Gopichand Mannam

Reduction of sternal wound infections in diabetic patients undergoing off-pump coronary artery bypass surgery and using modified pedicle bilateral internal thoracic artery harvest technique

OBJECTIVE We compared sternal wound infections between diabetic patients undergoing off-pump coronary artery bypass surgery using bilateral internal thoracic artery grafting or single internal thoracic artery grafting and nondiabetic patients receiving bilateral internal thoracic artery or single internal thoracic artery grafting using a modified pedicled harvest technique of internal thoracic artery. METHODS This retrospective study was conducted to analyze the data from 3072 patients who underwent primary coronary artery bypass surgery using an off-pump technique from August 2004 to October 2010. Of the 1211 diabetic patients, 181 received bilateral internal thoracic artery grafts (group 1) and 1030 received single internal thoracic artery grafts (group 2). Of the 1861 nondiabetic patients, 161 received bilateral internal thoracic artery grafts (group 3) and 1700 received single internal thoracic artery grafts (group 4). The incidence of postoperative sternal wound infections in diabetic patients who received bilateral internal thoracic artery grafting was compared with the incidence in other groups (group 2, 3, and 4). A modified technique of pedicled harvesting of the internal thoracic artery was done in patients receiving bilateral internal thoracic artery grafting, and a standard pedicled harvest was used in patients receiving single internal thoracic artery grafts. RESULTS No significant differences were present in the preoperative variables among the groups. The observed rate of superficial sternal wound infections in groups 1, 2, 3, and 4 was 1.1% (2 patients), 1.65% (17 patients), 1.86% (3 patients), and 1.65% (28 patients), respectively (P=.9941). Deep sternal infections were observed in 1 (0.55%), 5 (0.48%), 1 (0.62%), and 14 patients (0.82%) in groups 1 through 4, respectively (P=.8380). Multivariate analysis showed that bilateral internal thoracic artery harvesting (P=.889), diabetes mellitus (P=.96), and patient age were not predictors of sternal wound infection. CONCLUSIONS The results of the present study show that there is no increase in the incidence of sternal wound infections in diabetic patients undergoing coronary artery bypass surgery with bilateral internal thoracic artery grafting by using a modified pedicle bilateral internal thoracic artery harvesting technique with sparing of the communicating bifurcation of internal thoracic artery to the chest wall and preservation of pericardiacophrenic artery branch.

Extrafascially harvested radial artery in CABG: technique of harvest, complications, and mid-term angiographic patency.

Abstract  Background: The initial use of radial artery (RA) for myocardial revascularization was abandoned due to high incidence of early occlusion. The revival of radial artery graft use was attributable to the improved harvesting techniques as well as the introduction of antispasm prophylaxis by calcium channel blockers. Various techniques of harvesting RA have been described and extrafascial harvest is one of the techniques to minimize trauma during harvest. The immediate arm complications and mid‐term angiographic patency of the radial artery grafts harvested using extrafascial no‐touch technique and used as a conduit for myocardial revascularization were not documented well in the literature. Methods: Between January 1997 and February 2003, 385 patients were operated for coronary artery bypass grafting using radial artery graft as one of the conduits. We used extrafascial no‐touch technique and a coagulation current cautery at a strength of 10 to 15 W to control the bleeding during the blunt dissection of the radial artery. The complications related to the radial artery harvest were prospectively recorded and analyzed. This conduit was used as a free graft in 272 patients, left internal mammary artery and radial artery Y graft in 61 patients, Right internal mammary artery, and radial artery composite in situ graft in 52 patients. The radial artery donor arm in these patients was evaluated for complications. Angiographic evaluation of the radial artery graft was carried out randomly in 51 patients and angiography was done after an interval of 6 to 72 months (mean 29.55 ± 21.77 months). Results: In two patients, although the preoperative Allen test was negative, the radial artery was not harvested after completion of the dissection and was left in situ because the pulse could not be felt in the radial artery distal to the clamp after trial occlusion of the mid part of RA. The arm complications noticed were cutaneous parasthesias in 9 patients (2.33%), which subsided in 4 weeks, stitch abscess and superficial wound infection in 4 patients (1.03%), hematoma/seroma treated with drainage in outpatient department in 3 patients (0.78%), and wound infection requiring open drainage in an operating room in one patient (0.76%). Angiographically radial artery was patent in 48 of 51 patients (94.11%). Conclusions: The extrafascial technique of radial artery harvest is safe and an easily reproducible method with minimal arm complications and good mid‐term clinical and angiographic results. The mid‐term angiographic patency rates of RA harvested using this technique are comparable to that of the published results of intrafascially harvested radial artery grafts and left internal mammary artery grafts.

