I: 70 +/- 23%; II: 69 +/- 25%). Also, endothelium-dependent relaxation with acetylcholine in RA (I: 53 +/- 14%; II: 57 +/- 16%) and ITA rings (I: 42 +/- 17%; II: 44 +/- 20%), and smooth muscle relaxation with glyceroltrinitrate of RA (I: 72 +/- 8%; II: 73 +/- 12%) and ITA rings (I: 64 +/- 12%; II: 58 +/- 20%) was comparable in both groups. No influence of duration of the diabetic disease was noted.

CONCLUSIONS

Although RA rings of patients with a long duration of diabetes have decreased maximum contraction forces, their relative vasoconstriction after norepinephrine, endothelium-dependent relaxation and smooth muscle relaxation was similar to non-diabetic patients. We thus conclude that the RA is an adequate arterial conduit in the patient with diabetes mellitus.

Extended use of radial artery with Y-graft technique for complete arterial revascularization

One of the biggest problems encountered during complete arterial revascularization is difficulty obtaining sufficient graft length to perform multiple distal anastomoses. We describe a technique of dividing the radial artery during harvest and forming one or more composite Y-grafts to allow end-to-side rather than sequential anastomoses without substantially decreasing usable conduit length. This approach has merit and may be helpful in some patients who require complex arterial grafting.

Arm complications after radial artery procurement for coronary bypass operation

BACKGROUND

Radial arteries are being used frequently for coronary artery bypass conduits, and surgeons are appropriately concerned about the risks of ischemia, infection, and neurologic dysfunction of the "donor" arm. We present our record of donor site complications, with emphasis on the safety of radial usage in patients older than 65 years of age.

METHODS

A total of 343 radial arteries were removed from 217 patients, aged 37 to 83 years. Forty-nine (23%) of the patients were women; 126 of the radial arteries were from patients aged 65 years or older. Four patients died. In the remaining 213 patients, 338 donor arms were examined for at least 6 weeks postoperatively for evidence of infection, ischemia, hematoma, seroma, or paresthesia.

RESULTS

No donor arms developed symptoms of 'ischemia or motor dysfunction. Two of 338 (0.6%) arms developed hematomas requiring operative drainage. Relatively minor complications of stitch abscesses, skin dehiscence, superficial infection, and small hematomas or seromas affected another 14 arms (4.1%). Cutaneous paresthesias in the radial distribution of the lateral antebrachial cutaneous nerve or superficial branch of the radial nerve were noted postoperatively in 36 arms (10.7%). The risk of any arm complication occurring was 13% in the 65 and older group and 17% in those less than 65 years old (p = NS).

CONCLUSIONS

The risk of a major arm complication from radial artery harvesting for coronary bypass is low, even in patients of advanced age.

Radial artery graft inflow from the undetached, unharvested RIMA: a method to avoid proximal anastomosis to the aorta in CABG surgery

Performing the proximal anastomosis of a free arterial graft to the ascending aorta is problematic, especially if the wall of the aorta is calcified or thickened. We describe a method, which makes it possible to avoid this procedure.

A review of 1,582 consecutive Octopus off-pump coronary bypass patients

BACKGROUND

Off-pump coronary bypass may provide a safer form of surgical revascularization by avoiding the unwanted complications of cardiopulmonary bypass, particularly in the increasingly complex patients being referred for operation. This study reviews the entire experience of the Medtronic Octopus System (Medtronic, Minneapolis, MN) for beating heart bypass from 7 surgeons. Demographics, operative procedures, early outcomes, and trends in usage were examined.

METHODS

Patients were selected for off-pump procedures by the individual surgeons. Data were entered prospectively into locally maintained databases and then collected for collation and analysis.

RESULTS

A total of 1,582 consecutive Octopus patients were entered, representing the entire Octopus experience of each surgeon. Proportions of off-pump procedures relative to standard bypass increased over time, as did the percentage of patients receiving three or more grafts, 24.6% in 1997 and 55.9% in 1999. A total of 3,653 anastomoses were performed, 1,905 to the left anterior descending system, 837 to the circumflex distribution, and 911 to the right coronary territory. Morbidity was low. Few patients required conversion to cardiopulmonary bypass (2.6%; 0.2% urgently). Permanent stroke occurred in 0.6% and myocardial infarction in 1.2%. Operative mortality was 1%.