Right internal mammary artery and radial artery composite in situ pedicle graft in coronary artery bypass grafting

BACKGROUND The use of two internal mammary artery grafts in coronary artery bypass grafting has been associated with decreased risks of death, reoperation, and angioplasty. However, bilateral internal mammary artery takedown is associated with higher incidence of sternal wound infection, particularly in people with diabetes and in elderly and obese patients. This study was conducted to explore the feasibility of using right internal mammary artery (RIMA) and radial artery (RA) as a composite graft while preserving the distal two thirds of the RIMA to leave the sternal blood supply intact. METHODS Eighteen patients underwent coronary artery bypass grafting using proximal RIMA and RA composite graft as one of the bypass conduits. The distal two thirds of the RIMA was left intact to preserve sternal blood supply. The graft-free flows of the RIMA and RA composite graft and of the left internal mammary artery graft and the length of the composite graft had been measured. The graft patency and the flow in the distal part of the unharvested RIMA was evaluated postoperatively 2 weeks after the procedure. In 6 of these patients the graft patency was evaluated by selective angiography. RESULTS There was no hospital mortality or incidence of perioperative myocardial infarction. None of the patients needed intraaortic balloon pump support postoperatively. There was no sternal wound infection. The vessels grafted were distal right coronary artery (n = 7), posterior descending artery (n = 8), obtuse marginal branches (n = 3), and posterolateral ventricular branch (n = 1); 1 patient received the composite graft as a sequential graft to the posterior descending artery and posterolateral left ventricular branches. The mean graft-free flow of the RIMA and RA composite graft was 98.06 +/- 16.93 mL/min compared to left internal mammary artery flows of 55.80 +/- 8.99 mL/min. All 16 patients who had a good echo window showed patent grafts when evaluated by two-dimensional echocardiography and color Doppler echocardiography. All of the 6 patients in whom the angiogram was repeated postoperatively showed patent RIMA and RA grafts. CONCLUSIONS Myocardial revascularization using proximal RIMA and RA in situ pedicle graft was safe in patients with diabetes and in obese and chronic obstructive pulmonary disease patients. This graft was useful to revascularize posterior descending artery, posterolateral ventricular branches of right coronary artery, and obtuse marginal branches where a left internal mammary artery and RA composite graft cannot be used because of technical reasons. Its usage was not associated with sternal wound infection.

Internal thoracic artery: Anatomical and biological characteristics revisited

The left internal thoracic artery has become the conduit of choice for coronary artery bypass grafting, due to its superior patency rates at 10 or more years with little or no evidence of atherosclerotic changes. Recent evidence indicates that a second internal thoracic artery graft provides improved results relative to overall survival and major cardiac and cerebrovascular event-free survival, and reduces the need for repeat revascularization. However, the routine use of bilateral internal thoracic arteries is limited due to a perceived higher incidence of deep sternal wound infection. The surgical anatomy, collateral blood supply to the sternum, and biological characteristics of internal thoracic artery conduits are reviewed.

Off-Pump Coronary Revascularization for Left Main Coronary Artery Stenosis

Experience of on- and off-pump coronary artery bypass in 379 patients with significant left main coronary artery stenosis was retrospectively reviewed. Beating-heart operations were performed on 219 patients between January 2001 and October 2007. Their results were compared with 160 who underwent revascularization under cardiopulmonary bypass during the same period. All patients had multivessel grafting via a median sternotomy. Both groups were comparable demographically. Off-pump patients received significantly fewer grafts per patient (3.21 ± 0.86 vs 3.74 ± 0.82). The use of moderate or high doses of inotropics (> 5 μ g · kg−1 · min−1) was more frequent in the on-pump group (44% vs 26%). Postoperative blood transfusion requirement was lower in off-pump patients, and fewer of them experienced worsening of preexisting renal insufficiency. There were 2 operative deaths in the on-pump group and 1 in the off-pump group. The off-pump procedure is safe and effective in patients with left main coronary artery disease.

Impact of Preoperative Renal Dysfunction on Outcomes of Off-Pump Coronary Artery Bypass Grafting

BACKGROUND This study assessed whether preoperative renal insufficiency predisposes patients undergoing off-pump coronary artery revascularization to postoperative dialysis. METHODS From August 2004 through June 2009, 2,275 patients undergoing off-pump coronary artery bypass were categorized into five groups (stages) by glomerular filtration rate (GFR). Of these, 1,855 patients had renal insufficiency: stage 2: 1,406; stage 3: 428; stage 4: 21, and 414 had normal renal function, stage 1. Excluded were 6 patients with end-stage renal disease (stage 5). Preoperative variables and postoperative outcomes were compared among groups. RESULTS Preoperative patient characteristics were similar; however, patients with normal renal function were younger (p = 0.001). Serum creatinine rose significantly above baseline on the first postoperative day in the renal insufficiency groups (p = 0.001). The GFR groups had similar inotrope use, reexploration rate, duration of postoperative mechanical ventilation, postoperative stroke, wound infection, and mortality rate. Stage 4 patients had a higher incidence of postoperative myocardial infarction (p = 0.002). Stage 3 and 4 patients had an increased need for postoperative dialysis vs stage 1 patients (p = 0.002). CONCLUSIONS Nonparametric contingency analysis showed patients with low preoperative GFR (stage 3 and 4, p < 0.0001) and a history of smoking (p = 0.04) were at increased risk for postoperative dialysis. Patients who required postoperative inotropic support tended toward requiring postoperative dialysis (p = 0.06). Low preoperative ejection fraction (p = 0.83), class III or IV angina (p = 0.069), and postoperative blood transfusions were not associated with the need for postoperative dialysis in patients undergoing off-pump revascularization.

Does multi-vessel off-pump coronary artery bypass grafting reduce post operative morbidity compared to on-pump CABG?

BackgroundCardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried out to compare mortality and morbidity in the off-pump and on-pump CABG groups.MethodsWe prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL) pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared.ResultsOPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12% although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001).ConclusionThere was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and hospital stay in OPCAB group.

Correction of anomalous drainage of right superior vena cava to left atrium.

A 2-year-old boy with cyanosis was found to have normal situs and looping with anomalous drainage of a right-sided superior vena cava to the left atrium, and intact interatrial septum in association with anomalous drainage of the left pulmonary veins to the right superior vena cava. He underwent successful surgical repair of this rare congenital malformation.

Outcomes of Mitral Valve Repair for Chronic Ischemic Mitral Regurgitation

Mitral regurgitation is a frequent complication of ischemic heart disease. A retrospective study was performed on 127 patients with significant ischemic mitral regurgitation (regurgitant jet area ≥6.0 cm2 and/or vena contracta width ≥0.70 cm) who underwent elective mitral valve repair between January 2001 and October 2007. Concomitant myocardial revascularization was carried out in all except one patient, and left ventricular restoration in 8. All patients had ring annuloplasty, with release of posterior mitral leaflet tethering in 21, leaflet resection in 7, chordal transfer in 3, and chordal shortening in 2. There were 4 (3.1%) hospital deaths. Two patients underwent successful mitral valve replacement for repair failure in the immediate postoperative period, and one had an unsuccessful valve replacement at 3 months. During a mean follow-up of 19.65 ± 13.21 months in 121 patients, 111 had trivial or no residual regurgitation, and 10 had mild regurgitation. Mitral valve repair for chronic ischemic mitral regurgitation is a reproducible technique with satisfactory early and mid-term outcomes and freedom from valve-related complications.

Reduction of Sternal Infection in Off-pump CABG by Modified Pedicle Harvesting

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