CONCLUSIONS

Octopus off-pump bypass was demonstrated to be a safe procedure with widening applicability. With experience surgeons tend to apply the system to increasing proportions of their patients and are able to revascularize all coronary territories.

Nitroglycerin is preferable to diltiazem for prevention of coronary bypass conduit spasm

BACKGROUND

Diltiazem is widely used to prevent radial artery spasm after coronary bypass grafting (CABG). However, recent in vitro and in vivo studies have shown that nitroglycerin is a superior conduit vasodilator compared to diltiazem. A clinical comparison of these agents in patients undergoing CABG has not been previously performed.

METHODS

One hundred sixty-one consecutive patients undergoing isolated CABG with the radial artery were prospectively randomized to 24-hour intravenous infusion of nitroglycerin or diltiazem followed by 6-month treatment with a daily dose of isosorbide mononitrate (n = 84) or diltiazem CD (n = 77). Analyses were performed on "intention-to-treat" basis.

RESULTS

Crossovers because of low cardiac output, complete heart block, or sinus bradycardia occurred in 5 patients in the diltiazem group and none in the nitroglycerin group (p = 0.05). Operative mortality (nitroglycerin, 1.2% versus diltiazem, 1.3%), major morbidity (14% versus 16%), perioperative myocardial infarction (1.2% versus 0%), peak serum creatinine phosphokinase MB fraction levels (27 versus 21 U), intensive care unit stay (34+/-19 versus 38+/-30 hours) and total hospital length of stay (4.7+/-1.4 versus 4.7+/-1.3 days) were similar (p = not significant for all). Cardiac pacing was required more often in the diltiazem group (28% versus 13%, p = 0.01). Follow-up longer than 2 months was available in 145 patients (90%). Follow-up mortality (nitroglycerin, 1.2%; diltiazem, 1.3%), myocardial infarction (6%, versus 5%), and reintervention (8% versus 6%) rates and average angina class (1.3+/-0.7 versus 1.1+/-0.4) were similar (p = not significant for all). Thallium stress test obtained in 117 patients showed abnormal perfusion in the radial artery territory in only 4 patients (3%), 2 in each group (p = not significant). Treatment with diltiazem was more costly ($16,340 versus $1,096).

CONCLUSIONS

Nitroglycerin is preferable to diltiazem for prevention of conduit spasm. Nitroglycerin is safe, effective, better tolerated, and less costly than diltiazem, and therefore, should be the agent of choice.

Surgical management of heart failure

Surgical therapy for congestive heart failure can offer gratifying results in selected elderly patients. Several trials have shown a survival advantage for surgical revascularization compared with medical therapy in the treatment of ischemic cardiomyopathy. Aortic valve replacement is highly effective in treating elderly patients with heart failure caused by severe aortic stenosis, and stentless aortic valves seem to provide a survival advantage in elderly patients with low-gradient aortic stenosis. Mitral valve repair with or without coronary revascularization has been used successfully in patients with severe mitral regurgitation. Transplantation is a viable but rarely used option for elderly patients with congestive heart failure. Totally implantable ventricular assist devices are an exciting new option for elderly patients with congestive heart failure who are not heart transplantation candidates.

Multiple arterial grafts and survival

Limitations in the long-term patency of saphenous veins for bypass grafts have encouraged interest in the use of arterial conduits. The positive effect of an internal thoracic artery graft on survival has been accepted for more than a decade, but it has proven difficult to show additional benefit from additional arterial conduits; this is probably due to multiple factors, including inappropriate choice of target vessels, short follow-up, and inadequate numbers of patients. Recently, however, the positive effect of a second arterial graft was confirmed. It will probably be difficult to show a survival benefit from a third or fourth arterial graft, but we believe that complete arterial revascularization will result in improved long-term freedom from reintervention. Interest in arterial conduits for coronary artery bypass was primarily limited to the left internal thoracic artery until the mid-1980s, when enthusiasm for the use of bilateral internal thoracic arteries grew. More recently, the gastroepiploic artery, the inferior epigastric artery, and especially the radial artery have all found advocates. However, the original conduit--and the standard against which all others are compared--is the greater saphenous vein.